Studies On Pedigree Relative And Agronomy Character Evolution And Its Space-time Distribution Of Economic Traits In Sea Island Cotton (G.barbadense L.) In South XinJiang

Xinjiang Tarim, which being abundant resource of sunlight and heat, is thelargest production base of sea-island cotton where the proportion is about 85% in ourcountry. But it locates the furthest north of sea-island cotton cultivated area. Heat quantitybecomes the one of main confined factors of low fiber strength. 1. Character evolves and pedigree relative of cultivars are analysis. 13 of 14 cultivarsderived from central Asian-Egyptian type sea-island cotton 9122И. The main breedingmethods are pedigree selection and single cross .From the results, inheritance foundation isnarrow. The trends of main traits is that fiber quality is enhanced, especially strength,resist-diseases gain breakthrough, lint percentage is increased, the change breadth of bollweight is slight. Boll weight is basic ecotype. Plant type becomes zero-fruit-branch withlimited long-branch and long stem from intensive type. Plant height is heightened. 2. Studies on space-distribution of economic characters on cotton (Xinhai 21) show:The differences of cotton boll position in the same plant result in differences in economiccharacters. Traits are advantages in middle sites in plant, except for lint percentage and Mic,and the first boll is superior to that of hypo-site. 8-15 nodes are main position formingyield per plant. The first boll of 9-15 nodes has intensively opener. The result of clusteringand comparing is 8-13>2-7>14-18 in space distribution. 8-10 nodes are the most sensitiveposition where boll development period is key in fertility culture and breeding. 3. Analysis of correlation and directly path presents there are notable positivecorrelation between yield per plant and height,node number,boll number,boll weight, ofwhich the direct function of the boll number per plant is maximum, boll weight is second,and the indirect function caused by boll number of height and node number is larger.Comparison space-time distribution of boll-forming ability in different height shows thatboll number and weight of the tall plant is marked superior to that of medium and shortplant. The low's boll mainly centralizes in the first boll position in middle and low sites.There are many nodes and bolls in tall, and its boll weight is large. Especially the rate ofboll setting hypo-site is larger than the short. 4.The ideal percent of space-time distribution of boll number is before July,1(15-20%),July,1-20(60-70%), July,20 onwards(15-20%), 2-5 nodes(20%), 6-13 nodes(60-65%),upwards 14 nodes(15-20%), the first boll(65-70%), hypo-site(30-35%), respectively.