Showing 6 results for Javanshir
Gh. Khajouei Nejad, H. Kazemi, H. Alyari, A. Javanshir, M. J. Arvin,
Volume 9, Issue 4 (winter 2006)
Abstract
This study was conducted to evaluate the effects of four levels of irrigation (irrigation of plants after I1 = 40, I2 =60, I3 = 80 , and I4 = 100mm of evaporation from class A pan) and four plant densities(D1 = 30, D2 = 40, D3 = 50 and D4 = 60 plants/m2) on the seed yield and seed quality in three soybean cultivars(V1=Hobit, V2=Williams and V3=Hill) in a split factorial design, based on the completely randomized blocks, with three replication for two years(2001 and 2002). The Irrigation treatments were assigned to the main plots, and the plant densities and cultivars to the sub plots. Results indicated that soybean seed yield was influenced by the different irrigation and plant density levels in the both years. Irrigation levels I2 produced the highest and I4 the lowest seed yield. It was also revealed that the plant density D3 produced the highest and D1 the lowest seed yields. Among the cultivars under investigation, V2 produced the highest and V3 the lowest seed yield . Seed oil and its protein contents both were affected significantly by the irrigation levels, plant densities and cultivars in both years. The plants receiving I1 treatment had the highest and those having I4, the lowest percentages of seed oil. Changes in the plant densities also affected seed oil and protein content. The plant density of D1 caused the seeds to have the highest oil and lowest protein percentages. However, D4 decreased oil and increased protein percentages. The highest water use efficiency was obtained from I3 and that of the lowest value from I1. The results also indicated that D4 had the highest and D1 the lowest water use efficiencies. Therefore, it could be concluded that the water use efficiency can be increased by increasing the plant density per unit area. The highest efficiency for biological and grain yield belonged to V2 and V1 respectively where as the lowest efficiency for those two mentioned characters belonged to V1 and V3, respectively. However, the treatment I2V2D2 is recommended for higer the seed yield production per unit area.
Gh. Mohammadi, K. Ghasemi Golezani, A. Javanshir, M. Moghaddam,
Volume 10, Issue 2 (summer 2006)
Abstract
In order to investigate the effect of different irrigation regimes on some agronomic and physiological characters of three chickpea cultivars (Jam, 301 and Pirooz), a field experiment was conducted in 1998 at the Agricultural Research Farm of Tabriz University, Tabriz, Iran. A split plot experiment based on a randomized complete block design with three replications was used, in which irrigation treatments (full irrigation, irrigation at only branching or flowering and or pod formation stage) were in the main plots and chickpea cultivars were in the sub plots. Under limited irrigation conditions there were no significant differences among irrigation regimes for green cover percentage and the number of pods per plant while rate and duration of grain filling, grain weight and grain yield were significantly higher for irrigation at pod formation than for irrigation at branching or flowering stage. The mean of all the traits, except for the number of seeds per pod were significantly higher for full irrigation than for limited irrigation treatments. Rate of grain filling, maximum grain weight and grain yield were significantly higher for irrigation at flowering than for irrigation at branching stage. While, other characters were not significantly different between these two treatments. Although, green cover percentage and seeds per pod in 301 were higher than those in Jam, but in other cases their response to water limitation was almost similar. All traits, except the number pods per plant, were noticeably lower for Pirooz compared to Jam and 301 cultivars. Green cover percentage showed the highest correlation with the grain yield. This study revealed that among phenological stages of chickpea, pod formation is the most sensitive to water deficit, and that under water limitation conditions chickpea yield could be improved by irrigation at this stage.
Y. Raei, K. Ghasemi Golezani, A. Javanshir, H. Aliari, A. Mohammadi,
Volume 12, Issue 45 (fall 2008)
Abstract
Concerning the effects of increasing the species number on the maintenance of ecological stability and agricultural ecosystems sustainability, two field studies were conducted in 2002 and 2003 to evaluate the effects of plant population densities on soybean and sorghum intercropping at the Research Center, the Faculty of Agriculture, Tabriz University, Tabriz, Iran. Cultural pattern was an additive series. The factorial set of treatments was arranged within a randomized complete block design with three replications. The first factor comprised soybean densities of 20, 30, 40, and 50 plants/m2, and the second factor consisted of sorghum densities of 0, 4, 8, and 12 plants/m2. The results indicated that both soybean and sorghum yields were significantly affected by soybean and sorghum densities. Soybean yield increased as density increased up to 40 plants/m2, and then decreased with increasing soybean density from 40 to 50 plants/m2. With increasing soybean density, sorghum yield was decreased. Sorghum and soybean yields, respectively, increased and decreased as sorghum density increased. On the other hand, Soybean and sorghum densities of 20:4 (1.6) and 50:12 (0.8) had the highest and the lowest LER (Land Equivalent Ratio), respectively. It was, therefore, concluded that intercropping of Soybean and sorghum, is more advantageous, compared to their pure cultivation in the same conditions.
