These events included the migration of microspores and vegetative nucleus and a polar pollen engorgement process.

在小孢子液泡化后期黄色网站久久久久，小孢子核和細(xì)胞質(zhì)遠(yuǎn)離小孢子萌發(fā)孔和絨氈層呈極性分布国产人妖。

Megaspore mother cell just enters leptotene as The meiosis of microspore mother cell develop into tetrads . The meiosis of megaspore mother cell develop into pachytene while that of microspores develop into a single nuclear adjacent to cell wall.

當(dāng)白楊小孢子母細(xì)胞減數(shù)分裂至四分體時毛片视频免费观看高清在线，大孢子母細(xì)胞開始進(jìn)入減數(shù)分裂細(xì)線期欧美色日；而當(dāng)小孢子發(fā)育至單核靠邊期上時91在线视频免费观看，大孢子母細(xì)胞減數(shù)分裂達(dá)到粗線期无码专区三级片免费用在线观看。

In seed plants also produce spores, and spores are profiled in the ovule Pearl hearts a megaspore mother cell produces large spores by meiosis in the anthers of the microspore mother cells produced by meiosis of microspore.

在種子植物中也產(chǎn)生孢子，且均為孢子異型在线亚洲国产一区日本，在胚珠的珠心中的1個大孢子母細(xì)胞經(jīng)減數(shù)分裂產(chǎn)生大孢子国产精品有限公司，在花藥中的小孢子母細(xì)胞經(jīng)減數(shù)分裂產(chǎn)生小孢子。

Microspore Ye as the feather, small sporophyll sac formed by the polymerization, each polymer capsules formed by four small sporangia, small spores with dual airbags, and airbag Pinaceae pollen is similar to large sporophyll from the central axis and arranged in Brachypodium feather composition, Each Yibing has a shell bucket, each bucket containing shell upright ovules 10-12 months.

小孢子葉枝為羽狀欧美高清中文字幕国产精选，小孢子葉由聚合囊組成91久久久无码国产，每個聚合囊由4個小孢子囊組成，小孢子具雙氣囊最新系列亚洲国产专区，與松科植物花粉的氣囊相似亚洲黄色网站干干干，大孢子葉由中軸及羽狀排列的短柄組成，每一柄上有一個殼斗大型日韩精品网站视频在线观看免费，每個殼斗內(nèi)有10—12個直立的胚珠男女性爱过程视频。

The observation showed that sterile plants and fertile plants in the pollen mother cell stage is not very different, when microspore mother cells of male sterile plants enter meiosis period, it could form normal tetrad cell , tetrad cell is normal in early development stage, In the uninucleate microspore stage , tapetal cells were vacuolization, the microspores were extruded to the middle by tapetal cells.

本研究利用石蠟切片法，結(jié)合光學(xué)顯微鏡技術(shù)對櫻桃蘿卜核質(zhì)互作雄性不育系的不育株和對應(yīng)保持系可育株的花藥發(fā)育過程進(jìn)行細(xì)胞形態(tài)學(xué)觀察国产粗口粗暴国产一级视频，觀察結(jié)果表明：不育株與可育株在花粉母細(xì)胞時期差別不大免费久久性爱视频，不育株的花藥小孢子母細(xì)胞進(jìn)入減數(shù)分裂期后日韩操逼片，可以正常的形成四分體，四分體前期發(fā)育正常国产专区91在线，而在單核小孢子期絨氈層細(xì)胞出現(xiàn)液泡化欧美激情大色堂丁香五月，絨氈層細(xì)胞向中間擠壓小孢子。

The results show that the normal process begins with archesporial cell and undergoes stages of primary and secondary sporogenous cell,microspore mother cell,dyad,tetrad,central nucleus microspore,vacuolated microspore,mature microspore,twocell pollen and threecell mature pollen.

對平流層輻射處理SP3谷子和對照CK3谷子雄性細(xì)胞發(fā)育的研究表明毛片一级毛片一级毛片一级，雄性細(xì)胞正常發(fā)育過程從孢原細(xì)胞開始无码区无码区视频网网址，經(jīng)初生造孢細(xì)胞、次生造孢細(xì)胞激情黄片免费观看、小孢子母細(xì)胞羞羞的漫画在线看、二分體、四分體和單核小孢子中央期日本色视、單核小孢子液泡期久在线免费观看视频、單核小孢子成熟期直到二細(xì)胞花粉、三細(xì)胞成熟花粉結(jié)束久久亚洲私人国产精品。

The reproductive development process of birch was described as follows: Male inflorescences extended from apical bud in early June. In later June, stamen primodium was differentiated in the bract of male inflorescence and the differentiation of bract was generated in female inflorescence. During July, anther layers and archesporial cell were differentiated in anther, then archesporial cell developed into mother microspore cell. Pistil primodium came into being at the same time. In early part of August the meiosis of mother microspore cell started. In later August, mono-nucleus microspore was formed. After September, both male inflorescence and female inflorescence were dormant.

