Occurrence and seasonal variation of Hemicriconemoides mangiferae from tropical and subtropical orchards in peninsular India.
Ashokkumar P., Vadivelu S., Mehta U. K., Jeyarajan R., Regupathy A.
Author Affiliation: Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore 641003, India.
Nematropica 21 : 167-176
Abstract : Hemicriconemoides mangiferae was prevalent in the major mango (Mangifera indica) and sapota (Achras zapota) [Manilkara zapota] growing tracts in peninsular India. Prominence of Hemicriconemoides spp. increased in sandy loam soils (Prominence value = 108.31). Relative prominence of Hemicriconemoides spp. from 9 geographical locations was 41%. Hemicriconemoides mangiferae, H. gaddi and H. cocophillus were found to be associated with 21 plant species among 19 genera in 17 families. Fourteen of the 18 plant species harboring H. mangiferae are reported to be associated with the nematode from South India for the first time. New additions of host-parasite associations of H. mangiferae are Rosa spp., Artabotrys odoratissimus [A. hexapetalus], and Vitis vinifera. Seasonal variation of H. mangiferae was studied in a 5-year-old sapota field. The population was abundant in October 1986 following monsoon and below detectable levels during a dry winter period in January 1987. Monthly rainfall and mean soil moisture were correlated positively and mean soil temperature was correlated negatively to population level of H. mangiferae. Soil moisture was more critical than soil temperature for the survival of the nematode. Highest population densities were found in the dripline zone at a depth of 20-25 cm in a 5-year-old sapota orchard.