大花蕙兰与国兰花粉活力及柱头可授性分析

花粉和柱头具有较高的活力是保证杂交育种工作有效开展的关键。采用氯化三苯基四氮唑（TTC）,碘,碘化钾（I2-KI）和醋酸洋红等3种染色法测定了大花蕙兰Cymbidium hybridum和国兰不同种和品种的花粉活力,用联苯胺-过氧化氢法测定了大花蕙兰和国兰部分品种的柱头可授性并观察柱头分泌黏液情况。研究结果表明：碘一碘化钾染色法和醋酸洋红染色法都不适合大花蕙兰和国兰花粉活性的测定,TTC染色法是观察花粉活力最直观的方法。大花蕙兰与国兰的花粉活力是随着开放时间的延长,经历从弱变强再变弱的过程,大花蕙兰和国兰的花粉分别在开后25～35d和15～25d活力最佳。大花蕙兰和国兰的柱头在整个花期中均具有一定的可授性,其中大花蕙兰在20～40d内的可授性最强,45d以后其柱头可授性逐渐减弱。国兰在15～25d内的柱头可授性最强,30d以后柱头的可授性逐渐消失。总体而言,整个柱头可授性是随着时间的变化从弱到强再到弱的一个过程。     

美味猕猴桃‘徐香’与长果猕猴桃远缘杂交亲和性的解剖学研究

 以美味猕猴桃（Actinidia chinensis var. diliciosa）‘徐香’与长果猕猴桃（A. longicarpa）进行远缘杂交,利用荧光显微镜观察了花粉管行为,常规石蜡切片法观察了受精及胚发育过程的差异,统计了杂交当代种子数量和坐果率。结果表明：种间杂交长果猕猴桃的花粉粒能在美味猕猴桃‘徐香’柱头的乳突细胞表面萌发、生长,但生长速度比对照缓慢;花粉管在花柱中生长时出现波纹状弯曲、停止生长、胼胝质沿管壁不规则沉积等现象;受精过程延迟;胚胎发育出现异常;坐果率较低。种子总数明显少于种内杂交和种内自然授粉的数量,但正常种子的质量与后者大致相同。     

结球甘蓝花粉蛋白延伸因子基因的克隆及其序列分析

 以结球甘蓝（Brassica oleracea L. var. capitata L.）E1花粉为试材,对萌发前后的花粉总蛋白进行双向电泳及差异蛋白质谱分析,发现延伸因子BoEF-Tu蛋白在花粉萌发后较萌发前表达上调。利用同源克隆得到甘蓝BoEF-Tu基因的全长cDNA序列,其长度为1 728 bp,具有一个完整开放阅读框（ORF）,位于112 ~ 1 473 bp处,编码453个氨基酸残基,预测分子量为49.17 kD,等电点为6.52。生物信息学分析表明：BoEF-Tu蛋白含有9个α–螺旋结构,18个β–折叠结构,不含信号肽和跨膜区,在106 ~ 121位氨基酸残基处有1个GTP结合区域（DKAPEEKKRGITIATA）。氨基酸同源性分析表明,BoEF-Tu与拟南芥EF-TuM同源性较高,达到93%;系统进化分析表明,BoEF-Tu与拟南芥EF-Tu的亲缘关系最近。     

烤烟不同花期花粉数量和花粉活力研究

 为指导烤烟(Nicotiana tobacum L.)雄性不育系和杂交种种子生产中花粉采集和介质花粉应用,实现精量化授粉,本研究以NC 297, K 326, 红花大金元、云烟85, 云烟87和云烟97共6个烤烟品种为试验材料,研究了各品种不同花期的花药大小、1朵花生成花粉数量、1g花粉含有花粉粒数量和花粉活力的变化规律。结果显示,烤烟花药长为3.52～4.55mm,宽为1.55～2.54mm,1朵花生成花粉数量为2.0×105～3.4×10 5粒,1g花粉含有花粉粒数量为1.2×108～1.63×108粒,花粉活力为70.4%～91.4%。各烤烟品种的花药大小、1朵花生成花粉数量和花粉活力均随着花期的延长逐渐降低,并存在品种间差异,其中,花粉活力在中心花开放后第0～40天内大于80%,第40～45天明显降低,因此,花粉采集时间以从中心花开放起持续至中心花开放后的40d为佳,每株父本可采摘花朵500朵左右,花粉产量约1g,理论上可供10000朵母本花授粉。     

花粉萌发与花粉管生长的信号调控机制

花粉萌发与花粉管生长是植物生殖过程中的重要生理现象,它关系到植物能否正常完成受精过程.该过程涉及大量的信号通路介导,包括小G蛋白调控、磷酸肌醇信号调控及Ca2+信号通路等.这些信号通路直接或间接影响着花粉萌发与生长过程的各个方面,包括花粉管的极性生长及细胞骨架变化等.综述了不同信号通路对花粉萌发与生长过程的影响,重点关注各个信号分子的作用基础和原理,旨在更深入地展现花粉萌发全过程中信号通路调控下的胞内全景,结合现有试验结果,提供关于花粉萌发与生长的新模式.     