F. Sorkhy Lalelo, A. Dabbagh Mohammadi Nassab, A. Javanshir,
Volume 12, Issue 45 (fall 2008)
Abstract
A pot experiment was designed to investigate the effects of full, above and below ground interactions of wheat with wild oat on leaf characteristics and root to shoot ratio. This experiment was conducted as a factorial based on randomized complete design with four replications. The treatments included four interference levels (above ground, below ground, above and below ground and check wheat and wild oat) and four wild oat densities (2, 4, 6 and 8 plants/pot).The effects of full and root interference on wheat and wild oat traits was greater than shoot interference. For both species, full and below ground interaction significantly decreased the number of leaves, flag leaf area and chlorophyll content of flag leaf compared to above ground interaction and control. All traits of wild oat were reduced by above ground interaction compared to control. Number of leaves of wheat and wild oat showed greatest susceptibility to interaction treatments. There was no significant different between full and root interference. When wild oat density increased, the number of leaves, flag leaf area and chlorophyll content of flag leaf of wheat decreased. With strongest competition followed by enhanced wild oat density, root to shoot ratio in wheat and wild oat increased, which indicates more susceptibility of shoot than root to interference mean competition. This ratio for wild oat was more than wheat, thus, it is concluded that wild oat has higher rooting ability compared to wheat.
F. Heidari, S. Zehtab-Salmasi, A. Javanshir, H. Aliari, M. R. Dadpour,
Volume 12, Issue 45 (fall 2008)
Abstract
In order to examine the effects of plant density on the morohological traits, yield and essential oil of peppermint, an experiment was conduced in Agricultural College of Tabriz University during 2005 and 2006. The treatments included four plant density levels ( 8,12 ,16,20 plants.m-2) with three replications. The treatments were based on a split plot design in time and result analysis of compound variance was done during two years. The two years’ results of the compound variance showed that the plant density affected the fresh yield, dry yield, the bush essential oil percentage and the essential oil yield, but it had no effect on the bush height and the leaf’s essential oil percentage. In the second year, the maximum fresh yield, dry yield, bush height, the bush essential oil percentage, and the essential oil yield were obtained. In the second year, the maximum essential oil yield in the density of 20 plant/m2 was 21.15 li.ha-1.
R S.sharifi, A Javanshir, M Shakiba, K Ghasemi Golezani, A Mohamadi, Y Raei,
Volume 12, Issue 46 (fall 2009)
Abstract
In order to study yield component and determinate the contribution of stem reserves to corn yield under effect of different densities and interference periods of sorghum, a factorial experiment based on randomized complete block design with three replications was conducted in 2002 on the Research Farm of the Faculty of Agriculture Tabriz University. Experimental factors were sorghum interference at different periods (0,14,28,42 days after corn emergence and also during plant life corn) with three densities (4,8,12 plants m-2). Characteristics of study were yield, yield component and the contribution of stem reserves to corn grain yield. The results showed that with increasing sorghum density and interference, corn yield components (except the number of grain rows) were decreased, due to shading and competition between plants for using available resources. Maximum grain yield and grain number per ear was obtained at pure corn plantation. With increasing sorghum density and interference periods grain yield decreased, and maximum corn yield loss was 38%, which occurred at the highest sorghum density and interference. Dry matter remobilization and contribution of stem reserves were significantly influenced by sorghum densities and interferences in corn grain yield. The highest contribution of dry matter remobilization and stem reserves to corn yield was obtained at maximum density and complete interference of sorghum. The least contribution of reserves was shown in pure corn plantation. This might be related to shading and competition between plants for light and other resources.
