浒苔与缘管浒苔人工杂交遗传育种技术

Artificial hybridization and cross-breeding of Ulva

报道浒苔与缘管浒苔的人工种间杂交技术。利用浒苔属藻类生殖细胞配子与孢子的趋光性差异性,结合其同型世代交替生活史特性,从绿藻群落中分别筛选出浒苔与缘管浒苔的雌雄配子体母本藻体。通过对浒苔雌配子体和缘管浒苔雄配子体进行生殖细胞诱导试验,分别同时获得纯化的雌雄配子液,经均匀混合与显微观察,发现浒苔雌配子和缘管浒苔雄配子快速向彼此游动,接合形成具有负趋光性的合子;接合过程中,雌雄配子鞭毛逐渐消失,运动力逐渐下降,由梭形逐渐转变成为圆形。将纯化合子进行室内培养,获得杂交后代藻体,经凝胶电泳及分子生物学检测,发现杂交种在5SrDNA间隔区序列上同时具有浒苔和缘管浒苔的特异性序列,确认两种浒苔属绿藻成功实现种间杂交。此项技术在国内尚未报道,可为未来开发多种优质性状浒苔品系提供技术示范,为开展浒苔规模化养殖和获得稳定高产浒苔资源提供科学支撑。

The technique of interspecific hybridization between Ulva prolifera and Ulva linza was reported.Based on the phototactic response of zoids and the characteristics of life cycle,female gametophyte of U.prolifera and male gametophyte of U.linza was selected from the Ulva population.Mature thalli were induced to release gametes in a Petri dish under a unilateral light source.Gametes were purified at least twice according to their respective phototaxis.By homogeneous mixing and microscopic observation,we can find that female and male gametes swam rapidly to each other and joined to form zygotes.During the process of conjugation,the flagella of female and male gametes gradually disappeared,the motility decreased,and the shuttle-shaped gametes changed into round zygotes.After twice purification,the zygote can grow into the offspring of Ulva.The progeny of Ulva was examined by gel electrophoresis and molecular biology.Result showed that the hybrids had specific sequences of U.prolifera and U.linza on 5S rDNA spacer sequence.The successful hybridization of U.prolifera and U.linza was confirmed and the artificial hybridization technology of Ulva was established.This technology has not yet been reported in China before,and it can provide a technical demonstration for the future development of a variety of high-quality traits of Ulva strains.It can also provide scientific support for carrying out large-scale facility culture and obtaining stable and high-yield biomass of Ulva.