四川盆地及盆周山区玉米地方种质耐低磷胁迫研究

Study on the Response to Low Phosphorus Stress in Maize Landraces in Sichuan Basin and the Mountain Areas Around Sichuan Basin

以来自四川盆地及盆周山区的22个玉米地方种质为材料,在低磷胁迫下对苗期缺磷症状,成株期株高、穗行数、百粒重、行粒数以及穗粒重等性状表现进行了研究。结果表明,低磷胁迫对玉米的主要农艺、经济性状均有不同程度的影响,其中对苗期缺磷症状及成株期穗粒重的影响最大,且不同玉米地方种质在苗期和成株期对低磷胁迫的反应不同,以苗期缺磷症状和成株期穗粒重的耐低磷胁迫系数的平均值作为耐低磷综合指数,能较好地反映玉米地方种质的耐低磷胁迫能力。将耐低磷综合指数按最短距离法进行聚类,可将22个玉米地方种质划分为三类。其中,第一类材料包括：汉源红包谷、汉源白包谷、汶川二白、江北大板牙,占鉴定总数的18.2%,它们的耐低磷综合指数在0.81以上,属于对低磷胁迫不敏感基因型;第二类材料包括南充秋子等4个玉米地方种质,占鉴定总数的18.2%,它们的耐低磷综合指数在0.73-0.77之间,属于对低磷胁迫反应中间型;第三类材料包括小金金皇后等14个地方种质,占鉴定总数的63.6%,它们的耐低磷综合指数在0.73以下,属于对低磷胁迫敏感基因型。

Under the low phosphorus conditions, 22 maize landraces which from Sichuan Basin and the Mountain Areas Around Sichuan Basin have been studied on the lacking phosphorus for maize seedling stage, plant height, rows per ear, 100- kernel weight, kernels per row and kernel yield per ear. The results showed that there were different responses to low-P stress in different characters ,especially on lacking phosphorus for maize seedling stage and kernel yield per ear. Different landraces respond differently to low-P stress. The index based on relative lacking phosphorus for maize seedling stage and kernel yield per ear was suggested as a screening standard to identify low-P tolerance of maize landraces. According to above index, 22 maize landraces had been divided into 3 groups. The first one included four maize landraces, there index were before 0.81, were typical genotypes with tolerance to low-phosphorus ;The second included 4 maize landraces,there index were between 0.73- 0.77 ,were common genotypes with tolerance to low-phosphorus; While 14 maize landraces were sensitive to low-phosphorus stress, there index were below 0.73.