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61.
Inclusion of IAA in the vase water had little effect on leaf yellowing in cut flowering branches of Alstroemeria pelegrina L. while kinetin delayed leaf yellowing at 10-4M (continuous treatment). Chlorophyll was effectively retained by 10-7M gibberellic acid (GA) in the vase water or by a 20h pulse at 5°C with 10-5/10-4M GA. After 16h of 14C-GA, uptake at 20°C relatively high levels of 14C were found in leaves and low levels in stems and flowers. After this treatment about half of the 14C-GA, in leaves was metabolized into unknown compounds. Corrigendum. Owing to an error in the proofreading process, the article was published incorrectly. The article as it should have been published is presented here.  相似文献   
62.
表油菜素内酯对月季切花保鲜作用的研究   总被引:11,自引:1,他引:11  
本文初步探讨了表油菜素内酯(epiBR)对瓶插月季切花的保鲜作用。与对照(蒸馏水)和基本液(2%蔗糖+500mgL-1柠檬酸+250mgL-8-羟基喹啉+25mgAgNO3)相比,经epiBR处理(基本液+0.1mgL-1epiBR)的月季切花花枝坚挺,蓝变延迟,瓶插寿命延长1-1.5倍。测定有关生理指标表明,epiBR处理对月季切花瓶插花枝前期鲜重的增加及后期的保持有明显作用。并显著延缓花瓣和叶片质膜相对透性的增加,还能使瓶插前期花瓣还原糖含量增加。epiBR处理对花瓣蛋白质和叶片叶绿素含量变化无明显影响,而对花瓣花青素水平下降有轻微的促进作用。  相似文献   
63.
Flowers in the tribe Crotalarieae of the family Fabaceae are generally adapted to bee pollination mechanisms. Molecular systematics have recently provided a major step towards a profound insight into generic relationships, thereby creating the opportunity to re-evaluate the taxonomic and functional significance of flower structure in the tribe, with emphasis on the large genus Crotalaria. A representative sample of flowers from 211 species was dissected to record morphological character states. These data were supplemented from the literature to allow for generalizations for the tribe as a whole. Six structural–functional flower types were identified: (1) pump; (2) gullet; (3) hugging; (4) saddle; (5) tunnel and (6) brush (saddle and tunnel types described here for the first time). Crotalaria uniquely has the brush type, characterized by a rostrate keel, highly dimorphic anthers, stylar trichomes and elaborate callosities on the standard petal. Remarkably, Crotalaria and Bolusia are the only genera of the tribe Crotalarieae with callosities present in all of the species. In other genera, callosities are generally absent or infrequent. Trends towards specialization of pollination syndromes are apparent as assemblages of apomorphic states that co-occur in what we refer to here as “specialized flowers”; individual characters are labile or non-homologous (e.g. callosities) and diagnostically less valuable. Unique combinations of flower characters are often useful to support current generic concepts in Crotalarieae.  相似文献   
64.
The flowers of Erythrina brucei afforded, in addition to known compounds, a new erythrina alkaloid, 8-oxoerythrinine. Its structure was elucidated by spectroscopic investigations as well as by chemical transformations.  相似文献   
65.
广西野生花卉资源的研究   总被引:8,自引:1,他引:8  
记述了广西野生花卉资源的概况 ,5个基本特点和 6个主要类群。同时也对产地的自然环境作了简介 ,并对广西野生花卉的保护和开发提出了建议。广西野生花卉的 5个主要特点是 :花卉种类的丰富性、种质资源的珍贵性、生长基质的特殊性、草本性状的显著性和资源分布的不均性。其 6个主要类群是 :山茶科、杜鹃科、兰科、木兰科、百合科和苦苣苔科。  相似文献   
66.
67.
