#oxalis hybrid

[crudlynaturephotos]

[lupinus-bicolor]

if ever i wanted to start a nonnative garden these shits would be the first things i'd plant

candy garden

[badolmen]

I want to someone rich to sponsor my mad botanist dreams. I would make so many unethical trees.

[botaniqueer]

The Oxalis gigantea is absolutely loaded with flowers! I’m wondering if these are everblooming and just keep flowering until they need to go dormant. (Which is unlikely in Seattle unless they’re on a strict yearly schedule like some of the other desert Oxalis.)

[plantcare]

What are the most suitable blooming house plants experts choose?

Top 10 indoor flower plants

African violet

African violets are among the easiest to grow flowering houseplants. They bloom year-round with little effort. Choose from hundreds of varieties and forms, some with variegated foliage or ruffled or white-edged blooms. African violet likes warm conditions and filtered sunlight. Avoid getting water on the fuzzy leaves; cold water causes unsightly brown spots. African violet is one of the most preferred plant by interior plant design experts.

Peace Lily

The peace lily is an easy-care plant that tolerates low light and low humidity. Flowers consist of a showy spoon-shaped white spathe and spike of creamy white flowers. Bloom is heaviest in summer, but many varieties bloom throughout the year. The glossy, lance-shaped leaves are attractive even when the plant has no blooms.

Hibiscus

Tropical hibiscus is the ultimate plant for creating a touch of the tropics. It forms huge blooms, up to 8 inches in diameter, on a shrubby upright plant that you can train to grow as a tree. Individual blossoms last only a day or two, but plants bloom freely from late spring through fall and occasionally through winter. Keep the soil uniformly moist and give the plant as much indoor light as possible to keep it blooming.

Oxalis

Oxalis bears triangular, clover-like purple leaves and an almost constant show of pink or white blooms. Look for varieties that have plain green foliage with or without silvery accents. Oxalis grows from small bulbils in the soil; you can divide these any time the plant becomes crowded in its pot.

Anthurium

Anthuriums bloom in festive shades of pink, red, lavender, or white, and last for two months or more. They also make a long-lasting cut flower if you can bear to cut them. Anthurium needs a medium to bright light to bloom well but can be grown as a foliage plant with less light.

Jasmine

There are many types of jasmine. Many-flowered jasmine, polyanthus, and Arabian jasmine are two of the easiest to grow; just give them plenty of light and moisture. They'll all bear fragrant pink to white blooms on vining plants.

Flowering Maple

Crepe-paper-like blooms in shades of red, pink, orange, or yellow dangle among leaves like festive lanterns. Many varieties have splotched or variegated foliage for extra interest. Grow the plant upright as a tree, prune it back to keep it shrubby, or even grow it in a hanging basket. Its common name comes from the leaves, which resemble those of a maple tree.

Kaffir Lily

Kaffir lily is also commonly called clivia. As a houseplant, it usually blooms in winter with clusters of up to 20 reddish-orange or yellow tubular flowers. Clivia blooms only when it has been exposed to cool, dry conditions, so give it lower temperatures in winter and keep it on the dry side. With its deep green strap-like leaves aligned in a single plane, the plant is attractive even when not in bloom.

Streptocarpus

Also called Cape primrose, Streptocarpus blooms almost continuously if given the right conditions. Most of the hundreds of hybrid varieties available bear trusses of pink, white, purple, or red flowers, often with contrasting white or yellow throats. Except for providing cooler winter temperatures, treat it as you would its cousin, African violet.

Calamondin Orange

This hybrid between a mandarin orange and kumquat bears fragrant white blossoms in late winter or spring. The wonderfully fragrant flowers develop into showy 1-inch-diameter orange fruits on a shrubby plant with glossy green foliage. Fruits can remain on the plant for many weeks.

  Whether it is an office or a home Interior plants and flowers always bring extreme joy and a soothing atmosphere for you. Plant Care Specialists, Fort Lauderdale has 20 years of experience in this field assuring the greatest results of interior plant maintenance service, Fort Lauderdale. We provide the best interior plant maintenance in Hollywood, FL, to make your plants truly flourish and thrive. We expertise in floral designs and blooming and are providing the most reasonable charge and bring quick results. If you wish to add your home and office a new look with nature’s greatest gifts, then contact our team of experts and consume the best interior plant care service Fort Lauderdale.

Contact Details :

Plantcare Specialist

 Contact Number: 954-371-2042 

Email ID: plantcarespecialist@gmail.com

 Address: 2801 NW 6th Avenue Wilton Manors, FL 33311

[supremeuppityone]

Written for Klaroline Valentine's Day Bingo 2020 @kcvalentinesbingo

Prompt: “His name is NOT ‘Cupid McDimples’!”

Author’s note: This is the much-requested sequel to Chapter 67: The Best Safety Plan, found in my Klaroline series, A Beautiful Symmetry.

Please review here.

           It started with a dozen candy cane sorrels delivered in an exquisite crystal vase.

           “Oxalis versicolors?! Those have to be shipped in from South Africa!”

           Caroline rolled her eyes at Bonnie, doing her best to fight back a silly grin as she read the note from Klaus: Thinking of you. She still wasn’t sure what to think of their encounter with the hot weirdo in the woods who thinks he’s an immortal Viking hybrid something with fangs who buried Damon’s body for them in exchange for a date with her. And he’s probably a psycho killer. And a week ago she was worried her life had become dull.

           And then he sent a platinum and diamond encrusted charm bracelet. From the exclusive Arcadius flame logo, she probably could’ve funded her and Bonnie’s practice for the next year if she pawned it. It was beautifully designed and somehow perfectly tailored to her background and tastes — from the miniature eye chart and glasses charms to the scrolled letter ‘C’, her sapphire birthstone, and, surprisingly, a raven. How the hell did he know “The Raven” was her favorite poem?

           “Cupid McDimples is stepping up his game,” Bonnie teased as she eyed the shiny bracelet. “Can’t wait to see what he has planned for your date. Well, our date since I’m going with you in case he actually is a crazy murderer and we need to get all shovel-happy again.”

           “His name is NOT Cupid McDimples! He’s a random lunatic we ran into and it’s entirely possible he wants to wear our skin. And damn right you’re going with me since you’re the one who suggested I go on the date in the first place AFTER he admitted to being in the woods for a body dump. Come to think of it, shovels might be a good idea.” Letting out along-suffering sigh, she added, “Of course someone that attractive would have some glaring defects.”

           “Not to throw stones, but you two lovelies were traipsing about the woods for the same reason,” Klaus’ amused voice suddenly interrupted, startling them both. With a dimpled smirk, he held out two shovels, cheekily topped by frilly pink bows. “In case you decide to end our date by getting ‘shovel-happy’.”

