Response of leaf morphology,population structure and yield to planting density in rice

To analyse the response of leaf morphology,population structure and yield to planting density in rice,four high-yield rice lines JW10,JW103,JW113 and JW34 were used to study the effects of different plant density(low density,medium density,high density) on rice leaf morphology,leaf area index,leaf area distribution,photosynthetic rate,chlorophyll fluorescent parameters,dry matter production and yield.The results showed that the leaf length,leaf width and drooping degree of rice varied with planting densities.The upper canopy area in medium-density population was higher than those in the low-density and high-density treatments.The photosynthetic rate and chlorophyll fluorescent parameter(Fv/Fm) of leaf in medium-density population at full heading stage fell to the value between those in the low density and high density treatments.After full heading stage,the photosynthetic capacity in medium-density population was superior to the others.All these indicate that under the existing conditions and technology,the traditional density of about 30 million hills per hectare is an appropriate planting density.