In an effort to provide some information relevant to the molecular mechanism of genic male sterility in plants, BcMF3 gene that encodes a pectin methylesterase was isolated from the fertile B line of Chinese cabbage-p...In an effort to provide some information relevant to the molecular mechanism of genic male sterility in plants, BcMF3 gene that encodes a pectin methylesterase was isolated from the fertile B line of Chinese cabbage-pak-choi （Brassica rapa ssp. chinensis, syn. B. campestris ssp. chinensis）. In the present paper, a 455-bp antisense cDNA fragment of BcMF3 was introduced to binary vector pB1121, and then was mobilized into Agrobacterium tumefaciens strain LBA4404. The A. tumefaciens harboring the BcMF3 antisense fragment was transformed to Arabidopsis thaliana by floral dip. Scanning electronic microscopy examination demonstrated that 47.8% of BcMF3 antisense pollen grains exhibited abnormal shape, which might lead to decreased germination of pollens, suggesting that the product of BcMF3 gene plays an important role during microsporogenesis. The evidence on burst of 45.7% of BcMF3 antisense pollen tubes in vitro and a majority of BcMF3 antisense pollens restricted within the stigmatic tissue revealed that BcMF3 is involved in aiding the growth of pollen tubes. The results suggest that BcMF3 acts at both stages of microsporogensis and pollen tube growth.展开更多
Microsporogenesis and flower development in Eucalyptus urophylla × E. grandis were examined using chromosome tableting to provide a method to predict the meiotic stages in this species. Although microsporogenesis...Microsporogenesis and flower development in Eucalyptus urophylla × E. grandis were examined using chromosome tableting to provide a method to predict the meiotic stages in this species. Although microsporogenesis was normal, cytokinesis during meiosis of pollen mother cells occurred simultaneously, with strong asynchronism observed in the two different lengths of stamens in a flower bud. In a single flower, the developmental period of microsporogenesis in anthers on the longer stamens was always ahead of those on the shorter stamens. Flower development was also asynchronous at different locations on a branch. Flower buds on the upper side of the branch were larger in diameter than those on the lower side. In addition, a correlation was observed between microsporogenesis development and flower bud diameter growth. The pachy- tene stage was first observed when the diameter of the flower buds increased to 3.0 mm, and the majority of the meiotic stages were observed when bud diameters ranged from 3.5 to 5.0 mm. This study showed that the developmental stages of microsporogenesis in Eucalyptus urophylla × E. grandis could be distinguished readily, which may be applicable to future breeding studies.展开更多
This study addressed the differences in microsporogenesis between male sterile and fertile lines of Chinese pink. The microsporogenesis processes of male sterile and fertile lines were histologically examined in squas...This study addressed the differences in microsporogenesis between male sterile and fertile lines of Chinese pink. The microsporogenesis processes of male sterile and fertile lines were histologically examined in squashed pollen grains and in paraffin embedded sections. A stable male-sterile line （H-37B） was obtained following six generations of inbreeding in a self-fertile line, followed by two generations of backcrossing. In the corresponding fertile line, development of the mature pollen grains was followed through the initiation of the sporogenous cell, microsporocyte formation, and the tetrad developmental period. In the male-sterile line, abortion of the developing pollen grains was observed to take place at various stages, namely, sporogenous cell growth, mother cell meiosis, and tetrad transformation to the uninuclear state. The pollen grains of the fertile line were spheroid, turgid, and viable. By contrast, the male-sterile line produced pollen that was irregular in shape, empty, and nonviable. The abortion of the microspore in the male-sterile line appeared to relate to abnormal growth of the tapetum layer.展开更多
