Root zone temperature influences nutrient accumulation and use in maize

摘要

Root-zone temperature (RZT) changes with season, geographical location and global warming. Nutrient accumulation and use behaviour of two maize (Zea mays L.) genotypes were evaluated under low (22.4 ± 5°C) and high (28.8 ± 5°C) root-zone temperatures. In greenhouse study, hybrid maize (FHY-396) and indigenous variety (EV-7004) were sown in calcareous loam soil filled in pots. Shoot and root dry matter yield of both the genotypes was significantly (p0.05) increased at the higher RZT. On an average, shoot dry matter at the higher RZT was 38% more for hybrid and 52% for indigenous variety (EV-7004). Concentration and uptake of estimated nutrients (P, K, Cu and Zn) was significantly (p0.05) influenced by RZT. At the higher RZT, shoot concentrations of both Cu and Zn were increased by about 30%. There was 1.5-fold increase in P, 1.4-fold increase in K, 1.9-fold increase in Cu and 1.8-fold increase in Zn uptake at the higher RZT. Nutrient uptake (uptake g. 1root) and use efficiencies (shoot utilization efficiency and usage index) were significantly (p0.05) increased at the higher RZT. Genotypes also differed significantly (p0.05) for P and Zn utilization efficiencies. Conclusively, RZT had a pronounced role in nutrient uptake from soil and their use by plants and hence on plant growth.