Effect of Lactobacillus plantarum on germination and growth of tomato seedlings

Significant stimulation of germination of tomatoes (Lycopersicon esculentum Mill. cv Odessa plum) with poor initial germination capacity was achieved by soaking their seeds during 6 h in suspensions of nine out of ten Lactobacillus plantarum strains tested. The increase in percentage of germination ranged from 15.1 to 7.6 %. Lengths of shoots, main and lateral roots and development of root hairs increased after inoculation of seeds with studied L. plantarum strains. The treatments of seeds with L. plantarum expanded shoot lengths by 16.4–18.2 %. Stimulation of main root lengths in the tested tomato seedlings varied from 10.5 to 31.4 %, and the stimulation of lateral roots from 28.6 to 32.2 %. Lactobacilli from different strains exert different effects on the seedlings: for instance, inoculation with certain strains resulted in the stimulation of the main root growth and the inoculation with another strain stimulated shoot growth or growth of the lateral roots. It is the first report about plant-stimulating activities of L. plantarum from different ecological niches (plant surfaces, surfaces of edible mushrooms, dairy products) in the absence of nutritional compounds.