Castor bean cultivars development in relation to depth of sow and dinitroaniline herbicides selectivity

Cleber Daniel de Goes Maciel, Juliana Parisotto Poletine, Edivaldo Domingues Velini, Maurício Dutra Zanotto, Renan Santos Florentino, Leandro Piva Zani, Marcos Cirillo Cruz

Abstract


Three trials were carry out at Garça Municipal County, São Paulo, Brazil in order to study the effects of sowing depth of three castor bean cultivars submitted or not to dinitroaniline herbicides application in pre-emergency. The three cultivars chosen as fllow: AL Guarany 2002 variety and Iris and Savana hybrids. The experiments were disposed in randomized complete blocks, with fifteen treatments and four replications, by using factorial scheme 5x3, composed by sowing in 2,5; 5,0; 10,0; 15,0 and 20,0 cm depths with application in pre-emergency condition of the herbicides: trifluralin (1125 g a.i. ha-1), pendimethalin (1500 g a.i. ha-1) and check without herbicide (hand-hold check). Only the sowing depths of 2.5 and 20.0 significantly reduced the initial development of castor bean cultivars AL Guarany 2002 and Iris, without interfering in characteristics number of leaves, stem diameter, insertion height of first raceme and yield. Trifluralin application has increased significantly AL Guarany 2002 yield, in sowings from 5.0 cm deep, unlike Iris and Savana hybrids, where most of sowing depths studied, resulted in yield declines. Pendimethalin herbicide presented high selectivity mainly for AL Guarany 2002 and Savana cultivars, characterizing, generally as the safest option castor bean crop.


Keywords


Ricinus communis; Seedling emergency; Trifluralin; Pendimethalin.



DOI: http://dx.doi.org/10.5433/1679-0359.2012v33n1p27

Semina: Ciênc. Agrár.
Londrina - PR
E-ISSN 1679-0359
DOI: 10.5433/1679-0359
E-mail: semina.agrarias@uel.br
Este obra está licenciado com uma Licença Creative Commons Atribuição-NãoComercial 4.0 Internacional