Studies Of The Nutritive Quality Improvement Breeding Of Astragalus Adsurgens Pall

A study of Pepsin?cellulase technique for determining forage Invitro dry matter di- gestibility was made firstly; then,we predicted the effect of the breeding method to devel? ope a new variety with high digestibility by the space mutation technique;and explored the feasibility of the breeding project to improve the nutritive quality of the cultivated A. ad- surgens Pall, by cross ?breading with the wild A. adsurgens Pall.. The results were ob- tained as follows: The pepsin?cellulase technique can reflect the digestibility quality difference of vari- ous forage samples finely, the correlation between IVDMD and nylon bag digestibility reached significant difference at 1% level(r0. 8907) ,linear regression equation is:Y7. 97+0. 68X(Y:nylon bag digestibility;X:IVDMD by the enzymolysis technique). The cor- relation between the digestibility and the leaftem ratio of A. adsurgens Pall, reached sig- nificant difference at 5% level(r0. 7584) ,consequently, we can screen the forage digesti- bility phenotype of A. adsurgens Pall, by the leaf?stem ratio instead of the digestibility, linear regression equation is :Y44. 93+5. 25X(Y:nylon bag digestibility;X:leaftem ratio). Dry seeds of A. adsurgens Pall, were carried by recoverable satellite(RS) for space mutation. The genetic parameters of M2 generation of it carried by RS have been calculat- ed; the results indicated that the heritability(h2)of digestibility of A. adsurgens Pall. æ…”e Nan Mm Quan.han xiliLing?was 45. 6o and 56. 4% respectively, furthermore, the ge- netic variation was caused by additive effect. For this reason, we should use mass selection to screen Out the samples qualifying for the breeding objectives and develope a new variety of A. adsurgens Pall, with high digestibility. Theoretically, the digestibility of Hean Minquan nd?ShanXiluLianghould be improved 5. 99% and 6. 5170o respectively by up- ward digestibility phenotype selection of one generation of M2. The digestibility.CP NDF. ADF andADL quality character of the wild A. adsurgens Pall, is better than those quality character of the cultivated A. adsurgens Pall. ,only leaf stem ratio is lower at the period of vegetative growth, squaring stage is a turning point that most of the nutritive quality parameters varied evidently, therefore, we should select this period before squaring stage to be harvesting period; meanwhile, we should improve the nutritive quality of the cultivated A. adsurgens Pall, by crossreeding between the wild and the cultivated Astragalus adsurgens Pall.