我国北方草地6种乡土植物抗逆机理与应用

Stress tolerance mechanisms of 6 native plant species growing in China's northern grassland and their utilization

研究和利用我国丰富的乡土草资源,使之更好地服务于社会发展与经济建设,是一项长期性的工作.本文概述霸王(Zygophyllum xanthoxylum)、白沙蒿(Artemisia sphaerocephala)、微孔草(Microula sikkimensis)、醉马草(Achnatherum inebrians)、无芒隐子草(Cleistogenes songorica)和羊草(Leymus chinensis)等我国6种乡土植物抗逆机制的研究及其应用.主要结果和发现如下:在明确霸王抗旱生理机制的基础上,克隆其抗旱基因,实现了在紫花苜蓿(Medicago sativa)和百脉根(Lotus corniculatus)遗传改良中的应用;白沙蒿和微孔草富含多不饱和脂肪酸,以种子含量最高;通过醉马草-禾草内生真菌共生体多样性的研究,发现醉马草共生体所产生的生物碱是增强其抗生物和非生物因素胁迫以及引致家畜中毒的主要原因;通过系统研究无芒隐子草生物学、生理学及分子生物学特性,成功地对其进行驯化选育、选育新品系,并建立了建植与种子生产技术;初步明确了羊草种子的休眠机制,提出了破除休眠的有效方法.

It is a long term work to assemble the knowledge needed to utilize the rich native plant resources to assist social and economic development in China. The progress of the research results and their application of mechanisms underlying the stress-tolerance in native plants including Zygophyllum xanthoxylum, Artemisia sphaerocephala, Microula sikkimensis, Achnatherum inebrians, Cleistogenes songorica and Leymus chinensis were reviewed in this paper. The main results and findings are as follows： based on discovering the physiological mechanism of drought tolerance of Z. xanthoxylum, the key genes involved in drought tolerance were cloned and applied into the genetic improvement of important legume forage lucerne（Medicago sativa） and lotus（Lotus corniculatus）; the desert shrub A. sphaerocephala and alpine species M. sikkimensis contain high contents of polyunsaturated fatty acids, the highest contents being found in the seeds; the diversity of drunken horse grass fungal endophyte symbiont was investigated on a national scale. The alkaloids produced by the symbiont are the main reason for both increased plant stress tolerance and the toxicity symptoms observed after intake by grazing animals; the biological, physiological and molecular genetic characteristics of C. songorica were studied. As a result, the species is expected to be domesticated successfully. Technical information on procedures for pasture establishment and seed production of this species has been developed; the seed dormancy mechanisms of L. chinensis were explored, and techniques to effectively break dormancy were developed.