Evaluation of some rice (Oryza Sativa L.) genotypes under water stress conditions [electronic resource].

Includes references.

Laboratory experiment was conducted at Seed Technology Research Unit in Mansoura, Dakahlia Governorate, Field Crop Research Institute Agricultural research center to evaluate germination and seedling growth of fifty-one rice genotypes under water stress conditions induced by 20% of polyethylene glycol 6000. Also, Field experiments were carried out at Sakha Farm Station, Kafr El-Sheikh Governorate during 2009 and 2010 seasons to evaluate the same fifty-one rice genotypes under flashing water irrigation every 12 days. The results indicated that 20% of PEG solution inhibited all seedling characters in the most of rice genotypes. Giza 178, Sakha 104, Sakha 101, Sakha 102, Rb 10, IET 353, Bala, Cica 4 Giza 172, Giza 181, Bl 1, Mizuho, Yabani M 52, Suweon 351, Suweon 353, BG 367 and Co 39 were superior than IET 1444 (control) in root , shoot lengths and seedling weight. The aforementioned rice genotypes not more affected by PEG therefore, more resistance to water deficit. Also, the highest number of panicles/plant, 100-grain weight, grain yield/plant, the lowest values of panicle length and sterility % were resulted from Giza 178, Sakha 101, Sakha 102, Sakha 104, IET 353, Cica 4, Bala, Giza 181 and Co 39. Genotypic and phenotypic coefficients of variation (GCV and PCV) were found to be high for most of studied characters. Broad- sense heritability estimates ranged from moderate to high for all studied characters. High expected genetic advance was associated with high heritability. High heritability values coupled in number of filled grains/panicle, plant height, germination %, days to 50% heading and grain yield/plant. These characters showed to be highly heritable, points to the predominance of additive gene effect, easily fixable and can be taken as unit characters for effective selection. Also, high genetic advance with high heritability, lead to conclude that effectiveness of selection of most studied traits, might be practiced in the advanced generations. Grain yield/plant was strongly phenotypic positively correlated with germination %, root and shoot lengths, seedling vigor index and seedling weight. The results showed that the amount of added water to the genotypes studied ranged from 4012.63 to 4819.17 m3/fed. The m3 of water gave the highest of grain yield in Bala, Giza 178, Sakha 104, Sakha 101, Yamgdoeg, Giza 181, Sakha 102, Sakha 103, IET 353, TKY 104, Co 39, Bl 1, Yabani M55, GZ2447-5-7 and Cica 4 followed by IET 1444(780, 770, 760, 740, 710, 710, 700, 700, 690, 690, 680, 650, 630, 610, 580 and 580 g/m3, respectively). It could be concluded that rice genotypes under study is considered the best parents for drought recovery ability and could be considered as a donor in crossing with drought tolerance to cover the growing rice area which affected by water shortage in the terminal of irrigation canal.

Summary in Arabic.

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