To investigate the formation mechanism of stalk mechanical strength,clarify the mechanical mechanisms underlying stalk rot resistance,and establish core mechanical indicators for evaluating stalk strength,this study u...To investigate the formation mechanism of stalk mechanical strength,clarify the mechanical mechanisms underlying stalk rot resistance,and establish core mechanical indicators for evaluating stalk strength,this study utilized six maize varieties with different levels of stalk rot resistance including ZD619,HXD88,XZY801,XY696,LS1,and ZH431 as test materials.The density,moisture content,bending strength,rind puncture strength,and elastic modulus of maize stalks at different growth stages were determined,and their intrinsic relationships with stalk rot resistance were analyzed.Our results indicated that the stalk density,moisture content,bending strength,and rind puncture strength were responsive to stalk rot resistance.However,these indicators were in significant correlations with stalk rot resistance only after the physiological maturity of maize.In particular,stalk rind puncture strength exhibited the closest correlation with stalk rot resistance at the late stage of physiological maturity.Stalk density directly affected bending strength and rind puncture strength,and it indirectly affected the elastic modulus.The elastic modulus encompassing both load and displacement can improve the reliability of stalk strength evaluation,serving as the best indicator of stalk toughness.The attenuation amplitude of the elastic modulus was always the largest whether it was caused by the aggravation of the disease,the growth stage delay,or the internode position rise,which significantly improved the sensitivity of stalk strength evaluation.The elastic modulus of maize stalks was correlated with stalk rot resistance from the silking stage to late physiological maturity stage,which not only effectively improved the accuracy of stalk strength evaluation but also was beneficial to improving the efficiency of maize variety selection.In conclusion,the elastic modulus of maize stalks can be used to evaluate the maize stalk strength truly and accurately.Especially in the region with a high stalk rot incidence,it was beneficial to improving the breeding efficiency of the maize varieties suitable for mechanical harvesting.展开更多
文摘To investigate the formation mechanism of stalk mechanical strength,clarify the mechanical mechanisms underlying stalk rot resistance,and establish core mechanical indicators for evaluating stalk strength,this study utilized six maize varieties with different levels of stalk rot resistance including ZD619,HXD88,XZY801,XY696,LS1,and ZH431 as test materials.The density,moisture content,bending strength,rind puncture strength,and elastic modulus of maize stalks at different growth stages were determined,and their intrinsic relationships with stalk rot resistance were analyzed.Our results indicated that the stalk density,moisture content,bending strength,and rind puncture strength were responsive to stalk rot resistance.However,these indicators were in significant correlations with stalk rot resistance only after the physiological maturity of maize.In particular,stalk rind puncture strength exhibited the closest correlation with stalk rot resistance at the late stage of physiological maturity.Stalk density directly affected bending strength and rind puncture strength,and it indirectly affected the elastic modulus.The elastic modulus encompassing both load and displacement can improve the reliability of stalk strength evaluation,serving as the best indicator of stalk toughness.The attenuation amplitude of the elastic modulus was always the largest whether it was caused by the aggravation of the disease,the growth stage delay,or the internode position rise,which significantly improved the sensitivity of stalk strength evaluation.The elastic modulus of maize stalks was correlated with stalk rot resistance from the silking stage to late physiological maturity stage,which not only effectively improved the accuracy of stalk strength evaluation but also was beneficial to improving the efficiency of maize variety selection.In conclusion,the elastic modulus of maize stalks can be used to evaluate the maize stalk strength truly and accurately.Especially in the region with a high stalk rot incidence,it was beneficial to improving the breeding efficiency of the maize varieties suitable for mechanical harvesting.
