温度对不同秋眠型紫花苜蓿光敏色素和内源激素的影响

摘要

Three fall dormancy types and five different temperatures were designed to study the regulation of phytochrome (A and B) and endogenous hormones on the fall dormancy of Medicago sativa.Major results were that PHYA content in the leaves of Norseman (FD 1) was lower than that in Dupuils (FD 5)and CUF101 (FD 9),and PHYA contents in 12～24℃ were higher than in 6℃ and 30℃.PHYB content in the leaves of Norseman (FD 1) decreased gradually with the temperature increasing.The endogenous hormone GA3 and IAA contents of leaves in 12～24℃ were higher than in 6～30℃,but ABA was opposite.These results showed that ABA content was higher than other endogenous hormones in Medicago sativa.Temperature affected the fall dormancy of Medicago sativa,phytochrome (A and B) and endogenous hormones played a major role in fall dormancy.%为探讨温度对不同秋眠型苜蓿(Medicago sativa)光敏色素表达量和内源激素含量的影响,以3个不同秋眠型紫花苜蓿品种为材料,设计5个不同的温度梯度(6,12,18,24和30℃)处理35 d,测定叶片中光敏色素和植物激素的含量,分析温度与苜蓿秋眠的关系.结果表明:与半秋眠、非秋眠型苜蓿相比,秋眠型苜蓿Norseman(FD1)叶片中的P HYA表达量低,且有随着温度升高而升高的趋势；非秋眠品种CUF101(FD9)在低温(6℃)和较高温度(24和30℃)时PHYA表达量较低,12和18℃时含量较高;Dupuils (FD5)在各个温度条件下变化不大.温度对苜蓿品种Dupuils(FD5)和CUF101(FD9)中PHYB含量无规律性影响,但Norseman(FD1)从低温到高温的PHYB表达量呈明显的递减趋势,低温有利于PHYB基因的表达.在适合于苜蓿生长的温度条件下,叶片中GA3,ZR和IAA含量较高,低温(6℃)和高温(30℃)时上述生长激素含量下降.因此,苜蓿的秋眠性受温度影响,PHYA和PHYB对苜蓿的秋眠有调控作用,低温和高温不利于生长激素的合成.