kaveh limouchi; Mehrada Yarnia; Ataollah Siadat; Varharam rashidi; Abdolali Gilani
Abstract
This study aimed at establishing the effect of different irrigation intervals on current assimilation and yield of rice genotypes. This research was conducted in Khuzestan Province for two years (2014 and 2015) using four irrigation intervals (1, 3, 5, and 7 days) in the main plots and 12 rice genotypes ...
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This study aimed at establishing the effect of different irrigation intervals on current assimilation and yield of rice genotypes. This research was conducted in Khuzestan Province for two years (2014 and 2015) using four irrigation intervals (1, 3, 5, and 7 days) in the main plots and 12 rice genotypes in the sub-plots, with three replications. The combined analysis results showed that the main levels of irrigation interval, genotypes, and their interaction effect had a significant (P< .01) effect on all attributes. The amount and contribution of current assimilation of the three-day interval with an average yield of 4586.9 kg per hectare and 89.3 percent share had the highest relative value. Moreover, considering the highly positive correlation of grain yield with amount and contribution of current assimilation that were, respectively, (R=0.9**) and (R= 0.5**), we could conclude that the main reason for the increase in rice grain yield in this irrigation treatment was due to the increase in current assimilation – related attributes and allocation of more photosynthesis products to the main plant source. Consequently, IR 81025-B-327-3 genotype in the 3-day interval, which had the highest current assimilation, had relatively high share and efficiency of current assimilation and the highest grain yield with the average of 6555.1 kg per hectare. In general, the increased yield of rice genotypes with greater resistance to drought, especially regarding the three-day interval, can be attributed to the ability of leaf source to increase the considered attributes and the high volume of the tank in fully receiving the assimilated matter produced by processes connected to attributes associated with these properties.
N A; A R
Abstract
In order to investigate the effect of salinity on morphological, physiological and biochemical characteristics of Lisianthus, a pot experiment was conducted hydroponically in sand. Two Lisianthus varieties (‘Champagne’ and ‘Pure White’) and four NaCl concentrations (0, 20, 40, ...
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In order to investigate the effect of salinity on morphological, physiological and biochemical characteristics of Lisianthus, a pot experiment was conducted hydroponically in sand. Two Lisianthus varieties (‘Champagne’ and ‘Pure White’) and four NaCl concentrations (0, 20, 40, 60 mM) were combined factorially based on a complete randomized design with four replications. The result showed that as salinity increased plant height and fresh and dry weights decreased. Also, chlorophyll a content, photosynthesis rate, and relative water content of plants treated with 60 mM NaCl were, respectively, 31%, 62%, and 20%, lower than the controls. In addition, root length increased with increasing salinity, so that in plants treated with 60 mM NaCl root length was 43% larger than the controls. Further, electrolyte leakage and Malondialdehyde (MDA) content increased with increasing salinity. Results revealed that dry weight, plant height, and photosynthesis rate in ‘Pure White’ were, respectively, 47%, 27%, and 31% higher than in ‘Champagne’. Moreover, under salinity stress, ‘Pure White’ could maintain better morphological and physiological characteristics, i.e. plant height, dry weight, relative water content and cell wall stability compared with ‘Champagne’.