Study On The Relationship Between Source And Sink In Soybean

Based on the physiology study on high-yield and optimum cultivation of soybean, two soybean CV (JiYu47, JiYu45) under different treatments of planting density and fertilizer application were studied on the formation, characteristics of population source and sink and the relationship between them, and so did the influence of NPK application on them. The results showed that to realize soybean yield over 200kg/mu maximum leaf area index (LAI) should be over 5, the total leaf area duration (LAD) of the whole growth stage should be over 170000mJ.d, the dry matter accumulation should have a reasonable trend, and sink were filled well. The absorption of NPK reached its peak value at seed formation stage . It was important that there were enough NPK to increase source and enlarge sink at this stage. After changing the proportion of source and sink, the result indicated that remaining leaves or pods got compensation in different level. Source had influence on sink, while the sink had feedback to source, and the sink was the main restrictive factor to yield. Adopting rational techniques of density and fertilizer was the key to balance the relationship between source and sink of soybean and gain high yield. Main indices and cultivation techniques of nigh-yield for JiYu47 were as follow: density was 260000 plant/mu, applications of P_>0=, K..O and N at planting were respectively 5. Okg/mu, 5. 73kg/mu, 3.OGkg/nm, top-dressing N was 2.53kg/mu.