Showing 4 results for S. A. M. Mirmohammady Maibody
S. A. M. Mirmohammady Maibody, A. Amini, J. Khajeddin,
Volume 7, Issue 2 (summer 2003)
Abstract
In this study, the potential use of halophyte grasses, Aleuropus littoralis and A. lagopoides, on soil desalinization and lowering soil salinity was investigated under glasshouse conditions. The seeds of two species were collected from Rodasht area in Isfahan and grown with four salinity treatments obtained from different types of collected soils and replicated three times. Electrical conductivities of the four soil treatments were 12.4, 29.5, 43, and 69 dS/m. The results of mean comparison showed that shoot and root dry weight, sodium contents of dry weight and Na/K ratio were significantly different in both salinized species. Both species effectively reduced soil electrical conductivity by 23 to 42.5%. This was mainly due to ion absorbtion, and consequently, from Na+, Cl-, Mg2+, Ca2+ ionic reduction. In general, considerable amounts of ionic absorbtion and total soluble salt secretion through their salt glands appeared to have the most pronounced effects on decreasing soil salinity. Regarding 50% salt excretion by these species, growing these grasses could be a possible way to decrease soil salinity by grazing or harvesting salt crusted foliage from the site.
H. Sabori, A. Rezai, S. A. M. Mirmohammady Maibody, M. Esfahani,
Volume 9, Issue 1 (spring 2005)
Abstract
An experiment was conducted at Rasht Rice Research Institute, in 2001 to study trait relationships and to determine the direct and indirect effects of different characteristics on grain yield of rice (Orgza sativa L.). A 9x2 factorial experiment in complete randomized block design with 3 replications was used. The two factors were 9 cultivars, namely: Hashemi, Ali Kazemi, Binam, Sepeedroud, Nemat, Khazar, Taichung, Chanto, and Usen, and 2 planting patterns (15x15 cm and 30x30 cm). Significant differences were detected among cultivars, between planting patterns, and their interaction effects. The direct effect of the number of panicles/m2 on grain yield was positive and significant in both planting patterns and their combined analysis. Heading date had a positive and significant direct effect on the number of panicles/m2 in both planting patterns and their combined analysis. Only in 30x30 cm planting pattern, a positive correlation was found between biomass at heading date and the number of panicles/m2. Grain weight per plant had a direct and positive effect on panicle weight in the 3 cases studied. Also, in all the cases studied, flag leaf area had positive direct effects on grain weight per plant. Grain filling rate and effective grain filling period increased in 30x30 cm planting pattern. Native cultivars demonstrated longer latent period. Grain filling rate and effective grain filling period showed positive direct effects on grain yield in both plantings. According to the results obtained, an increase in the number of panicles/m2, rate of grain filling, and effective grain filling period would enhance grain yield. Selection for heading date, grain yield per plant, and flag leaf area would also indirectly increase grain yield.
B. M. Ashour, A. Arzani, A. Rezaei, S. A. M. Mirmohammady Maibody,
Volume 9, Issue 4 (winter 2006)
Abstract
The Genetic basis of grain yield and related characteristics were studied by a generation mean analysis in five crosses of winter wheat (Triticum aestivum L.). “Roshan”, “Mahdavi”, “Inia”, “Atila” and “Goscoyin” cultivars along with their F1, F2, BC1 and BC2 populations were evaluated by a split-plot design with crosses as the whole plot in a randomized complete block design with two replications and generations were applied as the subplots. Analysis of variance revealed significant differences among generations for studied characteristics including the grain yield per plant, the number of spikelet per plant, the number of spikelet per spike and grain weight per spike. For the majority of traits and crosses, F/DH1/2 was less than one, indicating that the sign and magnitude of gene actions were different. Estimates of broadsense and narrow sense heritabilities were low for the grain yield per plant compared with other traits, rating from 28.5% to 58.6% and 24% to 48,5% for the five crosses, respectively. Genetic components of generation means were calculated by fitting different models and choosing the best model indicated that the impact of additive, dominance and epistasis genetic components in controlling the traits depend on the cross and the trait under study.
M. Kabiri, S. A. M. Mirmohammady Maibody, A. Shakib, A. Rezaei,
Volume 9, Issue 4 (winter 2006)
Abstract
To obtain a suitable explant and efficient culture medium for plant regeneration in spinach, two cultivars of Melody and Karaj local seedlings were chosen. A hypocotyl and cotyledon segments as well as shoot tip explants were dissected from seedlings. The explants were then cultured on MS medium supplemented with IAA, GA3, NAA, and BAP and their response to this media was studied. A completely randomized design with different replicates was used to conduct the experiments. Callus was formed at the base of the hypocotyl explants on the medium containing 15 mg.l-1 IAA, and 3.4 mg.l-1 GA3. Calli capable of regeneration was obtained after subculturing on the medium containing 2 mg.l-1 IAA, and 3.4 mg.l-1 GA3 at the rate of 38 percent. The vitrified plantlets were abnormally glassy, and translucent which might have high water content. It was a physiological disorder which was overcome when an improved agar medium raising to 9 gl-1 was used. Callus has been obtained only from the hypocotyl explants, while regeneration has been obtained from shoot tip cultured on the medium containing 0.02 mgl-1 BAP at the rate of 80 percent.
