Occurrence of Rice Root-Knot Nematode and Yield Loss Assessment in Aligarh and Hathras Districts of Uttar Pradesh, India Khan Mujeebur Rahman*, Anwer M. Arshad Department of Plant Protection, Aligarh Muslim University, Aligarh-202002, India *E-mail: mrkhan777in@yahoo.co.in
Online published on 12 April, 2012. Abstract Surveys were conducted in Aligarh and Hathras districts of Uttar Pradesh to determine frequency of occurrence and disease incidence of rice root-knot nematode, Meloidogyne graminicola in paddy fields. One hundred eighty paddy fields were surveyed in all blocks of the five tehsils of Aligarh and four tehsils of Hathras district. M. graminicola was found widely distributed in most of the rice growing localities in all tehsils. Most of the farmers grow two export varieties of paddy cv. Sugandh-5 and Pusa 1121 which were found highly susceptible to the nematode and exhibited 16 to 41% yield loss compared to the field not infested with M. graminicola in the locality. Frequency of disease occurrence in the Aligarh and Hathras districts was found to be 40% and 27%, respectively. Among various tehsils in the district Aligarh highest frequency of occurrence was recorded in the Koil (77.5%) and lowest in Khair (11.5%). In the Hathras district, the frequency of occurrence was found greatest in the tehsil Sasni (31.5%) and lowest in Sadabad (18%). Disease incidence in the Aligarh and Hathras districts was found 69 and 48%, respectively. Maximum incidence of root-knot in Aligarh and Hathras district was found in Iglas (76.5%) and Hathras (50%) tehsils, respectively. Disease severity on 0–5 scale was recorded 4.5 gall index in Iglas tehsil (Aligarh) and 3.0 GI in Sasni tehsil (Hathras district). Consequently greatest yield decline in Aligarh was recorded in Iglas tehsil (up to 60.8%) and in the district Hathras it was 32% in Hathras tehsil. Overall the disease occurrence, incidence, severity and yield loss to paddy were much greater in the fields/localities with lighter soil (sandy loam) than heavier soils (clay loam). Top Keywords Meloidogyne graminicola, paddy, galls, egg masses, soil population, western Uttar Pradesh. Top |