不同基因型橡胶树花药体胚发生能力的差异分析

目的 探明不同基因型橡胶树的体胚发生能力差异，为优化橡胶树不同品种体胚发生体系提供理论基础。 方法 以国家橡胶树种质资源圃保存的32个橡胶树主栽品种及其亲本为材料，通过系谱分析明确品种间的遗传关系，并以花药作为外植体诱导愈伤组织并进一步诱导体胚发生，结合体胚诱导率和遗传关系分析不同基因型体胚发生能力的差异。 结果 对32个橡胶树品种进行系谱分析表明：PR107、GT1、PB86、Tjirl、海垦1、天任31-45、合口3-11这7个品种为初生代无性系，其余25个品种中的23个与以上7个初生代无性系中的1 ～ 3个存在亲缘关系，表明我国橡胶树主栽品种亲本来源狭窄。结合系谱和体胚发生结果分析表明：橡胶树品种的体胚发生能力与亲本来源密切相关，亲本体胚发生能力决定其子代品种体胚发生能力。父母本均为难诱导体胚发生品种时，其杂交后代多数难诱导体胚发生；父母本中含1个易诱导体胚发生品种，即使另1个亲本为难诱导体胚发生品种时，其杂交后代多数体胚发生效率高，但这些后代间体胚发生频率差异显著，且存在超亲现象，推测橡胶树体胚发生是由多基因参与控制的。GT1、天任31-45、93-114和RRIM513等为难诱导体胚发生品种，以其为亲本来源的杂交后代多数难以诱导体胚发生（如云研77-2、云研77-4、云研73-46、保亭1-285、湛试32713、热研217），而PB86、RRIM600、热研88-13和海垦1等为易于诱导体胚发生品种，以其为亲本之一的杂交后代多数体胚发生效率高（如大丰95、海垦2、热研917、热研73397、热研879、热研918、徐育3、徐育141-2）。 结论 本研究发现，橡胶树体胚发生能力存在明显的基因型差异，且这种差异可遗传。依据体胚诱导率和遗传关系，本文将橡胶树亲本的体胚形成率同子代的诱导率结合进行分析并分组，为利用基因型分组优化橡胶树栽培品种的体胚发生体系提供了依据。

Differential Analysis of Anther Embryogenesis between Different Genotypes of Hevea brasiliensis

Objective Clarifying the effect of genotype on rubber tree somatic embryogenesis and combining with pedigree analysis to classify and group will provide a theoretical basis for accurately optimizing the somatic embryogenesis system of rubber trees. Method The genetic relationship between the 32 main rubber tree cultivars and their parents preserved in China National Rubber Tree Germplasm Repository was clarified through pedigree analysis. The two mediums with high somatic embryo induction rate in multiple cultivars in the previous experiment were used to induce callus and further induce somatic embryogenesis with anthers as explants. Finally, the induction rate of somatic embryos based on genetic relationship was analyzed. Result The pedigree analysis of 32 rubber tree cultivars showed that 7 cultivars were primary clones including PR107, GT1, PB86, Tjirl, Haiken1, Tianren31-45, and Hekou3-11. Twenty-three of the remaining 25 cultivars are genetically related to 1-3 of the above 7 cultivars. It is clear that the source of parents of rubber tree cultivars in China is narrow. Combining pedigree and somatic embryogenesis analysis showed that the somatic embryogenesis ability of rubber tree cultivars is closely related to the parental source, and the parental somatic embryogenesis ability determines the somatic embryogenesis ability of its offspring cultivars. When both parents are recalcitrant to somatic embryogenesis, most of their hybrid progeny are recalcitrant. When one of the parents has high somatic embryogenesis efficiency, even if the other parent is recalcitrant, most of its hybrid offspring have high somatic embryogenesis efficiency. However, the frequency of somatic embryogenesis varies significantly among these offspring, and there is a phenomenon of super-parental, which indicates that the rubber tree somatic embryogenesis is controlled by the participation of multiple genes. GT1, Tianren31-45, 93-114, RRIM513, and other parent-derived cultivars have low somatic embryo induction rate (e.g., Yunyan77-2, Yunyan77-4, Yunyan73-46, Baoting1-285, Zhanshi32713, and Reyan217), and PB86, RRIM600, Reyan88-13, and, Haiken1 and other parent-derived cultivars have high somatic embryo induction rate (e.g., Dafeng95, Haiken2, Reyan917, Reyan73397, Reyan879, Reyan918, Xuyu3, and Xuyu141-2). Conclusion There are obvious genotypic differences in rubber tree somatic embryogenesis, and this difference can be heritable. According to the somatic embryo induction efficiency and genetic relationship, analyzing and grouping 32 main rubber tree cultivars and their parents provide a way to optimize the somatic embryogenesis of rubber tree cultivars by genotype grouping.