محمدرضا غفاریان

Intercropping of forage plants is considered as an effective startegy to achieve optimal yield and increase production in areas with water shortages. A field-based split plot experiment based on a randomized complete block design with three replications was conducted in Ashkezar research farm with the aim of evaluating the intercropping of millet and guar in improving physiological indices and forage yield. Irrigation intervals was considered as the main factor in three levels (irrigation at the time of discharge of 60, 70 and 80% of field capacity) and the cropping system was considered as the sub-factor in three levels (sole cropping of Millet, sole cropping of Guar, and intercropping of Millet and Guar). The intercropping system was implemented as row intercropping pattern with a replacement series design. Results showed that the amount of ionic leakage increased and the relative content of relative water content decreased when irrigation was delayed longer. The highest relative water content for Millet and Guar (70.3 and 78.4%, respectively) were obtained in intercropping system and their lowest relative water content (61.4 and 72.5%, respectively) were obtained in their sole cropping. The highest and lowest chlorophyll indices were observed in irrigation treatments at 60 and 80% of field capacity, respectively. The intercropping of Millet and Guar resulted in increased content of soluble sugar and proline and the highest forage yield compared to their sole culture, in all assessed irrigation intervals. Since intercropping system was shown to cause improved physiological indices of Guar and Millet, the consequent improvement of forage growth and yield could be expected. Overall, it can be concluded that intercropping system of Millet with Guar can significantly reduce the impacts of drought stress and can be considered as an effective management strategy in drought-prone areas.

The goals of study were to evaluate the competitive and economic indices of Kochia, Sesbania and Guar intercropping to select the best cultivation system in conditions of salinity stress.

This experiment was performed at the National Salinity Research Center (NSRC) Yazd-Iran in 2016 and 2017. Three replicates of this split-plot experiment was done using randomized complete block design. The main factor was salinity stress at three levels (irrigation with 4, 9 and 14 dS/m electrical conductivity) and sub-factor, cultivation systems (three sole cropping of Kochia, Sesbania and Guar and their two and three species intercropping.

The results showed that salinity decreased the height of Sesbania and Guar and the mixed cultivation maintained the height of Guar and reduced leaf temperature. The highest percentage of green cover was at 4 and 9 dS/m in three Species, but at 14 dS/m in Kochia sole cropping which had no significant difference with three species. By increasing the salinity from 4 to 14 dS/m, the leaf chlorophyll index of the Guar decreased 21.9% and Sesbania 11.4%, respectively. Intercropping of the three species increased the leaf chlorophyll concentration. The use of mixed cultivation increased the yield of Guar and Sesbania.

Due to the four advantage indices and Relative Value Total at the three salinity levels (1.16, 1.08 and 1.01), it is recommended to replace Kochia sole cropping by three species intercropping.