The Study On Planting Effect Of Peanut-cassava Intercropping And Straw Mulching In Upland Red Soil Of South Hill

Two experiments of different intercropping pattern of cassava (Arachis hypogasa)with peanut (Manihot esculenta crantz) and models of straw mulching were conducted inred soil of south hill in china. The optimal production technology of cassava-peanutintercropping was discussed, grain yield, soil traits and decomposition and nutrient ofstraw in different models of straw mulching were analyzed. The results and conclusionswere as follows:(1) There were negative effects on peanut of cassava in different cassava-peanutintercroppings. The space length of negative effects was40.0cm, and the biggest negativemarginal distance was187.0cm. The grain yield of peanut did not affected by cassavawhen the planting spacing of cassava was374.0cm. The optimal production technology ofcassava-peanut intercropping was found in the research, the pattern of wide rowintercropping was better and ratio of cassava and peanut was1:9.(2)The effect of straw mulching was important in different intercropping pattern ofcassava with peanut. Straw mulching in spring could improved grain yield of cassava andpeanut. Compraned with A0(no straw), the grain yield of peanut in A2(straw mulchingwith rot stem bacteria) and A1(straw mulching) was increased significantly by6.70%-10.29%, and cassava was enhanced significantly by38.67%-39.75%,but there wasnot remarkable different between A1and A2. This showed that the yield of cassava andpeanut was not effected by rot stem bacteria.(3) The straw mulching can significantly increase the soil biological activity andwater content, but especially impact0-20cm depth of soil water(in the continuous droughtcan prolong drought days7-9days).(4) The straw mulching can increase soil available nutrient accumulation, Compranedwith A0(no straw), covered+rotten straw stalk processing (A2) and straw mulchingtreatment (A1) in addition to the soil pH decline, other soil nutrients (organic matter,available phosphorus, available potassium and alkaline hydrolysis nitrogen) content tosome extent, among them with available k increased most, significant differences (p <0.05). And adding corrosion is advantageous to the straw stalk bacteria release nutrients,promote the accumulation of soil available nutrients.(5) The decomposition of straw was quickly when straw mulching was applied inthree months in spring, and the decomposing rate was42.7%-46.3%. then, it was50.20%-52.55%when the exmperiment was end (eight months). Nutrient releasing ofstraw was occurred in three months after straw mulching, releasing rates of N (nitrogen), P(phosphorus), K (potassium) were47.8%-51.7%,50.0%-52.0%,85.0%-85.4%. It indicatedthat K> P> N. However, straw mulching with rot stem bacteria could improved releasing rates of N and P, but K was not.(6) The economic benefit of cassava-peanut intercropping was increased in strawmulching. Compraned with the A0, The incomes of A1and A2were increased by3334.2RMB/hm2and3677.9RMB/hm2, respectively, and the growth rate were19.60%and21.62%, respectively. And compraned with peanut planting alone (traditional farming),The incomes of A0, A1and A2were increased by6974.0RMB/hm2,10308.2RMB/hm2AND10651.9RMB/hm2, respectively, and the growth rate were69.46%,102.66%and106.08%, respectively.