陆地棉高品质纤维种质基因库的拓建

Construction of Gene Pools with Superior Fiber Properties in Upland Cotton through Interspecific Hybridization between Gossypium hirsutum and Gossypium Wild Species

采用远缘杂交 ,开展了棉属野生种的高强纤维潜力基因向陆地棉品种转育研究 ,以构建高纤维品质的种质基因库。在适宜的自然条件和人工条件下 ,陆地棉分别与异常棉 (Gossypiumanomalum)、辣根棉 (G .armourianum)、雷蒙德氏棉(G .raimondii)等杂交 ,克服杂交不可交配性、杂种一代的高度不育性等 ,通过多年的回交选择和纤维品质测定筛选 ,培育出了纤维品质基本稳定、农艺性状良好的一批超强的细长绒棉纤维种质系 ,其比强度远超过目前推广品种 ,马克隆值理想 ,如 :来自雷蒙德氏棉的 4 7个后代品系 ,其平均纤维比强度达 34.4 3cN/tex、纤维长度为 32 .2 9mm、马克隆值为 4 .37;来自辣根棉的 4 9个后代品系 :平均比强度达 35 .5 0cN/tex、纤维长度为 33.16mm、马克隆值为 4 .2 9;来自异常棉的 10 1个后代品系 ,比强度达 38.15cN/tex、纤维长度为 33.35mm、马克隆值为 4 .11。通过远缘杂交获得的一批高品质种质系 ,组成了一个高品质育种的亲本群体 ,成为高品质育种的重要基因库。

Studies on the introgression of the super fiber properties from Gossypium anomalum, G.armourianum and G.raimondii into G.hirsutum were carried out to expand genetic basis for improving fiber quality in upland cotton and to construct gene pools with super fiber quality finally. The cross incompatibility between upland cottons and Gossypium species and F 1 sterility have been overcome under the proper environmental conditions. About two hundred elite lines characterized as superior fiber properties were developed from the interspecfic hybrids after more than 10 years successive selection. The entirety of fiber properties in HVICC standard was much superior to commercial island and upland cottons. The averages of fiber strength, length and micronair reading were 34.43 cN/tex, 32.29 mm, 4.37 among 47 G.raimondii lines, 35.50 cN/tex, 33.16 mm, 4.29 among 49 G.armourianum lines , 38.15 cN/tex, 33.35 mm, 4.11 among 101 G.anomalum lines from respectively. In contrast, the averages of fiber strength, length and micronair reading were 29.76 cN/tex, 29.76 mm, 5.51 among 14 elite upland and 35.08 cN/tex, 34.56 mm, 3.50 among 5 elite island cotton cultivars, respectively. The results also showed that the biggest variation in fiber quality was from G.anomalum, in which the strength varied from 30 2 to 50.2 cN/tex and was over 35 cN/tex in more than 70% of the lines, the length from 29.7 to 36.7 mm and over 33 mm in more than 60% lines, and micronair reading from 3.0 to 5.1 and 3.7-4.2 in more than 50% lines. The second biggest variation was from G.armourianum. The strength was from 30.2 to 41.1 cN/tex and more than 50% lines over 35 cN/tex, the length from 29.0 to 35.5 mm and almost 60% lines over 33 mm, and micronair readings from 3.1 to 5.0 and 20% lines in 3.7-4.2. The third biggest variation was from G.raimondii. The strength was from 27.3 to 40.1 cN/tex and more than 40% lines over 35 cN/tex, the length from 29.0 to 35.3 mm and almost 30% lines over 33 mm, and micronair readings from 3.2 to 5.6 and one third lines in 3.7-4.2. The smallest variation was in commercial island and upland cottons. Therefore, it was believed that these three wild cotton species were very useful for cotton fiber improvement and the species, G.anomalum , was better than the others. Meanwhile, it was concluded that it was very hard to improve cotton fiber quality only through intrapsecific crosses. All above lines consisted of the gene pools with superior fiber properties and would play a very important role for upland cotton breeding and cotton genomic research in the future.