Foliar indices for carrot crop using the compositional nutrient diagnosis method1

Frederico Dellano Souza Silva,Natalia Oliveira Silva,Marcelo Rodrigues Dos Reis,Leonardo Angelo De Aquino,Thaísa Fernanda Oliveira

doi:10.1590/1983-40632017v4747584

Abstract

ABSTRACT Carrot has a high yield potential, which requires an adequate and adaptable nutritional management, according to the needs and demands of each crop. Foliar diagnosis is a tool for adjustment and constant improvement of crop fertilization programs. This study aimed to determine leaf indices and reference values using the compositional nutrient diagnosis (CND) method, at three phenological stages of carrot crops [40 and 70 days after sowing (DAS) and at harvest]. In order to calculate the CND method, a database was created with leaf contents of the nutrients N, P, K, Ca, Mg, S, B, Cu, Mn and Zn and root yields, in commercial carrot crops. The nutrient limitation order was generated according to the fertilization response potential. At 70 DAS and at harvest, Mg and Mn were the most limiting nutrients by deficiency, while Zn was the most limiting by excess at 70 DAS, and P and Ca were the most limiting by excess at harvest. The results indicate that the foliar diagnosis performed with the CND method is only effective for the correction of nutritional disturbances in subsequent crops.

Highlights

Concerning olericulture, carrots (Daucus carota L.) stand out for their nutritional and economic importance in Brazil, with an average yield of 31 t ha-1 in the 2014 crop season (ABH 2015)
The mathematical models adjusted between the compositional nutrient diagnosis (CND) indices and the leaf contents in the reference population were not significant at the stage 1 for P, K, S; at the stage 2 for N, K, Mg, S; and at harvest time for S (Table 2)
There was, in general, little agreement between the values published in the literature (Malavolta et al 1997, Hanlon & Hochmuth 2009) and the optimal content and optimal range determined by the CND method (Table 3)

Summary

Introduction

Concerning olericulture, carrots (Daucus carota L.) stand out for their nutritional and economic importance in Brazil, with an average yield of 31 t ha-1 in the 2014 crop season (ABH 2015). The region of Alto Paranaíba, Minas Gerais state, Brazil, has a great importance in the national carrot production, with crop yields superior to the national average, due to local factors (climate, soil and crop management), surpassing 120 t ha-1 in the 2014 crop season (Dezordi et al 2015). Due to their high economic value, carrots require a precise nutrient management.

Objectives

Methods

Results

Conclusion