The microsporogenesis and male gametophyte development of Euphorbia pulcherrima were studied with paraffin section method. The results showed that the anther of Euphorbia pulcherrima had four chambers. The development...The microsporogenesis and male gametophyte development of Euphorbia pulcherrima were studied with paraffin section method. The results showed that the anther of Euphorbia pulcherrima had four chambers. The development of anther wall was dicotyledonous type; its wall consisted of epidermis, endothecium, middle layer and tapetum. The mature male gametophyte development experienced seven major stages as the followings： archesporial cells, aporgenous cells, microspore mother cells, tetrads of microspores （tetrahedral）, uninucleate microspores, 2-uncleate pollens and 2-celled pollen stage. The anther wall varied with the pollen development： the epidermis of anther ruptures at the anther mature stage; the middle layer disappears at tetrad stage; the endothelium became fibrous layer at the anther mature stage; the tapetum （glandular） was the most development at the microspore mother cells stage and disappeared at anther mature stage. The abnormal anther development was observed simultaneously.展开更多
光果姜[Zingiber montanum(J.Koenig)Link ex A.Dietr]为姜科姜属多年生草本植物,具有殷红的锥形花序,极具观赏价值,其花序轴较短且柔软易断,可通过杂交手段进行品种改良。此外,姜科植物的系统进化关系一直存在争议,目前关于光果姜生殖...光果姜[Zingiber montanum(J.Koenig)Link ex A.Dietr]为姜科姜属多年生草本植物,具有殷红的锥形花序,极具观赏价值,其花序轴较短且柔软易断,可通过杂交手段进行品种改良。此外,姜科植物的系统进化关系一直存在争议,目前关于光果姜生殖生物学研究相对缺乏。为了促进杂交育种工作的顺利进行以及为姜科植物系统进化提供新的证据,该研究以石蜡切片法为主要研究方法,进一步结合整体压片法和半薄切片法,观察了姜科姜属植物光果姜的大小孢子和雌雄配子体的发育过程,旨在深入了解光果姜的生殖生物学解剖学特征,为姜科植物保育工作提供理论依据。结果表明:①光果姜花药包含2室,花药壁的形成方式属于基本型,具有变形绒毡层;②小孢子母细胞减数分裂类型为连续型,四分体包含左右对称型,直线型和T型,成熟花粉粒为2-细胞型;③胚珠的类型为倒生胚珠,具有双珠被和厚珠心,雌配子体发育类型为蓼型;④揭示了雌雄配子体发育的对应关系,二者成熟时间同步,但雄蕊进入减数分裂时期比雌蕊早。首次发现光果姜花药壁中的绒毡层类型为变形绒毡层,这与前人报道的其他姜科植物的特征不同。研究结果可为姜科植物繁育工作及其系统分类提供有力的科学依据。展开更多
基金the National Natural Science Foundation of China （30370975） the Key Scitechnology Project of Zhejiang Province （2005C 12019- 02） the Natural Science Foundation of Zhejiang Province, China （Y304180）.
文摘In an effort to provide some information relevant to the molecular mechanism of genic male sterility in plants, BcMF3 gene that encodes a pectin methylesterase was isolated from the fertile B line of Chinese cabbage-pak-choi （Brassica rapa ssp. chinensis, syn. B. campestris ssp. chinensis）. In the present paper, a 455-bp antisense cDNA fragment of BcMF3 was introduced to binary vector pB1121, and then was mobilized into Agrobacterium tumefaciens strain LBA4404. The A. tumefaciens harboring the BcMF3 antisense fragment was transformed to Arabidopsis thaliana by floral dip. Scanning electronic microscopy examination demonstrated that 47.8% of BcMF3 antisense pollen grains exhibited abnormal shape, which might lead to decreased germination of pollens, suggesting that the product of BcMF3 gene plays an important role during microsporogenesis. The evidence on burst of 45.7% of BcMF3 antisense pollen tubes in vitro and a majority of BcMF3 antisense pollens restricted within the stigmatic tissue revealed that BcMF3 is involved in aiding the growth of pollen tubes. The results suggest that BcMF3 acts at both stages of microsporogensis and pollen tube growth.
