Rain-fed fig trees response to supplemental irrigation timing and potassium fertiliser in micro-catchment (May, 10.1080/14620316.2021.1923409, 2021)

Due to the scarcity of water resources, low quality of available water, and drought occurrence, farmer's tendency to rain-fed farming is increased. In this study, the effect of supplemental irrigation (SI) timing in different months (Rain-fed, March, May, August, March + May) and potassium (K) application at three rates either via foliar spray (0, 1.5 and 3 kg K 1000 L-1) or fertigation (0, 150, 250 g tree(-1)) on soil water balance and growth of rain-fed fig (Ficus carica L.) trees was investigated through a 3-year experiment. Results showed that SI would increase the soil water content, tree evapotranspiration, yield, shoot growth, shoot diameter, number of leaves in a new shoot, leaf width in a new shoot, number of inflorescences, and inflorescence diameter in rain-fed fig trees. Among the irrigation timing treatments, irrigation in March is the best time for the supplemental irrigation of rain-fed fig orchards in severe drought conditions to improve vegetative and generative traits. In addition, application of potassium at the rate of 150 g per tree through fertigation or 3 kg 1000 L water via foliar application is recommended to achieve the highest fruit production in rained fig orchards under drought conditions.