籼、粳超级稻茎秆抗倒支撑特征的差异研究

Difference in Lodging Resistance of Culm Between indica and japonica Super Rice

为阐明籼、粳超级稻茎秆抗倒支撑特征的差异,以当地主栽且具有代表性的2个超级杂交籼稻组合和2个常规粳型超级稻品种为试验材料,在稻麦两熟制条件下对籼、粳超级稻茎秆形态特征、充实性状和力学特性以及弯曲力矩、抗折力、倒伏指数、田间表观倒伏率和实收产量等进行了系统的比较研究.结果表明,1）粳稻实收产量较籼稻高12．30％,差异极显著；基部0~20 cm 节间抗折力极显著高于籼稻、倒伏指数极显著低于籼稻,没有出现明显倒伏现象,而籼稻扬两优6号和两优培九两年平均田间表观倒伏率分别达11．97％和12．50％；2）粳稻基部四个节间弯曲力矩均极显著小于籼稻,抗折力均极显著大于籼稻,最终粳稻基部第1至第4节间的倒伏指数均极显著低于籼稻；3）粳稻各节间长度和株高以及基部节间外径、秆型指数、单穗质量、重心高和相对重心高度均小于籼稻,差异显著或极显著,而穗下节间长/秆长粳稻极显著大于籼稻；4）粳稻六个伸长节间的茎秆粗度和茎壁厚度均小于籼稻,其中,基部第1至第4伸长节间的茎秆粗度达到显著或极显著水平；5）粳稻各节间茎秆干质量均小于籼稻,两优培九各节间叶鞘干质量极显著高于其他3个品种,且粳稻基部第2节间单位节间茎秆干质量略高于籼稻,而基部第1、3、4、5、6节间粳稻单位节间茎秆干质量均低于籼稻；6）粳稻单穴固持力和抗弯阻力均显著或极显著大于籼稻,而按压恢复度显著或极显著小于籼稻.可见粳稻固持抗倒能力较强,籼稻抗倒恢复能力较强,且粳稻能协调实现高产与抗倒,这可能与其弯曲力矩小、抗折力大、株高矮、节间配置合理、重心低以及基部节间物质充实足等有关.

To reveal the difference in lodging resistance of culm between indica and japonica super rice, a field experiment was conducted by using two main representative super hybrid indica combinations and two conventional japonica super rice varieties as materials in the rice-wheat cropping regions.Characteristics of morphology,Filling and mechanics,breaking resistance,bending moment,lodging index,apparent lodging rate in the field and grain yield were analyzed systematically.Results showed that：1）grain yield of japonica rice was significantly higher than that of indica rice,with a rate of 12.30%.For the culm of 0 - 20 cm from the bottom,the bending moment of japonica rice was significantly higher than indica rice and the lodging index followed an opposite trend without lodging,compared to the average apparent lodging rates in the field of 1 1 .97%, 12.50% from 201 1 to 2012 for Yangliangyou 6 and Liangyoupeijiu,respectively.2）For all the four basal internodes,indica rice had significantly higher breaking resistance and lodging index,while bending moment followed an opposite tendency.3）Length of each internode and plant height, outer diameter of basal internode,stalk type index,single panicle weight,height of gravity center and ratio of gravity center height to plant height of japonica rice were lower than that of indica rice significantly,with an opposite trend for ratio of neck internode length to stalk length.4）Culm diameter and wall thickness for all the six elongated internodes of japonica rice were less than that of indica rice,with culm diameter from 1 st internode from the bottom to the 4th internode from the bottom reaching a significant level.5 ）Dry weight of culm of each internode in japonica rice was lower than that of indica rice and dry weight of leaf sheath of each internode in Liangyoupeijiu was significantly higher than that in the other three varieties.Dry weight per unit internode for the second internode from the bottom of japonica rice was slightly higher than indica rice,while the opposite trend was found for the others.6）Retaining force per hill and buckling resistance of japonica rice were greater than indica rice significantly,while recovery after pushing followed an opposite tendency accordingly.Therefore,japonica rice was provided with strong ability of retaining and lodging, and indica rice had strong recovering ability.Moreover,for japonica rice,high yield and lodging resistance can be achieved at the same time, owing to its small breaking resistance, large bending moment, low plant height, appropriate internode charactericstics,low height of gravity center,enough dry matter of basal internode,and so on.