Showing 2 results for Drought Stress.
J. Ahmadi, S.f.orang, A.a. Zali, B. Yazdi – Samadi, M. R. Ghannadha, A. R. Taleei,
Volume 11, Issue 1 (4-2007)
Abstract
Generation mean analysis (GMA) was used to study the type of gene action and inheritance of grain yield and its components. Generation mean analysis with joint scaling test was performed. This research was conducted at research farm of college of Agriculture at the University of Tehran. The parents and their progenies ( F1, F2, BC1 & BC2) in three mating groups ( Sardari × 7007, Sardari × 7107& 7107 × 5593) were produced and planted using a randomized complete block design with four replications for each mating group. Of four replications in each experiment, two replications for drought and two replications for non-drought condition were used. The eight traits which were evaluated included grain yield, plant height, plant weight, tiller number, spike length, grains per spikes and 100 grain weight. Most of the genetic parameters including mean (m), additive (d), dominant (h), additive × additive [i], additive × dominant [j], and dominant × dominant[l] effects were significant. However, all gene effects were not significant in all traits.The dominant gene effect was the most contributor factor to inheritance of the majority of traits. For the majority of the traits, additive gene effect was significant, but its magnitude was less than dominant gene effect. Also the dominant × dominant[l] epistasis was more important than additive× additive [i] epistasis. The degree of dominance in most of traits indicated the predominance of dominant gene effects.
A Masjedi, A Shokohfar, M Alavi Fazel,
Volume 12, Issue 46 (1-2009)
Abstract
The increasing cultivation of corn in Ahwaz and the direct relation between the increase of the summer corn yield and its perfect irrigation in sowing period all together have made the research regarding this crop necessary. Deciding over the suitable irrigation scheduling of corn (hybrid SC.704) in summer by utilization of class A evaporation pan is the focal point of this research. Accordingly, a project was conducted in the form of stadistical perfect accidendal block in four repetitions and four treatments in 1383 on Ahwaz Azad university research land situated in Choneibeh. The irrigation treatment had four levels of T1,T2,T3 and T4 in class A evaporation pan containing of four levels of 50,75,100 and 150 mm, carried out in split plot. The suitable irrigation period was chosen according to the best treatment performance and its components, and the total amount of water in the taking period defines the depth of irrigation. The soil texture is clay lomy silty and the internal soil is silty clay. According to the amount of the accumulated evaporation from class A evaporation pan and taking the plant coefficient (Kc) into consideration, the amount of needed evapotrans piration was calculated and the amount of needed water for plot was measured by water counter. Then a comparison between the means by the use of Donken multi domains test was made and in this way the superior treatment was selected. Accordingly, the most suitable time for irrigation of summer corn in Ahwaz was after 50 mm of accumulated evaporation from class A evaporation pan which equals ten irrigation in the growing period. So in order to acquire 12 tons of seed yield in each hectare, at least 9600 m^3 of water for every hectar is needed. However, given the equal amount of water, with 3 times decrease in irrigation in treatment T2 in comparison with T1, a performance near 11 tons and with five times decrease in irrigation and ten tons in treatment T3 a performance near 10 tons can be attained.
