Hassan Ebrahimi rad; hossin babazadeh; ebrahim amiri; hossin sedghi
Abstract
It is necessary to optimize productivity and usage of available water resources due to shortage of these resources and low irrigation efficiency in rice fields. In order to study the effect of different irrigation managements and planting densities on rice, cv. Hashemi, an experiment was conducted in ...
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It is necessary to optimize productivity and usage of available water resources due to shortage of these resources and low irrigation efficiency in rice fields. In order to study the effect of different irrigation managements and planting densities on rice, cv. Hashemi, an experiment was conducted in a randomized complete block design (RCBD) with three replications at Koshal-Lahijan, in north of Iran, during cropping seasons of 2014 and 2015. There were 5 levels of irrigation treatments in this research including: I1 = Submerged irrigation, I2 = Saturation, I3 = Irrigation with 8 days interval before anthesis, I4 = Irrigation with 8 days interval after anthesis, I5= Irrigation with 8 days interval throughout the growing season). Also, there were 3 levels of planting density including, D1=15×15, D2=20×20, and D3=25×25 cm. Combined variance analysis showed that the effect of water stress and plant density on measured traits were significantly different (p<0.01). I1 had the highest yield in all treatments during the growth season, which was equal to 4151kg. Yields of I2, I3, I4, and I5 were equal to 4054, 3949, 3244, and 2787, respectively. Water productivity values of I3 and I5 were equal to 1.90 and 1.45 kg.m-3, which were the maximum and minimum (irrigation + rain) water productivity based on biomass. The results also showed that irrigation with 8 days interval before anthesis decreased water use by 16%, but it caused only 4% yield reduction. Analyzing different crop densities showed that yield components increased in high density (D1), while yield per unit area and water productivity decreased when plant densities decreased (D3). So, (D2) is the optimum spacing and is recommended.
h e; a a
Abstract
This research was carried out to evaluate the effect of drought on germination, growth, and fruit yield of okra in laboratory and field. Laboratory experiment was conducted as a two-factor factorial in agricultural laboratory of Khuzestan Payame Noor University based on completely randomized design in ...
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This research was carried out to evaluate the effect of drought on germination, growth, and fruit yield of okra in laboratory and field. Laboratory experiment was conducted as a two-factor factorial in agricultural laboratory of Khuzestan Payame Noor University based on completely randomized design in three replications. The first factor was seed priming (including control and seed priming with water and KNO3) and the second factor was drought stress (matric potentials of -0.3, -0.6, -0.9 and -1.2 MPa). Results indicated that the highest germination percentage was observed under no-stress and hydro priming conditions. Seed germination was decreased with increase in stress, where in control treatment i.e. without hydro priming, increasing drought stress from the first to third level resulted in 72.3 percent reduction in germination percentage. Hydro priming improved seed germination under drought stress and no-stress conditions. The field experiment was carried out during 2015-16 growing season based on RCBD in three replications. The irrigation intervals treatment was based on 70, 100, 130 and 160 mm evaporation from pan. İncreasing irrigation intervals reduced dry matter accumulation, leaf area index, plant height, friut number per plant, and biological and fruit yield of okra. Increasing irrigation interval from the firt level to the second, third, and fourth levels decreased fruit yield up to 9%, 26%, and 31 percent, respectively. Therefore, for optimum yied, okra should experience no drought stress during growth and friut formation. Thus, irrigation after 70 mm evaporation from evaporation pan can be advisable as an irrigation interval for okra. However, since friut yield reduction in the second level of irrigation interval was not considerable and considering economic issues, it may be possible to suggest this irrigation inerval, but it requires more research work.
hamed zamani; d a; h m; f a
Abstract
In order to investigate the effects of different irrigation regimes on yield quantity and quality of flue-cured tobacco cv. K326, an experiment was carried out based on a randomized complete blocks design (RCBD) with three replications, at Tirtash Tobacco Research Center, in 2011. Treatments were combination ...
