Effect of seed bacterization and methods of application of Pseudomonas fluorescens on the control of Rotylenchulus reniformis infecting tomato

Abstract

A glasshouse study was conducted in which the efficacy of Pseudomonas /luorescens strain Pfl was evaluated as seed bacterization, soil drench, and bare root dip alone or seed bacterization followed by soil drench or bare root dip on tomato. Seed bacterization resulted in 90% germination compared to 81 % in non-bacterized seeds. Seedling weight and shoot length were improved by 54 and 18%, respectively, 21 days after sowing. Root colonization by the rhizobacterium in terms of cfu/g and cm fresh root of the seedlings raised from bacterized seed increased with increasing observation time. Further, it was found that the strain Pfl when applied as seed bacterization, soil drench and bare root dip either singly or in combination caused a significant reduction in nematode penetration of Rotylenchulus rem/ormis compared to the untreated control. The maximum reduction of 55% of nematode penetration occurred when the bacterium was applied as seed bacterization followed by a soil drench. Application of the bacterium alone or in combination with the seed bacterization and soil drenching/root dip improved growth characters of the tomato plants, except root length. The multiplication rate (PflPil of the nematode was also significantly reduced in all of the treatments receiving bacteria with the maximum (45%) in the treatment that received seed bacterization followed by a soil drench.