Study On Mixed Planting Mode With Different Varieties Of Silage Corns In Northern Heilongjiang Province

Silage corn (Zea mays L.) which was one of the most indispensable foundational feed of livestock husbandry had been used most widely all over the world. With the development of cattle and sheep raising, the sown area of silage corn expanded. Northern region of Heilongjiang Province where had great demand for silage corn, was the important base of cattle raising, However, high latitudes, low annual average accumulated temperature and short growing period seriously limited the production of silage corn. At present, in order to reduce the loss, most late-maturing varieties of silage corn planted in the region can not reach the optimum period. The result was that the most varieties of silage corn had bad growth such as bad mature of kernel and low nutrient content, seriously affected the quality of silage. The study based on the situation of the northern region was conducted to determine the effects of different mixed planting modes which compared with monocropping on growth, production and feed quality by testing main agronomic, fresh yield, dry matter yield and nutrient content of mixed societies ,comprehensively evaluated the treatments of mixed planting and monocropping by Milk 2000 index, and finally found out the suitable mixed planting mode of silage corn in the north region of Heilongjiang Province. The result would provide the consult and new ideas of producing silage corn which had high yield and good quality in cold regions of Heilongjiang Province to ensure the healthy and sustained development of agricultural production..designed mixed planting experiment with 1 late-maturing corn ZY32 and 4 early-maturing corns LD13,LD8,HY9,HY8,in order to obtain high yield and quality corn silage in three plant densities and three mixture ratio. protect the healthy and sustained development of agricultural production.The main conclusions of experiments were as following:⒈Compared with monocroping,mixed planting model had no significant effect on plant height, ear height, basilar stem diameter and the quantity of green leaves at harvest time.⒉The fresh yield of mixed planting treatments was lower than late-maturing varieties of monocropping treatments in mixed societies,higher than early-maturing varieties of monocropping treatments in mixed societies;compared with monocroping treatments,mixed planting significantly improved the dry matter yield.⒊The CP, EE and starch content of mixed planting treatments were lower than monocropping treatments of early-maturing varieties, higher than monocropping treatments of late-maturing varieties, the NDF and ADF content of mixed planting treatments were lower than monocropping treatments of late-maturing varieties, higher than monocropping treatments of early-maturing varieties; The CP, EE, NDF and ADF yield of mixed planting treatments were higher than monocropping treatments of early-maturing and late-maturing varieties, the starch yield of mixed planting treatments were higher than monocropping treatments of late-maturing varieties, only when mixture ratio was 1:2, higher than monocropping treatments of early-maturing varieties.⒋With the incresaing density, basilar stem diameter and the quantity of green leaves at harvest time of each corn variety was decreased; plant height and ear height of ZY32,LD13 and LD8 were increased while HY9 and HY8 were increased firstly and then decreased.⒌With the incresaing density, the fresh yield and dry matter yield of each treatments were increased firstly and then decreased; the CP , EE and starch content of each treatment was decreased, the NDF and ADF content of each treatment was increased. With the changes in density, the yield of each nutrient composition had the basical same trend that was increased firstly and then decreased.⒍In each mixed planting treatments, the fresh yield got the maximum when the mixed ratio of late-maturing and early-maturing varieties was 2:1,then was 1:1 and 1:2. The dry matter yield had no significant effect among different mixed ratio.⒎The CP, EE and starch content and yield of most of mixed treatment got the maximum when the mixed ratio of late-maturing and early-maturing varieties was 1:2.The NDF and ANF content and yield of each mixed treatment got the maximum when the mixed ratio of late-maturing and early-maturing varieties was 2:1.⒏The comprehensive appraisal of each treatment was evaluated by Milk 2000 index, the result showed that the treatment of mixed planting by ZY32 with HY9 which planted in density 79500 plants/ha and mixed ratio 1:1 had the highest class score and was suitable to plant in northern Heilongjiang Province.