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排序方式: 共有262条查询结果,搜索用时 15 毫秒
61.
[目的]分析国内仅分布于新疆的野生蔬菜高葶韭的雌蕊形态变化特征与柱头可授性发生规律,为高葶韭的引种驯化及杂交育种提供理论依据.[方法]田间定株观察高葶韭雌蕊形态变化和开花动态,并分7个时期分别采用联苯胺-过氧化氢法及四甲基偶氮唑法检测柱头的可授性.[结果]高葶韭子房每心室具2枚胚珠,基部有3个具帘的蜜穴.在6枚花药散粉花丝萎蔫时花柱和柱头伸长,空间位置高于花药.单花花被片恰好完全闭合时柱头可授性最强.[结论]高葶韭为两性花、可育,单花花药散粉后柱头具有可授性直至花被片闭合、柱头萎蔫.联苯胺-过氧化氢法及四甲基偶氮唑法均可以在田间快速检测柱头育性.花器官存在空间位置的差异和开放的不同步性,雌蕊晚于雄蕊成熟,花柱在单花开放过程中有明显地伸长生长至外露,高葶韭具有为了保障异交成功的雌蕊特征. 相似文献
62.
Wu Xiaojin Yuan Longping Wang Weiping 《农业科学与技术》2005,6(2):2-6
In this study population improvement or random polycross plus mass selection was adopted with using N8S, Huaizao4, Xiang2B and Zaoyoul as parents. To help comprehensively improve the important characters such as combining ability, grain quality, resistance, stigma exsertion rate, etc. The stigma exsertion rate of ZhunS, an elite TGMS line, is 78.6%, 72.4% higher than that of V20A. Hybrids produced by crossing ZhunS with R402, Minhui77 and Minhui63 increased the yield by 3.8%-5.8% and decreased grain chalkiness by 82.1%-84.4% compared with those from crossing V20A with the corresponding R lines. 相似文献
63.
64.
为了提高海南砂的产量,研究了其小花数目、花粉活力、柱头可授性、落果率等生殖生物学特性以及海
南砂花粉在不同贮藏条件下的活力。结果表明,海南砂每个花序有7.28(依0.83)朵小花;小花的花期为1.5 d;离体萌
发法测定花粉活力在花朵刚刚开放时达83.6%,开花12 h后降为21.0%,24 h后降为11.4%;柱头和花粉在花朵开放
6 h 内都具极强可授性,寿命维持24 h,比花粉寿命长12 h以上;人工授粉率和自然授粉率分别为64.10(依29.80)%
和17.55(依15.49)%、落果率为20.65(依31.39)%和11.11(依32.34)%。高湿度条件下贮藏花粉12 h后活力降为0.6%,而
在低温高湿条件下贮藏花粉12 h的活力为23.4%,表明低温更有利于海南砂花粉贮藏。 相似文献
65.
通过田间调查、花粉离体萌发、石蜡切片和人工授粉等试验手段对锥栗的开花动态、花粉活力、柱头可授性、风媒传粉特性和授粉特性等进行研究。结果表明:锥栗雌花群体分化时间约40天,单花分化时间约22天,柱头可授性持续期为7天;雄花序4—5月开花,群体花期23~26天,群体盛花期13~15天,单花序花期10~12天,开花后6天内花粉保持较高活力。风媒传粉是锥栗传粉的主要途径,风速和风向是影响锥栗传粉的主要气象因素,顺风方向上花粉的传播距离及花粉通量显著高于其他3个方向。锥栗在去雄套袋且不进行人工授粉的处理下未坐果,表明锥栗不存在无融合生殖;异交授粉坐果率均显著高于自交,表明异交能显著提高锥栗坐果率,生产上需配置授粉树。 相似文献
66.
Wang Yanzhe Cui Yanhong Zhang Lihua Li Jincai Liu Jianfeng Wang Ronghuan 《Frontiers of Agriculture in China》2007,1(3):271-275
Kernel sets in corn were affected by silk receptivity, pollen grain vigor, and the synchronization of silking and pollen shedding.
Grain yield decrement was often caused by poor kernel set ability under field conditions. This study was conducted with two
corn hybrids—Yedan 12 and Yedan 19—in both field and laboratory to observe silk receptivity, pollen vigor, synchronization
of silking and pollen, and their effects on the kernel sets. The results showed that silk receptivity could be maintained
over a relatively longer period of time after silks emerged, but both kernel set percentage and kernel weight decreased as
silks aged when pollination occurred. Pollen grains that shed earlier had higher TTC-dehydrogenase activity, higher germination
percentage, more rapid pollen tube growth rate, and higher percentage of kernel sets and kernel weight than those that shed
later. The effect of delayed silking on kernel set ability was more significant compared with delayed pollen. Synchronization
of silking and pollen shedding showed different characters in different hybrids: “partial overlapped” for Yedan 12 and “overlapped”
for Yedan 19. 相似文献
67.
棉花柱头外露种质类型及其杂种一代的光温特性研究——Ⅱ.长日处理对棉花柱头外露光敏种质现蕾期和生育影响的研究 总被引:2,自引:3,他引:2
对棉花柱头外露4个光敏种质的不同叶龄期幼苗进行16h长日照处理,据观察结果表明:在南昌地区夏播条件下,凡通过1真叶期后的各叶龄期的自然光照(13.84h)处理,接着再给长日照,不能控制棉株现蕾的出现,只有在棉苗子叶期给予长日照,棉株才可能不现蕾,该类种质进行光照试验必须在1真叶平展以前进行处理才能得到正确的结论,棉花柱头外露光敏种质感光敏感期为子叶期至1真叶期。 相似文献
68.
阿蒂莫耶番荔枝人工授粉 总被引:5,自引:0,他引:5
阿蒂莫耶番荔枝(Axnona atemaya Hort)的花有雌蕊先熟现象。花药在傍晚6至8时裂开,人工授粉能提高座果率。其方法是用毛笔直接从花药自然裂开的花上取花粉并立即授在花药没裂开的花上,如果花药在授粉当日保持不裂开,3周后座果率为94.0%。如果花药在授粉后的短期内裂开,座果率为23.8%,与对照座果率(18.9%)没有差别,说明柱头容受性在花药裂开前的短期内完全消失。 相似文献
69.
A. K. Handique 《Euphytica》1986,35(2):631-632
Summary In nature, Solanum khasianum
Clarke (syn. S. varium
Dunal) is a self pollinated plant. However, artificial cross pollination is feasible when pollination is done around the time of anthesis, which is between 09.30 and 10.00. Due to prevalence of heterostyly bud selection has to be highly specific. 相似文献
70.
Summary Over a period of many years, data on dominance relationships of S-alleles in Brussels sprouts were collected at URL and IVT. The level of activity of S-alleles in heterozygotes was assessed on the basis of the number of pollen tubes that penetrated into the stigma. 209 out of 210 possible combinations between 21 S-alleles were used for this investigation. The S-alleles were grouped separately for activity in pollen and style on the basis of their sensitivity to lose activity in S-heterozygotes. Besides S-allele interaction per se, activity was found to be influenced by environment and genetic background.Results suggest that in stigma, co-dominance is the normal pattern and that deviations are caused by factors other than S-allele interaction as such.In pollen, only three truly recessive alleles were found. Besides several combinations with mutual weakening in pollen, examples of independent weakening were found. 相似文献