           Seriously? There was no reason for her heart to be fluttering like this over a pair of shovels. And yet it was. She couldn’t remember the last time she’d been so charmed. “Are you always so considerate with your dates?”

           “Honestly, I can’t recall the last date I went on,” he remarked, his accented voice warm and inviting. “Does sharing a glass of champagne with one of the chambermaids at Tuileries count as a date? We were having a rather lovely time before the Parisian mob invaded and the royals marked it as a prudent time to flee.”  

           “You’re seriously talking about the French Revolution. Like you were there,” Caroline replied flatly, throwing an exasperated glance at Bonnie.

           Swinging her shovel up until the handle rested on a shoulder, Bonnie muttered, “Why the hell not? Caroline’s last date was convinced a powerful secret society is running the Starbucks franchise, which is why they’re on every corner.”

           Favoring him with a wink, Caroline kept a grip on her shovel while linking her other arm with his. “I do enjoy a good nervous breakdown.”

                                      ______________________

           There was a delicious-looking meal set out in the auditorium. She’d been surprised when Klaus drove them to a community theater, and immediately squealed when she saw they were performing a series of Poe’s works. “Poe is my favorite author! I had no idea this was going on.”

           She could’ve sworn the tips of his ears turned red and his voice was a bit tight as he said, “Yes, well, what a coincidence.” As a handsome man with a blinding white smile stepped out of the shadows, he nodded his head at Bonnie and said, “I brought along Marcel to keep you company. Marcel is a...friend.”

           Bonnie studied the stranger skeptically, but Caroline also noticed a flicker of interest in her friend’s gaze. So, clearly she wasn’t the only one who had terrible taste in men. “And I suppose Marcel’s a werewolf-vampire Viking too?”

           “Actually, I was a plantation slave in Louisiana. Just a little over 200 now,” Marcel replied silkily, with enough of a flirty undertone that Bonnie’s eye twitched.

           Caroline snorted, telling her friend, “See? I told you all the hot ones were crazy.”

           Marcel threw back his head, laughing. “I’ve been perfectly sane for years now. The Quarter Coven isn’t nearly as powerful as they think.”

           As Klaus held out a chair for Caroline, he wryly answered, “Now, let’s not be too hasty — you weren’t under a spell when you summoned my father to try to kill me after you returned from World War I.”

           Seriously?! French Revolution. Werewolf-vampire Viking. Plantation slave. Witch coven. World War I. Caroline exchanged a look with Bonnie, in which they wordlessly weighed the hot-to-crazy ratio of their dates and decided to just roll with it. Besides, the dating pool was far too shallow in their little town to be overly picky. What’s a bit of crazy between friends?

           The antique sconces along the walls began to flash, signaling the performance would begin soon despite the empty theater. Confused, Caroline leaned over to whisper in Klaus’ ear, “Are we early? Where’s the rest of the audience?”

           Marcel gleefully explained, “Klaus bought out the whole place. In fact, he actually hired them to—”

           “Try the saffron crab cakes, Marcel. It seems your mouth needs to be occupied,” Klaus interrupted, cheeks slightly pink as he couldn’t quite meet Caroline’s inquisitive gaze.

           Was Marcel going to reveal that Klaus paid an acting troupe to perform Poe’s works because he was her favorite author? Seriously?! The last date she went on wanted her to reimburse him for the drinks because she ended the date early after he told her that he and his twin sister just loved blondes and ‘shared everything’. “You’re really setting the bar high for our second date,” she told Klaus, enjoying the hopeful gleam in his gray eyes.

           “Second date? That’s quite forward of you, sweetheart,” he teased. “I’ll need a bit more wooing before I agree to a second date.”

           She couldn’t help but return his impish grin. “Then I probably need to figure out your favorite author.”

           “I’m quite fond of Chaucer. Now, he’s heralded as one of the greatest English poets of the Middle Ages, but in his time, kept getting into quarrels with those who believed legitimate literature should be written only in French or Latin. I might’ve had a compelling argument in ensuring his proper burial at Westminster Abbey.”

           Caroline rolled her eyes as she replied, “And after that, you gave Columbus directions and helped Henry VIII hire a divorce lawyer.”

           He chuckled, caressing her hand with his thumb. His voice low and seductive as he murmured, “You are a delight.”

           Nearly identical snorts came from Bonnie and Marcel’s table, but Caroline couldn’t be bothered as her heart did that fluttery thing again while Klaus looked at her. Onstage, the red velvet curtains rose to reveal a cozy fireplace and an actor in a wingback chair. From the ominous bird perched on the bookcase overhead, it looked like she’d be treated to her favorite poem first.

           Since it was Poe, the shrill screams backstage seemed to blend perfectly with the foreboding atmosphere, and it wasn’t until the sounds of furniture breaking and muted thuds against walls reached her ears that Caroline realized something was wrong. The lone actor who’d been sitting in the chair seemed paralyzed with fear as a pale young man strutted onto the stage, a single trail of blood at the corner of his mouth.

           If it wasn’t for the blood, Caroline would’ve dismissed him as another pretty boy who’d never love anyone as much as he loved himself. The supercilious curl of his smile gave her chills — not to mention the black veins that crawled underneath his eyes. Plus, there were fangs. Actual fangs.

           “Klaus, I’ve come for your kingdom — and your head,” he proclaimed with a snarling hiss.

           Wow. Apparently monsters are a thing. Caroline couldn’t help her knee-jerk reaction as she blurted out, “So, werewolf-vampire Viking or plantation slave?”

           Although clearly in shock, Bonnie managed to reply, “Probably not plantation slave.”

           Klaus snickered, seemingly pleased by the women’s ability to keep a sense of humor during this bizarre situation. “Actually, Lucien’s just an upstart stable boy.”

           As Klaus and Marcel both bared their fangs, leaping onto the stage to face off with Lucien in a whoosh of air that was impossible to comprehend, Caroline started thinking that maybe those shovels would come in handy after all.

[niche-plants]

. 意図しない場所から❁⃘*.ﾟ まぶしい✨✨から 目立って撮ってくれ📷って 言ってるみたい 遊んで帰ってきたら ハウスは３５℃🥵 やばいやばいと見に行ったら 🍃彡OUT換気扇が不具合で停止 すぐ直して水遣り🚿 昼寝予定返上でε-(´∀｀; )ﾌｩ これからは高音にも注意の季節ですね🙃 . #Oxalis ' #momonokagayaki ' #オキザリス #桃の輝き #桃の輝き_niche #bulb #球根 #hybrid #多肉植物 #多肉 #succulents #succulent #taniku #flower #nonfilter #Oxalis_niche — view on Instagram https://ift.tt/35e4SwR

[wallpapernifty]

Reasons Why Red Perennial Flowers Is Getting More Popular In The Past Decade | Red Perennial Flowers

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from Wallpaper Nifty https://www.flowernifty.com/reasons-why-red-perennial-flowers-is-getting-more-popular-in-the-past-decade-red-perennial-flowers/

[megansplants]

Plant death count since I left for Peru in July:

Golden Pothos (Epipremnum aureum)

Rattlesnake Plant (Calathea lancifolia) -- on the way out 

Prayer Plant (Maranta leuconeura) -- this was my fault, I was hoping to propagate more vines and I trimmed when I shouldn’t have....

