GENETIC EVALUATION FOR SEED YIELD AND ITS COMPONENT TRAITS IN SUNFLOWER (HELIANTHUS ANNUUS L.) USING LINE × TESTER APPROACH

Abstract

Sunflower is a vital oilseed crop, but yield improvement remains a major objective. Exploring germplasm and exploiting non-additive gene action can help overcome yield limitations and identify superior parental lines and crosses for hybrid development through GCA and SCA. Four parental lines (A-1, A-2, A-3, and A-4) were crossed with three testers (B-1, B-2, B-3) in a line × tester fashion to generate F0 seeds. These seeds were planted using a randomized complete block design (RCBD) with three replicate plots in the field to ensure unbiased results. Data on various growth and yield parameters is collected and analyzed using Analysis of variance and combining ability analysis. Lines A-3 and A-4 and tester B-3 demonstrated consistently positive GCA effects for several traits, signifying their broad genetic value for hybrid development. The hybrid A-4 × B-1 emerged as the top performer, exhibiting exceptional SCA effects in days to flowering, seed yield per head and height of the plant, indicating exceptional compatibility between these parental lines. Lines A-3 and A-4 displayed significant positive GCA effects for key parameters like head diameter and seed yield. Tester B-3 also contributed to enhanced yield traits in hybrid combinations. Lines A-3 and A-4, tester B-3, and hybrid A-4 × B-1 emerged as promising parents for sunflower hybrid development due to their superior GCA and SCA effects. These findings offer valuable resources for future breeding programs that enhance sunflower yield and productivity.