Identification of Maize Genotypes with High Tolerance or Sensitivity to Phosphorus Deficiency

• Published in: Journal of plant nutrition 2011-06, Vol.34 (9), p.1290-1302
• Main Authors: Gong, YangMin, Guo, ZaiHua, He, LiYuan, Li, JianSheng
• Format: Article
• Language: English
• Subjects: absorption; absorption efficiency; Agronomy. Soil science and plant productions; Biological and medical sciences; corn; Economic plant physiology; Efficiency; Fundamental and applied biological sciences. Psychology; genotype; hydroponics; maize (Zea mays L.); Metabolism; Metabolism. Physicochemical requirements; nutrient solution culture; Nutrition. Photosynthesis. Respiration. Metabolism; phosphorus; phosphorus deficiency; Plant physiology and development; root shoot ratio; screening; seedlings; shoots; soil; soil culture; Soil science; use efficiency
• ISSN: 0190-4167; 1532-4087; 1532-4087
• DOI: 10.1080/01904167.2011.580816

Soil culture containing phosphorus (P) supply of different levels may be used to screen maize genotypes for resistance to P deficiency. Relative dry weight and P-deficiency symptom level were proven to be fast and efficient indicators for screening of the P-deficiency tolerant genotypes at the stage of seedling. Two maize genotypes, HZS15 and HZS03 were identified as highly sensitive genotypes under P deficiency, simultaneously, HZT32 and HZT33 had extremely high tolerance to P deficiency. The yield experiment confirmed the reliability of this selecting strategy at the stage of seedling. The yield analysis revealed that HZT32 and HZT33 had higher average yield of each plant and thousand-grain weight than those of HZS15 and HZS03. Successively, responses of four genotypes to P deficiency were investigated with simplified hydroponic culture system. Elongated taproot and increased ratio of root to shoot were observed in all four genotypes. However, two P-deficiency-tolerant genotypes had higher ratio of root to shoot than those in P-deficiency-sensitive genotypes. Phosphorus efficiency analysis revealed that under P deficiency HZT33 had higher P absorption efficiency than those of other three genotypes, and two P-deficiency-tolerant genotypes had higher P use efficiency than that of two P-deficiency-sensitive genotypes. These results indicated that the tolerance of HZT32 and HZT33 to P deficiency might primarily be ascribed to high P use efficiency. Moreover, high P absorption efficiency contributed partially to the tolerance of HZT33 under P deficiency. Further research is needed to elucidate the complex correlation between other physiological traits and P efficiency.