ROOT-KNOT NEMATODE, Meloidogyne javanica (Treub, 1885) Chitwood, 1949 ON PIGEONPEA.
Loading...
Date
1991
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
AAU, Anand
Abstract
The experiments on root-knot nematode (Meloidogyne 1 avanica) affecting pigeonpea were conducted to study (i ) Pathogenicity of root-knot nematode on pigeonpea to determine threshold level (ii) Biochemical changes brought out by the nematode infection in crop, (iii) Histopathological studies to know host - parasite relationship. (iv) Varietal screening for locating source (s) of resistance to the nematode and (v) Assessment of avoidable yield losses due t o nematode infection in field on pigeonpea cv. Pusa Ageti during 1989-90 and 1990-91. The salient findings are as under: i) An inoculum level of 100 neraatodes/plant and above was detrimental to the growth and development of pigeonpea cv. Pusa Ageti. Root, soil and total nematode population/plant significantly increased progressively with an Increase in nematode population from 10 to 10,000 nematodes/plant. Nematode reproduction rate decreased with an increase in inoculxim levels and it was maximum (209.2) in the level of 10 nematodes/plant and minimum (2.63) in 10,000 nematodes/plant. ii) Biochemical changes induced by nematode feeding on pigeonpea roots indicated that roots inoculated with 5,000 and 10,000 M. javanica second stage juveniles/ plant had significantly more peroxidase and polyphenol oxidase activities as well as total phenol contents of the roots over control-no nematode inoculation. iii) Histopathological studies revealed that after invasion, second stage larvae penetrated the epidermal cells and migrated both inter and intracellularly and anchored to the vascular tissues . Giant cells consisted of uneven thickened, unbroken walls, dense cytoplasm and clusters of nuclei. Pathological reactions included abnormal xylem located in the vascular tissues . All nematode stages were fovmd inside the root tissues feeding on vascular region. iv) Out of eighty one different pigeonpea varieties/lines screened against root-knot nematodes, M. javanica, none was found either resistant or moderately resistant to the nematode. Twelve varieties had susceptible and remaining varieties had highly susceptible reaction. v) Application of carbofuran @ 3 kg/ha significantly increased plant height and grain yield of pigeonpea by 5.48 and 16.35 per cent over control respectively. While root-knot index and final soil nematode population got significantly reduced to the tune of 53.94 and 61.43 per cent due to carbofuran treatment over control-no nematicidal treatment respectively. Hence, there was 14 .2 per cent avoidable loss in the pigeonpea yield due to root-knot neraatode infection in field.
Description
Keywords
null, A STUDY