The Development and Life Cycle of Meloidogyne incognita in sweetpotato (Ipomoea batatas) cv TIS 4400 -2

Abstract

The life cycle and development of root-knot nematode, Meloidogyne incognita, was studied in the roots of sweetpotato (CV TIS4400-2) in a screen house. Three-week old sweetpotato seedlings grown in 16 litre polyethylene pots containing 15 litre steam-sterilized sandy loam soil were each inoculated with 5,000 eggs of M. incognita. Twenty four hours later, and subsequently on a daily basis, two seedlings were randomly uprooted and the roots were cleaned and stained using lactoglycerol method and were examined for nematode penetration and stages of nematode development. The development of M. incognita spanned 30 days at a temperature range of 21.33±0.13 o C to 28.36±0.26 o C : egg to second stage juvenile (J2) (2 days); J2 to third stage juvenile (J3) (10 days); J3 to fourth stage juvenile (J4) (2 days); J4 to young adult (2 days) and young adult to adult females with 441±9.7 eggs (14 days).