Polka Dot Plant (Hypoestes phyllostachya)

African Mask, Elephant Ear, Alocasia Plant (Amazonica, Alocasia ?) ‘Polly’

Spiderwort, Wandering Jew (Tradescantia pallida) (x2 -- pink and purple)

Peacock Fern, Rainbow Moss (Selaginella uncinata)

False Purple Shamrock (Oxalis triangularis)

Paddle Plant (Kalanchoe luciae)

Campfire Plant (Crassula capitella thyrsiflora)

x Sedeveria (Sedum / Echeveria hybrid)

Cliff Maids (Lewisia cotyledon) -- arguably one of my saddest deaths

There are a variety of reasons why they all died, some things that happened while I was gone, and some now that I’ve come back.

Some were overwatered while I was gone, some got too little or too much sunshine. Unfortunately, some of this damage is going to be permanent, and even though I switched back to their original care once I made it back to the states, they died anyways. 

Since coming back and moving into my new house, the light, humidity, and temperature have been so different that some of my plants just couldn’t adjust.

Some plants have really begun to thrive in the new conditions, but I lost maybe 1/3 of all my plants in the three-month transition. 

[margdarsanme]

NCERT Class 12 Biology Chapter 2 Sexual Reproduction in Flowering Plants

NCERT Class 12 Solutions for Biology Chapter 2 Sexual Reproduction in Flowering Plants

QUESTIONS FROM TEXTBOOK SOLVED

1. Name the parts of anangiosperm flower in which development of male and female gametophytes take place.Ans. Development of male gametophyte (micro- gametogenesis) occurs in pollen sac of anther up to 2 – celled stage. The female gametophyte develops (megagametogenesis) in the nucellus of ovule.

2. Differentiate between microsporogenesis and megasporogenesis. Which type of cell division occurs during these events? Name the structures formed at the end of these two events?Ans.Differences between microsporogenesis and megasporogenesis are as follows –

Each microspore mother cell and megaspore mother cell contain two sets of chromosomes and are therefore diploid. The diploid megaspore mother cell and microspore mother cell enlarges and undergo meiosis to produce, four haploid cells called megaspores and microspores respectively.The chromosome number is reduced by half and therefore megaspores and microspores are haploid.Microsporogenesis and megasporogenesis give rise to pollen grains and embryo sac respectively. Pollen grain is the male gametophyte and embryo sac represents the female gametophyte.

3. Arrange the following terms in- the correct developmental sequence : Pollen grain, sporogenous tissue, microspore tetrad, pollen mother cell, male gametes.Ans. Sporogenous tissue – pollen mother cell – microspore tetrad – pollen grains – male gametes.

4. With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.Ans.A typical angiospermic ovule is a small structure which is formed in the ovary. Ovule first develops as a projection on the placenta and composed of multilayered cellular tissue called the nucellus. The hypodermal cell of die nucellus enlarges and transformed into megaspore mother cell. This cell undergoes meiosis to produce four haploid cells only one of which develops & forms embryo sac (female gametophyte). An ovule may be surrounded by one or two protective layers called integuments, leaving a small opening at one end termed as micropyle which acts as passage for the entry of the pollen tube into the ovule. Thus, a typical ovule consists of a fully developed embryo sac with the nucellus and integuments.

5. What is meant by monosporic development of female gametophyte?Ans. In many flowering plants, only one out of the four megaspores enlarges and develops into female gametophyte or embryo sac. The other three megaspores degenerate. This type of embryo sac formation is called as monosporic type of development.

6. With a neat diagram explain the 7-celled, 8- nucleate nature of the female gametophyte.Ans.Embryo sac (or female gametophyte) is formed by three successive mitotic divisions that take place in the nucleus of megaspore.The nucleus of the functional megaspore divides meiotically to form two nuclei which move to the opposite poles, forming the 2-nucleate embryo sac. Two more sequential mitotic nuclear divisions result in the formation of the 4-nucleate and later the 8-nucleate stages of the embryo sac. After the 8-nucleate stage, cell walls are laid down leading to the organisation of the typical female gametophyte or embryo sac. Six of the eight nuclei are grouped together at micropylar and chalazal end and form the egg apparatus and antipodals respectively. The large central cell left over with two polar nuclei. Thus, a typical female gametophyte consists of 7 cells with 8 nucleus.

7. What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.Ans. Chasmogamous flowers or open flowers in which anther and stigma are exposed for pollination. Cross-pollination cannot occur in cleistogamous flowers. These flowers remain closed thus causing only self-pollination. In cleistogamous flowers, anthers dehisce inside the closed flowers. So the pollen grains come in contact with stigma. Thus there is no chance of cross¬pollination, e.g., Oxalis, Viola.

8. Mention two strategies evolved to prevent self-pollination in flowers.Ans. Continued self-pollination decreases the vigour and vitality of a particular race. Thus, flowering plants have developed many devices to discourage self-pollination and to encourage cross-pollination.Dichogamy and self-sterility are.two most common devices that ensure cross-pollination. Dichogamy – Maturation of anther and stigma at different times in a bisexual flower prevent self-pollination.Self-sterility (or self-incompatibility) – Due to the presence of self-sterile gene in some flowers, pollen grains do not germinate on the stigma of that flowers. e.g.,- tobacco, potato.

9. What is self-incompatibility? Why does self-pollination not lead to seed formation in self-incompatible species?Ans. When the pollen grains of an anther do not germinate on the stigma of the same flower, then such a flower is called self-sterile or incompatible and such condition is known as self¬incompatibility or self-sterility.The transference of pollen grains shed from the anther to the stigma of the pistil is called pollination. This transference initiate the process of seed formation. Self-pollination is the transfer of pollen grain shed from the anther to stigma of pistil in the same flower. But in some flower self¬pollination does not lead to the formation of seed formation because of the presence of same sterile gene on pistil and pollen grain.

10. What is bagging technique? How is it useful in a plant breeding programme?Ans. It is the covering of emasculated flowers (removal of anthers in bud condition from a bisexual flower by a bag of butter paper or polythene in their bud condition i.e., before anthesis) to prevent contamination of its stigmas with unwanted pollens. When the stigmas of emasculated flowers mature the bags are removed, stigmas are dusted with pollen grains of desired male . plants by means of a presterilized brush and flowers are rebagged till fruit develop. This technique is mainly used in artificial hybridization. Plant breeders often use this technique to prevent the contamination of stigma of the flowers from unwanted pollen grains.

