The Photosynthesis,Dry Matter Accumulation and Translocation Characteristics of Spring Maize Under High Yield Cultivation(≥15 000 kg/hm~2)

The Zhengdan 958 was grown under high yield cultivation(HY) and routine cultivation(CK) in 2009-2011 and photosynthesis,dry matter accumulation and translocation characteristics of spring maize were analyzed to reveal physiological mechanism of yield formation under high yield cultivation and provide the theoretic references for high yield cultivation and super high yield cultivation of spring maize.The results showed that the high yield spring maize reached 15 000 kg/hm2 stably in three years and had the average yield of 16 086.8 kg/hm2,increased 52.8% than CK.Compared with routine cultivation,the high yield spring maize had the following features: the leaf area index was higher and declined slowly,the maximum LAI was 6.62 and kept beyond 3.2 in maturity stage;the SPAD value,net photosynthetic rate(Pn),stomatal conductance(Gs) and transpiration rate(Tr) per unit land area were higher and kept bigger after silking stage;the assimilation amount of dry matter in vegetative organs(stems,leaves and sheaths) in anthesis(AADMVOA) and translocation amount of dry matter in vegetative organs after anthesis(TADMVOAA),translocation ratio of dry matter in vegetative organs after anthesis(TRDMVOAA),contribution of dry matter translocation amount in vegetative organs to grains after anthesis(CDMTAVOAA) were significantly increased by 22.44% and 114.1%,46.56%,42.68% separately.To achieve high yield and super high yield,spring maize should have a high yield population and higher photosynthetic efficiency and longer period of photosynthetic functional leaves,and increase the assimilation and translocation amount of dry matter in vegetative organs,as well as promote the translocation ratio of dry matter in vegetative organs after anthesis.