高粱穗瓣籽粒拉伸力学特性研究

针对高粱在机械收获过程中的脱粒不净问题，研究了高粱穗瓣与籽粒的拉伸力学特性。试验选取了“辽杂37号”“晋杂34号”和“兴湘梁2号”3个品种的高粱为研究对象，以不同收获期、生长部位为试验因素，以拉伸断裂力为试验指标，研究各因素对高粱穗瓣、籽粒断裂时拉伸断裂力的影响规律。结果表明，品种、收获期、生长部位对高粱穗瓣、籽粒拉伸断裂力的影响极显著，影响拉伸断裂力的主要试验因子是生长部位。拉伸断裂力的大小与高粱自身的生长部位有关，高粱穗瓣断裂所需的力随着生长位势由上到下逐渐增大，变化范围2.479~9.627 N，且高粱籽粒拉伸断裂力随生长位势的变化趋势与穗瓣基本相似，变化范围2.386~8.314 N。3个品种中，“兴湘梁2号”的承载能力最强，所需拉伸断裂力最大。不同收获期的高粱有着不同的力学性质，综合来看，高粱收获宜选择在蜡熟期。该研究为高粱收获装备的研制优化与适时收获提供了理论参考。 

Tensile Characteristics of Sorghum Spikelet and Grains

In order to solve problem of unclean threshing of sorghum during mechanical harvest，tensile mechanical properties of sorghum spikelet and grain were studied.In this experiment，three varieties of Liaoza-37，Jinza-34 and Xingxiangliang-2 were selected as research objects.Different harvest periods and growth position were taken as experimental factors，and tensile fracture force was taken as experimental indexes to study influence of various factors on tensile fracture force during grain and spikelet of sorghum.Results showed that variety，harvest time and growth position had significant influence on tensile fracture force of sorghum spikelet and grain，and main test factor affecting tensile fracture force was growth position.Tensile fracture force was related to growth potential of sorghum itself.The force required for sorghum spikelet fracture increased from top to bottom with growth potential，and variation range was from 2.479 N to 9.627 N.Moreover，variation trend of sorghum grain tensile fracture force with growth position was basically similar to that of spikelet，and variation range was from 2.386 N to 8.314 N.Among three varieties，Xingxiangliang-2 has the strongest bearing capacity and the greatest tensile fracture force.Mechanical properties of sorghum at different harvest times were different.In general，sorghum should be harvested at dough stage.This study provides a theoretical reference for research and optimization of sorghum harvesting equipment and timely harvest.