THE EFFECT OF N-P-K FERTILIZER DOSAGE ON GROWTH, DEVELOPMENT, YIELD AND ECONOMIC EFFICIENCY OF VIET THANH 213 RICE VARIETIES IN THANH HOA PROVINCE

Abstract

The research was conducted on Viet Thanh 213 rice variety in 2 crops (Spring crop and Summer crop in 2022) in 2 districts of Hoang Hoa and Thieu Hoa, Thanh Hoa province. The experiment included 4 formulas arranged in a randomized complete block design (RCBD), 3 replications, experimental plot area of 20 square meter (4 m x 5 m), embankment, planting density of 45 hills/square meters (Spring crop) and 40 hills/square meters (Summer crop) and 2 seedling/hill. The research results showed that the dosage of N-P-K fertilizer had a clear effect on the growth, development, yield components, productivity and economic efficiency of Viet Thanh 213 rice variety in the Spring and Summer crops in Thanh Hoa province. In the Spring crop, on the basis of 1 ton of  Song Gianh organic fertilizer and 400 kg of lime/ha, the N-P-K fertilizer level was determined to be 90 kg N + 70 kg P₂O₅ + 80 kg K₂O/ha (Hoang Hoa district) and 100 kg N + 80 kg P₂O₅ + 90 kg K₂O/ha (Thieu Hoa district) for the highest actual yield of 67.31 quintals/ha, net profit of 20.444 million VND/ha, marginal benefit cost ratio (MBCR) reached 3.18 times and 67.60 quintals/ha, net profit of 20.048 million VND/ha, MBCR reached 2.67 times. In the Summer-Autumn crop, on the basis of 1 ton of Song Gianh organic fertilizer and 400 kg of lime/ha, the N-P-K fertilizer level in Hoang Hoa district and Thieu Hoa district was 80 kg N + 60 kg P₂O₅ + 80 kg K₂O/ha, giving the highest actual yield of 63.67 quintals/ha, net profit of 18.173 million VND/ha, MBCR reached 3.16 times and 66.33 quintals/ha, net profit of 20.165 million VND, MBCR reached 3.06 times.