Effects of Growing-microbial Agents on Yield, Soil Nutrients and Heavy Metal Cd of Double Cropping Rice

Li Chao;Xiao Xiaoping;Tang Haiming;Wang Ke;Cheng Kaikai;Tang Wenguang;Yang Guangli;Hunan Province Soil and Fertilizer Research Institute;

Hunan Province Soil and Fertilizer Research Institute

growing-microbial agents;;double cropping rice;;soil nutrients;;heavy metal Cd;;yield

To clarify the effect of growing-microbial agents on paddy bioremediation and fertilization, thisstudy set growing-microbial agent "chenaorunze" as representative material, five treatments including0 kg/hm2(CK), 30 kg/hm2, 60 kg/hm2, 90 kg/hm2, 120 kg/hm2 were set to research the effects of growing-microbial agents on topsoil nutrients, heavy metal Cd and yield of double cropping rice. The results showedthat: rice yield showed an increasing trend with increasing dosage of"chenaorunze", the effective panicle andgrains per spike were the major factors of high-yield; "chenaorunze"improved soil available nutrienteffectively, increased soil supplying nutrient capability; heightened the nitrogen and potassium content of root,promoted nitrogen and potassium in stem transferring to grain, and the capacity of lodging-resistant wasstrengthened as the addition of potassium content in stem;"chenaorunze"could reduce rice Cd accumulationmainly by the way of decreasing soil effective cadmium, and Cd accumulation showed a decreasing trend withincreasing dosage of"chenaorunze", thus, it was beneficial to guarantee the safe production of double croppingrice. The optimum dosage of"chenaorunze"was about 90 kg/hm2 with a better bioremediation and fertilization effect from the perspective of decreasing cost and increasing efficiency, the yield of early and late riceincreased by 12.9% and 12.6% compared with control respectively.