11. What b triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion.Ans. Fusion of second male gamete with die two polar nuclei located in the central cell to form the triploid primary endosperm nucleus (PEN) is called triple fusion or vegetative fertilization. This process takes place in the embryo sac. After reaching the ovary, pollen tube enters into the embryo sac from the micropylar end. After penetration, the tip of the pollen tube ruptures releasing the two male gametes. The one male gamete fuses with the egg to form the diploid zygote. This process is called syngamy and the other male gamete fuses with the two polar nuclei to form the triploid primary endosperm & this process is known as triple fusion. These two events of fertilization constitute the process of double fertilization.

12. Why do you think the zygote is dormant for sometime in a fertiUsed ovule?Ans. The zygote after a period of rest develops into embryo. Most zygotes remain dormant till certain amount of endosperm forms. They do so, to provide assured nutrition to the developing embryo.

13. Differentiate between:(a)hy pocotyl and epicotyl;(b)coleoptile and coleorrhiza;(c)integument and testa;(d)perisperm and pericarp.Ans:

14. Why is apple called a false fruit? Which Part(s) of the flower forms the fruit?Ans. Botanically ripened ovary is called a true fruit. The fruits in which thalamus and other floral parts develop along with the ovary are called false fruits. For example – apple, strawberry, cashew etc. In apple the main edible portion of the fruit is the fleshy thalamus. Ovary forms the fruit after fertilization or without fertilization in parthenocarpic fruits.

15. What is meant by emasculation? When and why does a plant breeder employ this technique?Ans. Emasculation is the removal of stamens mainly the anthers from the flower buds before their dehiscence. This is mainly done to avoid self-pollination. Emasculation is one of the measures in the artificial hybridization. Plant breeders employed this technique to prevent the pollination within same flower or to pollinate stigmas with pollens of desired variety.

16. If one can induce parthenocarpy through the application of growth substances, which fruits would you select to induce parthenocarpy and why?Ans. Parthenocarpic fruits are seedless. They develop from ovary without fertilization. Banana, grapes, oranges, Pineapple, Guava, Watermelon, lemon are selected because these seedless of units are of high economic importance. The fruits in which seeds or seed part form edible portion (e.g.,Pomegranate) are not selected to induce parthenocarpy.

17. Explain the role of tapetum in the formation of pollen-grain wall.Ans. Tapetum is the innermost layer of the microsporangium. The tapetal cells are multinucleated and polyploid. They nourish the developing pollen grains. These cells contain ubisch bodies that help in the ornamentation of the microspores or pollen grains walls. The outer layer of the pollen grain is called exine and is made up of the sporopollenin secreted by the ubisch bodies of the tapetal cells. This compound provides spiny appearance to the exine of the pollen grains.

18. What is apomixis and what is its importance?Ans. Apomixis is a mode of asexual reproduction that produces seeds without fertilization, e.g.- some species of Asteraceae and Grasses. This method is important in hybrid seed industry. Hybrids are extensively cultivated for increasing productivity. But the main drawback is that the hybrid seeds are to be produce every year because the seeds of the hybrid plants da not maintain hybrid characters for longer period due to segregation of characters. This can be avoided if apomixis can be introduced in hybrid seeds. For this reason scientists are trying hard to identify genes for apomixis.

from Blogger http://www.margdarsan.com/2020/09/ncert-solutions-for-class-12-biology_17.html

[bethestaryouareradio]

Awaken Spring

“The ghostly winter silences have given way to the great spring murmur of awakening life.” Jack London

It all began when I witnessed the new growth unfurling on one of my loquat trees. The leaves were a mesmerizing bright green, like the color of lime with a hint of sunshine. Ah, sunshine, I thought! How I longed for warm, sun-drenched days. The darkness, cold, and wet of winter had begun to unravel my soul.

The rains throughout the winter, although welcome and necessary, have been torrential. The creeks are full and raging. If only we could save this H2O to quench summer thirsty landscapes. Our hillsides are carpets of emerald grasses. The only hint that salvation was near was the happy stalks of the ubiquitous daffodils singing to the sky an end to the melancholia.

I wanted to bottle a bit of this luminosity from those loquat leaves so I did the next best thing…I painted my fingernails the exact color! An odd choice, I’ve been told, but I was hell-bent on awakening spring.

The next day, the weather reports suggested that we would bask in sunlight for at least a week. My earthy polish must have summoned the gods of rebirth.

As if on cue, terra firma has erupted in a procession of power plants. Besides the narcissi and bergenia that have been blooming successively since January, we now witness muscari, tulip, hyacinth, ranunculus, anemone, oxalis, calla lily, azalea, freesia, Chinese fringe, blue star grass, and one of my favorite over-looked specimen, hellebore joining the parade.

Hellebores are a deer resistant, low maintenance perennial that stirs with blooms (actually sepals protecting the flower) before other plants. Known as the Lenten rose, they prefer partial shade, are evergreen and boast flowers January through May. If you plant them on a slope, you’ll be able to see the flowers more easily as their stems face downwards. Hybrids include shades of ivory, jade, maroon, pink, yellow, speckled, and fringed combinations.

As the soil warms and the daylight hours grow longer, it is time to prepare your garden for seeding by weeding, hoeing, and adding rich soil. This year I have chosen packets from Renee’s Garden (https://sh2543.ositracker.com/121062/9151) and have already jotted down when the seeds will be planted. At the end of March or beginning of April, I will be planting beets, leeks, and clarkia. In April I will add cleome, columbine, and dwarf dahlias. Brussels sprouts will wait for a summer sowing. Pumpkin seeds that I’ve saved will be planted in late May in anticipation of Halloween and Thanksgiving. If you want to carve them, choose a fun variety such as Warty Goblin or Super Moon. For that delicious holiday pie, the go-to favorite is Pik-a-Pie. Pumpkins need a large area to grow making it essential to plan now to give your Curcubita pepo the room to thrive. Small pumpkins need a 12-foot area, medium pumpkins require 24 feet, and giants want a 36-48 feet space per plant.

Are you thinking of including perennials that will attract butterflies, bees, bats, and birds? The National Pollinator Garden Network has announced it has surpassed its goal of registering one million pollinator gardens. In just three years, 1,040,000 gardens were registered with the Million Pollinator Garden Challenge. From tiny yards to public gardens, the million-plus gardens add up to a network of approximately five million acres of enhanced or new pollinator habitat. Offer a buffet with a diverse array of flowers, herbs, colors, fragrances, sizes, and shapes that will encourage these garden guards to visit and stay.

