Stability and adaptability of quality promising rice lines

To determine adaptability and stability of rice advanced lines,8 promising genotypes were evaluated in a Randomized Complete Blocks Design (RCBD) with 4 replications in 3 locations ( Rasht. Roudsar and Talesh) and in 3 years ( 2001-2003). In this study, some quantitative and agronomical characters such as grain yield, panicle number, 100-grain wieght,plant height, panicle length, days to 50% flowering, amylose content, gelatinazation temperature, gel consistency and milling recovery were measured. The results of the simple variance analysis indicated that these cultivars had a significant difference at 1% level for all characters. But there was no different among genotypes for panicle length in Rasht and for milling recovery in Roudsar in first year. The results of combined analysis revealed that there is a significant difference among varieties for all traits at 1% level. The location effect was only significant for 100-grain weight and there was no significant difference for other characters in different locations. In the meantime, the genotype location and genotype location year interactions were significant at 1% level for some characters like grain yield, plant height, amylose content, gelatinazation temperature and milling percent. The results of the mean comparision using Duncan method indicated that, the lines No. 838, 837, 840 and 841 had highest yield with 5.944, 5.918, 5.876 and 5.854 t/ha in three locations in 3 years respectively. Stability analysis through Lin and Bins method (1991), showed that two promising rice lines No. 840 and 841 are the most stable lines, because, they had the lowest variation coeficient and mean square within each locations. These two lines are located in intermediate amylose group and they are like Iranian local rice varieties in this regard. Therefore, they can be released as new rice varieties for Guilan province.