In this study, we assessed the extent of genotypic differences among rice genotypes for grain size, milling quality, cooking properties, protein, and the mineral contents of Fe, Zn, Mn, and Cu in unpolished rice varieties. Further, relationship among grain quality traits and mineral contents was determined. The results showed that the visible difference could be found in the mineral contents among rice genotypes studied. The contents of Fe and Zn in traditional genotypes were significantly higher than those of improved cultivars. There was a negative correlation between grain yield and mineral contents. However, Fe, Zn, Mn, and Cu contents appeared to be positively correlated. The relationships between mineral element contents and cooking quality traits viz., kernel length after cooking and kernel linear elongation ratio were positively correlated, indicated the role of micronutrients in cooking quality traits. Both Fe and Cu contents were correlated positively and significantly with head rice recovery. The eigen values of 1st 6 principal components (PC) were > 1.0. The present study suggests that breeding for high minerals will be probably realistic.

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Rice plants are damaged during floods by complete or partial submergence. The pattern of expression of rice plant varies with different flood regimes. Accordingly, the morphological and physiological responses of rice genotypes were studied in field and pot experiments under different flood regimes. Wide genetic base lines of Oryza sativa and sub 1 introgressed submergence tolerant were compared in field experiments using principle component analysis. Further, based on internode elongation pattern, two genotypes – Bodikaburi and Pokkali – were selected for a pot experiment to find more on elongation pattern of internodes under different flood regimes. Short-term submergence in minimal water, elongation of blade, sheath, leaf area, DW, number of nodes in primary stem and survival present showed strong positive relationship with shoot length. Number of tillers, leaf area and DW were more affected and decreased during submergence than its non-submergence counterpart. Under different flooding regimes, cvv Bodikaburi and Pokkali exhibited different behaviour in the elongation pattern of the shoot. Partial submergence accelerated elongation of all internodes whereas complete submergence accelerated the top internode. Enhancement of shoot elongation during submergence in water is an escape strategy adopted by rice to resume aerobic metabolism and to improve carbon fixation. This escape strategy varies among genotypes with respect to different flooding regimes. Therefore, breeders should be aware of breeding of rice plants with suitable architecture for different flood- prone environments.

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Thirty nerium accessions were evaluated for growth and flower yield. Each accession had specific vegetative and flowering traits, among them ACC-19 (Rasipuram pink double) recorded the maximum plant height (236.84 cm) and flower yield per plant (333.09g). ACC-2 (Panamarathanpatty white single) recorded the maximum number of primary branches (6.80). Leaf area (33.61 cm2), early flower bud initiation (90.47), flower bud length (3.40), number of inflorescences per plant (24.17), number of flowers per plant (10.67) were maximum in ACC-12. Accessions 12 (Rasipuram pink single) displayed profuse blooming and long-lasting blooming characteristics, which made them an excellent choice for commercial cultivation and landscaping.

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