Optimal Mixed-Sowing And Row Space-Allocation Mode Screening And Economic Benefit Analysis Of Alfalfa Planting In Ningxia Yellow River Irrigation Area

Aiming at the problems of low yield,poor quality and low profit in the production of alfalfa commodities in the irrigation area of Ningxia in recent years,In order to improve the economic benefits of alfalfa grassland in Ningxia Yellow River Irrigation District,the effects of seeding rate and mixed seeding mode,seeding rate and row spacing form mode on alfalfa production performance and forage nutritional quality were tested and studied.The results showed that:(1)The seeding rate and mixed seeding mode had significant effects on agronomic traits and nutritional quality indexes of alfalfa(P<0.05).Sowing amount and row spacing pattern had significant effects The four-year hay yield with treatment X1Y4(seeding rate of 13.5 kg/hm2,1+3 inter-row mixed seeding)was significantly higher than other treatments,which was reaching to 66.53 t/hm2.The treatment X1Y2(seeding rate of 13.5 kg/hm2,1+1 inter-row mixed seeding)could cause the highest relative feeding value,which was 180.12.Based on the principal component analysis of 6 nutritional quality indexes of alfalfa,and the grey correlation comprehensive evaluation of 5 agronomic traits and 6 nutritional value indexes,it was concluded that the optimal combination of seeding rate and mixed seeding mode was 13.5 kg/hm2 and 1+2 rows under irrigation.(2)The seeding rate and row spacing form mode had significant effects on agronomic traits and nutritional quality indexes of alfalfa(P<0.05).The four-year hay yield with treatment M2N3(seeding rate of 18 kg/hm2,two narrow and one wide(15 cm+15 cm+20 cm))was significantly higher than other treatments,which was reaching to 74.78 t/hm2.The relative feeding value of treatment M2N2(seeding rate of 18 kg/hm2,line 20 cm)was the highest,which was up to 183.68.Based on the principal component analysis of 6 nutritional quality indexes of alfalfa,and the grey correlation comprehensive evaluation of 5 agronomic traits and 6 nutritional value indexes,it was concluded that the optimal combination of seeding rate and row spacing form under irrigation was 18kg/hm2 and two narrow and one wide(15 cm+15 cm+20 cm).(3)According to the fitting results,the plant height of alfalfa can be used to predict the alfalfa yield more accurately.Derived from the formula,the income model with the optimal planting pattern for seeding rate and mixed seeding under irrigation conditions was P=2240×(0.12x-5.19)-0.12 ×I.The income model with the optimal planting pattern for seeding rate and row spacing form under irrigation conditions was P=2240×(0.09x-2.34)-0.12×I,It had been verified that the income model with seeding rate and mixed seeding pattern had better stability,and the measured value of economic returns in 2020 was significantly different from the estimated value.The income model with seeding rate and row spacing form pattern was the extremely stable model,there was a small difference between the measured value and the estimated value of economic benefits in 2020,which could be applied to actual production.By the analysis of seeding rate and mixed seeding mode,seeding rate and row spacing form mode,a forecast model of economic benefits of alfalfa grassland was established.Through the use of comparison of the measured data in 2020 with the estimated data,and it was concluded that under the combination mode of seeding rate of 18 kg/hm2 and two narrow and one wide of(15 cm+15 cm+20 cm),the economic profit model P=2240×(0.09x-2.34)-0,12 × I could better predict the actual economic profit of alfalfa.