Leaves are of fundamental importance to plants, representing their facility to generate power and are the sensing units of plants towards the environment. An attempt was made to characterize and compare the variations...Leaves are of fundamental importance to plants, representing their facility to generate power and are the sensing units of plants towards the environment. An attempt was made to characterize and compare the variations of leaf morphology of various Populus deltoides Bartr. clones by studying the winter buds and other leaf parameters of fully developed leaves. To achieve these objectives, forty-three exotic and indigenous clones ofP. deltoides Bartr. were evaluated for different parameters. On the basis of various morphological characteristics the results reveal that each clone has a distinct color pattern of leaves. Different colors observed in these clones varied from light green through green to dark green. Two distinct lengths of the leaf apex were found, i.e., short and long; as well both acuminate and acute apex types were found. Erratic distribution of serration of leaves was also found. In this study, the morphological traits of leaves provided discriminatory grounds for separating various populations of P. deltoides Bartr. clones. Winter bud studies indicate that different clones vary considerably with regard to shape, color, shape of leaf scars and exudation.展开更多
Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red so...Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red soil is the most widely covered soil type in the world,and it is also the most suitable soil type for crape myrtle planting.The flower buds of crape myrtle(Lagerstroemia indica)planted in red soil were employed as experimental materials in this study,and the distinct periods of differentiation were identified using stereomicroscopy and paraffin sectioning.We optimized the steps of dehydration,transparency,embedding,sectioning and staining when employing paraffin sections.When seen under a microscope,this optimization can make the cell structure of paraffin sections obvious,the tissue structure complete,and the staining clear and natural.The flower bud differentiation process is divided into 7 periods based on anatomical observations of the external morphology and internal structure during flower bud differentiation:undifferentiated period,start of differentiation period,inflorescence differentiation period,calyx differentiation period,petal differentiation period,stamen differentiation period,and pistil differentiation period.The differentiation time is concentrated from the end of May to mid-June.Crape myrtle flower bud differentiation is a complicated process,and the specific regulatory mechanism and affecting elements need to be investigated further.展开更多
As a woody grass,bamboo has special reproductive habits with an extremely long vegetative phase.Pleioblastus pygmaeus is a kind of ornamental dwarf bamboo species with high ecological and economic value in China.There...As a woody grass,bamboo has special reproductive habits with an extremely long vegetative phase.Pleioblastus pygmaeus is a kind of ornamental dwarf bamboo species with high ecological and economic value in China.There was no documentary record of the flowering of P.pygmaeus until 2015,which bloomed in the Bamboo Garden of Nanjing Forestry University.Generally,bamboo plants rarely bear fruit or have a low seed setting rate,but this species has a high seed production.This study explores developmental reasons using anatomical methods.The process of flower bud differentiation and a series of important reproductive development processes including anther wall development,microsporogenesis,megasporogenesis,male and female gametophyte development,and embryonic development were investigated sequentially.Each stamen contained three tetrasporangiate anthers and the development of anther wall was of Monocotyledonous type.The microspores finally matured into 3-celled pollen grains by two successive mitoses.The pistil was composed of three carpels,with an anatropous,tenuinucellate and bitegmic ovule in a single ovary.The formation of embryo sac belonged to Polygonum type.With three mitoses,functional megaspore developed into the embryo sac with eight nuclei within seven cells.The development of stamen and pistil was synchronous in the same floret.The development of embryo followed Grass type and the development of endosperm belonged to Nuclear type.The development of endosperm was earlier than that of embryo.The study enriches basic knowledge of reproductive biology of bamboo plants and is of great fundamental significance to furtherly explore flowering mechanism of P.pygmaeus and to cultivate bamboo plants sustainably.展开更多
[目的]准确了解石斛兰花芽分化规律,研究不同的温度处理对春石斛兰花芽分化和发育的影响,为石斛兰的花期调控提供技术支持。[方法]采用石蜡切片法观察了石斛兰(Dendrobium Spring Snow)花芽的形态发生和结构发育过程,研究了26/21℃、22...[目的]准确了解石斛兰花芽分化规律,研究不同的温度处理对春石斛兰花芽分化和发育的影响,为石斛兰的花期调控提供技术支持。[方法]采用石蜡切片法观察了石斛兰(Dendrobium Spring Snow)花芽的形态发生和结构发育过程,研究了26/21℃、22/17℃、18/13℃处理条件下花芽分化和发育的差异性。[结果]研究表明:石斛兰花芽分化过程可分为7个时期:休眠期、萌动期、花序原基分化期、花蕾原基分化期、萼片原基分化期、花瓣原基分化期、合蕊柱分化期。在高温26/21℃处理条件下,石斛兰不能进行花芽分化,22/17℃处理条件下,需要56 d才能完成花芽分化,在18/13℃条件下,35 d能够完成花芽分化。[结论]持续足够时间的低温是花芽分化的关键,萌动期是一个对温度高度敏感的时期,此时至少经历2周的低温,能够形成花芽,经历高温,则形成高芽。花芽形成后温度高有利于花芽的发育。展开更多
文摘Leaves are of fundamental importance to plants, representing their facility to generate power and are the sensing units of plants towards the environment. An attempt was made to characterize and compare the variations of leaf morphology of various Populus deltoides Bartr. clones by studying the winter buds and other leaf parameters of fully developed leaves. To achieve these objectives, forty-three exotic and indigenous clones ofP. deltoides Bartr. were evaluated for different parameters. On the basis of various morphological characteristics the results reveal that each clone has a distinct color pattern of leaves. Different colors observed in these clones varied from light green through green to dark green. Two distinct lengths of the leaf apex were found, i.e., short and long; as well both acuminate and acute apex types were found. Erratic distribution of serration of leaves was also found. In this study, the morphological traits of leaves provided discriminatory grounds for separating various populations of P. deltoides Bartr. clones. Winter bud studies indicate that different clones vary considerably with regard to shape, color, shape of leaf scars and exudation.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.LY21C160001)Zhejiang Science and TechnologyMajor Program on Agricultural New Variety Breeding(No.2021C02071-4)Natural Science Foundation of Zhejiang Province(LQ17C160005).
