【作者】 李川；

【导师】 辜夕容； 姚小华；

【作者基本信息】 西南大学 ， 森林培育， 2012， 硕士

【摘要】 薄壳山核桃是一种原产于墨西哥北部和美国南部的落叶乔木,其果实和树体的利用价值颇高,目前受到广大消费者和种植户的好评。本文对6个主要薄壳山核桃无性系开花物候及花粉特性进行了研究和分析,研究内容包括6个薄壳山核桃无性系开花物候、花粉形态、花粉活力、花粉储藏性及杂交授粉等方面,以期为种植园的品种配置、杂交育种提供理论依据,研究得出了如下结论。薄壳山核桃不同无性系雌雄花开花物候差异明显,6个无性系间雌花差异最长为10d,差异最短为2d；6个无性系间雄花差异最长为9d,差异最短为1d。不同年份同一无性系在雌雄花开花物候存在一定的差异,但在不同年份开花的先后次序却相对稳定。同一薄壳山核桃无性系不同地点雌雄花开花时间存在显著的差异,对于无性系104号雌花而言,三地始花期最早的是建德,为4月27日,最晚的是安吉,为5月3日,前后相差7d；对于雄花而言,建德散粉始期为5月10日、安吉散粉始期为5月15日、余杭散粉始期为5月12日,三地散粉持续天数介于8～10d左右,散粉盛期持续天数介于5～6d左右。同一无性系不同树冠层、不同方向雌雄花开花物候不一致,对雌花而言,东、南、西、北4个方位开花时间存在细微的差异,东、南2个方位的雌花比西、北方位早1d左右；对雄花而言,东、西、南、北4个方位的开花物候差异不明显,而树冠上、下2层的雄花散粉时间有差异,树冠上层明显比下层早1d左右。6个薄壳山核桃无性系雌花开放数量、雄花序数存在显著差异(P<0.05)。对供试的6个薄壳山核桃无性系花粉进行电子显微镜扫描观测,6个无性系花粉大小属于中等,形状为扁球形(无性系104号为近球形)；花粉粒都具有三个萌发孔,均匀分布在赤道面上。6个无性系花粉赤道面观均呈椭圆形；无性系5号、21号、27号和104号极面观呈近圆形,而无性系28号和35号极面观呈近三角形；6个薄壳山核桃无性系花粉表面均呈颗粒状纹饰,均匀分布着颗粒状的突起,其中无性系21号和27号花粉表面颗粒状分布密集,无性系5号和28号花粉表面颗粒状分布稀疏,无性系35号和104号花粉表面颗粒状分布介于二者之间。对6个薄壳山核桃无性系花粉系统聚类分析结果表明,聚为一类的无性系试验所观测测量的9个指标极为的接近,如无性系35号和104号、21号和27号、5号和28号,从孢粉学方面反映了亲缘关系的远近。经单因数方差分析可知,同一薄壳山核桃无性系不同处理方式下收集的花粉活力均达到了显著性差异(P<0.05),总体表现为干燥剂处理后收集的花粉活力≈阴干处理后收集的花粉活力>30℃恒温干燥处理后收集的花粉活力>日照干燥处理后收集的花粉活力；同一薄壳山核桃无性系不同散粉时期采集的花粉活力均达到了显著性差异(P<0.05)。无性系5号、27号、35号花粉活力均表现出,散粉盛期>散粉始期>散粉末期；同一薄壳山核桃无性系阴干24h、48h、72h后收集的花粉活力均达到了显著性差异(P<0.05)。无性系5号、27号、35号花粉活力均表现出,24h后收集的花粉活力>48h后收集的花粉活力>72h后收集的花粉活力。4种不同的储藏条件(室温、0～5℃、-20℃和-79℃储藏条件)对薄壳山核桃无性系花粉活力存在显著的影响。在室温条件下,3个无性系(无性系5号、27号、35号)花粉活力在16d时就已经很低,到储藏第30d时,3个无性系花粉基本尚失了活力。在0～5℃条件下,3个无性系花粉在储藏第90d时花粉活力就已经下降到20%以下,但其中无性系35号最耐储藏,在180d时花粉活力仍在10%以上。在-20℃和-79℃低温储藏条件下,3个无性系花粉活力储藏时间最长,其中超低温-79℃比低温-20℃储藏条件下,花粉活力耐储藏性更强,在储藏270d时,超低温-79℃条件下,3个无性系花粉活力在22%-28%之间；低温-20℃条件下,3个无性系花粉活力在13%～22%之间。对同一母本而言,不同父本与之杂交授粉是存在差异性的,无性系21号、28号等2个无性系与3个授粉无性系(5号、21号、35号)中的35号的亲和性最高,而无性系104号与无性系5号亲和性最高。对同一父本而言,无性系5号分别对3个母本人工授粉亲和力最高的是无性系21号；无性系27号分别对3个母本人工授粉亲和力最高的是无性系21号；无性系35号分别对3个母本人工授粉亲和力最高的是无性系21号。更多还原

