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991.
植物花粉管中类整联蛋白的免疫荧光定位研究 总被引:1,自引:0,他引:1
利用免疫荧光技术,分别用整联蛋白β_3、α_y亚基胞质域抗血清及整联蛋白VnR(Vitronectin的受体)的抗血清在百合花粉管中检测出荧光标记,且在花粉管尖端逐渐增强,而用FnR(纤粘连蛋白的受体)、LnR(层粘连蛋白的受体)的抗血清及非免疫血清对照实验在百合花粉管中则没有或仅有很弱的荧光。在萌发的碧桃花粉管中,用β_1、β_3亚基胞质域抗血清也能检测出荧光标记,初步结果显示花粉管在生长过程中,质膜上有可能存在类整联蛋白,并且在百合花粉管中这种类整联蛋白可能是由α_v和β_3两种亚基组成的Vn样蛋白的受体。 相似文献
992.
Summary To determine whether phenylalanine ammonia-lyase (EC 4.3.1.5) is involved in the maturation of microspores to fertile pollen, anthers of a fertile strain of broccoli (Brassica oleracea L.) were studied in a comparison with anthers of a cytoplasmic male sterile strain. In the normal fertile strain, immature anthers of about 2 mm in length exhibited higher phenylalanine ammonia-lyase activity than mature anthers or those shorter than 2 mm. The 2-mm-long anthers corresponded to the mononucleate stage, just after release of the microspores during pollen development. Immunohistochemical localization of phenylalanine ammonia-lyase in the anthers indicated that the protein was present predominantly in the tapetal cells. The immature anthers of cytoplasmic male sterile broccoli had a lower phenylalanine ammonia-lyase activity than those of the normal fertile strain. The level of phenylalanine ammonia-lyase activity in the immature anthers was positively correlated with the number of fertile pollen grains at the flowering stage in both strains. It seems possible, therefore, that phenylpropanoid metabolism, which involves phenylalanine ammonia-lyase, may play an important role in the maturation of microspores in flowering plants.Abbreviations CHS
chalcone synthase
- CMS
cytoplasmic male sterility
- DAPI
4, 6-diamidmo-2-phenylindole dihydrochloride
- PAL
L-phenylalanine ammonia-lyase 相似文献
993.
Biao?Liu ChongRen?XuEmail author Fengming?Yan Ruizhong?Gong 《Biodiversity and Conservation》2005,14(14):3487-3496
Transgenic cotton containing a synthetic version of the insecticidal toxin gene from Bacillus thuringiensis subsp. kurstaki has been planted in China in a large scale and may have adverse impacts on honeybees. The pollens of the transgenic cotton
and the non-transgenic parental cotton were collected and their impacts on worker bees were tested. Experimental results showed
that the transgenic cotton pollen had no oral acute toxic effects on worker bees. No significant difference was observed in
the superoxide dismutases activity and the longevity of worker bees fed with diets containing the transgenic cotton pollen
or non-transgenic parental cotton pollen. The results of our experiment indicate that the transgenic cotton has no direct
adverse impacts on honeybees. Further work needs to be carried out to evaluate the long-term and indirect impacts of the transgenic
cotton on honeybees. 相似文献
994.
Wide hybridization in okra 总被引:5,自引:0,他引:5
C. A. Fatokun 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,74(4):483-486
Summary Crosses were made between members of the two West African okra types Soudanien and Guineen. All crosses succeeded in both directions and the F1 plants which showed hybrid vigour for plant stature were partially sterile. Cytological observations of the F1 plants revealed abnormal meiosis which resulted in the production of microspores of variable sizes. The frequency of viable pollen (as indicated by acetocarmine staining) was low in the hybrids: 35.80% (U.I.92× U.I.313) and 39.41% (1bk-1×U.I.215). The number of seeds produced per fruit was low in the hybrids and only a few of these seeds are viable. The possibility of gene transfer between the two okra types was discussed. 相似文献
995.
996.
997.
陕西中部黄土高原地区空气花粉组成及其与气候因子的关系——以洛川县下黑木沟村为例 总被引:1,自引:0,他引:1
空气花粉研究是现代孢粉学、植被变迁与预测的重要内容之一.陕西省黄土高原地区洛川县2007-2009连续2a的空气花粉分析表明:空气花粉组成与区域植被分布特征和植物花期一致.与2007—2008年相比,2008-2009年的花粉总通量及蒿属花粉通量明显增加,但木本植物花粉通量降低,这主要与2008-2009年降水明显偏少密切相关.2007-2008年降雨量高于500 mm,花粉组合中乔木花粉百分比高于30%,表现出森林植被特点;2008-2009年降雨量少于450 mm,花粉组合中草本花粉高于80%,乔木花粉低于10%,更多表现出草原植被特点.但从植被观测来看并没有明显的变化,表明花粉组合较植被对气候变化更为敏感.主要花粉类型与气候因子的相关分析表明:气候因子影响空气花粉的组成及数量.栎属、松属、蔷薇科花粉数量主要受春季温度影响,温度越高花粉数量越多;其他季节花粉数量主要受相对湿度影响,湿度越低,花粉数量越大.榆属花粉数量主要与冬季温度有关,温度越高,花粉数量越高.杨属只受春季温度影响,春季温度越低,花粉数量越多.胡颓子科花粉含量主要受春季相对湿度、风速影响,相对湿度越低,风速越大,花粉数量越多.绝大多数草本花粉数量均主要受春、冬季相对湿度及风速影响,相对湿度越低,风速越大,花粉数量越高;此外,禾本科花粉数量还受春季温度影响,温度越高,花粉数量越多;菊科花粉数量在夏秋季节还受温度、湿度和风速的共同影响,温度越低,湿度越低,风速越大,花粉数量越多.这些结果表明,黄土高原中部地区的空气花粉特征能反映区域植被组成,且对气候变化非常敏感,对认识和预测当地气候变化与植被动态等具有重要意义. 相似文献
998.
应用花粉匀浆物质诱导花生遗传性状变异的初步研究 总被引:2,自引:0,他引:2
本研究以开封白皮花生品种为受体。用具有选择标记性状的1218品种花粉匀浆为供体,处理发育成熟的该受体植株柱头,再用受体正常花粉授粉,获得了具有目标牲状变异的后代。其中,荚果的大小、结果数和种皮颜色等性状的转化更为明显。以上结果在不同试验、不同组合中,均得到重复。试验表明,此方法在花生育种上具有较大的实际应用价值。但具体技术和选育程序,根据花生的生物学特点还有待进一步研究。 相似文献
999.
1000.
A mixed‐species bird flock is a social assemblage where two or more bird species are moving together while foraging and might benefit from increased foraging efficiency and antipredator vigilance. A “mega‐flock,” which includes flocking species from different vegetation strata, often exhibits high species diversity. Mechanisms for the formation of mega‐flocks have not yet been explored. In this study, we evaluated the influence of vegetation structure and bird species diversity in driving the occurrence of mega‐flocks. We investigated the composition of mixed‐species flocks, local bird communities, and vegetation structure in five vegetation types of two high‐elevation sites in central Taiwan. Mega‐flocks occurred more frequently in pine woodland than later successional stages of coniferous forests. However, species richness/diversity of local bird communities increased along successional stages. Therefore, vegetation variables exhibit more influence on the occurrence of mega‐flocks than local bird communities. Besides foliage height diversity, understory coverage also showed positive effects on flock size of mixed‐species flocks. Our results indicated that pine woodlands with more evenly distributed vegetation layers could facilitate the interactions of canopy and understory flocks and increase the formation of mega‐flocks and thus the complexity of mixed‐species flocks. 相似文献