Effects of February Orchid Application on Dry Matter Accumulation and Nutrient Uptake in Maize and Soil Nutrient Status

A pot experiment was conducted to investigate the effects of incorporation February Orchid,applied as green manure,on dry matter accumulation and nutrient uptake in maize and soil nutrient status. There were five treatments,control,two green manure incorporation rates( 50% G and G),conventional fertilizer application rate( F) and green manure combined with fertilizer( G + F) in the experiment. The results showed that green manure application could supply a certain amount of nutrients. The biomass,grain yield and nutrient uptake of maize were significantly increased after green manure application,and were enhanced with the application rates as well. The biomass and N,P,K absorption in the treatments of 50% G and G were similar to those in F and G + F at jointing stage,indicating that sole green manure applications could satisfy the normal growth of maize before jointing. Com-pared with the F treatment,green manure combined with fertilizer application could further benefit the nutrient uptake and the grain yield of maize,i. e.,the G + F treatment increased the N,P,K uptake of maize at maturity by 10. 8%,28. 1%,45. 8%,respectively,and increased the yield by 9. 1%. Green manure application might have effects on the root growth and P,K uptake of maize,resulting in that root biomasses and root to shoot dry weight ratios were increased and relative P and K absorption rates were higher than N absorption rate in all treatments incorporated with green manure. Treatments with sole green manure( 50% G and G) depleted the soil N min and Olsen-P, while the soil N min,Olsen-P,and NH 4 OAc-K were enhanced remarkably in the G + F treatment,showing that green manure combined with fertilizer application could effectively improve the soil nutrient status.