Integration of Biological and Fungicidal Alternatives for Controlling Foliar Diseases of Vegetables Under Greenhouse Conditions

Abstract

Evaluation the efficacy of bio-agents, resistance chemical inducers and/or thyme oil application as foliar spray against vegetables foliar diseases incidence was carried out in open greenhouse conditions. The tested bio-agents were Trichoderma harzianum, T. Viride, Bacillus subtilis, Pseudomonas flourescens and Saccharomyces serevisiae. Calcium chloride, Potassium monohydrogen phosphate, Potassium bicarbonate, Saccharin, Ascorbic acid, Chitosan and Humic & Folic acid (mixture) as resistance chemical inducers were evaluated. The recorded foliar diseases, i.e. Powdery, Downy mildews of Cucumber, Cantaloupe and Pepper as well as Early, Late blights of Tomato were significantly reduced at all treatments either alone or in combinations comparing with untreated plants. Application with either T. harzianum and B. subtilis showed significant reduction in diseases incidence comparing with the other applied bio-agents. Under artificial infestation the most significant reduction in diseases incidence of tested vegetables were recorded in combined treatments of chemical inducers and S. serevisiae, i.e. (Chitosan + Thyme oil); (Chitosan + Saccharin); (Chitosan + Calcium chloride + S. serevisiae); (Chitosan + Potassium monohydrogen phosphate); (Saccharin + Potassium monohydrogen phosphate) ; (Humic & folic + Thyme oil) and (Chitosan + S. serevisiae) comparing with other applied treatments as well as untreated control.On the light of the present study it could be suggested that the usage of combined application of the bio-agents with resistance plant chemicals might be used as easily applied, safely and cost effective control methods against such foliar plant diseases.

Phytochemical and growth responses of Mentha piperita to foliar application of biostimulants under greenhouse and field conditions

“…CH is a linear β-(1, 4)-glucosamine polymer produced by deacetylation of chitin [23]. The penetration of CH into cells causes the inhibition of interference with the synthesis of mRNA and proteins [24]. The maximum amount of stems dry weight in the greenhouse was observed in 400 mg/l CH + 800 mg/l HA + 400 mg/l CA in comparison with control, while the treatment of 200 mg/l CH + 400 mg/l CA increased the yield of stems dry weight in the field.…”

Pivotal Role of Humic Acid against Powdery and Downy Mildews of Cucumber under Plastic House Conditions

“…Moreover, Pseudomonas and Bacillus spp. were used as antagonistic bacteria against several plant diseases (Abdel- Kader et al, 2012). Organic fertilizers contain some components that increase product quality, root system development and tolerance to diseases, pests and environmental stresses were estimated by Kamel et al, (2014).…”

Chitosan as Source for Pesticide Formulations

“…The mode of action of chitosan is rather variable, depending on its biological target and interacting lipids in the cell plasma membrane [7,8]. Chitosan in combination with different chemicals (e.g., antioxidants, saccharine, essential oil) has been successful for the control of foliar diseases in cucumber, cantaloupe, pepper, and tomato [9]. Low-level copper and chitosan have been provided to confer protection against late blight in potato [10].…”