Information on heterosis and inbreeding depression for yield and agronomic characters is essential for sunflower （Helianthus annuus L.） breeding programs. This research was conducted to evaluate heterosis and inbree...Information on heterosis and inbreeding depression for yield and agronomic characters is essential for sunflower （Helianthus annuus L.） breeding programs. This research was conducted to evaluate heterosis and inbreeding depression for yield and agronomic characters of hybrids involving eight sunflower inbred lines. These inbred lines were crossed in 8×8 half diallel to obtain 28 F The 28 hybrids were self-pollinated to produce the F2 generation. The 8 parents, 28 F1 hybrids and 28 F2 populations hybrids were evaluated using a randomized complete block design with three replications at two locations in Nakhon Ratchasima （SUT Farm and National Corn and Sorghum Research Center） in 2009. Mid-parent heterosis and inbreeding depression were estimated for yield, head diamete oil content, 1,000-seed weight and plant height. Significant differences were found among the parents, F1 hybrids and F2 populations for all traits. F1 hybrid means were significantly higher than the parental means for all traits. In addition, F1 hybrids considerable heterosis and heterobeltiosis when compared with the mid-parent and better parents, respectively. Yield, showed oil content and plant height showed highly positive heterosis in F1 hybrids, ranging from 14.48 to 49.45%, 8.88 to 33.22% and 9.51 to 29 respectively. Similarly, heterobeltiosis were positive significant for yield （19.22 to 49.04%）, oil content （8.65 to 28.30%） and height （2,83 to 27.61%）. However, 1,000-seed weight showed a low level of heterosis in F1 hybrids （-9.36 to 8,07%） oil content, 1,000-seed weight and plant height in F2 populations were lower than their respective Fi hybrids the F2 populations was comparatively high for yield, oil content and plant height. The cross of lines 5A×for yield （49.45%） and 1,000 seed-weight （8.07%） but low 25%, plant Means for yield, Inbreeding depression in 2A gave the highest heterosis inbreeding depression for yield （10.06%）. Based on the mean performance and heterotic effects for seed yield, 1,000-seed weight and oil content, the inbred lines 2A and 5A are suggested for the development o hybrids,展开更多
文摘Information on heterosis and inbreeding depression for yield and agronomic characters is essential for sunflower （Helianthus annuus L.） breeding programs. This research was conducted to evaluate heterosis and inbreeding depression for yield and agronomic characters of hybrids involving eight sunflower inbred lines. These inbred lines were crossed in 8×8 half diallel to obtain 28 F The 28 hybrids were self-pollinated to produce the F2 generation. The 8 parents, 28 F1 hybrids and 28 F2 populations hybrids were evaluated using a randomized complete block design with three replications at two locations in Nakhon Ratchasima （SUT Farm and National Corn and Sorghum Research Center） in 2009. Mid-parent heterosis and inbreeding depression were estimated for yield, head diamete oil content, 1,000-seed weight and plant height. Significant differences were found among the parents, F1 hybrids and F2 populations for all traits. F1 hybrid means were significantly higher than the parental means for all traits. In addition, F1 hybrids considerable heterosis and heterobeltiosis when compared with the mid-parent and better parents, respectively. Yield, showed oil content and plant height showed highly positive heterosis in F1 hybrids, ranging from 14.48 to 49.45%, 8.88 to 33.22% and 9.51 to 29 respectively. Similarly, heterobeltiosis were positive significant for yield （19.22 to 49.04%）, oil content （8.65 to 28.30%） and height （2,83 to 27.61%）. However, 1,000-seed weight showed a low level of heterosis in F1 hybrids （-9.36 to 8,07%） oil content, 1,000-seed weight and plant height in F2 populations were lower than their respective Fi hybrids the F2 populations was comparatively high for yield, oil content and plant height. The cross of lines 5A×for yield （49.45%） and 1,000 seed-weight （8.07%） but low 25%, plant Means for yield, Inbreeding depression in 2A gave the highest heterosis inbreeding depression for yield （10.06%）. Based on the mean performance and heterotic effects for seed yield, 1,000-seed weight and oil content, the inbred lines 2A and 5A are suggested for the development o hybrids,
