棉花苗期钾营养效率的基因型分类及钾营养特性差异分析

采用营养钵砂培法,将相对生物量及与之存在显著或极显著相关的6个养分相关辅助指标作为棉花苗期钾营养效率差异评价指标。并基于上述指标,利用SAS软件对38个品种(系)的钾营养效率进行聚类分析,最后综合归纳,将其划分为4种钾效率类型,分别为耐低钾型、较耐低钾型、中间型及低钾敏感型,各包括3个、4个、26个及5个品种,总体呈现出中间多两头少的正态型分布,表明这些指标能较好地反映各品种间钾营养效率的差异。此外,对两极端钾效率类型间的营养特性进行了差异比较与分析,结果表明耐低钾基因型的相对生物量高,具有在低钾下对钾素吸收积累能力强和利用指数高的特点,且二者缺一不可;而低钾敏感型恰恰相反,表现为低钾下相对生物量低,对钾吸收积累能力差、利用指数低的特点。

Classification and Analysis of Potassium Nutrition Efficiency and Characteristics in Different Cotton Genotypes at Seedling Stage

In this experiment, using a feeding block sand culture method, we examined relative biomass and six other nutrient-related supplementary indexes that had significant or extremely significant correlation with relative biomass to evaluate differences in potassium nutrition efficiency in cotton at the seedling stage. Using the SAS8.0 software, cluster analysis based on the above indexes was performed to classify 38 cotton varieties (strains) of different potassium nutrition efficiency. The cotton varieties were divided into four types: K tolerant (3), K slightly resistant (4), K intermediate (26) and K sensitive (5) genotypes, which generally presented a normal distribution, indicating that these indicators can reflect differences in potassium nutrition efficiency between different cotton varieties. Additionally, we carried out a comparative analysis of the potassium nutrition characteristics between two extreme potassium efficiency types. We found that the biomass of low potassium tolerant genotypes was less affected by low potassium stress, which had the traits of stronger K absorption ability and a higher K utilization index at low K levels, both of which are indispensable. Conversely, low potassium sensitive genotypes had less K absorption ability, a lower K utilization index and low relative biomass at low K levels.