Sjemenarstvo, Vol. 13 No. 3-4, 1996.
Izvorni znanstveni članak
THE STUDY OF CHANGING GENOTYPE STRUCTURE IN CYCLICAL RENEWAL OF SEEDS
Darja Kocjan-Ačko
; Biotehniška fakulteta, Ljubljana, Slovenija
Sažetak
The great phenotypical similarity among numerous lines of "pure" cultivar does not allow the direct study of the suruival of an individual line. Field block trials were conducted from 1985 to 1987 and from 1988 to 1991 near Ljubljana in which survival among lines was simulated using the model of variety mixture. Cultivars of winter wheat (Triticum aestivum L. var. aestivum), cvs. Lonja (L), Nizija (N) and Jugoslavija (J) were grown in conditions of competition as double mixtures: L+N, L+J, N+J, and as a triple mixture: L+N+J. The phenotypical distinction between cultivars in the mixture enabled an assessment of the survival of an individual cultivar. In 1985 "certified seed" (1. generation) was sown in the ratios 600/2:600/2 or 600/3:600/3:600/3 germination seeds per m². In the years 1986, 1988, 1989, 1990 "uncertified home produced seed" was sown in the same proportion among cvs. as the yield produced the previous year. During the growth period herbicides and two N treatments were applied, but no protection against disease or pests was used. Results tested using x²-test showed a statistically significant deviation (P<0.05) in the survival rates of cvs. each year compared with the initial ratios. After the fifth year of cyclical renewal the proportions of yields in mixtures were as follows: L+N = 47:53, L+J = 36:64, N+J = 42:58 and L+N+J=19:32:49. Using the exponent of the annual multiplication the presence of individual cultivar in the mixture after 15 years of cyclical renewal was calculated (L+N= 53:47 , L+J= 18:82, N +J=20:80 and L+N+J=6:18:76). The changes observed arose due to biological influences among cultivars depending on ecological conditions. Degeneration appeared as the proportions of cultivars changed in the course of cyclical renewal of seeds.
Ključne riječi
winter wheat (Triticum aestivum L. var. aestivum); variety mixtures; cyclical renewal of seeds; degeneration; survival
Hrčak ID:
168614
URI
Datum izdavanja:
23.5.1996.
Posjeta: 582 *