Investigations into genetics of the harvest index in winter wheat
1994
Moldovan, V. | Botezan, V. | Moldovan, M. (Statiunea de Cercetari Agricole, Turda (Romania))
The paper discusses some aspects related to the genetic determinism of the harvest index in winter wheat that might influence breeding strategies for improved yielding ability. The harvest index heredity mechanisms were studied within a 6-hybrid combinations system including parents P1 and P2, hybrids F1 and F2 and backcrosses BC1 and BC2 for each hybrid combination. The results indicated that the harvested index heredity is ruled by additive, dominating and epistatic genetic effects, function of each specific hybrid combination. The narrow sense heritability coefficients were scored high, ranging between 0.47-0.83, except for one combination of two parents exhibiting close harvest index values. The positive transgression rates for the harvest index scored between 3 per thousand and 271.3 per thousand depending on the genotype. A significant correlation was established between the harvest index and the individual plant yield, the main wheat year yield and TKW. Instead, the correlation with the biological production was poor, indicating, in some cases, that high harvest indices do not necessarily mean high grain yields as well and that they might be the result of low biological productions. The alternative suggested here for improvement of practical breeding works is the application of selection for the harvest index at the level of early generations with all ensuing advantages as well as continued selection performed on more advanced generations for the harvest index combined with the production per se.
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