Study On Biocompensation Of Different Genotype Maize Under Successive Drought And Rewatering In Seedling Stage

Pot experiment has been conducted in a randomized complete block design with control group(with sufficient water supply)and treatment group(with 3 successive cycles of drought and re-watering)under rain-proof shelter.Two inbred line parents and their hybrid generation has been used as experimental materials.The objective of this study was to determine the morphological and physiological responses of drought and re-watering and their biocompensation effect in maize.The results showed that:1.In terms of growth and development,the plant height and leaf area of F1 generation only increased significantly in the final stage of treatment,and plant height growth of F1 generation was delayed under successive drought and rewatering.The plant height of F and M inbred lines increased significantly only after rewatering under the first drought stress.2.Successive drought and rewatering significantly increased the accumulation of aboveground biomass of F1 plants,while it was decreased in F and M compared with control plant.3?Successive drought and rewatering significantly increased root biomass of F1,F and M,while the root biomass was increased more than M and F,and it was showed earlier in F1 than in M and F.4.Successive drought and rewatering significantly promoted osmotic adjustment and antioxidant adjustment of F1 hybrid.The anti-oxidative regulation of leaf cells of F and M was significantly reduced under successive drought and re-watering.5.The aboveground growth recovery ability of F1 generation was significantly improved,and the underground growth of M and F were significantly promoted.The root-shoot ratio of F1 hybrid decreased,the specific gravity of canopy growth in total biomass increased,and the root-shoot ratio of F and M increased after successive drought and re-watering.6.The reason for the improvement of growth recovery ability and overcompensation effect in F1 generation is the high water and pigment holding capacity of leaves under stress,and the rapid recovery of photosynthetic and fluorescence properties after rewatering,so thatthe dry matter accumulation is concentrated and distributed in the aboveground part.This is also because of the genetic potential of F1 hybrid was stimulated after continuous drought and rewatering.