40份竹节草种质资源抗旱性初步评价

以40份竹节草（Chrysopogon aciculatus）种质为材料,采用0（CK）、15%（T₁）和20%（T₂）3种浓度的PEG-6000溶液模拟干旱胁迫,对其进行抗旱性初步评价。结果表明,随着PEG浓度增加,干旱胁迫下不同竹节草种质枯黄率和萎蔫系数呈增加趋势,不同处理间差异显著;相对于T₁处理,T₂处理下枯黄率和萎蔫系数增幅更大,变化更明显;T₁处理可促进根系生长,而T₂处理有抑制作用,种质间呈现显著性差异。相关性分析表明,枯黄率、萎蔫系数、相对总根长、相对根体积、相对根表面积之间均呈现极显著相关,相对根直径与萎蔫系数、相对根长之间显著相关,与其他形态指标之间无显著相关性,运用隶属函数对竹节草抗旱性进行综合分析,分为抗旱种质（CA04、CA26、CA23、CA58）和敏旱种质（CA03、CA59、CA78、CA40）。本研究结果可为今后开展竹节草抗性育种提供参考。

Preliminary Evaluation of Drought-resistance among 40 Chrysopogon aciculatus Germplasm Resources

In this study, 40 Chrysopogon aciculatus germplasms were used as the materials to simulate drought stress in PEG-6000 solutions at three concentrations of 0 (CK), 15% (T₁) and 20% (T₂), and to evaluate the drought resistance. With the increase of PEG concentration, the withering rate and wilting coefficient under drought stress showed an increasing trend and there had significant difference between different treatments. Compared with T₁ treatment, the withering rate and wilting coefficient increased significantly and changed more obviously under T₂ treatment. T₁ treatment promoted root growth, while T₂ treatment inhibited, and there were significant differences among germplasms. Correlation analysis showed that there was a significant correlation among withering rate, wilting coefficient, relative total root length, and relative root volume and relative root surface area were significantly positively correlated, while the relative root diameter had a significant correlation with wilting coefficient and relative root length, and there was basically no correlation between relative root diameter and other morphological treat. The drought resistance of C. aciculatus was comprehensively analyzed by membership function, which was divided into drought-resistant germplasm (CA04, CA26, CA23, CA58), and drought-sensitive germplasm (CA03, CA59, CA78, CA40). The study would provide a reference for developing resistance breeding of C. aciculatus in future.