Estado nutricional e acúmulo de nutrientes em coentro fertirrigado por gotejamento contínuo e pulsado

Abstract

The pulse irrigation appears to give support for handling and promote increases in the quantity and quality of the products. This technique has presented resulted significantly with respect to the water economy, however, little is known on its relation to the mineral nutrition of the plants. Coriander (Coriandrum sativum L.) is an important vegetable in the socioeconomic scenario of the country, there is little information about mineral nutrition and cropping systems. The objective of this study was to evaluate the effect of pulsed and continuous drip irrigation on nutritional status and accumulation of dry matter and nutrients by coriander. The experiment was conducted from August to September 2017, in a protected environment in the Agronomy Department of the Universidade Federal Rural of Pernambuco - Recife, PE, Brazil. The design was a randomized complete block design in a 2 x 5 factorial schemes with three replications. The treatments were composed of two types of fertigation application (pulsed and continuous fertigation) and five fertigation replacement blades (40, 60, 80, 100 and 120% of the crop evapotranspiration - ETc). For the pulsed fertigation, six pulses with a 60-minute rest interval between two applications were defined. Pulsed fertigation combined with ETc replacement blades lower than 100% provided higher P, S, Fe and Mn leaf contents. Continuous fertigation with the 100% ETc blade induced sulfur deficiency in the crop and, combined with 40% blade provided the highest Ca content. ETc replacement blades from 82.7 and 40%, regardless of the type of application, provide nitrogen and magnesium foliar contents, respectively. Continuous fertigation reduced potassium leaf content and pulsed magnesium contents, but not to the point of causing nutritional disorder. The ETc replacement blades positively influenced the accumulation of dry matter and of all nutrients (N, P, K, Ca, Mg, S, Fe, Mn, Cu and Zn) studied. Pulsed fertigation promoted the highest accumulations of dry mass, N, P, K, Fe, Mn, Cu and Zn, and reduced the accumulation of Ca by the crop. The highest accumulations of K, Mn, Cu and Zn were obtained with the application of pulsed Fertigation combined with ETc replacement blades lower than 100%. The accumulation of nutrients by the crop in both types of fertigation application decreased in the following order: K> N> Ca> P> Mg> S> Fe> Mn> Zn> Cu.