3种结缕草及其^(60)Co-γ辐射诱变新品系抗旱性比较

A comparison of drought resistance of three zoysiagrasses and their new strains induced by ^(60)Co-γ radiation

【目的】探究3种结缕草Zoysia japonica及其60Co-γ辐射诱变选育的6种新品系间抗旱性的差异.【方法】以兰引Ⅲ号(LY)、ZS-1(ZS)和ZS-SJZ(ZSS)3种结缕草及其6种新品系为材料,在盆栽条件下进行干旱胁迫处理,在干旱胁迫处理后第3、9、15天测定叶片相对含水量、相对电导率、脯氨酸含量、可溶性总糖含量,同时观测草坪草盖度和颜色变化;干旱胁迫处理后复水,观测草坪草盖度和颜色变化.【结果和结论】随着干旱胁迫的加剧,结缕草叶片相对含水量不断下降,脯氨酸含量、可溶性总糖含量和相对电导率呈上升趋势,草坪盖度和颜色评分降低.通过隶属函数标准差系数赋予权重法对9份材料的抗旱性进行综合评价,抗旱性从强到弱依次为ZSS-5>ZS-3>LY>LY-2>ZS>ZS-4>LY-1>ZSS-6>ZSS,新品系ZSS-5、ZSS-6、ZS-3抗旱性优于其亲本,说明结缕草可以通过辐射育种选育抗旱品种.

【Objective】To evaluate the differences of drought resistance of three zoysiagarasses, Zoysia japonica, and their new strains induced by ^60Co-γ radiation. 【Method】Three zoysiagrasses including Lanyin No.Ⅲ （LY）, ZS-1 （ZS） and ZS-SJZ （ZSS）, and their six new strains were cultivated in pots under the drought stress condition. The relative water content, relative electrical conductivity, proline content and total soluble sugar content of leaves were measured on the 3rd, 9th and 15th day after the drought stress treatment. The turfgrass coverage and color were observed and evaluated during the drought stress.【Result and conclusion】With the increase of drought stress, the relative water content of leaves decreased gradually and turfgrass coverage and color scores also reduced, whereas the proline content, total soluble sugar content and relative electrical conductivity of leaves had an upward trend. Through the comprehensive evaluation of drought resistance with subordinate function weights coefficient of standard deviation,the drought resistance ability ranks of the tested materials were as follows： ZSS-5〉ZS-3〉LY〉LY-2〉ZS〉ZS-4〉LY-1〉ZSS-6〉ZSS, which demonstrated that the drought resistance abilities of new strains ZSS-5, ZSS-6 and ZS-3 were stronger than those of their parents. The radiation breeding is an effective way to breed new drought-resistant zoysiagrass varieties.