j nikbakht; m taheri; m sakaki
Abstract
To evaluate deficit irrigation effect on quantity and quality characteristics of olive fruit (Olea europaea L. cv. Koronaiki), this study was carried out in 2009 in Gilvan (49o 5¢ E longitude, 36o 47¢ N latitude, and elevation 330 m above sea level) located in Tarom region in Zanjan province, ...
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To evaluate deficit irrigation effect on quantity and quality characteristics of olive fruit (Olea europaea L. cv. Koronaiki), this study was carried out in 2009 in Gilvan (49o 5¢ E longitude, 36o 47¢ N latitude, and elevation 330 m above sea level) located in Tarom region in Zanjan province, Iran. Soil texture of the farm was loam. The experimental design was randomized complete blocks with 4 replications. The irrigation treatments were T1, =100% (control treatment), T2= 75%, T3= 50%, and T4= 25 % of olive water requirement (OWR). Trees were watered by drip irrigation system with loop layout. OWR was calculated based on Gilvan synoptic weather station data and FAO Penman-Monteith equation and the FAO-56 recommended crop coefficient.
Based on the results, the effect of deficit irrigation on percentage of fruit oil, ratio of fruit length to diameter, percentage of complete flowers, and percentage of secondary fruits were significant at 1% probability, while the effects on percentage of primary fruits produced were significant at 5% probability. However, deficit irrigation effects on the percentage of fruits dry mass and pulp/pit ratio were not significant. The results showed that the percentage of complete flower produced in T4 was the least (42%). Deficit irrigation caused significant difference (P=5%) between T1 and the other treatments in terms of percentage of primary fruits produced (about 31% difference). Also, deficit irrigation caused differences between percentage of the primary and secondary fruits in T4. Based on the results, difference in ratio of fruit length to diameter between T1 and deficit irrigation treatments were significant (P=5%). Therefore, deficit irrigation was not suggested for cannery objectives. The maximum content of fruit oil (28.49%) and the least content (22.73 %) were obtained from 75% and 25% OWR treatments, respectively. Therefore, in the research site, to irrigate olive trees cv. Koroneiki, 25% continuous deficit irrigation (irrigation with 75% OWR) is suggested in order to save on water use.
r a; r asadi
Abstract
Deficit (or regulated deficit) irrigation is one way to improve efficiency of water use when crop is exposed to a certain level of water stress during a particular growth period. In order to optimizing water use under tape irrigation system, a field experiment was carried out ...
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Deficit (or regulated deficit) irrigation is one way to improve efficiency of water use when crop is exposed to a certain level of water stress during a particular growth period. In order to optimizing water use under tape irrigation system, a field experiment was carried out during 2010 growing season at the experimental farm of Agriculture and Natural Resources Research Center of Orzoueyeh, located in Kerman province. The treatments were laid out in completely randomized block design with three replications., Four water potential thresholds for starting the irrigation treatments were selected by using tensiometers (net water requirement (control) and suctions of 1/2 FC, 1/5 FC and 1/8FC). The crop studied was corn, single cross 704 cultivar. The results showed that water use volumes saved in the three suction treatments consisting of treatments 1/2 FC, 1/5 FC and 1/8FC were 11%, 13% and 17 percent, respectively, in comparison with the control treatment. But, compared to the control, yield of the mentioned treatments decreased by 4 %, 28%, and 34 percent, respectively. However, water use efficiency increased in the 1/2 FC treatment by 6.5% over the control treatment. Statistical analysis of yield components in the control and 1/2 FC treatments demonstrated that these two treatments were in the same group. Among the evaluated treatments, the control and 1/2 FC treatments were economically satisfactory.