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Improvement of eating and cooking quality is one of the main objectives in rice breeding programs in Iran. In this study various rice genotypes, including upland, aerobic rice, Iranian improved varieties and landraces known for grain quality, were studied for eating, cooking, physicochemical characteristics as well as molecular evaluation with SSR molecular marker and three genes based markers (GBSSI (Wx), GW8/OsSPL1 and AGPase-S), at the University of Guilan, Rasht, Iran across two years: 2015 and 2017. According to the results, the best quality and aromatic varieties showed moderate values for amylose content (AC) and gelatinization temperature (GT) 21.06 and 4.27%, respectively and also moderate trough viscosity (TV) 149.06, final viscosity (FV) 276.77 and setback viscosity (SBV) 67.05. Association analysis revealed that SSR marker, RM589 was associated significantly with AC, peak viscosity (PV), SBV and consistency viscosity (COV). SSR marker, RM190 was also found as the common SSR marker associated with peak viscosity (PV), TV, and FV and RM3498 was correlated with GT, SBV and COV in both the years. On the other hand, haplotype analysis with reference to Domsiah as a famous aromatic variety revealed the best quality Iranian rice varieties such as Hashemi, Hasansaraei and Sadri had the Domsiah alleles for RM276, RM190, and RM3498 markers. The results suggest that the identified informative markers have a strong association with rice grain quality and could be utilized in subsequent studies and marker-assisted breeding aiming to improve grain quality. [ABSTRACT FROM AUTHOR]

Rice is staple food in Iran. Despite of high quality of local rice, their grain yield is low. In hybridization breeding programs, selection of suitable parents is an essential role for developing new combinations with broadens genetic diversity. Combining ability of local rice varieties namely 'Hashemi', 'Sang Jo' and 'Tarom Deylamani' and 'Nemat' was evaluated in a partial diallele analysis for agronomic traits in a randomized complete block design at Sari Agricultural Sciences and Natural Resources University. General combining ability (GCA) and specific combining ability (SCA) variances showed predominated role of additive gene effects in the inheritance of grain length. Both additive and non-additive components of genetic variances were important in the inheritance of traits like grain yield, plant height, panicle length, total grains per panicle, grain length and grain length to width. However, non-additive gene effects were seen for tiller number. Results showed that 'Nemat' was the best general combiner for most of characters followed by 'Tarom Deylamani'. The cross of 'Hashemi' × 'Tarom Deylamani' was suggested to exploitation of heterosis breeding for increasing yield and its components in rice breeding programs [ABSTRACT FROM AUTHOR]