东北蒲公英核型分析与减数分裂的细胞遗传学观察

对东北蒲公英(Taraxacum.ohwianum Kitam.)染色体的核型和花粉母细胞减数分裂行为进行了研究.结果表明,东北蒲公英染色体为二倍体,染色体数2n=16,核型公式K(2n)=2x=16=10 m+6 sm,属于2A型,并观察到有随体存在.东北蒲公英的造孢细胞存在大量染色体的特殊情况可能是花粉母细胞的一种独特形成途径.此外在终变期只观察到单价体,在中后期Ⅱ染色体拉向两极不明显,这与在高等植物中描述的减数分裂行为并不完全一致.东北蒲公英四分体为非连续型胞质分离,产生了均匀一致的小孢予.     

药用植物桔梗的育种研究进展

介绍了药用植物桔梗在育种方面的研究进展,包括桔梗的花粉特性、种质资源、育种方法以及育成的品种等方面.     

Broadening the genetic base of lentil cultivars through inter‐sub‐specific and interspecific crosses of Lens taxa

Wild Lens taxa are invaluable sources of useful traits for broadening genetic base of cultivated lentil. Nine inter‐sub‐specific and interspecific crosses were made successfully between cultivated (Lens culinaris ssp. culinaris) and wild lentils (L. culinaris ssp. orientalis, odemensis, lamottei and ervoides). The effect of species groups, day length and temperature on crossability in lentils was evident under normal winter sowing in New Delhi and in summer Himalayan nursery at Sangla in Himachal Pradesh, India, although pollen fertility assessed in all the cross‐combinations showed no significant variation. True hybridity of nine inter‐sub‐specific and interspecific crosses was confirmed through morphological and molecular (ISSR) markers, in which three of 120 primers could confirm the hybridity of all the crosses. All cross‐combinations were also studied for important quantitative traits related to yield. The range, mean and coefficient of variation were estimated in parental lines, F₁ and F₂ generations to determine the extent of variability generated in cultivated lentils through the introgression of genes from wild L. taxa. A high level of heterosis was observed in F₁ crosses for important traits studied. Substantially higher variations for seed yield and its attributing traits were exhibited in F₂ generations indicating transgressive segregation. The results of the present investigation revealed that wild L. taxa can be successfully exploited for lentil improvement programmes, and the variations generated could be easily utilized for broadening the genetic base of cultivated lentil gene pool for improving the yield as well as wider adaptation.     

Reproductive development response to high daytime temperature in field pea

Flowering plants are highly sensitive to heat stress during reproductive phase, which covers development from floral initiation to seed maturity. The objectives of this study were to diagnose high temperature effects on pollen production and morphology, production of reactive oxygen species (ROS) in pollen grains and ovules in pea cultivar “CDC Golden.” This study also investigated timing and duration of heat exposure at specific developmental stages of floral buds, open flowers and early set pods on flower and pod abortion, seed development and seed yield in “CDC Golden” and a second cultivar “CDC Sage.” The experiments were conducted in growth chambers with two temperature regimes (24/18°C and 35/18°C day/night temperature for 4–14 days) during reproductive development. Heat stress reduced the number of pollen grains per anther, induced smaller pollen grains and increased ROS production in pollen grains, but it did not affect ROS accumulation in ovules and ovule number per ovary. Heat exposure when young floral buds were visible at the first reproductive node was more detrimental to flower retention, seed set, pod development and seed yield compared to heat exposure started later when flowers at the second reproductive node were fully open.     

柱花草花粉活力的测定方法

利用6种常用花粉活力测定方法对柱花草花粉活力进行测定，并筛选出各方法的最佳配方。结果表明：以离体萌发法为最佳，最适培养基：10%蔗糖、10% PEG-6000(聚乙二醇)、0.01% H3BO3、0.03% CaCl2·2H2O、0.01% KNO3，pH 6.5，柱花草花粉在该培养基上30℃条件下培养10 min，萌发率可达84.03%。0.5% I2＋1.5% KI的碘-碘化钾染色效果好，色差明显，较离体萌发法测定值偏高，但差异不显著，可选作简单快速测定法；FDA(荧光素二醋酸脂)染色法、醋酸洋红染色