Determination of irrigation management indicators in peach and nectarine production in Iran

Providing food security in scarcity conditions of water resources requires macro-planning for the supply, allocation and water consumption in different sections such as agricultural section. In Iran, like in other countries of the world, most fresh water resources are consumed in the agricultural sector. In this situation, one of the effective and practical solutions is the optimal use of irrigation water in the agricultural sector, which consumes the most water. The most basic component for optimal irrigation water management in Iran is the awareness of applied water in the production of various agricultural products under the farmers’ management conditions. Therefore, this study was conducted with the aim of appraising irrigation water management indicators such as seasonal applied water, yield , and irrigation water productivity, total water productivity (irrigation water plus plus effective rainfall ) in Azarbayjan Sharghi, Azarbayjan Gharbi, Ardabil, Alborz, Tehran, Chaharmahal and Bakhtiari, Fars, Qazvin, Markazi, Hamedan, Golastan and Mazandaran provinces as peach and nectarine production hubs in Iran.

In this study, a field survey was conducted to measure applied irrigation water and yield under the gardeners’ management in peach and nectarine production hubs. This indicators was measured in 195 gardenes in Azarbayjan Sharghi, Azarbayjan Gharbi, Ardabil, Alborz, Tehran, Chaharmahal and Bakhtiari, Fars, Qazvin, Markazi, Hamedan, Golastan and Mazandaran provinces with different conditions of climates, irrigation methods (surface and drip), salinity of irrigation water and soil; and different peach and nectarine cultivars during growing season 2018-2019. To measuring irrigation water volume, after determining the inflow of water to the garden by carefully monitoring the garden irrigation time and measuring the irrigated area, the volume of irrigation water applied by peach and nectarine trees in each garden was measured. Crop yield was obtained in three consecutive years and their mean was used in the analysis. Irrigation water productivity (WPIrr) and total water productivity (WPIrr+pe) were calcucated as the ratio of yield to applied water and irrigation water plus effective rainfall, respectively. Then, the effect of modern irrigation methods (surface drip irrigation) on applied water, WPIrr and WPIrr+pe were investigated in the study areas. Analysis of variance was used to investigate the possible difference between yield, applied water and WP among the hubs. Data adequacy was assessed by using the method provided by Sarmad et al. (2001)

The results showed that the difference between average volume of water applied by gardeners, yield, WPIrr and WPIrr+pe, in the studied sites were significant at 5% probability level. The average amount of applied water by gardeners in Azarbayjan Sharghi, Azarbayjan Gharbi, Ardabil, Alborz, Tehran, Chaharmahal and Bakhtiari, Fars, Qazvin, Markazi, Hamedan, Golastan and Mazandaran provinces was 8617, 7178, 8140, 8137, 8568, 7763, 8814, 8675, 10806, 6428, 2842 and 2012 m3/ha, respectively, and the average was 6734m3/ha. The yield of peach and nectarine varied from 10 to 50 tons/ha with an average of 20 tons/ha. Irrigation water productivity (WPIrr) varied from 1.6 to 8.6 and its average was 3.06 kg/m3. The average WPIrr+pe for peach and nectarine was 2.44 kg/m3. The results showed that the average applied water for peach and nectarine orchards in the study areas except for Golestan and Mazandaran provinces for surface and drip irrigation methods were 9325 and 7098 m3/ha, respectively, (p<1%). Therefore, in drip irrigation method, applied water was 25% less and WPIrr was 34% higher.

In general, the results of this study provide useful information on irrigation water management indicators in peach and nectarine production to managers and water decision makers within Iran. Accordingly, in order to reduce the volume of irrigation water and improve peach and nectarine water productivity, it is recommended to use drip irrigation method in suitable climatic conditions where irrigation water is of good quality and the technical criteria of design, implementation, operation, and economic considerations are met. Also, training and application methods to improve the performance of surface irrigation to reduce evaporation and applied irrigation water is recommended.