Agro-physiological and Genetic Characterization of Three Quinoa (Chenopodium quinoa Wild.) Cultivars to Drought Stress

The present investigation aimed to study the impact of water stress on three quinoa cultivars namely; quinoa 1, rainbow and American cultivar. Where, the three quinoa cultivars rated as various reactions for water deficit tolerance and were evaluated under the control and water stress conditions during two growing seasons. Some agro-morphological and physiological traits associated with water stress tolerance were measured under both conditions during the two seasons. Also, heritability in broad sense, PCV %, GCV %, D Z , GA and GAM % were the most important genetic parameters calculated for all studied traits under the same conditions during the two growing seasons. Water deficit tolerance indices were a fruitful and fertile test used to determine the various tolerance degrees of drought stress in the three quinoa cultivars for the traits; number of branches/plant, number of leaves/plant, 1000-seeds weight and seed yield/plant in both years. Five polymorphic protein bands out of six produced (83.3%) of polymorphism which indicated the genetic variations of three quinoa cultivars under water stress. The three quinoa cultivars were able to prove that they are varied tolerant to water stress, depending on the results of all studied traits, especially yield and its components, root and physiological traits namely; proline, glycine betaine and trehalose contents. Where, the cultivar quinoa 1 was coming at the first place as a tolerant, followed by rainbow and then followed by the American cultivar as a moderate to sensitive. In any case, the three quinoa cultivars recorded a good and satisfactory yield under water stress conditions compared to the standard experiment in parallel of the results of roots and physiological attributes represented in proline, glycine betaine and trehalose contents production which were excellent under stress compared to the control conditions. Using SCoT primers, there were high genetic diversity and generated 131 fragments where 89 of them were monomorphic besides, 42 polymorphic bands with 32.06 % polymorphism. In addition, detected 42 specific markers (17 positive and 25 negative) as genetic markers used at the molecular level to identify quinoa cultivars that are tolerant to water stress over those that are moderately to sensitive. Changes in isoenzymic were studied using PAGE under nonreduced, non-denatured conditions at 4 _C. Native PAGE analysis was performed for various enzymes involved in the ascorbate–glutathione cycle on a gel (10%) with protein load of 50 lg in each well. Specific procedures for running and staining of gels for different enzymes are given below. Staining of gels SOD activity. Gels were soaked NBT solution potassium