黄毛草莓花粉活力及柱头可授性测定

为了研究黄毛草莓的开花生物学特性,观测黄毛草莓的散粉规律和繁育系统,并以不同时期的花蕾为试材,用不同方法测定花粉的萌发率和柱头可授性。结果表明:黄毛草莓的单朵花期为2d,散粉时间为每天9∶30～17∶00,在12∶00～14∶00达到顶峰。黄毛草莓的花粉在开花盛期活力最大,其它时期均较低或没有活力。柱头可授性在开花初期和盛花中期达到顶峰,持续到末花期仍具有一定的可授性。     

Genetics of anther indehiscence with exerted stigmas and its application in hybrid rice breeding

Complete indehiscence of anthers accompanied with exerted stigmas outside the hull could be useful in hybrid rice breeding if the genetics and possible environmental effects are well understood. Studies were undertaken to identify the sources, confirm the mode of inheritance, and examine the possible environmental effects and potential application of anther indehiscence with exerted stigmas in hybrid rice breeding. Direct and reciprocal crosses were made between Jasmine 85, selected interspecific and intersubspecific lines and two wide compatibility varieties. The resulting F₁ progenies were evaluated for their expression of anther indehiscence and exerted stigmas. Expression of anther indehiscence with exerted stigmas by both direct and reciprocal crosses suggested no effect of cytoplasmic factors on the expression of the trait. Segregation analysis supported the 7:1 (indehiscence:dehiscence) mode of inheritance. Temperature and relative humidity could not modulate the fertility/sterility status of anther indehiscent plants. Utilization of anther indehiscence with exerted stigmas in hybrid rice breeding was hindered by trait fixation and propagation.     

暗紫贝母花器官特征及有性繁育系统研究

采用田间试验与显微镜检相结合的方法,对漳县人工栽培的暗紫贝母花器构造和传粉生物学进行研究,旨在揭示其花器官特征和有性繁育系统,为暗紫贝母的育种提供科学依据。结果表明,经鳞茎播种栽培3年的暗紫贝母植株单花顶生,偶见2花,花两性,初现花蕾绿色,花暗紫色,有淡黄色格纹,开花期5-6月,单花寿命6~8 d,花钟形,同被花,花被6,2轮,离生雄蕊6枚,5枚紧围雌蕊,1枚外围,子房上位,柱头3裂,短裂片外露,毛状有分泌物。开花前柱头高于雄蕊,开放后雄蕊高出柱头,开花当天花粉量最大,活力最高并维持3 d时间。花被长1.5 cm的绿蕾柱头已具较强可受性。花药开裂与强柱头可受性同步,但后者持续期更长(6 d以上)。单花花粉数约6000粒、胚珠数在160颗以上,花粉胚珠比(P/O)37.5,杂交指数(OCI)为4。传粉媒介为风媒和虫媒,访花者为蜂类、蝇类和蜘蛛,但数量极少,有性繁育系统应属于部分自交亲和,异交,需要传粉者。     

Elimination of Citrus psorosis virus by somatic embryogenesis from stigma and style cultures

Somatic embryogenesis was used to eliminate Citrus psorosis virus (CPsV) from three citrus species (common mandarin, sweet orange and Dweet tangor), all of which regenerated somatic embryos with different embryogenic potential from stigma and style explants. CPsV was detected by double antibody sandwich‐indirect‐enzyme‐linked immunosorbent assay (DASI-ELISA) in explants and embryogenic callus, but was not detected in any of the plants obtained from somatic embryos, even 24 months after regeneration. Loss of juvenile characters (disappearance of thorns) was observed in the first year of growth and was retained in plants propagated by grafting from thornless stems. Somatic embryogenesis appears to be a very promising technique for the production of healthy citrus stocks.     

