Evaluation On The Lodging Resistance Of 421 Rice Germplasm Resources

In this paper,the lodging resistance of 173 rice germplasm resources and 248 early rice varieties were evaluated used the anti-thrust per stem method.On this basis,25 rice germplasm resources which had differences in lodging resistance were as materials.The 3kinds evaluation methods of lodging resistance were compared,which were the anti-thrust per stem method,internode resistance method and lodging index method.The relationship between stem morphological index and anatomical structure with lodging resistance were studied.The main results are as follows:1.There were significant differences in plant height,stem diameter,plant fresh weight,plant dry weight and the anti-thrust per stem of 173 rice germplasm resources.The average anti-thrust per stem was 10.85KPa and the variation range was 2.31 KPa³9.33KPa.15 rice germplasm resources had strong lodging resistance and its average anti-thrust per stem up to22.45 KPa.The lodging resistance of W0016 and Y14177 were very good and the anti-thrust per stem were as high as 36.93 KPa and 39.33 KPa respectively.21 rice germplasm resources had poor lodging resistance and its average anti-thrust per stem less than 5 KPa.2.The average anti-thrust per stem of 248 early rice varieties was 6.59KPa and the variation range was 1.16 KPa¹4.50 KPa.12 early rice varieties had strong lodging resistance and its average anti-thrust per stem up to 11.33 KPa.28 early rice varieties had poor lodging resistance and its average anti-thrust per stem less than 4 KPa.3.The lodging resistance evaluation results of the anti-thrust per stem thrust method and the second internode resistance method had good consistency.There was a significant positive correlation between the anti-thrust per stem and the second internode resistance,and the correlation coefficient was 0.9156^**.4.The third internode resistance,plant height,stem length,stem diameter,panicle neck length,plant fresh weight,plant dry weight,stem and sheath dry weight,bending moment,epidermis and basal cell layer,epidermis and basic tissue thickness,vascular bundles number,cavities number,and small vascular bundle diameter were positively correlated with the anti-thrust per stem and the second internode resistance.The results showed that these traits have a positive effect on the lodging resistance of plants.