Studies On Yield-increasing Potential Of High-yield Hybrid Rice And Dominant Properties In Culm Of Hybrid Combination

In order to probe into yield-increasing potential of high-yield hybrid rice, relationship between growing period, development of leaves and tiller, dry matter accumulation and yield composition of Liangyoupeijiu was comparatively analysized with Shanyou 63, Peiliangyou 288 and their parents as controlls ,under different fertilizer application.At the same time, relationship between component, morphological and correlative physiological index of culm and lodging resistance was studied with combinations between wild rice sterile line from Hainan and nonglutinous rice from Anren, Wuyujing215, 199 and their parents.The results were as follows:1. Comparsion in growth dynamics of high-yield hybrid rice under different fertilizer application.Hybrid rice had approximate growing period under different fertilizer application.Development of leaves and tiller was the fastest and areas of the uppermost three functional leaves were the largest in all materials under higher fertilizer application.As far as Liangyoupeijiu ,the whole growing period was the longest(especially,it had longer vegetation growth and grain-filling period), and occurrence of tiller was earlier and faster, tillering ability was the strongest,areas of the uppermost three functional leaves were the largest.All these showed that better morphological characters, larger photosynthetic area, stronger photosynthetic period and grain-filling period were important biological base for high-yield hybrid rice Liangyoupeijiu.2. Comparsion in biological yield and economic characters of high-yield hybrid rice under different fertilizer application.Biological yield of hybrid combinations was higher than those of their parents under different fertilizer application^ showed that heterosis of hybrid could be exterted under different fertilizer application. Liangyoupeijiu had highest biological yield, more effective panicles under higher fertilizer application;But Shanyou 63 had highest biological yield under moderate fertilizer application;economic efficient of Liangyoupeijiu embodied heterosis(amount to 6.75% and 3.02%), average number of primary branches, grains per panicle, more effective panicles than those of Shanyou 63 under higher and moderate fertilizer application,But Peiliangyou 288 had most grains per panicle under lower fertilizer application.All these showed that super-hybrid rice Liangyoupeijiu exterted its heterosis and harmonized the relationship better between grains per panicle and effective panicles only under higher fertilizer application.3. Comparsion in morphological and anatomical traits of culm in high-yield hybrid rice under different fertilizer application.Diameter.wall thickness,areas of transverse section and wall of basal internode were the largest under higher fertilizer application,hybrid rice is superior to their parents and Liangyoupeijiu is the largest in these aspects.Especially,heterosis of wall thickness and area achieve 19.4%, 17.1%. Liangyoupeijiu had thicker mechanical tissue in vascular bundle sheath, larger auto-fluorescence intensity of lignin.AU these showed that excellent anatomical characters in basal internode, higher lignin content, thicker wall were morphological base of high-yield fertilizer tolerance and lodging resistance for Liangyoupeijiu.4. Comparsion in ability of lodging resistance of culm in distant hybridcombinations...