Response of chilli crop to different nitrogen fertigation and irrigation frequency under drip system using marginally saline water

Abstract

In India, sustainable development and efficient management of water is a complex challenge which is going to increase day by day. Some parts of Haryana and Punjab are underlain by brackish to saline groundwater and inadequate canal network. Areas which mainly depend on canal water irrigation which restrict the pumping of saline groundwater and develop waterlogging as well as soil salinization with a rapid rise of the water table. In this situation, its exploitation is necessary to arrest the rise in water table and saline water use for crop production. This study aimed to explore the performance of chilli crop in relation to differential nitrogen and irrigation using marginally saline water under drip system. Irrigation of marginal quality (EC ~ 2.5 dS m-1) water was scheduled on daily (I1) and alternate day (I2) bases with combination of three fertigation levels (F1: 75% RDN, F2: 100% RDN and F3: 125% RDN) and surface irrigation (Si) with 100% RDN as control with three replication. The highest yield (10.69 t ha-1) was obtained under daily drip irrigation with 125% RDN (I1F3), followed by 100% RDN (I1F2) having 10.23 t ha-1 yield. In daily irrigation, 28.2% and 34.0% more yield was obtained in I1F2 and I1F3 in comparison to I1F1. Among the drip irrigation, I1F3 treatment has obtained the highest water use efficiency (4.17 kg m-3) and its lowest value 3.19 kg m-3 was obtained in I2F1 treatment. The highest NUE (172.2 kg of chilli per kg of Nitrogen) was obtained under daily drip irrigation with 75% RDN (I1F1), followed by 100% RDN (165.6 kg of chilli per kg of Nitrogen). The highest nitrogen uptake (64.99 kg ha-1) was obtained under daily drip irrigation with 125% RDN (I1F3), followed by 100% RDN (I1F2) having 61.68 kg ha-1. With respect to irrigation frequencies as well as different RDN levels, nitrogen uptake was found significantly different.