The elegant tulip soulangeana magnolia adds beauty and structure to any landscape and now is the time to choose a specimen in full bloom at your local nursery. Blooming time varies with varieties and micro-climates. Santa Rosa plum and peach trees are radiantly blossoming and will soon form fruit. Crab apple will follow shortly. Hopefully, the rains won’t knock off too many buds.

The frogs are chirping, birds are tweeting, and cows are mooing. The orchestra of nature waking up from its winter slumber is music to my ears. It’s time to polish our dancing shoes (and maybe your nails) as the vernal equinox has arrived with an equal balance of light and dark. The season of spring has sprung.

Cynthia Brian’s Mid Month Reminders

CREATE a cutting garden for summer by planting delphiniums, snapdragons, and sunflowers. VISIT http://www.RecycleSmart.org for dates of the 5th Annual Compost Giveaway. Register to collect up to three yards of free compost or “black gold” which has been recycled from the green organic bins. FERTILIZE lawns. Spring is also the second-best time after fall to install a new lawn or refresh an old one. If you are seeding, March and April are excellent times to scatter seed, especially before a rain. My preference is http://www.PearlsPremium.com for an almost weed-free, lush green ground cover. ADD to your planting list aeoniums and other succulents as they require minimal maintenance and water, even in the hot months. CONTINUE to pick up the fallen branches of camellias. I know I’m sounding like a broken record but camellias have a long blooming season and the ones that drop will cause a rot for next year’s bloom. Don’t stop picking them up and don’t add them to your compost or recycle bins. BUY seeds for spring sowing from Renee’s Garden (https://sh2543.ositracker.com/121062/9151) Through March 24 you can get FREE Shipping on orders over $20.00. STOP mowing your lawns when the grass is wet or it is raining. Hearing the growl of lawnmowers when it is pouring outside boils the soul of my inner gardener. Cutting the grass when it is raining damages the grass blades and causes ruts and compaction. Inform your “mow, blow, and go” service providers to perform other tasks in inclement weather. A healthy green lawn will thank you for your restraint.

Happy Gardening. Happy Growing. Hello Spring!

Read more at https://www.lamorindaweekly.com/archive/issue1302/Digging-Deep-with-Cynthia-Brian-Awaken-spring.html

  Cynthia Brian, The Goddess Gardener, raised in the vineyards of Napa County, is a New York Times best-selling author, actor, radio personality, speaker, media and writing coach as well as the Founder and Executive Director of Be the Star You Are1® 501 c3. Tune into Cynthia’s Radio show and order her books at www.StarStyleRadio.com. Buy a copy of her new books, Growing with the Goddess Gardener and Be the Star You Are! Millennials to Boomers at www.cynthiabrian.com/online-store. Hire Cynthia for projects, consults, and lectures. Cynthia@GoddessGardener.com

www.GoddessGardener.com

Donate to Fire Disaster Relief via Be the Star You Are!® 501 c3 at www.BethestarYouAre.org

[goddessgardener]

Awaken Spring

“The ghostly winter silences have given way to the great spring murmur of awakening life.” Jack London

It all began when I witnessed the new growth unfurling on one of my loquat trees. The leaves were a mesmerizing bright green, like the color of lime with a hint of sunshine. Ah, sunshine, I thought! How I longed for warm, sun-drenched days. The darkness, cold, and wet of winter had begun to unravel my soul.

The rains throughout the winter, although welcome and necessary, have been torrential. The creeks are full and raging. If only we could save this H2O to quench summer thirsty landscapes. Our hillsides are carpets of emerald grasses. The only hint that salvation was near was the happy stalks of the ubiquitous daffodils singing to the sky an end to the melancholia.

I wanted to bottle a bit of this luminosity from those loquat leaves so I did the next best thing…I painted my fingernails the exact color! An odd choice, I’ve been told, but I was hell-bent on awakening spring.

The next day, the weather reports suggested that we would bask in sunlight for at least a week. My earthy polish must have summoned the gods of rebirth.

As if on cue, terra firma has erupted in a procession of power plants. Besides the narcissi and bergenia that have been blooming successively since January, we now witness muscari, tulip, hyacinth, ranunculus, anemone, oxalis, calla lily, azalea, freesia, Chinese fringe, blue star grass, and one of my favorite over-looked specimen, hellebore joining the parade.

Hellebores are a deer resistant, low maintenance perennial that stirs with blooms (actually sepals protecting the flower) before other plants. Known as the Lenten rose, they prefer partial shade, are evergreen and boast flowers January through May. If you plant them on a slope, you’ll be able to see the flowers more easily as their stems face downwards. Hybrids include shades of ivory, jade, maroon, pink, yellow, speckled, and fringed combinations.

As the soil warms and the daylight hours grow longer, it is time to prepare your garden for seeding by weeding, hoeing, and adding rich soil. This year I have chosen packets from Renee’s Garden (https://sh2543.ositracker.com/121062/9151) and have already jotted down when the seeds will be planted. At the end of March or beginning of April, I will be planting beets, leeks, and clarkia. In April I will add cleome, columbine, and dwarf dahlias. Brussels sprouts will wait for a summer sowing. Pumpkin seeds that I’ve saved will be planted in late May in anticipation of Halloween and Thanksgiving. If you want to carve them, choose a fun variety such as Warty Goblin or Super Moon. For that delicious holiday pie, the go-to favorite is Pik-a-Pie. Pumpkins need a large area to grow making it essential to plan now to give your Curcubita pepo the room to thrive. Small pumpkins need a 12-foot area, medium pumpkins require 24 feet, and giants want a 36-48 feet space per plant.

Are you thinking of including perennials that will attract butterflies, bees, bats, and birds? The National Pollinator Garden Network has announced it has surpassed its goal of registering one million pollinator gardens. In just three years, 1,040,000 gardens were registered with the Million Pollinator Garden Challenge. From tiny yards to public gardens, the million-plus gardens add up to a network of approximately five million acres of enhanced or new pollinator habitat. Offer a buffet with a diverse array of flowers, herbs, colors, fragrances, sizes, and shapes that will encourage these garden guards to visit and stay.

The elegant tulip soulangeana magnolia adds beauty and structure to any landscape and now is the time to choose a specimen in full bloom at your local nursery. Blooming time varies with varieties and micro-climates. Santa Rosa plum and peach trees are radiantly blossoming and will soon form fruit. Crab apple will follow shortly. Hopefully, the rains won’t knock off too many buds.

The frogs are chirping, birds are tweeting, and cows are mooing. The orchestra of nature waking up from its winter slumber is music to my ears. It’s time to polish our dancing shoes (and maybe your nails) as the vernal equinox has arrived with an equal balance of light and dark. The season of spring has sprung.

