Assessment of eating and cooking parameters, nutritional quality and molecular diversity in premium quality rice varieties using microsatellite markers
Rice is the staple food crop for more than 50% of the population worldwide. Grain yield and quality are the most important targets in rice breeding. In recent times, increase in living standards, and increased awareness among the peoples all over the world has resulted in an increase in the demand for better quality rice. Breeding for the improvement of quality and nutrient rich rice has become crucial. The focus is on traits such as milling properties, appearance, eating and cooking parameters (physico-chemical properties) and nutritional quality. However, preference for grain quality is highly variable in different regions, countries and among different consumers. In this investigation, we are evaluating the quality and nutritional parameters of major premium quality rice varieties popular in India. Here, we selected 20 rice varieties and evaluated them for fourteen grain quality parameters namely, hulling percentage, milling percentage, head rice recovery percentage, grain length, grain breadth, kernel length (KL), kernel breadth (KB), Length/Breadth ratio(LBR), kernel length and breadth after cooking, linear elongation ratio, amylose content, gel consistency and alkali spread value (in direct estimation for gelatinization temperature). All these quality parameters were phenotyped by the methods based on Standard Evaluation System of Rice including alkali spread value. The results reported significant differences among the quality traits studied and association analysis recorded these findings - KL is positively correlated with LBR, KL and AC ; kernel width/breadth was significantly positively correlated with KBAC ; and GC was highly associated with ASV. In the case of the micronutrients, Zn and Fe content are positively correlated. Diversity analysis was carried out using 40 Simple Sequence Repeats (SSR) markers associated with quality and nutritional traits, scoring based on presence (1) and absence (0). Dendrogram was constructed using Darwin software version 5.0 and resulted in three major clusters, in first cluster were present the popular varieties namely Swarna, Swarna Sub1, Samba Mahsuri and N22 whereas MTU1010, Lalat, Sahbhagi dhan, Rajendra Mahsuri and HMT were in the second cluster and the third cluster carried all the other genotypes.
Keywords: Rice, grain quality, Amylose and XRF.