There are more studies about plant bio-stimulants but no clear results about which is the best one in improving vegetable crops specially cucumber. The aim of this study is to screen the effect of various bio-stimulants in improving cucumber (Cucumis sativus L.) growth under soilless culture via root application by modifying coco-peat culture media substrate. In the present study, we tested fifteen treatments as follow: T1 -control (CK); T2 - 10 mM putrescine (Put); T3 - 250 ppm seaweed (Sea); T4 - 0.02 ppm meta-topolin (MT); T5 - 100 ppm naphthalene acetic acid (NAA); T6 - 400 ppm polyaspartic acid (PAS); T7 - 50 ppm sodium nitrophenolate (98% NIT); T8 - 100 ppm tryptophan (AAF); T9 - 1% fulvic acid (FUL); T10 - 107 CFU/ml Bacillus subtilis (BAS); T11 - 106 CFU/ml Trichoderma (TRI); T12 - 50 ppm alanine (ALa); T13 - 150 ppm salicylic acid (SA); T14 - 1 mM silicon (SiO2) and T15 - 0.001 ppm 24-epibrassinolide (EBR). The results obviously showed that using all bio-stimulants significantly increased cucumber growth parameters (plant height, stem diameter, leaves number, leaf area, shoot fresh weight, and root fresh weight). Seedlings Vigor Index (SVI) increased multifold compared with control by all treatments. The increase in cucumber seedlings vigor had a highly significant effect compared with control and the increase was 55.9% followed by 55.2% and 53.4% by Put, MT, and EBR treatments respectively. Our study concluded that the application of plant bio-stimulants can be used to modify coco-peat substrate with a positive effect on plant growth and improvement of cucumber plants under soilless culture.
DOI: http://dx.doi.org/10.5281/zenodo.442027