Abstract

The purpose of this study was to investigate the impact on yields and pest control of extracts from fermented Indigo leaves (Indigofera tinctoria L.) on Chinese Mustard (Brassica chinensis Jusl var parachinensis (Bailey) Tsen & Lee) and Sweet Basil (Ocimum basilicum L.)  For Chinese mustard, comparing crop yields revealed that fermented indigo-leaf extracts of mixed (tea-coloured and blue), tea-coloured and blue varieties gave yields of 24,444.44, 19,222.25 and 19,111.13 kg ha^-1, respectively.  The fermented indigo leaf extracts of mixed (tea-coloured and blue) variety could be most appropriate for preventing and eradicating Phyllotreta sinuata Steph.  For Sweet basil, fermented tea-coloured, blue and mixed (tea-coloured and blue) indigo leaf extract gave yields of 20,333.31, 17,833.31 and 17,555.56 kg ha^-1, respectively. The differences were statistically significant.  The tea-coloured indigo leaf extracts caused decreased population of natural predator (Menochillus sexmaculatus (F.)) in basil plantation.

Key words: Indigo-leaf extracts, yield, pest control, Chinese mustard, sweet basil.