关键词: 弱光胁迫, 产量, 综合性状, 相关性, 聚类分析, 微生物群落, 功能多样性, 季节变化, Biolog, 冗余分析, 环境因子, 刺参池塘

Abstract: A field experiment was conducted to study the morphological, physiological, and yield traits of 24 maize cultivars under 50% shading. Comparing with t
he control, 50% shading decreased the plant height, stem diameter, leaf net photosynthetic rate (P_n), specific leaf weight (SLW), aboveground dry matter accumulation, ear length and diameter, axis diameter, and kernels per row. The interval from anthesis to silking (ASI) was prolonged, and the grain yield was decreased significantly. The percent changes of ASI,P_n,SLW, and kernels per row were significantly correlated with aboveground dry matter accumulation and grain yield, being able to be used as the indices to evaluate the maize shade-tolerance in field. Cluster analysis using comprehensive shade-tolerance traits as evaluation parameters indicated that 14 maize cultivars including Zhengdan 958, Xundan 20, and Denghai 602, etc. were of shade-tolerance type, and 10 cultivars (Anyu 12 and Yuyu 22, etc.) were of shade-sensitive type. It was suggested that adopting the morphological, physiological and yield traits as the indices to evaluate the shade-tolerance of maize would be more objective, simple and practical.

Key words: low-light stress, yield, comprehensive traits, correlation, cluster analysis, microbial communities, functional diversity, seasonal variation, Biolog, redundancy analysis (RDA), environmental factors, sea cucumber cultural ponds.