Research On Plant Characteristic For Mechanized Harvesting And Chemical Ripening Of Soybean In Relay Strip Intercropping

This experiment was carried out to study the plant characteristic for mechanized harvesting during maturity, the effects of plant characteristic and seed yield and quality with different harvesting time and chemical ripening, and a preliminary test of mechanized harvested soybean had been done in the relay strip intercropping soybean, shade-tolerant and height-yield type soybean variety Nandou12was selected, which afford the fundamental research and technology foundation of the relay strip intercropping soybean. The main research results are as follows:1. The plant characteristic of the relay strip intercropping soybean is suitable to mechanized harvesting, but the effects of plant characteristic and seed yield with different harvesting time are significant. The plants characteristics of Nandou12are suitable for mechanized harvesting, mainly comprising:plant lodging light, the lodging rate is only4.75%; most of the plants are convergence, of which76%for convergence,24%for the semi-open; the plant height is more concentrated,98%of the plant height at40cm or more, and77%of the plant height is concentrate between400-600mm;98%of the lowest pod height at5cm or more, and87%of the lowest pod height at10cm or more; the soybean seed size is more concentrated, the seed weight per is concentrated in between0.15～0.25g; pod is easy dry and threshing but not shattering. The effects of plant characteristic and seed yield and quality with different harvesting time as follows:the100-seed weight is still increasing in mature period, the water content of seed and pot is reduced rapidly, but the water content of stem is reduced slowly; fifteen days after R7, the water seed content decreased to17.13%, and the stem and pod content decreased to36.19%and21.31%; the protein and oil content of seed changed little in mature period; so the time that suitable for mechanized harvesting should be at fifteen days after R7, then plant leaves all off, and a clear sound with shaking, and the seed water content less than25%, premature harvest will not only affect the yield, but also increase the harvesters workload and harvesting losses.2. Chemical ripener can promote soybean leaf dry off and decline the water content of different organ reduced quickly, which create favorable conditions for the mechanized harvesting, but different chemical ripener and ripening time both had adverse influence on the100-seed weight. Ethephon promote leaf dry off worked best, about all leaves were abscission only nine days after R7. Diquat promote the seed water content reduce worked best, at nine days after R7the seed water content achieved the state that is suitable mechanized harvesting, advanced nine days compared with the control, but diquat had the greatest influence on100-seed weight, using diquat ripening at the R7and the seven days after R7both made the100-seed weight very significant decreased23.66%and13.01%compared with the control; ethephon promote the seed water content reduce worked worst, but ethephon had the minimal influence on100-seed weight, using ethephon ripening at the R7and the seven days after R7both made the100-seed weight only decreased9.48%and6.79%compared with the control, but that is different with using ethylene ripening crops will increase yield by many different studies, which may be caused by different ripener concentration and ripening time. The different chemical ripener and ripening time had no influence on the protein and oil content of seed and economic coefficient, all the treatment had no significant compare with the control.3. The quality of mechanical harvesting on soybean, which harvested by Gushen RG20that produced by Lovol company, wasn’t meet the national standard, only the proportion of broken seed was close to national standard. The total loss rate was more than the national standard3.32%, the proportion of cleaning seed was less than the national standard6.49%, the proportion of broken seed was more than national standard1.79%, the proportion of the seed surface is stained with dirt was much more than national standard90.77%. It can clearly be seen that the relay strip intercropping soybean can be machine harvested in Sichuan hilly area, but the rice and wheat harvester’s harvesting quality of soybean was not satisfactory, it is necessary to develop special soybean harvesting machinery.