Determination of Some Agronomical Characteristics and Hybrid Vigor of New Improved Synthetic Varieties in Sunflower (Helianthus annuus L.)

Abstract

This study was conducted in order to improve new synthetic varieties with high yielding ability and to evaluate hybrid vigor for certain agronomical traits of these synthetics. Three Syn Is, each composed of four inbred lines, (Syn IA. Syn IB. Syn IC) and one Syn 1 derived from twelve lines (Syn ID) were formed artificially by inter crossing. Four experimental Syn Is, their parentel mixtures (Syn O's) and two check varieties (open pollinated Vnimik-8931 and commercial hybrid Sunbred-281) were evaluated in the replicated field trials under Bursa conditions without irrigation in 1995. 1996 and 1997. The rates of heterosis observed for plant height, head diameter. seed number/head, 1000-seed weight, seed weight/plant (head) and seed yield/ha were found as 11.2. 14.7. 35.8. 15.7. 59.4 and 65.7 % respectively.