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In order to investigate the effects of different irrigation regimes on yield quantity and quality of flue-cured tobacco cv. K326, an experiment was carried out based on a randomized complete blocks design (RCBD) with three replications, at Tirtash Tobacco Research Center, in 2011. Treatments were combination of W1= 40%, W2=60%, W3=80%, and W4=100 percent crop water requirement with D1=5, D2=10, D3=15 days irrigation interval with two control treatments (without irrigation (R) and furrow irrigation (I)). The results showed that treatment W4D1, W4D2, W4D3, W3D1, W3D2, W3D3, W2D1, and W1D1 had statistically significant difference with the other treatments and had more dry leaf yield. Also, the minimum leaf chlorine content was observedin W4D2, W3D1, W2D1, W2D2, W1D3, and Rtreatments. Under W4D2, W3D1, W3D3, W2D1, W1D1, W1D2, and W1D3 treatments, tobacco had statistically significant difference with other treatments and had higherprice. Also, the minimum gross income was obtained under W2D2, W2D3, W1D3, I, and R Treatments.
H B; A A; A KH
Abstract
In order to investigate the effect of irrigation and straw mulch on yield andyield components of bean, a split-plots experiment with randomizedcomplete block design in three replications was conducted in AstanehAshrafiyeh city during 2012. In this study, irrigation managementtreatments including ...
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In order to investigate the effect of irrigation and straw mulch on yield andyield components of bean, a split-plots experiment with randomizedcomplete block design in three replications was conducted in AstanehAshrafiyeh city during 2012. In this study, irrigation managementtreatments including no irrigation, irrigation frequencies of 6, 12, and18days, and different amounts of straw mulch as 0, 1, 2, and 3 cm thicknesswere examined. The results of the analysis of variance revealed thatirrigation management and different levels of mulch had significant effectson seed yield. But, their interaction was not significant on seed yield. Thetrend of variations indicated that the highest seed yield with 2431.3 kg ha-1was associated with irrigation frequency of 6 days. [n response to the maineffects of mulch levels, the highest average seed yield (1585.6 and 1518.4kg ha-1) was obtained in the 2 and 1 cm treatments, respectively. Also,using straw mulch in irrigation conditions prevented severe seed loss incomparison with no mulch condition. The highest water use efficiencywas in irrigation frequency of 18 days with an average of 0.58 kg m-3.Water use efficiency at straw mulch levels of 1 and 2 cm was observed as0.63 and 0.6 kg m-3, respectively.
Hamed Hasanzadeh; Abdolhossin Mohammadi; Ebrahim Zakerifard; Maryam Mohammadi
Abstract
In order to evaluate the effect of different irrigation regimes on yield and yield components of 4 onion cultivars in a warm and humid climate, an experiment was performed as split plot design in RCBD with 4 replications. Main plots consisted of 4 irrigation regimes (irrigation after I1=35±3, ...
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In order to evaluate the effect of different irrigation regimes on yield and yield components of 4 onion cultivars in a warm and humid climate, an experiment was performed as split plot design in RCBD with 4 replications. Main plots consisted of 4 irrigation regimes (irrigation after I1=35±3, I2=50±3, I3=65±3 and I4=80±3, mm evaporation from class A pan) and sub-plots consisted of 4 onion cultivars (‘White Grano’, ‘Admiral’, ‘Primavera’ and ‘Mineroa’). Seeds were sown in nursery and, after 2 months, transplants were planted in the field at 10×30 cm spacing. After bulb growth stopped and onion neck dried up, leaf number, plant height, bulb length, number of layers, dry matter, yield, and water use efficiency (WUE) were measured. Results showed that there was no significant difference between irrigation treatments in bulb length, layers number and dry mater. However, yield decreased by irrigation intervals up to 65 mm evaporation from class A pan, but it increased significantly in irrigation interval of 80 mm evaporation. Vegetative growth increased by reduction of irrigation interval. The highest WUE was observed in ‘Withe Grano’ and ‘Primavera’ cultivars in 80 mm evaporation treatment (5.528 and 5.381 kg/m3) and the least was in ‘Primavera’ cultivar in 35 mm evaporation treatment (1.858 kg/m3). WUE increased by reduction of irrigation in all cultivars. For ‘White Grano’, ‘Admiral’ and ‘Primavera’ cultivars recommended irrigation intervals is 19 days in January, 20 days in February , 15 days in March, and 12 days in April, based on 80 mm evaporation treatment. In the case of ‘Mineroa’ cultivar, considering no significant difference between the highest irrigation treatments with 65 mm evaporation treatment, it is recommended that irrigation intervals be 15 days in January, 17 days in February , 12 days in March, and 10 days in April. Under the condition of this study, White Grano cultivar, followed by Admiral, performed higher than the other cultivars, especially with respect to WUE and yield. Therefore, they are recommended for planting in the region.