The Transfer Breeding Of Kenaf L23A CMS And The Research Of The Utilization Of Heterosis

Kenaf is to harvest bast fiber or stalk for the purposes, and itst heterosis is up to 35%-40%, but the research of kenaf heterosis started too late, progress slowly. In this study, on the basis of kenaf CMS L23A and the corresponding maintainer, introudced from Guangxi University, we tried to develop kenaf CMS breeding and the utilization of heterosis. The major findings are as follows:1,48 kenaf germplasm were tested cross with CMS L23A (B), and the F1 fertility were identified according to visual and microscopic examination, the result showed that the most country cultivated species of F1 were infertility, so cultivated species of kenaf were expected to breed new kenaf male sterility by many generations directly.2,Two types,AI type and AⅡtype, appeared on the test cross F1,of kenaf male sterility's pollens were observated by microscopy and scanning electron microscopy, and found that AI type pollens didn't have any aperture, the outer wall of the spike was not obvious, like wilting, and didn't have content material longitudinally, so AI type pollens were completely aborted; AⅡtype pollens were malformation, slitting a small amount of contents, incompletely abortion,but the pollens didn't have vitality.3,By five backcrossing, six kenaf male sterility initialy were bred, 992A, 952A, Bt952 (red) A, Bt952 (green) A, Fuhong2A and GA42A. Through surveying the anther cracking rate and self-fruitful rate,the research showed that six kenaf male sterility'sterility all had reach the level of more than 99.5%, and the economic characters were good too. And two F2 populations were built, to observe segregation of fertility, The result showed that non-sterile gene of kenaf CMS was controlded by a single recessive gene.4,6 new Kenaf male sterility and 6 Kenaf restorer were selected, then 36 F1 were obtained according to imperfection double cross design, using the addictive-dominant genetic model(AD model) and statistical analysis, the genetic effect, heterosis and genetic correlation, of plant height, stem diameter, thick skin and other nine major economic traits in those F1 were analyzed systematically.The results showed that: Hybrids on the Kenaf of plant height advantage were not obvious, heterosis were mainly embodied in diameter, bark thickness, stem fresh weight, fresh weight and dry stem weight. In 36 combinations of hybrids, there were 10 combinations yield more than 40% than CK,mainly includes 952A×Xin'anwuci(55.9%), 992A×Feizhoulieye (51.4%), Fuhong2A×Laiyangkenaf(40.9%),Bt952(red)A×Xin'anwuci (63.5%); 16 combinations of yield 25%-40% than the CK,mainly includes 992A×Laiyang kenaf (30.0%), 992A×Fuhong8 (25.5%),992A×KB2 (38.0%), 952A×Laiyang kenaf(26.3%),952A×SCS11-09(39.9%),Bt952(Green)×KB2(25.7%),Fuhong2A×Fuhong8(26.8%),Fuhong2A×KB2(38.2%),Bt952(red)A×Laiyangkenaf(28.1%),Bt952(red)A×Fuhong8(34.5%),Bt952(red)A×feizhoulieye(35.7%),Bt952(red)A×SCS11-09(32.8%),Bt952(red)A×KB2 (36.4%).