ASSESSMENT OF THREE SEED-BORNE BACTERIA ASSOCIATED WITH TOMATO (SOLANUM LYCOPERSICUM L.) SEEDS AFTER STORAGE AND THEIR EFFECT ON GERMINATION AND SEEDLINGS VIGOR

Abstract

Poor seed quality is a significant factor affecting tomato productivity at the farm level. Tomato seeds were extracted from fruits of five tomato cultivars (Perfect pee, F1-mongal, Dankukumi, UTC-18 andEKT-2) sourced from a conventional DelPHE-5 Research farm,Federal University of Agriculture, Abeokuta, Ogun State. Xanthomonas campestris pv. vesicatoria (Xcv), Clavibactermichiganensis subsp. michiganensis (Cmm)and Pseudomonas syringaepv. tomato (Pst) were isolated from tomato seeds after six months of storage in both 2015 and 2016. Pathogens were identified throughcolony morphology, biochemical and pathogenicity tests. Colonycharacteristics of Xcv and Cmm was determined on yeast dextrosecarbonate (YDC) while Pst was inoculated on Pseudomonas F (PF)medium. Pseudomonas syringae pv. tomato recorded highest frequency of 56.10 and 61.36 % followed by Xanthomonas campestrispv. vesicatoria (31.71 and 22.73%) both in 2015 and 2016 respectively. The germination percentage was determined based on the number of normal seedlings emerged while vigor index was calculated as the product of germination percentage and total seedling length. At7DAS, germination percentage ranged from 83.33 to 16.67% in both Nigerian Journal of Plant Protection (NJPP) Vol. 32, No 1 June. 201849years. At 14DAS, Perfect pee had the highest germination percentage(96.67%) in 2016 which was significantly different (p ≤ 0.05) from the least value (16.67%) recoded in EKT-2 in 2015. Perfect pee had highest significant vigor index of 1,002.70 compared with other cultivars. Results showed that contaminated tomato seeds could be a primary source of inoculum. Therefore, seed treatment would be of high benefit to reduce disease incidence on the field.