Relationship between incidence of Leucinodes orbonalis (Guenee) and Chlorophyll content in leaves of Brinjal (Solanum melongena L.)

The present study on biochemical basis of resistance against Leucinodes orbonalis infestation was conducted during the year 2011-2012. The results revealed that highest chlorophyll-‘a’- content of 0.497 mg/gfw was recorded in the susceptible genotype SHB-1.The lowest amount of 0.319 and 0.381 mg/gfw was observed in the resistant genotypes Brinjal-85 and Local long respectively, which were significantly different from other evaluated genotypes. The chlorophyll ‘a’content was positively correlated with the brinjal shoot and fruit borer infestation. Thehighest chlorophyll -‘b’- content of 0.442 mg/gfw was recorded at 70 DAT (days after transplanting). The amount of chlorophyll -‘b’- varied significantly among the genotypes at different ages and decreased with the age of crop. The average highest amount of chlorophyll -‘b’- was estimated in the genotype SBH-1 which was significantly at par with hybrid SBH-2. The lowest chlorophyll -‘b’- content was recorded at 40 DAT in the genotype Brinjal-85 followed by Local Long. The lowest amount of total chlorophyll was estimated in the resistant variety as compared to susceptible therefore exhibiting lowest level of infestation

Characterization of Biocontrol Agents Isolated From Temperate Region of India

Trichoderma species are potential fungal bio-control agents used against a wide range of soil borne plant pathogens. In the present study a total of 20 Trichoderma isolates viz., AT1, AT2, AT3, AT4, AT5, AT6, AT7, BT1, BT2, BT3, BT4, BT5, BT6, BT7, BT8, BT9, BT10, BT11, BT12, BT13 were isolated from vegetable fields of Kashmir valley and their efficacy was tested by using various biochemical tests. Thirteen isolates of Trichoderma viz., AT1, AT2, AT3, AT4, AT5, AT6, AT7, BT1, BT7, BT8, BT10, BT11 and BT12 were found to be positive for ammonia production. Similarly twelve isolates viz., AT2, AT3, AT7, BT1, BT3, BT4, BT7, BT8, BT10, BT11, BT12 and BT13 were found to be positive as far as the chitinase activity is concerned. In the IAA production assay maximum IAA was produced by isolate BT9 (6.605 µg mL-1) followed by BT6 (5.278 µg mL-1), while minimum IAA was produced by isolate AT1 (1.538 ìg mL-1). Only five isolates viz., AT1, AT2, AT3, AT4 and AT5 metabolized lactose and sucrose while seven isolates viz., AT1, AT2, AT3, AT4, AT5, AT6 and AT7 were found to metabolize maltose. Hydrocyanic acid (HCN) was observed to be produced by only three isolates of Trichoderma viz., AT3, AT5 and AT7. Trichoderma isolate AT3 qualifying most of the biochemical tests were morphological characterized as Trichoderma harzianum