Paper Title
Varietal Characterization of Aromatic Rice (Oryza sativa L.) Genotypes Under Rain-Out Shelter Condition

Abstract
Significant variations on characteristics were observed on different aromatic rice genotypes in their responses to drought stress imposed at different growth stages. Genotypes which exhibited significantly longer plumule length are Milagrosa, Peneliza (G), Pandan, CLSH1-C, Pirurutong (G), Suphanburi (3). With significantly long seminal root length eight days after seeding were genotypes such as Laila and H2OS2. With respect to number of leaves at vegetative stage genotypes Peneliza and CL-1 (Basmati 370) had significantly highest number of leaves. Genotypes with expressions of longer plumule length, longer roots and more leaves indicate their endurance to drought stress at vegetative stage. When drought stress was imposed during the reproductive stage genotypes Capaocan, Dipaocan, Peneliza and H20S1 manifested taller plant height and well exserted panicle when are indicative of their ability to withstand drought stress. Also Pirurutong (G), and Suphanburi 1 produced highest number of productive tillers suggesting that they can resist drought; while Peneliza, Suphanburi 60, Suphanburi 1, and Capaocan had significantly the long root length at maturity and genotypes that had heavy root weight at maturity were CL-1 (Basmati 370), Basmati 385 and CLSH1-C. Dipaocan, Basmati 385, CL-2 (Kasturi) and Capaocan exhibited significantly long panicle length while Capaocan, Dipaocan, Suphanburi 3, Peneliza, Jasmine, Suphanburi 1 and Suphanburi 60 showed significantly more number of primary branches per panicle; Dipaocan, Suphanburi 1, Suphanburi 3 and CLSH1-A had significantly high percent filled grains; Jasmine had heaviest weight of 1000 grains; Ginesking, Dipaocan, Peneliza and Porac 1 had significantly high yield. Varieties which responded desirable characteristics even under stress are indications of their potential materials for further improvement in developing tolerance for drought environment. Genetic variability of grain yield and yield contributing characters, had high estimate of genotypic coefficient of variation which means that they are influenced by genetic factors. On the other hand, root weight at maturity had high phenotypic coefficient of variation which shows that this trait is more influenced by environmental factors than genetic factors. Correlation coefficient analysis indicated that there is strong positive and significant correlation of yield with percent filled grains (r = 0.421**), panicle length at maturity (r = 0.491**), and weight of 1000 seeds (r = 0.387**). Index Terms� Genotypes, Genotypic Coefficient of Variation, Panicle Exsertion, Phenotypic Coefficient of Variation, Rain-Out Shelter.