جستجوی مقالات مرتبط با کلیدواژه « irrigation interval » در نشریات گروه « باغبانی »

Supplementary irrigation in the fig orchards of the shores of Bakhtegan Lake in Estahban is done with saline water. This research was carried out to investigate the effect of saline water on vegetative and reproductive characteristics of fig trees. The randomized complete block design was performed with irrigation water salinity treatments (2, 4, 6 and 8 dS.m-1) in two irrigation intervals (once every 15 and 30 days) with a non-irrigation treatment (control) on Sabz cultivar in three replications at Khanehkat village in the years 2018 to 2021. The results showed that irrigation with 8 dS.m-1 salinity had adverse effects and it was an unsuccessful treatment compared to the other treatments with lower salinity irrigation. The highest abnormality symptoms in vegetative and reproductive factors were observed in the control treatment. Also, this treatment has the lowest relative water content (58.6%), diameter (26.6mm) and weight (4.3g) of fruit, the least yield (4935g) and the percentage of first-class commercial fruits (Open ostiole, white and large fruits) and the highest leaf ionic leakage (27.1%), which was significantly different from most of the treatments. There was a great similarity in the characteristics of trees treated with 8 dS.m-1 saline water and without irrigation. Therefore, supplementary irrigation with this salinity is not recommended. In conclusion, supplementary irrigation with saline water less than 6 dS.m-1 had suitable quantity and quality of fruit and the least abnormality signs. So, Sabz cultivar can tolerate until this amount of salinity.

The present study was conducted to evaluate the efficiency of the HYDRUS model in simulating soil water movement and redistribution of moisture around the roots of maize in homogeneous and heavy soils. This study was carried out in the Agricultural Research Center of Khuzestan Province under drip strip irrigation with three irrigation regimes of 2, 3 and 4 days with three replications during two cropping years. In order to monitor the moisture around the roots, dig a soil profile to a depth of 75 cm perpendicular to the drip irrigation strip. Observed and simulated moisture values were compared byR2,EF, MAE and RMSE statistics. The results showed that the average moisture distribution in each irrigation regime is in the range of crop capacity. RMSE values for different diets ranged from 1.29 to 2.40% and MAE values for different diets ranged from 1 to 2%. Moisture simulations were classified as excellent based on MAE and RMSE values.Also, the results of the coefficient of explanation are between 60 to 90% and the efficiency of the model is between 40 to 90%. Based on the results, the lowest efficiency of the model was in the simulation 24 hours after irrigation and the best simulation was 72 hours after irrigation. The results show the high capability of the model in simulating soil volumetric moisture.

Olive (Olea europaea L.) is one of the drought tolerant ever green fruit trees. Olive is an economically important species of the Mediterranean area, so understanding the mechanisms by which olive plants face drought stress under environmental conditions is essential for the improvement of olive yield and oil quality. Olive is one of the fruit trees which become important in the Iranian fruit industry at the near future. Mulch is an optimizing strategy under which crops are allowed to sustain some degree of water deficit and yield reduction. Increasing crop water-use efficiency (WUE) through water conservation in the soil is an important component of dry land farming. Mulching is among the water management practices for increasing WUE. Mulch is referred to as any material that is spread onto the surface of the soil for protection against solar radiation or evaporation. Different materials, such as wheat straw, rice straw, plastic film, grass, wood, and sand, are used as mulches.
This experiment was conducted to study the effect of irrigation interval and mulch on Pomological characteristics and yield of 11-years old Sevillana olive cultivar. A factorial experiment was carried out in Dallaho Olive Research Station at Sarepole located in Kermanshah province. Field experiment based on randomized complete block design with three replications and two factors (irrigation interval and mulch) were conducted in 2015. Each experiment unit consists of 4 trees and 108 trees were used. Irrigation treatments period for experiment were 3, 6 and 10 days interval and mulch treatments for experiment were polyethylene, organic materials and non-mulch (control). Geographical characters was longitude of 45˚, 51΄ E and latitude of 34˚, 30΄ N and the height of sea level 581m. The measured tree characteristics were: Fruit Weight, Pulp Fresh Weight, Pulp Dry Weight, Dry matter, Pulp/Pit ratio, Pit Length, Pit Diameter, Fruit Yield (kg/ tree) and Fruit Yield (kg/ hectare). Reproductive traits were determined by the methods of I.O.O.C.(2002). Collected data were analyzed using SAS program.
Obtained results showed that mulch and interval irrigation treatments had significant differences in Pomological traits so that mulch and 3 days interval irrigation treatments increased fruit weight, pulp fresh and dry weight, fruit moisture percent, fruit yield kg/ tree and kg/ hectare but fruit weight, pulp fresh and dry weight, fruit moisture percent and Fruit yield kg/ tree and kg/ hectare reduced by drought stress. Mulch application increased fruit weight, fruit length and diameter, pulp fresh and dry weight, fruit moisture percent and fruit yield. Mulch application improved Pomological characteristics such as fruit weight, pulp fresh and dry weight, fruit moisture percent, Fruit yield kg/ tree and kg/ hectare of olive Sevillana cultivar under drought stress and helped to save irrigation water in olive orchards. In the arid and semi arid as well as sub-tropical regions, water shortage is a normal phenomenon and seriously limits the agricultural potential. Therefore, under irrigation or rain-fed conditions, it is important for the available water to be used in the most efficient way. The proper irrigation interval can play a major role in increasing the water use efficiency and the productivity by applying the required amount of water when it is needed. On the other hand, the poor irrigation interval can lead to the development of crop water deficit and result in lower yield due to water and nutrient deficiency. Early in the season when plants are small, it is beneficial to encourage the roots to explore as much of the soil profile as possible. This maximizes nutrient uptake and stress tolerance later in the season. The effect of mulch on yield and its components have been reported in various studies. The effect of mulch on plant yield through changes in soil conditions that can change the soil temperature and soil moisture that influence on the growth and yield. The effect of mulch can be done through weed control, make favorable conditions of temperature and soil moisture, reduce leaching of nutrients and soil fertility, increase the efficiency of water use, increase availability of absorption of nutrients, increased root growth and control of diseases and pests.
According to the results of this research, it can be concluded that mulch and interval irrigation had a significant effect on reproductive characteristics. Using mulch improved Pomological characteristics of olive including fruit weight and yield per tree and hactar, fruit length and diameter, pulp fresh and dry weight, fruit moisture percent Under drought stress and helped to save irrigation water in olive orchards.

