Effects of fertilization mode and reduced nitrogen fertilizer on lodging resistance of rice in cold region
In order to clarify the effects of fertilization methods and nitrogen reduction on rice yield and lodging resistance in cold region,'Kenjing No.8'was used as the material to compare the differences of yield,plant height,internode length,diameter,fresh weight,stem wall thickness and lodging resistance of rice under different fertilization methods and nitrogen reduction.The results showed that the yield,length of third internode and height of center of gravity of lateral fertilization were significantly or respectively higher than those of full fertilization by 7.49%,7.02%and 2.54%,respectively.The diameter of first internode,stem wall thickness,fresh weight and flexural strength of lateral deep fertilization were significantly lower than those of full-layer fertilization by 7.85%,14.18%,4.13%and 2.03%,respectively;The diameter of the second internode,the thickness of stem wall and the bending resistance were significantly lower than those of the whole layer fertilization by 8.15%,9.18%and 18.61%,respectively;The stem wall thickness and bending resistance of the third internode were significantly lower than those of the whole layer fertilization by 16.00%and 16.15%,respectively.The lodging resistance index of side deep lateral fertilization was significantly lower than that of full layer fertilization by 16.60%.The height of gravity center,length of internode,thickness of stem wall,fresh weight of internode and bending resistance of internode were beneficial to the lodging resistance of rice under reduced N application.Lodging resistance indices of 15%and 30%N reduction were 6.19%and 9.52%higher than those of conventional N application.Lodging resistance index showed an increasing trend with decreasing N application rate under full layer fertilization,but there was no significant difference among nitrogen reduction fertilization levels under side deep fertilization.
Rice in cold areasFertilization methodNitrogen reductionLodging resistance