Effect of volatile fatty acids on embryogenesis and hatching of Meloidogyne incognita eggs

Abstract

Meloidogyne incognita egg masses were immersed in different concentrations of six volatile fatty acids to bioassay their toxic effect on embryonic development and hatching. Exposure to a 250 ppm aqueous solution of volatile fatty' acids completely suppressed egg hatching within 48 hours. When exposed to a 125 ppm concentration hatching was reduced 75 % by acetic acid, 91 % by propionic acid, 23 % by butyric acid, 63 % by isobutyric acid, 41 % by valeric acid and 69 % by caprylic acid during 12 days of incubation. In revival studies hatching did not resume in acetic and caprylic acid-treated eggs even after rinsing in water, whereas it resumed in isobutyric and propionic acid treated eggs. Valeric acid delayed hatching. Results indicated th~t acetic and caprylic acids reduced hatching most effectively and irreversibly by impairing embryogenesis at 'static-vermiform' and 'gastrula' stages respectively.