酸胁迫对不同基因型玉米生长和养分吸收的影响

采用盆栽试验研究了4个不同耐酸特性的玉米自交系在几个关键生育期的氮、磷、钾营养特性和生长状况。结果表明,耐酸自交系在苗期、拔节期和开花期对氮、磷、钾的吸收和累积均高于酸敏感自交系;不同生育期耐酸自交系的营养利用率和再分配特征存在差异,苗期表现为氮的利用率较高,开花期表现为磷、钾营养的再分配能力强。不同耐酸材料对酸胁迫土壤反应不同,耐酸自交系在不同生育阶段始终能较好生长,尤其是Z01,即使在pH4.6的酸性土壤上干物质累积几乎不受酸胁迫影响;中等耐酸自交系则受酸的危害,且随着发育进程而加剧,而酸敏感自交系表现出与中等耐酸材料相同的趋势,但各生育阶段受到的危害更大。

Effect of acid-stress on growth and nutrient absorption of different maize genotypes

Growth and n were studied at stages of utrient characteristics of N, P and K in seedling, shooting and flowering in a pot istics of N, P and K of maize genotypes shooting and flowering, the efficiency of different maize inbred lines with tolerance to acid-stress experiment. The results showed that nutrient charactervaried under acid-stress at different growing time. In the periods of seedling uptake and accumulation of N, P and K of acid-tolerance genotypes were higher than those in acid-sensitive genotype. The mechanism of the tolerance to acid-stress represents not only higher uptake efficiency but also stronger ability of utilization and the reallocation and reutilization. The nutrient mechanism of tolerance to acid-stress may differ with growth stages. We found that N utilization efficiency was one of contributors to acid tolerance at seedling stages. To flowering stage, stronger ability of the reallocation and reutilization of P and K contributed to adaptation to acid-stress. The investigation of relative dry weight also suggested that there were remarkable differences in responses to acid stress among various maize genotypes. With the development of crop growth, the acid-stress symptom of medium acid-sensitive genotype was aggravated, but it had little effect on the acid-resistant genotypes even in acid soil of pH 4.6 for acid-tolerance genotype Z01. The type, compared characteristics and the dry matter weight of the acid-sensitive genoto medium acid-sensitive genotype, were more significantly influenced by acid stress.