Study On Genotypic Differences Of The Characteristics And Their Relation With Yield Of Indica Rice(Oryza Sativa.L)

2001 ~眫{~Li~ Study on Genotypic Differences of the Characteristics and Their Relation with Yield of Indica Rice (Oryza Sativa.L.) Postgraduate: Zhang Chuansheng Supervisor: Professor Wang Yulong (AgrLcolL, Yangzhou University, Yangzhou, 225009) Abstract 46 Indica rice cultivars and hybrid combinations were employed in pot experiment to investigate genotype differences of aboveground and root? characteristics and their relation to grain yield.The results showed as follows: a.The upland and root characters had significantly genotypic differences,the ratio of the maximum to minimum of upland characteristics varied from 1.48 to 1O.6.Dry matter production after heading stage was at the most,then biomass,dry matter production before heading stage,the spiklet number per panicle,yield,the total spiklets,the sink capacity,the panicle number,economic coefficient,1000 grain weight,the filled spikelets percentage by decreasing b.The ratio of the maximum to minimum of root characteristics varied from 1.43-15.82,root activity per spikelet possessed was at the most,then the root dry weight,the total length of adventitious root,the number of adventitious root,the actively uptaking area of root,the total activity of roots, weight per unit of adventitious root, dry weight per adventitious root, activity per unit of root wight,length per adventitious root, the ratio of the maximal length of adventitious to plant high,root the ratio of root dry weight to upland matter dry weight,the diameter of adventitious root,mode root length,maxiznal root length In decreasing. c.The ratio of maximum to minimum of nutrition uptaking characteristics varied from 1.50-3.82,the tatal amount of potassium accumulated was at the most ,then the amount of potassium accumulated before heading,the amount of phosphorus accumulated befor headiug,the total amount of phosphorus accumulated,the amount of nitrogen accumulated before heading,the total amount of nitrogen accumulated,nitrogen content at ripening stage,nitrogen content at heading stage,potassium content at heading stage,phosphorus content at riening 75 stage,potassium content at ripening stage,phosphorus content at heading stage in decreasing. d.High yield indica rice varieties possessed larger sink capcity,higher filled spikelets percentage,larger dry matter acciuuulated after beading stage,higher economic coefficient,larger amount of nitrogen,phosphorus,potassium accumulated and amount of nitrogen accumulated after heading stage;larger number,total length and weigh of adventitious root,higher total activity and actively uptaking area of root than those of low yield varieties. e.The grain yield were significantly positively correlated with the sink capcity, the filled spikelets percentage,the spiklet number per panicle,total V spildets,l000grain weight.sink capcity and the filled spikelets percentage were main factors affecting the grain yield,sink capcity depended on the spildet number per panicle. f.Biomass was the main factor affecting the grain yield.the dry matter production of the population before and after heading had the same...