Cynthia Brian’s Mid Month Reminders

CREATE a cutting garden for summer by planting delphiniums, snapdragons, and sunflowers. VISIT http://www.RecycleSmart.org for dates of the 5th Annual Compost Giveaway. Register to collect up to three yards of free compost or “black gold” which has been recycled from the green organic bins. FERTILIZE lawns. Spring is also the second-best time after fall to install a new lawn or refresh an old one. If you are seeding, March and April are excellent times to scatter seed, especially before a rain. My preference is http://www.PearlsPremium.com for an almost weed-free, lush green ground cover. ADD to your planting list aeoniums and other succulents as they require minimal maintenance and water, even in the hot months. CONTINUE to pick up the fallen branches of camellias. I know I’m sounding like a broken record but camellias have a long blooming season and the ones that drop will cause a rot for next year’s bloom. Don’t stop picking them up and don’t add them to your compost or recycle bins. BUY seeds for spring sowing from Renee’s Garden (https://sh2543.ositracker.com/121062/9151) Through March 24 you can get FREE Shipping on orders over $20.00. STOP mowing your lawns when the grass is wet or it is raining. Hearing the growl of lawnmowers when it is pouring outside boils the soul of my inner gardener. Cutting the grass when it is raining damages the grass blades and causes ruts and compaction. Inform your “mow, blow, and go” service providers to perform other tasks in inclement weather. A healthy green lawn will thank you for your restraint.

Happy Gardening. Happy Growing. Hello Spring!

Read more at https://www.lamorindaweekly.com/archive/issue1302/Digging-Deep-with-Cynthia-Brian-Awaken-spring.html

  Cynthia Brian, The Goddess Gardener, raised in the vineyards of Napa County, is a New York Times best-selling author, actor, radio personality, speaker, media and writing coach as well as the Founder and Executive Director of Be the Star You Are1® 501 c3. Tune into Cynthia’s Radio show and order her books at www.StarStyleRadio.com. Buy a copy of her new books, Growing with the Goddess Gardener and Be the Star You Are! Millennials to Boomers at www.cynthiabrian.com/online-store. Hire Cynthia for projects, consults, and lectures. Cynthia@GoddessGardener.com

www.GoddessGardener.com

Donate to Fire Disaster Relief via Be the Star You Are!® 501 c3 at www.BethestarYouAre.org

[botaniqueer]

My Oxalis triangularis plants (the purple ones) and O. gigantea (The tree-like Oxalis) are both in bloom!

Time to see if they can hybridize! I’m hoping for something arboraceous like O. gigantea but with purple leaves.

(Assuming the color is Mendelian and purple is dominant. Idk how stem type genetics would work though. Esp since this is tubers vs. arboraceous stems.)

[botaniqueer]

regnum-plantae replied to your photo “My Oxalis triangularis plants (the purple ones) and O. gigantea (The...”

I hate to be the bearer of bad news, but I've tried my hand with hybridising a few species of Oxalis with O. Triangularis with no success, all before researching the topic and realising O. Triangularis doesn't naturally set seeds and Oxalis species don't readily hybridise due to they're wild variations in ploidy, even within the same species :s

Dang :/ I suspected this may be the case with how little searches about Oxalis hybridization yielded online despite how common they are as houseplants.

[margdarsanme]

NCERT Class 12 Biology Chapter 2 Sexual Reproduction in Flowering Plants

NCERT Class 12 Solutions for Biology Chapter 2 Sexual Reproduction in Flowering Plants

QUESTIONS FROM TEXTBOOK SOLVED

1. Name the parts of anangiosperm flower in which development of male and female gametophytes take place.Ans. Development of male gametophyte (micro- gametogenesis) occurs in pollen sac of anther up to 2 – celled stage. The female gametophyte develops (megagametogenesis) in the nucellus of ovule.

2. Differentiate between microsporogenesis and megasporogenesis. Which type of cell division occurs during these events? Name the structures formed at the end of these two events?Ans.Differences between microsporogenesis and megasporogenesis are as follows –

Each microspore mother cell and megaspore mother cell contain two sets of chromosomes and are therefore diploid. The diploid megaspore mother cell and microspore mother cell enlarges and undergo meiosis to produce, four haploid cells called megaspores and microspores respectively.The chromosome number is reduced by half and therefore megaspores and microspores are haploid.Microsporogenesis and megasporogenesis give rise to pollen grains and embryo sac respectively. Pollen grain is the male gametophyte and embryo sac represents the female gametophyte.

3. Arrange the following terms in- the correct developmental sequence : Pollen grain, sporogenous tissue, microspore tetrad, pollen mother cell, male gametes.Ans. Sporogenous tissue – pollen mother cell – microspore tetrad – pollen grains – male gametes.

4. With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.Ans.A typical angiospermic ovule is a small structure which is formed in the ovary. Ovule first develops as a projection on the placenta and composed of multilayered cellular tissue called the nucellus. The hypodermal cell of die nucellus enlarges and transformed into megaspore mother cell. This cell undergoes meiosis to produce four haploid cells only one of which develops & forms embryo sac (female gametophyte). An ovule may be surrounded by one or two protective layers called integuments, leaving a small opening at one end termed as micropyle which acts as passage for the entry of the pollen tube into the ovule. Thus, a typical ovule consists of a fully developed embryo sac with the nucellus and integuments.

5. What is meant by monosporic development of female gametophyte?Ans. In many flowering plants, only one out of the four megaspores enlarges and develops into female gametophyte or embryo sac. The other three megaspores degenerate. This type of embryo sac formation is called as monosporic type of development.

6. With a neat diagram explain the 7-celled, 8- nucleate nature of the female gametophyte.Ans.Embryo sac (or female gametophyte) is formed by three successive mitotic divisions that take place in the nucleus of megaspore.The nucleus of the functional megaspore divides meiotically to form two nuclei which move to the opposite poles, forming the 2-nucleate embryo sac. Two more sequential mitotic nuclear divisions result in the formation of the 4-nucleate and later the 8-nucleate stages of the embryo sac. After the 8-nucleate stage, cell walls are laid down leading to the organisation of the typical female gametophyte or embryo sac. Six of the eight nuclei are grouped together at micropylar and chalazal end and form the egg apparatus and antipodals respectively. The large central cell left over with two polar nuclei. Thus, a typical female gametophyte consists of 7 cells with 8 nucleus.

7. What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.Ans. Chasmogamous flowers or open flowers in which anther and stigma are exposed for pollination. Cross-pollination cannot occur in cleistogamous flowers. These flowers remain closed thus causing only self-pollination. In cleistogamous flowers, anthers dehisce inside the closed flowers. So the pollen grains come in contact with stigma. Thus there is no chance of cross¬pollination, e.g., Oxalis, Viola.