基金financially supported by the Special Fund for Forest Scientific Research in the Public Welfare(201404113)the 111 Project(B13007)the Program for Changjiang Scholars and Innovative Research Team in University(IRT13047)
文摘Microsporogenesis and flower development in Eucalyptus urophylla × E. grandis were examined using chromosome tableting to provide a method to predict the meiotic stages in this species. Although microsporogenesis was normal, cytokinesis during meiosis of pollen mother cells occurred simultaneously, with strong asynchronism observed in the two different lengths of stamens in a flower bud. In a single flower, the developmental period of microsporogenesis in anthers on the longer stamens was always ahead of those on the shorter stamens. Flower development was also asynchronous at different locations on a branch. Flower buds on the upper side of the branch were larger in diameter than those on the lower side. In addition, a correlation was observed between microsporogenesis development and flower bud diameter growth. The pachy- tene stage was first observed when the diameter of the flower buds increased to 3.0 mm, and the majority of the meiotic stages were observed when bud diameters ranged from 3.5 to 5.0 mm. This study showed that the developmental stages of microsporogenesis in Eucalyptus urophylla × E. grandis could be distinguished readily, which may be applicable to future breeding studies.
文摘This study addressed the differences in microsporogenesis between male sterile and fertile lines of Chinese pink. The microsporogenesis processes of male sterile and fertile lines were histologically examined in squashed pollen grains and in paraffin embedded sections. A stable male-sterile line （H-37B） was obtained following six generations of inbreeding in a self-fertile line, followed by two generations of backcrossing. In the corresponding fertile line, development of the mature pollen grains was followed through the initiation of the sporogenous cell, microsporocyte formation, and the tetrad developmental period. In the male-sterile line, abortion of the developing pollen grains was observed to take place at various stages, namely, sporogenous cell growth, mother cell meiosis, and tetrad transformation to the uninuclear state. The pollen grains of the fertile line were spheroid, turgid, and viable. By contrast, the male-sterile line produced pollen that was irregular in shape, empty, and nonviable. The abortion of the microspore in the male-sterile line appeared to relate to abnormal growth of the tapetum layer.
文摘The microsporogenesis and male gametophyte development of Euphorbia pulcherrima were studied with paraffin section method. The results showed that the anther of Euphorbia pulcherrima had four chambers. The development of anther wall was dicotyledonous type; its wall consisted of epidermis, endothecium, middle layer and tapetum. The mature male gametophyte development experienced seven major stages as the followings： archesporial cells, aporgenous cells, microspore mother cells, tetrads of microspores （tetrahedral）, uninucleate microspores, 2-uncleate pollens and 2-celled pollen stage. The anther wall varied with the pollen development： the epidermis of anther ruptures at the anther mature stage; the middle layer disappears at tetrad stage; the endothelium became fibrous layer at the anther mature stage; the tapetum （glandular） was the most development at the microspore mother cells stage and disappeared at anther mature stage. The abnormal anther development was observed simultaneously.
文摘光果姜[Zingiber montanum(J.Koenig)Link ex A.Dietr]为姜科姜属多年生草本植物,具有殷红的锥形花序,极具观赏价值,其花序轴较短且柔软易断,可通过杂交手段进行品种改良。此外,姜科植物的系统进化关系一直存在争议,目前关于光果姜生殖生物学研究相对缺乏。为了促进杂交育种工作的顺利进行以及为姜科植物系统进化提供新的证据,该研究以石蜡切片法为主要研究方法,进一步结合整体压片法和半薄切片法,观察了姜科姜属植物光果姜的大小孢子和雌雄配子体的发育过程,旨在深入了解光果姜的生殖生物学解剖学特征,为姜科植物保育工作提供理论依据。结果表明:①光果姜花药包含2室,花药壁的形成方式属于基本型,具有变形绒毡层;②小孢子母细胞减数分裂类型为连续型,四分体包含左右对称型,直线型和T型,成熟花粉粒为2-细胞型;③胚珠的类型为倒生胚珠,具有双珠被和厚珠心,雌配子体发育类型为蓼型;④揭示了雌雄配子体发育的对应关系,二者成熟时间同步,但雄蕊进入减数分裂时期比雌蕊早。首次发现光果姜花药壁中的绒毡层类型为变形绒毡层,这与前人报道的其他姜科植物的特征不同。研究结果可为姜科植物繁育工作及其系统分类提供有力的科学依据。
