Author: M.M. JISKANI, M.A. PATHAN, S.M. NIZAMANI, M.H. SOOMRO, R.D. KHUHRO AND M.A. RUSTAMANI
Publishing Date: 2009
Volume 27 Issue 1
Survey of 37 tomato localities of 8 districts of Sindh, Pakistan viz., Hyderabad, Mirpurkhas, Badin, Thatta, Nawabshah, Larkana, Shikarpur and Khairpur was carried out for assessment of disease incidence, identification of root-knot nematodes associated with tomato roots as well as to observe their frequency and density for determining their occurrence and geographical distribution in Sindh, Pakistan. The root-knot disease incidence (%) was estimated by observing 1850 apparently diseased plants. The incidence was recorded with varying degree from 0 to 60 %. The highest disease incidence (60 %) was recorded in Hoosri followed by Usman Shah (58 %) in district Hyderabad and the lowest (2 %) at Rattodero and Chatto Mangi (Larkana and Shikarpur districts respectively), but there were no root-knot symptoms at Dhamrah, Banguldero, Sattar Bhutto (district Larkana) and Madeji (district Shikarpur). On an overall basis, the maximum incidence was recorded from Hyderabad (56.0 %) followed by Badin (49.2 %), Thatta (45.2 %), Mirpurkhas (39.6 %), Nawabshah (36.8 %) and Larkana (30.4 %) districts; with the lowest at Shikarpur and Khairpur districts (1.0 and 1.2 % respectively). Three root-knot nematode species viz., Meloidogyne incognita, M. javanica and M. arenaria were identified in association with tomato roots. M. incognita was found to be predominant with maximum frequency (52.0 to 100 %), density (285 to 355) and prominence value (205.51 to 289.05), followed by M. javanica and M. arenaria. Their frequency (%), density and prominence value ranged between 30.4 to 40.0, 140 to 165 and 86.85 to 251.31, respectively for M. javanica and remained between 2.3 to 9.5, 35 to 85 and 5.3 to 26.19 for M. arenaria. All the three species were found associated with tomato root samples taken from Hyderabad, Mirpurkhas, Badin, Thatta, Nawabshah and Khairpur districts, but M. javanica and M. arenaria were not found in samples collected from Larkana and Shikarpur districts.