白樺的生殖生長發(fā)育過程如下：6月初永久免费A片在线看视频一，雄花序從頂芽中生長出來。6月中下旬久久成爱，雄花序苞片上分化出雄蕊原基www.精品视频，雌花序分化出苞片。7月91精品国产精品，雄花花藥分化出花藥壁和孢原細(xì)胞免费A片中文字幕网址，孢原細(xì)胞演化為小孢子母細(xì)胞，雌花序苞腋處分化出雌蕊原基色呦哟网站；8月中上旬美女爆操视频，小孢子母細(xì)胞減數(shù)分裂，8月下旬形成單核小孢子www.在线看黄；9月后雄花序以單核小孢子狀念越冬欧美人人妻人人操，雌花序以雌蕊原基狀念越冬。

The results showed that the sex ratio of trees was 1 m 2 f, and the natural T. cuspidata tree was able to sexually reproduce for many years. Male trees had fecundity when the diameter at breast height ranged from 1.5 cm to 92 cm, while female trees had fecundity when the DBH from 9.5 cm to 68.1 cm. Male trees typically flowered at the age about 20 years earlier than female trees. The numbers of microstrobili were 3 times more than that of megastrobili, and only 1/10 megastrobili developed into seed. The numbers of strobili and seed were correlated with DBH, crown diameter and height of trees; however, no significant correlations were observed with other site factors. Numbers of strobili decreased from the upper to lower canopy layers, while the quantity of seed decreased from the middle, upper to lower canopy layers. Seed-setting rate increased from the upper to lower canopy layers. Numbers of strobili and seeds in different directions of the canopy were not uniform, but the differences weren't significant.

結(jié)果表明：現(xiàn)實東北紅豆杉天然種群中95视，♀♂性比為1：2欧美性交黄片A片；天然東北紅豆杉有性生殖持續(xù)時間長日韩一区二区三区免费拍拍，雄株胸徑在1.5~92cm99性爱精品视频网，雌株胸徑在9.5~68.1cm保持生殖狀態(tài)，雄株較雌株早約20年進(jìn)入花期日韩欧美图片；天然東北紅豆杉小孢子葉球數(shù)量平均為大孢子葉球數(shù)量的3倍7色在色在线视频，大孢子葉球轉(zhuǎn)化為果實的數(shù)量不足1/10，孢子葉球數(shù)量日本高清一道本一区二区、結(jié)實數(shù)量與樣株的胸徑欧洲美女A视频一级毛片、冠幅黄色网站污污污亚洲免费、樹高顯著相關(guān)，與其他立地因子相關(guān)不顯著98精品自拍视频在线观看；孢子葉球數(shù)量在冠層間的分布呈現(xiàn)由上至下的遞減規(guī)律一级特黄特色黄色网站，而結(jié)實數(shù)量在冠層間沿中、上日韩二区免费黄色网站、下遞減干干视频，結(jié)實率沿冠層自上而下遞增；孢子葉球與結(jié)實數(shù)量在樹冠不同朝向上也呈現(xiàn)出一定的特點一级精品毛片在线观看网站，但總體上差異不顯著找黄色性网。

Paraffin slides observation found that the microspore of the RNMS line failed to vacuolate after its morphogenesis, disassembled and disappeared at last. After microspore morphogenesis, the breaking down of tapetum cells was delayed until microspore breading down.

石蠟切片細(xì)胞學(xué)觀察，發(fā)現(xiàn)該隱性核不育能形成正常的四分體孢子A片网站资源，四分體釋放出小孢子后日韩系列在线精品视频观看网站免费，在單核花粉進(jìn)入液泡化時小孢子的發(fā)育異常，不進(jìn)行正常的液泡化国产精品99久久99，逐漸開始解體和消失97久久超碰；相應(yīng)的絨氈層在小孢子形成后的降解延遲，絨氈層細(xì)胞的體積略有增大人妻A∨无码中出综合网，在小孢子降解快結(jié)束時也很快解體18分钟处雏之好疼高清视频。

The situation of abnormal development of male cells is as follows:microspore mother cell can't enter into meiosis because of intense vacuolation,shrink and disintegration of its cytoplasm;although vacuolated microspore mother cell can enter into meiosis,it can't form normal dyad and degenerate in the middle process;dyad and tetrad become vacuolated and can't develop normally;cytoplasm of microspore shrinks around the nucleus at the stage of central nucleus microspore,the shape of microspore is twisted into crescent or irregular shape,at last its cytoplasm and nucleus are disintegrated and crescent vacant microspore presents;nutritive substances can't be accumulated at the stage of vacuolated microspore,cytoplasm is disintegrated,and microspore turns into a big vacant pollen.

雄性細(xì)胞異常發(fā)育有幾種情況：小孢子母細(xì)胞強烈液泡化，細(xì)胞質(zhì)收縮解體A级毛片大全免费，不能進(jìn)入減數(shù)分裂av黄色在线免费观看；小孢子母細(xì)胞液泡化，雖能進(jìn)入減數(shù)分裂九九视频在线观看A片，但不能形成正常二分體而中途退化亚洲日韩一线在线观看网站；二分體、四分體細(xì)胞液泡化九色视频jiuse在线，不能進(jìn)行正常發(fā)育a片视频在线看；單核小孢子中央期，細(xì)胞質(zhì)收縮包圍核在线A级毛片无码免费真人版，小孢子形狀扭曲呈月牙形或不規(guī)則形艹你综合，最終細(xì)胞質(zhì)和核解體而呈月牙形的空殼小孢子；單核液泡期的小孢子不能積聚營養(yǎng)物質(zhì)国产黄页在线观看黄A∨，細(xì)胞質(zhì)解體而成為大的空殼花粉粒黄色网站一级A片按摩。