外源ABA对不同秋眠型苜蓿品种植物激素含量的影响

选择第3生长年的苜蓿90株,采用2因素3水平试验设计方法,随机分为9个处理组,每组5个重复,每个重复1盆,每盆2株,分别用0,20和80 mg/L外源ABA处理3个不同秋眠级别的苜蓿品种CUF101、CW502和Ver-nal,试验期35 d。通过酶联免疫吸附测定法,观测外源ABA处理的不同秋眠级别苜蓿激素含量变化,并探讨激素调控对苜蓿生长和秋眠的影响。结果表明,1)无论是非秋眠型苜蓿CUF101,半秋眠型苜蓿CW502,还是秋眠型苜蓿Vernal,其顶芽和第1展开叶中ABA含量均随外源ABA喷施浓度水平的提高而增加,IAA、GA3含量则表现出与ABA相反的递减趋势;2)在同一环境因素影响下随着苜蓿秋眠性增强,内源ABA合成量呈递增趋势,而IAA、GA3合成量呈递减趋势,秋眠型苜蓿更易受外源ABA影响促进内源ABA的累积;3)短日照适温环境中随着苜蓿秋眠级别的升高和ABA/IAA、ABA/GA3、ABA/ZR值的降低,株高增长变化呈递增趋势。本试验认为,虽然短日照适温环境只能促使苜蓿轻度休眠,但内源ABA累积量随秋眠级别降低而增加,也为进一步探讨苜蓿秋眠调控机理、人为调控苜蓿休眠以及提高苜蓿的抗寒力提供了理论依据。

Effects of exogenous ABA on hormone content in different varieties of fall dormancy Medicago sativa varieties

An experiment was conducted using 90 M.sativa plants in the age of three years to study the effects of variety and exogenous ABA on endogenous hormone content and fall dormancy.M.sativa plants were randomly divided into nine treatments according to two factors and three levels of each factor.Each treatment had five replicates of 2 plants each.Three varieties CUF101,CW502 and Vernal were treated with 0,20,80 mg/L exogenous ABA concentration during a 35 day period.M.sativa endogenous hormone content was measured by an enzyme-linked immunosorbent assay(ELISA).Three major results were obtained: 1)In the buds and the top one unfolding leaves of shoots of each variety,ABA content was increased as exogenous ABA spraying concentration was increased,but IAA and GA_3 content were decreasesd successively.2)The endogenous ABA content in M.sativa decreased as M.sativa fall dormancy class increased and increased for endogenous IAA,GA_3 content.Besides,fall dormant M.sativa was easier to accumulate endogenous ABA as an effect of exogenous ABA.3)In conditions of short day and moderate temperature,plant height increased with the dormancy were weakened in M.sativa,but ABA/IAA,ABA/GA_3,ABA/ZR had reverse tendency.The study also showed that,although M.sativa can only be lightly dormant in short day and moderate temperature,the accumulation of endogenous ABA increased as fall dormancy class decrease.This offered effective help for the further discussion of the fall dormancy mechanism.At the same time,the results that exogenous ABA influenced fall dormancy levels can help us in further research on M.sativa dormancy and in effects to improve M.sativa cold resistance.