In order to study the effects of irrigation interval and nitrogen on yield and some physiological characteristics of Fenugreek (Trigonella foenum-gracum L.), an experiment was carried out as split plot in randomized complete block design with three replications at Islamic Azad University of Birjand, 2009. Treatments included irrigation intervals (4, 8 and 12 days) as main plot and nitrogen fertilizer (0, 50, 100 and 150 kg.ha-1 urea) as subplot. Results showed no significant differences for seed yield in irrigation treatments after 4 and 8 days. Increasing N also led to the increase of seed yield but no significant difference was found for seed yield between 100 and 150 kg.ha-1 urea. Decreasing in water use led to the increase of Na, proline and carbohydrate and decrease of K, Cha, carotenoids and total pigments, but it had no significant effect on Chb. Nitrogen significantly increased chlorophyll a, carotenoids, total pigments, and K. Increasing N up to 50 kg ha led to the increase of carbohydrates but then reduced the carbohydrates of leaf. According to the results obtained in this experiment, it can be stated that Fenugreek is somewhat drought tolerant and considering the importance of this medicinal plant, it can be used in conditions of water scarcity as an alternative for the species that have lower economic value under water deficit.

To study the effects of irrigation interval and nitrogen level on yield and yield components of Fenugreek medicinal plant، an experiment in split plot arranged in randomized complete block design with three replications conducted at the Azad University of Birjand in 2009. Treatments included; irrigation intervals (4، 8 and 12 day) as main plot and nitrogen fertilizer (none fertilizer، 50، 100 and 150 kg/ha) as subplot. Results showed that the difference between 4 and 8 days of irrigation intervals for seed yield wasn’t significant، but the highest amount of forage yield achieved from irrigation after 4 days. Rising of nitrogen level led to increase of yield and yield components and the difference between 100 and 150 kg/ha nitrogen for seed and forage yield wasn’t significant. Irrigation interval has a considerable effect on all yield components except of pod length. Nitrogen also has a significant effect on plant height and number of pod per plant but it was insignificant on number of seed per pod، seed weight and pod length. Interaction effect of irrigation and nitrogen indicates that in 4 and 8 days of irrigation intervals، amounts of 100 and 150 kg/ha nitrogen have the highest effect on yield and yield components، but with increase of irrigation intervals to 12 days، 100 kg/ha nitrogen have the highest effect on all traits.

In order to determine the effect of irrigation interval and mulch on growth of olive an experiment was carried out in Dallaho Olive Research Station at Sarepole. A split plot experiment was used based on a completely randomized design with three replications and two factors (mulch and irrigation interval). Each experiment unit consists of 4 trees. Land preparation was done in February 2005 in a 6048 squared meter area then tree planted. Pruning operation was done in next year. Mulch treatments for experiment were control، polyethylene and organic materials and irrigation treatments period for experiment were 3، 6 and10 days interval. Some growth traits including height، trunk diameter and current season growth were measured at the end of growth season. Collected data were analyzed with MSTATC program. Results showed that organic materials mulch and interval irrigation treatments had significant differences in height، trunk diameter and current season growth so that organic materials mulch and 3 days interval irrigation treatments increased height، trunk diameter and current season growth of olive trees. The interaction effect between mulch and irrigation treatments was significance. So that 3 days interval irrigation and organic materials mulch had the highest height، trunk diameter and current season growth. 6 days interval irrigation supplemented with mulch treatment had more significant effect on these traits compared to 3 days interval irrigation alone.

Using mulch to decrease and optimize water use is known as a practical method. For this purpose, a split-factorial experiment based on complete block design with three replications on two melon cultivars was conducted in spring season of 2010 in Torbat-e-Jam. Interval irrigation treatments in three levels (6, 8 and 10 days) were considered as main plot and mulch (straw plus paddy rice, plastic and no mulch) and cultivar (Khatooni and Ghasri) were considered as sub plots in a factorial design. Results showed that there was a significant difference between plactic mulch and the control and also between interval irrigation treatments for fruit yield, ripening period, suger percentage, fruit weight and number of fruits on plants. Interaction effect observed between interval irrigation and mulch for number of fruits on plants, marketable fruit, yield and ripening period traits. The shortest period of ripening was observed for the 8 and 10 dey interval irrigation together with plastic mulch. Plactic mulch caused the suger percentage of both cultivars to increase as well. Plactic mulch for 6 day interval irrigation caused yield and fruit quality to decrease, but it caused yield and fruit quality to increase for more than 8 day interval irrigation. Regarding the advantages of plactic mulch which is the decrease of water use and the improvement of yield and fruit quality, using plactic mulch is recommended for dry land.