Advances in Agriculture and Agricultural Sciences

Advances in Agriculture and Agricultural Sciences ISSN 2381-3911 Vol. 2 (3), pp. 085-091, March, 2016. © International Scholars Journals

Full Length Research Paper

Toxicity and preventive action of essential oils in growth of cotton ramulosis Colletotrichum gossypii

José  Baccarin¹, Jorge H. Ambrosio¹ and Antônio Irineu Salles²*

¹Agronomy Department, Universidade Federal Rural de Pernambuco (UFRPE), R. Dom Manoel De Medeiros, S/N, Dois Irmãos, Recife-PE. Cep. 52171-900, Brazil.

²Brazilian Company of Aricultural Research (Embrapa Algodão), Cp 174, Cep. 58107-720, Campina Grande, PB, Brazil.

E-mail: [email protected]

Accepted 7 February, 2016

Abstract

The present study aimed to evaluate the toxicity and preventive action of essential oils in growth of cotton ramulosis, Colletotrichum gossypii var. cephalosporioides, in vitro and in vivo conditions. Six fungus-isolates obtained from cotton belts, in Southern and Mid-West Brazilian regions were submitted to different oil concentrations in bioassays and inhibition of mycelia growth were evaluated during 7 days. Then, the selected oil was used in a preventive bioassay carried out in greenhouse using a susceptible cotton cultivar infected with fungus-conidia at 1.0 × 10⁶ mL-1. Plants in greenhouse were daily evaluated during 30 days. Among all samples evaluated, clove oil at low concentration (500 ppm) provided best results as to fungus-growth inhibition. The disease severity was reduced to 60% in relation to control (no-infected plants). These results mean an interesting alternative in the preventive control of cotton ramulosis, especially to small farmers which often have adopted an agro-ecological management for disease control of crops.

Key words: Colletotrichum, toxicity, control, disease, fungus, growth, ramulosis, inhibition.