| The local germplasm has made great contribution to the maize breeding. Fully excavate the genetic potential and fully develop, utilize the local germplasm is a efficient way to expand the the germplasm genetic base of our country. It is great significant to further enhance level of the maize breeding in China. This research took five circler populations of Huangjin population which were improved by half-Sib recurrent selection and half-Sib reciprocal recurrent selection as material, by the two-site performance test of improvement population's output in one year, simultaneously, using the NC-II genetic design, taking the improvement populations of the Huangjin population's five circle as the male parent, taking Huangzao4, Dan340, Zhong Syn 5, Qi 319, Ye478, Mo17 as testers to match 30 test crosses through one year two-site appraising test of yield combining ability effect, Huangjin population improvement effect was appraised from different angle of a population's output character and the combining ability and so on with recurrent selection. The main results as follows:1.The method of half-half and full-sib recurrent selection could improve Huangjin population ' yield effectively. To compare C0 with C3, the single average plant's yield of Huangjin population was enhanced greatly and reached highly significant probability level; using C4 comparison C3, the yield was increased 2.06%. using every circle of C1-C4 comparison C0, the yield was increased 4.51%,6.66%,12.81% and 15.13% respectively, and the average circle was increased 3.78% .2. From the improvement effect of the yield component, comparing C3 with C0, the main yield characters were increased, the ear length and kernels per row was increasing 14.71% and 17.61%, respectively, both reached highly significant probability level. Comparing C4 with C3, kernels per row, ear length, ear diameter and 100 grain weight was increasing, the number of row per ear was declined slightly. The results indicated that the main yield components were improved. Correspondingly with the enhancement of improvement population, simultaneously . The advantages as follows: the ear to be longer than before, kernels per row be more, 100 grains weight to be higher and the maturing stage to be earlier than before, plant height and ear height to be moderate, the good traits had the high latent utilization in the breeding, but the population also had the insufficiency that the length of ear tip-barrenness has increased and the era was shorted. So the traits as highlight should be improved and enhanced.3. Through the analysis of Huangjin population improved population coefficient of variation ,the results indicated that the coefficient of variation has drop obviously with the increase of improvement circle, the coefficient of variation of the average single plant yield lowered from C0 15.43% to C4 12.80%, but the individual total of average single yield which above 160g was more than C0 obviously, the results showed that the improvement population still maintained the higher genetic variation relatively and had the potential of further improvement. The variation coefficient of improved C4 ear characters from large to small were 100 grain weight, the number of row per ear, kernels per row, ear length, ear diameter, kernel percentage. Therefore, the population had the huge potential in enhancing 100 grain weight and kernels per row.4. The analysis of the average single yield of the 30 test-crosses indicated that the first three high yield test-crosses in the single output were Qi 319 as tester accounted for 2, Mo17 as tester accounted for1; In the first ten high yield test-crosses were Qi 319 as tester accounted for 5, Ye 478 as tester accounted for 3. The lowest three test-crosses respectively were Hangzao 4×Huangjin population C0, Dan 340×Huangjin population C0 and Zhong Syn 5×Huangjin population C0, in the low yield test-crosses Tangsipingtou group (Huangzao 4,Zhong Syn5)as tester accounted for 2. The results indicated that Huangjin population×P population was the strongest heterotic pattern, but Huangjin population×Tangsipingtou group hybrid was the smallest.5. The analysis of the combining ability effect indicated that after Huangjin population was improved 3 circles with the half-sib recurrent selection, the combining ability effect enhanced from -8.613 to 3.804 by C3 compared with C0 and reached highly significant probability level; After 1 circle selected with half-sib recurrent selection, the general combining ability effect enhanced from C3 3.804 to C4 6.91. The results showed the two methods enhanced the combining ability effect of Huangjin population. The analysis of special combining ability effect showed that the special combining abilities of improved Huangjin population×Qi319 had certain enhancement, which developed steadily toward P population×Tangsipingtou, Reid×Tangsipingtou mixed superior pattern. |
