Diversification of parental base and development of elite lines, populations, varieties and hybrids in sunflower

500 new cross combinations were made from 2009-2012 and evaluated for yield and SND tolerance at field level.100 new hybrids were synthesized using 20 CMS and 5 restorer lines. These hybrids were evaluated along with check during kharif 2009 to identify superior hybrids for seed yield and other agronomic characters. During rabi 2008-09, 100 new hybrids were synthesized using 20 CMS and 5 restorer lines. The best identified hybrids from 2008-09 and newly developed hybrids were evaluated together along with check during kharif 2010 to identify superior hybrids for seed yield and other agronomic characters. In F5 generation during 2012 four crosses were identified showing lesser than 25 % of disease incidence in in-vitro screening for SND tolerance where as Mordern had recorded 100 % susceptible reaction to SND. These two tolerant to SND prebred lines could be seen as potential tolerant lines for SND. Using seven CMS lines viz., CMS 234A, CMS 17A, CMS 852A, CMS 89A, ARM 238A, ARM 243A and ARM 248A and six inbred lines viz., RES-834-1, LTRR 341, RHA-6D-1R, 3376R, R-298 and R-649 crossing was performed in line\ x tester fashion to produce 42 hybrids. During rabi, 2009-10 the 42 hybrids along with their parents and three standard checks viz., KBSH-1, PAC-1091 and KBSH-44 were evaluated in a Randomized Block Design replicated thrice at three different locations viz., Directorate of Oilseeds Research, Hyderabad; Agricultural Research Station, Tandur; and Regional Agricultural Research Station, Jagtial. Observations were recorded on five randomly selected plants in each hybrid combination per replication for nine quantitative characters. Pool mean performance of parents and hybrids for different yield and yield components is presented in table 1. A total of 300 new crosses were synthesized during the year rabi 2011-12. 30 testers were used in the crossing programme against pet 2 derived 10 CMS lines