We investigated the pollination system and movement patterns of pollinators among flowers of the nectarless, monoecious vine Akebia quinata in natural populations and experimental floral arrays. Female flowers did not offer any rewards for pollinators and were larger than male flowers. Pollinators of A.quinata , such as small solitary bees and hoverflies, clearly discriminated between male and female flowers. Hoverflies always visited male flowers and rarely visited female flowers. In contrast, solitary bees tended to visit female flowers first when entering the array, but then switched to male flowers within the same foraging bout. This tendency disappeared when the sepal size of female flowers was experimentally reduced to the size of male flowers. Thus, observed non-randomness in flower choice by solitary bees may be caused by female>male sexual dimorphism and may increase the chance of cross-pollination and lower the probability of geitonogamous pollination in a single visit to a plant. Therefore, floral sexual dimorphism in A.quinata is considered to be an adaptation for deceptive pollination associated with discriminating pollinators.  相似文献   
68.
为初步探究丛枝菌根(arbuscularmycorrhizal,AM)真菌促进百合生长并延长瓶插过程中切花观赏期的作用机制,于温室盆栽条件下对百合Lilium brownii进行摩西斗管囊霉Funneliformis mosseae和变形球囊霉Glomusversiforme单一接种或者共同双接种处理。结果表明,共同接种F.mosseae和G.versiforme的百合地上部干重和地下部干重均显著高于不接种对照,分别增加了60%和58%。与不接种对照相比,接种F. mosseae和G. versiforme处理的百合根尖数、根系长度、分叉数、表面积和根系体积分别比对照增加123%、128%、182%、118%和232%。切花瓶插期间,接种AM真菌处理的百合切花水分平衡值和鲜重变化率显著高于对照处理;乙烯释放速率和呼吸速率显著低于对照,瓶插5d时达到乙烯峰值5.4μL/*g·h (FW)+,共同接种F. mosseae和G. versiforme处理的百合切花乙烯释放速率比对照降低30%;呼吸速率则在瓶插1d时达到峰值0.7μL/*g·h (FW)+,共同接种比对照降低37%;百合花瓣内超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、可溶性糖含量和可溶性蛋白含量比对照分别提高19%、32%、52%和26%。百合花瓣内N、P、K、Mg、Ca、Fe和Zn含量均显著高于不接种对照处理,Mn和Cr含量则低于对照;共同接种处理的百合瓶插寿命增加了3d,最佳观赏时间比对照延长2d。结论认为共同接种F. mosseae和G. versiforme处理更加有效地改善切花花枝的水分平衡、营养状况与生理代谢,控制衰老激素的合成,从而延长百合切花的瓶插寿命和最佳观赏期。  相似文献   
69.
Gynomonoecy is the sexual system in which female and bisexual flowers occur on the same plant. This system has received little attention despite the considerable work on other plant sexual systems in the past few decades. Our study examines one hypothesized advantage of having two flower types on a plant, namely that this arrangement permits flexibility in allocation of resources to male and female reproductive functions. We examined 16 species of Aster (Asteraceae), a genus of gynomonoecious, perennial herbs. Plants in this genus produce heads consisting of a whorl of female flowers around a cluster of bisexual flowers. Among field-grown plants we found no evidence that plant size, date, position of heads, rainfall, or shade influenced the proportion of female flowers. A series of greenhouse experiments likewise revealed no large or consistent effects of light, nutrients, or position of heads on the proportion of ray flowers. While floral ratios proved very stable in the face of environmental and physiological variables, they exhibited significant variation among plants and among sibships in most species. We conclude that the presence of two flower types in gynomonoecious asters is not advantageous in permitting flexibility in allocation of resources to male and female functions. We believe that the advantage of the female flowers in aster heads lies either in reducing pollen-pistil interference or in attracting pollinators.  相似文献   
70.
进化发育生物学的一个重要任务就是揭示形态多样性的分子基础,该领域的研究包含形态、形态发育相关基因和形态所属类群等三个要素。花/花序是进化发育生物学研究的首要对象,系统发育重建和个体发育剖析的结合将促进认知花的形态进化。发育相关基因的进化表现为等位基因遗传或表观遗传的突变,基因家族生与死的进化,不同基因组拥有独特的基因。运用形态学或序列分析方法很大程度揭示了禾本科植物花进化过程中的基因进化。试从学科问题、思路方法以及具体例子介绍植物进化发育生物学。  相似文献   
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