8. Mention two strategies evolved to prevent self-pollination in flowers.Ans. Continued self-pollination decreases the vigour and vitality of a particular race. Thus, flowering plants have developed many devices to discourage self-pollination and to encourage cross-pollination.Dichogamy and self-sterility are.two most common devices that ensure cross-pollination. Dichogamy – Maturation of anther and stigma at different times in a bisexual flower prevent self-pollination.Self-sterility (or self-incompatibility) – Due to the presence of self-sterile gene in some flowers, pollen grains do not germinate on the stigma of that flowers. e.g.,- tobacco, potato.

9. What is self-incompatibility? Why does self-pollination not lead to seed formation in self-incompatible species?Ans. When the pollen grains of an anther do not germinate on the stigma of the same flower, then such a flower is called self-sterile or incompatible and such condition is known as self¬incompatibility or self-sterility.The transference of pollen grains shed from the anther to the stigma of the pistil is called pollination. This transference initiate the process of seed formation. Self-pollination is the transfer of pollen grain shed from the anther to stigma of pistil in the same flower. But in some flower self¬pollination does not lead to the formation of seed formation because of the presence of same sterile gene on pistil and pollen grain.

10. What is bagging technique? How is it useful in a plant breeding programme?Ans. It is the covering of emasculated flowers (removal of anthers in bud condition from a bisexual flower by a bag of butter paper or polythene in their bud condition i.e., before anthesis) to prevent contamination of its stigmas with unwanted pollens. When the stigmas of emasculated flowers mature the bags are removed, stigmas are dusted with pollen grains of desired male . plants by means of a presterilized brush and flowers are rebagged till fruit develop. This technique is mainly used in artificial hybridization. Plant breeders often use this technique to prevent the contamination of stigma of the flowers from unwanted pollen grains.

11. What b triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion.Ans. Fusion of second male gamete with die two polar nuclei located in the central cell to form the triploid primary endosperm nucleus (PEN) is called triple fusion or vegetative fertilization. This process takes place in the embryo sac. After reaching the ovary, pollen tube enters into the embryo sac from the micropylar end. After penetration, the tip of the pollen tube ruptures releasing the two male gametes. The one male gamete fuses with the egg to form the diploid zygote. This process is called syngamy and the other male gamete fuses with the two polar nuclei to form the triploid primary endosperm & this process is known as triple fusion. These two events of fertilization constitute the process of double fertilization.

12. Why do you think the zygote is dormant for sometime in a fertiUsed ovule?Ans. The zygote after a period of rest develops into embryo. Most zygotes remain dormant till certain amount of endosperm forms. They do so, to provide assured nutrition to the developing embryo.

13. Differentiate between:(a)hy pocotyl and epicotyl;(b)coleoptile and coleorrhiza;(c)integument and testa;(d)perisperm and pericarp.Ans:

14. Why is apple called a false fruit? Which Part(s) of the flower forms the fruit?Ans. Botanically ripened ovary is called a true fruit. The fruits in which thalamus and other floral parts develop along with the ovary are called false fruits. For example – apple, strawberry, cashew etc. In apple the main edible portion of the fruit is the fleshy thalamus. Ovary forms the fruit after fertilization or without fertilization in parthenocarpic fruits.

15. What is meant by emasculation? When and why does a plant breeder employ this technique?Ans. Emasculation is the removal of stamens mainly the anthers from the flower buds before their dehiscence. This is mainly done to avoid self-pollination. Emasculation is one of the measures in the artificial hybridization. Plant breeders employed this technique to prevent the pollination within same flower or to pollinate stigmas with pollens of desired variety.

16. If one can induce parthenocarpy through the application of growth substances, which fruits would you select to induce parthenocarpy and why?Ans. Parthenocarpic fruits are seedless. They develop from ovary without fertilization. Banana, grapes, oranges, Pineapple, Guava, Watermelon, lemon are selected because these seedless of units are of high economic importance. The fruits in which seeds or seed part form edible portion (e.g.,Pomegranate) are not selected to induce parthenocarpy.

17. Explain the role of tapetum in the formation of pollen-grain wall.Ans. Tapetum is the innermost layer of the microsporangium. The tapetal cells are multinucleated and polyploid. They nourish the developing pollen grains. These cells contain ubisch bodies that help in the ornamentation of the microspores or pollen grains walls. The outer layer of the pollen grain is called exine and is made up of the sporopollenin secreted by the ubisch bodies of the tapetal cells. This compound provides spiny appearance to the exine of the pollen grains.

18. What is apomixis and what is its importance?Ans. Apomixis is a mode of asexual reproduction that produces seeds without fertilization, e.g.- some species of Asteraceae and Grasses. This method is important in hybrid seed industry. Hybrids are extensively cultivated for increasing productivity. But the main drawback is that the hybrid seeds are to be produce every year because the seeds of the hybrid plants da not maintain hybrid characters for longer period due to segregation of characters. This can be avoided if apomixis can be introduced in hybrid seeds. For this reason scientists are trying hard to identify genes for apomixis.

via Blogger https://ift.tt/2RD1h12

[margdarsanme]

NCERT Class 12 Biology Chapter 2 Sexual Reproduction in Flowering Plants

NCERT Class 12 Solutions for Biology Chapter 2 Sexual Reproduction in Flowering Plants

QUESTIONS FROM TEXTBOOK SOLVED

1. Name the parts of anangiosperm flower in which development of male and female gametophytes take place.Ans. Development of male gametophyte (micro- gametogenesis) occurs in pollen sac of anther up to 2 – celled stage. The female gametophyte develops (megagametogenesis) in the nucellus of ovule.

2. Differentiate between microsporogenesis and megasporogenesis. Which type of cell division occurs during these events? Name the structures formed at the end of these two events?Ans.Differences between microsporogenesis and megasporogenesis are as follows –

Each microspore mother cell and megaspore mother cell contain two sets of chromosomes and are therefore diploid. The diploid megaspore mother cell and microspore mother cell enlarges and undergo meiosis to produce, four haploid cells called megaspores and microspores respectively.The chromosome number is reduced by half and therefore megaspores and microspores are haploid.Microsporogenesis and megasporogenesis give rise to pollen grains and embryo sac respectively. Pollen grain is the male gametophyte and embryo sac represents the female gametophyte.

3. Arrange the following terms in- the correct developmental sequence : Pollen grain, sporogenous tissue, microspore tetrad, pollen mother cell, male gametes.Ans. Sporogenous tissue – pollen mother cell – microspore tetrad – pollen grains – male gametes.

