Rasoul asadi; Frzad hasanpour; Mitra Mehrbani; amin baghizadeh; Fatemeh Karandish
Abstract
Using proper irrigation management leads to optimum utilization of water, soil, and fertilizer and production of high yield and quality products. In order to investigate the effect of irrigation intervals and surface and subsurface drip irrigation systems on growth indicators of Rosmarinus officinalis ...
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Using proper irrigation management leads to optimum utilization of water, soil, and fertilizer and production of high yield and quality products. In order to investigate the effect of irrigation intervals and surface and subsurface drip irrigation systems on growth indicators of Rosmarinus officinalis L., a field experiment was carried out during 2015 growing seasons at an experimental farm in Kerman city. The treatments were laid out in split plot using a Randomized Complete Block Design with three replications. The treatments comprised three irrigation levels (I 1 =25, I 2 =40 and I 3 =55 mm evaporation from class A pan) in the main plots, and two drip irrigation systems (surface and subsurface) in the sub plots. The results showed that I 2 in comparison with I 1 treatment led to 44 mm water saving. However, dry weight, height of plants, number of shoots per plant and leaf area index decreased by 12.9%, 12.6%, 13.6% and 5.3 percent, respectively, while water use efficiency increased 3.6 percent. Also, results showed that water use efficiency, dry weight, height of plants, number of shoots per plant, and leaf area index increased by, respectively, 15.1%, 18.3%, 9.7%, 12.5% and 15 percent in subsurface drip irrigation compared to surface method. Therefore, for Rosmarinus officinalis L. cultivation in Kerman area, application of I 2 in subsurface drip irrigation system is the best way to increase the water use efficiency for the drought years.
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.
m n; b gh; b b
Abstract
Aloe Vera (Aloe Vera L.) is a medicinal plant adaptable to arid and warm climates as well as water limited conditions and can be introduced in cropping pattern of southern region of Iran. A field experiment was carried out during two years (2010-2011) in Bushehr, Iran, to investigate the effects of irrigation ...
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Aloe Vera (Aloe Vera L.) is a medicinal plant adaptable to arid and warm climates as well as water limited conditions and can be introduced in cropping pattern of southern region of Iran. A field experiment was carried out during two years (2010-2011) in Bushehr, Iran, to investigate the effects of irrigation interval and amount of irrigation water on yield and water use efficiency (WUE) of Aloe Vera. The treatments were arranged in a split plot design based on randomized complete blocks with three replications. Three irrigation intervals including 2, 4 and 6 days were allocated to the main plots. Also, 4 irrigation amounts, calculated based on four coefficients of class A pan i.e. 0.2, 0.4, 0.6, and 0.8 were allocated to the subplots. The results showed that increasing irrigation interval from 2 to 6 days had no significant effects on yield and WUE of Aloe Vera. The least yield, number of leaves per plant, height of bosk was related to the coefficient of 0.2, and there were no significant difference between coefficients 0.6 and 0.8. Also, by decreasing irrigation amounts, WUE increased significantly. The least WUE related to coefficient 0.8, while the maximum belonged to coefficient 0.2. Generally, to achieve the maximum yield (5.7 kg/plant) and WUE (15.5 g/lit), respectively, the coefficients 0.6 (equivalent to 656 mm water for the whole growing season) and 0.2 (equivalent to 219 mm water/season), and for the ease of management, irrigation interval of 6 days are recommended.
Arash Tafteh; Niazali Ebrahimipak; Hossin Babazadeh; Fereydoon Kaveh
Abstract
Management of water distribution in the Qazvin Plain is planned on monthly intervals. Therefore, production functions which can accurately predict yield reduction under deficit irrigation on monthly basis are needed. This study was conducted with the following purpose: assessment of the production functions ...
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Management of water distribution in the Qazvin Plain is planned on monthly intervals. Therefore, production functions which can accurately predict yield reduction under deficit irrigation on monthly basis are needed. This study was conducted with the following purpose: assessment of the production functions using different methods including, minimum, average, multiplicative, Raes method, and product with yield response factor (Ky) power as applied by FAO and Najarchi yield response factors. To estimate tomato yield under different deficit irrigations and evaluation of empirical methods, a study was conducted by using randomized complete block design with irrigation interval treatments including T1, T2, T3, and T4 representing, respectively, 60, 90,120, and 150 mm evaporation from class A pan between consecutive irrigations. The study had three replications and was carried out at the Faizabad Agricultural Research Station, in Qazvin. The results showed that maximum water requirement of tomato plant was 1073 mm, T1 treatment had the maximum yield with 88500 kg/ha and T4 treatment had the minimum yield with 57000 kg/ha. Also, according to statistical comparisons, the proposed method that estimated the plant response factor based on monthly power had the minimum root mean square error (RMSE) and normal root mean square error (NRMSE), while it had the highest agreement index and coefficient of determination (R2).The plant yield response factors were determined in June, July, August, September, and October as, respectively, 0.7, 1.1, 1.1, 1.14 and 0.4. The value of this factor for initial growth, plant development satge, mid-season, and late-season were, respectively, 0.7, 1.1, 1.14, and 0.4, while the average for the whole growing period was determined as 0.89 by using the proposed method. As a result, the proposed method is suggested as a convenient method.