Synergistic/potentiation interaction between nematostatic constituents from Azadirachta indica, Madhuca indica and Sapindus mukorossi

Abstract

Triterpenic saponins isolated from seeds of Madhuca indica and fruit pericarp from Sapindus mukorossi exhibited inhibitory effect against two phyto-parasitic nematodes. Azadirachtin and salanin-nimbin-desacetylnimbin (SND) was extracted from seeds and oil of Azadirachta indica A. Juss, respectively. M. indica and S. mukorossi saponins were found to inhibit the movement of pre-adult (J₄) stage of Rotylenchulus reniformis with LC₅₀ of 168.8 and 181.9 µg/mL. Azadirachtin and SND affected the mobility of secondary juvenile stage (J₂) of Meloidogyne incognita by 83.3 and 80.1% respectively, at 0.5 mg m/L. M. indica saponin (LC₅₀ 220 µg/mL) exhibited a potentiation effect in the presence of azadirachtin in a 1:3 ratio (LC₅₀ 120.1 µg/mL). A binary mixture (1:1) of azadirachtin and SND was found to show significant nematicidal activity against M. incognita (LC₅₀ 70.9 µg/mL) and R. reniformis (LC₅₀ 91.2 µg/mL).

Keywords:

• triterpenic saponin
• azadirachtin
• Rotylenchulus reniformis
• Meloidogyne incognita
• synergism
• potentiation