Rain effect on pollen–stigma adhesion and fertilization in almond

The fact that rainy weather negatively affects production in almond is well-known by growers. However, as far as we know, no previous study has been carried out in this species to determine if the rain is able to wash off pollen grains from the stigma surface and consequently affect fertilization efficiency. To answer this question, flowers of the self-compatible almond cultivar ‘Antoñeta’ were emasculated on branches of trees in the field, pollinated by hand with pollen of the cultivar ‘Marcona’, and sprayed with water to simulate the rain effect at 4, 8, 24 and 48 h after pollination. A control for which no treatment was applied was also included in the assay. Seven days after spraying the flowers, the number of germinated pollen grains on the stigma was recorded in 10 pistils for each treatment by fluorescent microscopic observation. In addition, for each treatment the initial and final fruit set were determined at 30 and 60 days after pollination, respectively. The following year additional assays were performed in the field and in the laboratory in order to complete the study with earlier treatment times. Thus, an assay of rain simulation in the field at 0 and 2 h, and other consisting on immersing a branch with flowers and shaking it in a water container in the laboratory at 0, 30, 60 and 120 min after pollination were performed. One sample more was immersed, shaken, then pollinated and again immersed and shaken. The results from field assays showed that adhesion of pollen grains to the stigma was very quick and strong, and the treatments did not significantly affect pollen–stigma adhesion and subsequent fruit set. On the other hand, laboratory results showed that all washing treatments decreased the number of germinated pollen grains on the stigma, mainly when the flowers were immersed before pollination. In conclusion, the results showed that the simulated rain was not able to completely wash off pollen grains from the stigma surface, although it seems to affect adhesion in forthcoming pollinations.     

油茶的传粉生物学特性

油茶是一种秋冬季开花的重要油料植物.为了探讨油茶结实率低的主要原因,从而为改造油茶低产林以提高油茶结实率提供一些有用的数据和参考资料,从花粉限制和传粉生物学的角度进行研究,对油茶花粉的活力、花粉的可育性及花粉量、花粉量与胚珠数的比率(P/O)、柱头可授性、花蜜量及花蜜含糖量进行了测定.结果表明:在开花8 h后油茶花粉的活力达到最大,平均为(71.0%士0.056 oA);花粉的可育率为(93.97 oA士1.62%)(n=30);柱头可授性在开花第2天达到最大,每朵花的花蜜量平均为(421.2:E14.0)uL(n=30),其含糖量为(29.12%±0.94%)P/O为(17 675.08+302.II)(n=20).根据Cruden(1977)的标准,P/O之比值为(17 675.08±302.11),测定结果表明了油茶的交配系统为专性异交型.     

不同授粉处理对百合花粉萌发生长及坐果率的影响

利用荧光显微镜观察了‘Snow Queen’×细叶百合和‘Snow Queen’בPollyanna’不同授粉处理对花粉管萌发和生长的影响。结果显示:两种组合中,常规授粉花粉萌发率最高,但坐果率较低;常规授粉、切割柱头授粉均未观察到花粉管延伸至花柱道中;切割花柱授粉,坐果率最高,而且用胚培养可以获得幼苗,表明受精前障碍同时存在于柱头和花柱上部组织内。两个组合,相同的授粉处理,均表现为切割并涂抹柱头粘液花粉萌发率和坐果率高于未涂抹粘液。‘Snow Queen’×细叶百合的花粉萌发率及坐果率相对高于‘Snow Queen’בPollyanna’。     

A0A对梨花期花朵生活力和花后坐果率的影响

以不同浓度（0、1、5、10、15 mg/L）的氨基氧乙酸（AOA）对 “翠冠”大蕾期梨花及“黄花”花粉进行处理,测定花期花朵生活力、花朵柱头活性及花粉活力的生理变化,并以最佳浓度进行液体授粉,测定其花后坐果率。结果表明,在“翠冠”梨整个花期中,与对照相比,不同浓度的AOA均能降低梨花的萎蔫速率,并使花柱头保持较长时间的活力,其中15mg/L AOA延长花期的效果最佳。在以最佳浓度进行液体授粉后,与对照相比花序坐果率和花朵座果率均提高。     

籼型光温敏核不育系柱头性状表现

以5个籼型光温敏核不育系为材料,分别对其柱头外露率、柱头长度、柱头宽度、柱头面积和柱头体积以及柱头活力等指标进行了观察测定,并以柱头外露率作为首要指标进行排序,得出了参试光温敏核不育系材料柱头综合性状表现结果,依次为F168S、信矮10-4S、矮青34S、广占63-4S、信丰9826S。