The evaluation of maize inbred lines as donors of favourable alleles in the improvement of yield components of an elite SC hybrid

Abstract

The aim of this study was to identify which of inbreds of different origin may be useful donors of favourable alleles in the improvement of the quantitative traits of the elite single cross hybrid. Ear length, kernel row number and kernels per row were investigated. Grain yield components in six inbred lines and their 15 hybrids were determined on the basis of field trials set up in a randomised block design with five replications and two years (1997 and 1998). All inbreds showed positive and significant μG values for all traits. The inbred ZPLB380 expressed the highest significant value of this parameter and can be useful in the improvement of the kernel row number. This inbred was more closely related to the parent of the elite hybrid Fu4. The improvement of the kernel row number should be carried out by selfing the hybrid A654 x Fu4. The ear length, kernel row number and kernels per row could be improved together by backcrossing the hybrid A654 x Fu4 to the inbred ZPLB368. All investigated inbred lines were shown to be more genetically related to the inbred parent Fu4 by the relation [(P2xPw)-(P1xPw)+(P1-P2)/2] (Dudley, 1987a). These results suggest that inbred lines can be used as donors of favourable alleles in the improvement of grain yield components of the elite SC hybrid. On the bases of obtained results the inbred line ZPLB368 was found to be the best potential donor for improvement of the elite hybrid A654xFu4.

Izvršena je procena linija donora, kao izvora novih poželjnih alela za komponente prinosa zrna, koji se ne nalaze kod linija roditelja elitnog hibrida ili su kod roditeljskih inbridovanih linija elitnog hibrida već fiksirani nepoželjni aleli. Sve četiri inbridovane linije, potencijalni donori, su imale značajne vrednosti parametra μG, tako da se mogu koristiti kao izvor novih poželjnih alela u povećanju prinosa zrna hibrida A654xFu4, popravkom komponenata prinosa (broja redova zrna, broja zrna i dužine klipa). Inbridovane linije, donori, su imale različitu relativnu frekvenciju poželjnih dominantnih alela za popravku ispitivanih komponenata prinosa zrna. Popravku je potrebno vršiti putem povratnih ukrštanja ili samooplodnje hibrida ovih linija sa roditeljskom linijom Fu4, u zavisnosti od linije donora i od osobine, jer je srodnost svih linija donora veća sa Fu4 nego sa A654.