4. With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.Ans.A typical angiospermic ovule is a small structure which is formed in the ovary. Ovule first develops as a projection on the placenta and composed of multilayered cellular tissue called the nucellus. The hypodermal cell of die nucellus enlarges and transformed into megaspore mother cell. This cell undergoes meiosis to produce four haploid cells only one of which develops & forms embryo sac (female gametophyte). An ovule may be surrounded by one or two protective layers called integuments, leaving a small opening at one end termed as micropyle which acts as passage for the entry of the pollen tube into the ovule. Thus, a typical ovule consists of a fully developed embryo sac with the nucellus and integuments.

5. What is meant by monosporic development of female gametophyte?Ans. In many flowering plants, only one out of the four megaspores enlarges and develops into female gametophyte or embryo sac. The other three megaspores degenerate. This type of embryo sac formation is called as monosporic type of development.

6. With a neat diagram explain the 7-celled, 8- nucleate nature of the female gametophyte.Ans.Embryo sac (or female gametophyte) is formed by three successive mitotic divisions that take place in the nucleus of megaspore.The nucleus of the functional megaspore divides meiotically to form two nuclei which move to the opposite poles, forming the 2-nucleate embryo sac. Two more sequential mitotic nuclear divisions result in the formation of the 4-nucleate and later the 8-nucleate stages of the embryo sac. After the 8-nucleate stage, cell walls are laid down leading to the organisation of the typical female gametophyte or embryo sac. Six of the eight nuclei are grouped together at micropylar and chalazal end and form the egg apparatus and antipodals respectively. The large central cell left over with two polar nuclei. Thus, a typical female gametophyte consists of 7 cells with 8 nucleus.

7. What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.Ans. Chasmogamous flowers or open flowers in which anther and stigma are exposed for pollination. Cross-pollination cannot occur in cleistogamous flowers. These flowers remain closed thus causing only self-pollination. In cleistogamous flowers, anthers dehisce inside the closed flowers. So the pollen grains come in contact with stigma. Thus there is no chance of cross¬pollination, e.g., Oxalis, Viola.

8. Mention two strategies evolved to prevent self-pollination in flowers.Ans. Continued self-pollination decreases the vigour and vitality of a particular race. Thus, flowering plants have developed many devices to discourage self-pollination and to encourage cross-pollination.Dichogamy and self-sterility are.two most common devices that ensure cross-pollination. Dichogamy – Maturation of anther and stigma at different times in a bisexual flower prevent self-pollination.Self-sterility (or self-incompatibility) – Due to the presence of self-sterile gene in some flowers, pollen grains do not germinate on the stigma of that flowers. e.g.,- tobacco, potato.

9. What is self-incompatibility? Why does self-pollination not lead to seed formation in self-incompatible species?Ans. When the pollen grains of an anther do not germinate on the stigma of the same flower, then such a flower is called self-sterile or incompatible and such condition is known as self¬incompatibility or self-sterility.The transference of pollen grains shed from the anther to the stigma of the pistil is called pollination. This transference initiate the process of seed formation. Self-pollination is the transfer of pollen grain shed from the anther to stigma of pistil in the same flower. But in some flower self¬pollination does not lead to the formation of seed formation because of the presence of same sterile gene on pistil and pollen grain.

10. What is bagging technique? How is it useful in a plant breeding programme?Ans. It is the covering of emasculated flowers (removal of anthers in bud condition from a bisexual flower by a bag of butter paper or polythene in their bud condition i.e., before anthesis) to prevent contamination of its stigmas with unwanted pollens. When the stigmas of emasculated flowers mature the bags are removed, stigmas are dusted with pollen grains of desired male . plants by means of a presterilized brush and flowers are rebagged till fruit develop. This technique is mainly used in artificial hybridization. Plant breeders often use this technique to prevent the contamination of stigma of the flowers from unwanted pollen grains.

11. What b triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion.Ans. Fusion of second male gamete with die two polar nuclei located in the central cell to form the triploid primary endosperm nucleus (PEN) is called triple fusion or vegetative fertilization. This process takes place in the embryo sac. After reaching the ovary, pollen tube enters into the embryo sac from the micropylar end. After penetration, the tip of the pollen tube ruptures releasing the two male gametes. The one male gamete fuses with the egg to form the diploid zygote. This process is called syngamy and the other male gamete fuses with the two polar nuclei to form the triploid primary endosperm & this process is known as triple fusion. These two events of fertilization constitute the process of double fertilization.

12. Why do you think the zygote is dormant for sometime in a fertiUsed ovule?Ans. The zygote after a period of rest develops into embryo. Most zygotes remain dormant till certain amount of endosperm forms. They do so, to provide assured nutrition to the developing embryo.

13. Differentiate between:(a)hy pocotyl and epicotyl;(b)coleoptile and coleorrhiza;(c)integument and testa;(d)perisperm and pericarp.Ans:

14. Why is apple called a false fruit? Which Part(s) of the flower forms the fruit?Ans. Botanically ripened ovary is called a true fruit. The fruits in which thalamus and other floral parts develop along with the ovary are called false fruits. For example – apple, strawberry, cashew etc. In apple the main edible portion of the fruit is the fleshy thalamus. Ovary forms the fruit after fertilization or without fertilization in parthenocarpic fruits.

15. What is meant by emasculation? When and why does a plant breeder employ this technique?Ans. Emasculation is the removal of stamens mainly the anthers from the flower buds before their dehiscence. This is mainly done to avoid self-pollination. Emasculation is one of the measures in the artificial hybridization. Plant breeders employed this technique to prevent the pollination within same flower or to pollinate stigmas with pollens of desired variety.

16. If one can induce parthenocarpy through the application of growth substances, which fruits would you select to induce parthenocarpy and why?Ans. Parthenocarpic fruits are seedless. They develop from ovary without fertilization. Banana, grapes, oranges, Pineapple, Guava, Watermelon, lemon are selected because these seedless of units are of high economic importance. The fruits in which seeds or seed part form edible portion (e.g.,Pomegranate) are not selected to induce parthenocarpy.

17. Explain the role of tapetum in the formation of pollen-grain wall.Ans. Tapetum is the innermost layer of the microsporangium. The tapetal cells are multinucleated and polyploid. They nourish the developing pollen grains. These cells contain ubisch bodies that help in the ornamentation of the microspores or pollen grains walls. The outer layer of the pollen grain is called exine and is made up of the sporopollenin secreted by the ubisch bodies of the tapetal cells. This compound provides spiny appearance to the exine of the pollen grains.

18. What is apomixis and what is its importance?Ans. Apomixis is a mode of asexual reproduction that produces seeds without fertilization, e.g.- some species of Asteraceae and Grasses. This method is important in hybrid seed industry. Hybrids are extensively cultivated for increasing productivity. But the main drawback is that the hybrid seeds are to be produce every year because the seeds of the hybrid plants da not maintain hybrid characters for longer period due to segregation of characters. This can be avoided if apomixis can be introduced in hybrid seeds. For this reason scientists are trying hard to identify genes for apomixis.

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