文摘Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red soil is the most widely covered soil type in the world,and it is also the most suitable soil type for crape myrtle planting.The flower buds of crape myrtle(Lagerstroemia indica)planted in red soil were employed as experimental materials in this study,and the distinct periods of differentiation were identified using stereomicroscopy and paraffin sectioning.We optimized the steps of dehydration,transparency,embedding,sectioning and staining when employing paraffin sections.When seen under a microscope,this optimization can make the cell structure of paraffin sections obvious,the tissue structure complete,and the staining clear and natural.The flower bud differentiation process is divided into 7 periods based on anatomical observations of the external morphology and internal structure during flower bud differentiation:undifferentiated period,start of differentiation period,inflorescence differentiation period,calyx differentiation period,petal differentiation period,stamen differentiation period,and pistil differentiation period.The differentiation time is concentrated from the end of May to mid-June.Crape myrtle flower bud differentiation is a complicated process,and the specific regulatory mechanism and affecting elements need to be investigated further.
基金supported by the National Natural Science Foundation of China (Grant No. 31870595No. 32001292)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)。
文摘As a woody grass,bamboo has special reproductive habits with an extremely long vegetative phase.Pleioblastus pygmaeus is a kind of ornamental dwarf bamboo species with high ecological and economic value in China.There was no documentary record of the flowering of P.pygmaeus until 2015,which bloomed in the Bamboo Garden of Nanjing Forestry University.Generally,bamboo plants rarely bear fruit or have a low seed setting rate,but this species has a high seed production.This study explores developmental reasons using anatomical methods.The process of flower bud differentiation and a series of important reproductive development processes including anther wall development,microsporogenesis,megasporogenesis,male and female gametophyte development,and embryonic development were investigated sequentially.Each stamen contained three tetrasporangiate anthers and the development of anther wall was of Monocotyledonous type.The microspores finally matured into 3-celled pollen grains by two successive mitoses.The pistil was composed of three carpels,with an anatropous,tenuinucellate and bitegmic ovule in a single ovary.The formation of embryo sac belonged to Polygonum type.With three mitoses,functional megaspore developed into the embryo sac with eight nuclei within seven cells.The development of stamen and pistil was synchronous in the same floret.The development of embryo followed Grass type and the development of endosperm belonged to Nuclear type.The development of endosperm was earlier than that of embryo.The study enriches basic knowledge of reproductive biology of bamboo plants and is of great fundamental significance to furtherly explore flowering mechanism of P.pygmaeus and to cultivate bamboo plants sustainably.
文摘[目的]准确了解石斛兰花芽分化规律,研究不同的温度处理对春石斛兰花芽分化和发育的影响,为石斛兰的花期调控提供技术支持。[方法]采用石蜡切片法观察了石斛兰(Dendrobium Spring Snow)花芽的形态发生和结构发育过程,研究了26/21℃、22/17℃、18/13℃处理条件下花芽分化和发育的差异性。[结果]研究表明:石斛兰花芽分化过程可分为7个时期:休眠期、萌动期、花序原基分化期、花蕾原基分化期、萼片原基分化期、花瓣原基分化期、合蕊柱分化期。在高温26/21℃处理条件下,石斛兰不能进行花芽分化,22/17℃处理条件下,需要56 d才能完成花芽分化,在18/13℃条件下,35 d能够完成花芽分化。[结论]持续足够时间的低温是花芽分化的关键,萌动期是一个对温度高度敏感的时期,此时至少经历2周的低温,能够形成花芽,经历高温,则形成高芽。花芽形成后温度高有利于花芽的发育。
