苜蓿-根瘤菌复合盐高效抗性共生体系构建

Establishment of highly efficient and salt tolerance alfalfa rhizobia symbiotia

为构建具有盐渍土环境竞争力与遗传稳定性的苜蓿(Medicago)-根瘤菌高效共生体系,以12个苜蓿品种为材料,进行了复合盐种子萌发、种子内生根瘤菌抗盐碱筛选及接种试验。结果表明,不同品种间种子复合盐抗性差异较大,成活率以中苜1号最高,甘农7号、新疆大叶次之,但三者间无显著差异;种子内生根瘤菌复合盐抗性以甘农1号最强,菌株数目最丰,为2.58×106,中苜1号次之,为2.49×106,根瘤菌固氮酶活性以中苜1号最高;以新疆大叶种子接种中苜1号根瘤菌匹配度为最佳,共生体系地上生物量、茎叶粗蛋白含量以及固氮酶活性均为最高。

In order to establish the high efficient alfalfa-rhizobia symbiotia with competitive ability and genetic stability in saline soil,germination,rhizobia salt tolerance and inoculation experiments were conducted using 12 alfalfa cultivars.The results indicated that the seed salt tolerance varied greatly among cultivars.The highest of seed salt tolerant survival percent was Zhongmu No.1and second highest of that was Xinjiangdaye and Gannong No.7although there was no significant difference between these three research group.The highest of rhizobia salt tolerant was Ganonng.1with the rich strains number of 2.49×10^6.Zhongmu.1.of Xinjiangdaye symbiotic with rhizobia isolated from zhongmu.1had highest salt resistance and nitrogenase activity of rhizobia and the highest efficiency with the highest aboveground biomass,stem and leaf crude protein content and nitrogenase activity.