以野生平榛(C.heterophylla Fisch.)雌花序为供试材料,研究榛子木质化花柱软化的方法.结果表明:(1)1.0 mol/L Na OH溶液浸泡并煮沸比相同处理下蒸馏水的软化效果好;(2)1.0 mol/L Na OH溶液浸泡材料并立即水煮软化20 min后的软化效果优...以野生平榛(C.heterophylla Fisch.)雌花序为供试材料,研究榛子木质化花柱软化的方法.结果表明:(1)1.0 mol/L Na OH溶液浸泡并煮沸比相同处理下蒸馏水的软化效果好;(2)1.0 mol/L Na OH溶液浸泡材料并立即水煮软化20 min后的软化效果优于其他处理时间;(3)苯胺蓝染色环境的缓冲液最佳p H范围为5.7至7.1.此改进方法可以在一天内即可完成榛子花粉管形态的观察,较传统软化方法简单、快捷.展开更多
Sexual reproduction in flowering plants requires that two sperm cells are delivered to the embryo sac where double fertilization of an egg cell and of a central cell results in the formation of a diploid embryo and of...Sexual reproduction in flowering plants requires that two sperm cells are delivered to the embryo sac where double fertilization of an egg cell and of a central cell results in the formation of a diploid embryo and of the triploid nutritional endosperm tissue. The immobile male gametes are delivered to the immobile female gametophyte by a single cell, the pollen tube. The pollen tube must be able to germinate on a genetically appropriate stigma and it must be directed through the transmitting tract of the style from where it must target an ovule. Moreover, the pollen tube must enter the ovule at a defined opening, the micropyle, grow toward one of the two synergids and release the two sperm cells upon contact. This complex process requires recognition events with chemically based or physically supported cell-cell communication as well as directional cues for the growing pollen tube. A number of molecules and mechanisms have been implicated in pollen tube guidance which are summarized in this review.展开更多
Summary Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the s...Summary Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a posi-tive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species (Orobancha- ceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin's functional hypothesis between pollen size and stigma depth.展开更多
文摘以野生平榛(C.heterophylla Fisch.)雌花序为供试材料,研究榛子木质化花柱软化的方法.结果表明:(1)1.0 mol/L Na OH溶液浸泡并煮沸比相同处理下蒸馏水的软化效果好;(2)1.0 mol/L Na OH溶液浸泡材料并立即水煮软化20 min后的软化效果优于其他处理时间;(3)苯胺蓝染色环境的缓冲液最佳p H范围为5.7至7.1.此改进方法可以在一天内即可完成榛子花粉管形态的观察,较传统软化方法简单、快捷.
文摘Sexual reproduction in flowering plants requires that two sperm cells are delivered to the embryo sac where double fertilization of an egg cell and of a central cell results in the formation of a diploid embryo and of the triploid nutritional endosperm tissue. The immobile male gametes are delivered to the immobile female gametophyte by a single cell, the pollen tube. The pollen tube must be able to germinate on a genetically appropriate stigma and it must be directed through the transmitting tract of the style from where it must target an ovule. Moreover, the pollen tube must enter the ovule at a defined opening, the micropyle, grow toward one of the two synergids and release the two sperm cells upon contact. This complex process requires recognition events with chemically based or physically supported cell-cell communication as well as directional cues for the growing pollen tube. A number of molecules and mechanisms have been implicated in pollen tube guidance which are summarized in this review.
基金supported by the National Science Foundation of China (Grants no.31270281, U1402267) to SQH
文摘Summary Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a posi-tive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species (Orobancha- ceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin's functional hypothesis between pollen size and stigma depth.