【Abstract】 Carya illinoensis is deciduous tree that is originated in Northern Mexico and Southern United States. As the fruits and trees are of high value, they are highly praised among the consumers and growers. In order to provide theory basis for varieties configuration and crossbreeding in plantation, this paper mainly analyzed the flowering phenology and pollen characteristics of6clone Carya illinoensis, including the flowering phenology, pollen morphology, pollen viability, pollen storage, and cross pollination. The results are as follow:The staminate and pistillate of different clone Carya illinoensis has different flowering phenology. The difference in flowering phase of the6clone pistillate flowers range from2to10days, and1to9days among the staminate flowers.Differences also exist among the same clone of different years, while the flowering sequences of different years are relatively stable. The flowering time of staminate and pistillate in different places is significantly different. In regard to the pistillate of No.104,the first flowering date of Jiande is27th April, the earliest among the three places. While Anji is the latest,3May. For the staminate of No.104, the initial dehiscence time of Jiande is10th may, Anji15th may, Yuhang12th may. The dehiscence duration lasts for8to10days, while the full dehiscence duration lasts for5to6days. Different canopy and direction of the same clone staminate and pistillate has different flowering phenology. For pistillate, there are slight differences among the4directions, as east and south are1day early than west and north. For staminate, the differences are not obvious among the4direction. However, the dehiscence time of high and low two layers of crown exist differences, and the high layer is1day early than the low layer.There are significant differences on the pistillate flowering number and staminate ordinal of the6clone Carya illinoensis(P<0.05).According to the observation of the6clone pollen with SEM, the6clone pollens are medium size, oblate shape (No.104is nearly round.). All pollens have three apertures which are evenly disposed on the equatorial plane. The equatorial plane of this6clone pollen are oval in shape, while the polar plane of clone No.5,21,27and104are nearly round, No.28and35nearly triangular. There are granular decorate on the surface of the pollen with granular risings equally distributed. Granular of clone No.21and27are distributed densely, and No.5and28are distributed sparsely, while No.35and104are distributed between the former two kinds. According to the cluster analysis of the6clone Carya illinoenis pollen, the9indices of each cluster are extremely close, such as clone No.35and104,21and27,5and28, which provides palynology explanation on the phylogenetic relationship.With one-way ANOVA analysis, it is found that pollen viability of the same clone under different treatment present significant differences (p<0.05).The sequences of pollen viability are as follow:desiccant treatment≈drought treatment>dry in constant temperature30℃>dry in sunshine. Pollen viability of the same clone in different dehiscence periods reaches significant differences (p<0.05). The pollen viability of Clone No.5,27,35is as follow:full dehiscence is higher than initial dehiscence, and final dehiscence is lower than initial dehiscence. Pollen viability of the same clone under24h,48h,72h drought treatment all reaches significant differences (p<0.05). Pollen viability of clone No.5,27,35presents that, collected after24h>48h>72h.The4kinds of storage have obvious effects on the pollen viability, such as storage in room temperature,0to5℃,-20℃, and-79℃. Under the room temperature situation, pollen viability of3clones (No.5,27,35) is low after16days storage. After30days storage, pollen of the3clones is out of viability. Under0-5℃, pollen viability of3clones is declined to20%after90days storage, while No.35is the most storage resistance, and the viability is still up to10%. Under-79℃and-20℃, pollen viability is much more storage resistance, as the viability of3clones after270days storage is22%to28%under-79℃, and13%to22%under-20℃.As for the cross pollination on the same female parent, there are differences with different male parents. Clone No.21and28have the highest compatibility with No.35among the3pollination clones, and clone No.104with No.5.As for the cross pollination on the same male parent, No.5,No.27and No.35have the highest compatibility all with No.21among the3female parent.更多还原