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Protein Content Per Grain The data (Table 2) confirm that both winter lines (F310-C3-4 and F21-76) are superior in absolute protein content than spring wheats. This proves their superior efficiency in nitrogen metabolism. The autumn sown winter parental lines had more protein per grain in comparison to spring sown parents. This is probably due to late maturity and incomplete development of grains in spring sowing. Protein per grain in autumn sown F1 hybrids does not reach even to the level of low grain protein content parent. Whereas, in spring sowing some of the crosses displayed partial dominance and the others heterotic effect for protein content per grain. Differences between the reciprocals of F1 and F2 populations for protein per grain are negligible and nonsignificant. This reflects that absolute protein content is not affected by the cytoplasm. All the combinations with a line F21-76 of F1 population, showed high mean values for absolute protein content. This indicates the genetical superiority of line F21-76 for protein per grain. The mean values of protein per grain in F2 generations of all the hybrids are low in comparison to F1 generations in both the seasons. This tendency of increase in protein percentage and decrease in protein per grain suggests that in segregated populations the small size and shrivalled seeds were developed. Estimates of heritability and genetic advance in autumn sown F2 populations is considerably high as compared to spring sown population, indicating possible genetic diversity. The F2 populations of almost every cross approached to normal distribution, suggesting polygenic control of the triat. Since heritability and expected genetic advance for this trait in autumn sown F2 population is quite high as shown in Table 3, significant gain could be achieved through selection in future generations. On the contrary low heritability and low genetic advance in spring sown F2 populations indicate that the character could be transmitted to future generations, however, no significant gain could be achieved through selection in early generations. These results are in accordance with LARIK (1978) and SOOMRO & LARIK (1981). References CEAPOIU, N., N. EUSTATlU. G.H. ITTU & N.N. SAULESCU 1975. Proc. 2nd. Int. Winter Wheat Conf. Zagreb, Yogoslavia: 362-366. COWLEY, C.R. & D.C. WELLS 1980. Crop Sci. 21: 55-58. JOHNSON, V.A., P.J. MATTERN, J.W. SCHMIDT & J.E. STROIKE 1972. Proc. 1st. Int. Winter Wheat Conf. Ankara, Turkey: 110-126. KERTESZ, Z., MATUZ, J. BARABAS, Z. 1980. Cereal Res. Comm. 8(2): 381-384 KOUAME MIEZAN, E.G. HEYNE and K.F. FINNEY 1977. Crop Sci. 17(4): 591-593 LARIK, A.S. 1978. Genet. Agr. 32: 237-244. LARIK. A.S., K.A. SIDDIQUI& A.H. SOOMRO 1980. Pak. J. Bot. 12(1): 31-41. SHAHANI, N.M. 1980. Ph. D Dissertation, Inst. of Agronomy, Nicolas, Romania: 1-144. SOOMRO, B. & A.S. LARIK 1981. Genet. Agr. 35: 263-274. |
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