The Differences Of Stem Characters Analysis Of Wheat Varieties With Different Height Field And Lodging Resistance

The stem breaking-resistant strength is the basis of the lodging-resistance capability,and it is closely related to stems elasticity,hardness,circularity and material transport.This paper studied culm tissue,physiological and physical characteristics and the relationship with breaking-resistant strength by useing 3 plant height field(dwarf-stalked: 60-70 cm,half dwarf-stalked: 70-80 cm,long-stalked: 80-90cm)and 12 winter wheat varieties(dwarf and lodging resistant(DLR): ‘Aikang58’ and ‘Zhoumai17’;half dwarf and lodging resistant(HDLR): ‘Zhoumai20’ and ‘Zhoumai18’;long and lodging resistance(LLR): ‘Zhoumai30’ and ‘Xuke1’;dwarf and lodging susceptible(DLS): ‘Zhongmai895’ and ‘Xinmai18’;half dwarf and lodging susceptible(HDLS): ‘Yanzhan4110’ and ‘Xinmai26’;long and lodging susceptible(LLS): ‘Xuke196’ and ‘Yannong999’)under field condition.The purpose of this study was to identify and select the desirable traits of high lodging-resistance varieties,as well as the major stage,factors and influence degree of stalk strength.Provide theoretical basis for wheat high yield cultivation,variety breeding and mechanized production.The main results are as follows:1)According to the study on morphology character,in the same plant height field,the primary two internodes,the proportion of(1+2)internode in total length,total length of internode,reduction of wall thickness and gravity of lodging susceptible varieties were higher than lodging resistant varieties,but the different was not significant.The wall thickness of lodging resistant varieties were lower than lodging resistant varieties.In the same lodging resistance varieties,gravity,total length of internode grows over time,and there was no significant difference between other indicators.2)According to the study on the stem physiological index of several inclusions after jointing stage.the total sugar content,potassium content and nitrogen content in stem of different lodging resistance varieties showed a consistent trend with the growth period.But the lodging resistant varieties had a higher total sugar content.The total sugar accumulation of lodging resistant and easy lodging-varieties was concentrated in jointing stage to flowering period and flowering period to filling stage,respectively.The total sugar accumulation at filling stage show up that long-stalked> half dwarf-stalked> dwarf-stalked.The lodging resistant varieties had a lower amount than lodging susceptible varieties from filling stage to maturation stage,The potassium content of dwarf-stalked varieties was higher than long-stalked varieties between different plant height varieties,but the difference was not significant.Lodging susceptible varieties with high nitrogen accumulation and translocation in growth stage.There was no significantly difference between different plant height varieties.The total nitrogen content of stem plays a major role in dwarf varieties,but in tall varieties are total sugar content and the total potassium content by path analysis.According to the ratio of several elements,lodging resistance varieties have higher carbon nitrogen ratio and carbon potassium ratio,relatively low nitrogen potassium ratio.The same lodging resistance varieties between plant height ratio had no significant difference between each element.3)According to the study on mechanics of crop stalks,the bending strength,elasticity modulus and flexural rigidity showed a trend of increasing first and then decreasing with the stage.Relative to lodging susceptible varieties,lodging resistant varieties have the higher elasticity modulus and flexural rigidity,but there was no difference of inertia moment in different lodging resistance varieties.There’s no significant difference in the same lodging resistance and different pant height varieties.4)According to the study on breaking-resistant strength in different plant height and lodging resistance,lodging resistant varieties had the higher breaking-resistant strength,the difference reached an extremely significant level at filling stage(P<0.01).Through the correlation analysis of stems strength related traits and breaking-resistant strength,in anthesis stage,the significant correlation index with breaking-resistant strength were total soluble sugar,total nitrogen and wall thickness(P<0.05);in filling stage the significant correlation index with breaking-resistant strength were wall thickness,flexural rigidity,total soluble sugar,external diameter and inertia moment(P<0.05);In mature stage,the significant correlation index with breaking-resistant strength were flexural rigidity,wall thickness,bending strength,inertia moment and elasticity modulus(P<0.05).Path analysis showed that,although some indexes were significant correlated with breaking-resistant strength,the effect of the anti-bending force was very weak,and other indicators had a significant impact on bending force.In anthesis stage,the major impact index was the total soluble sugar;in filling stage,the major impact index was the wall thickness;in mature stage,the major impact index was flexural rigidity and bending strength.Therefore,improving stem pole substantial degree and wall thickness was worth practicing and continuing to study of lodging-resistant breeding.5)By comparing the yield-related factors of different plant height of lodging resistant varieties,kernels and yield increased with the increase of plant height.The results showed that under the premise of ensuring the lodging resistance of plants,the long-stalked and half dwarf-stalked varieties had higher production potential than the dwarf varieties.