Insect Pest Abundance on Sweet Basil, Ocimum basilicum L. (Labiatae) Under Different Production Systems

Abstract

Insect pests are often the major constraint for exportation of sweet basil. This study revealed the abundance of insect pests on sweet basil under organic, good agricultural practice (GAP) and conventional production systems in central Thailand from February 2010 to January 2011. In total, 6,886 pest specimens from 8 species were collected from all fields while only 2 species of natural enemies were recorded. In total, 4,119 individual insect pests were recorded in the organic field while the numbers in GAP and conventional fields were 1,418 and 1,349, respectively. In every sweet basil production system, thrips (Bathrips melanicornis) were the most common pest. In general, 8 out of 12 monthly diversity indices from the organic system were higher than those from either the GAP or conventional systems. The highest diversity index recorded from the organic farms was in August (1.63) while the highest diversity index from the GAP system (1.61) was recorded in September and from the conventional system (1.42) in October. Since Thailand is a global exporter of sweet basil, this study provides important reference information for importing countries, and represents a form of protection for sweet basil exports from Thailand to the global market.