Different Approaches of Bio-control Agents for Controlling Root Rot Incidence of Some Vegetables under Greenhouse Conditions

Abstract

Different approaches of some antagonistic fungal, bacterial and yeast agents applied as seed treatment or soil drench was evaluated against various soil-borne pathogens causing vegetables root rot disease under greenhouse conditions. The tested pathogenic fungi were Alternaria solani Fusarium solani, F. oxysporum, Rhizoctonia solani, Sclerotium rolfsii, Macrophomina phaseolina and Pythium sp., meanwhile the tested bio-agents were Trichoderma harzianum, T. Viride and Bacillus subtilis, Pseudomonas flourescens and Sacchromyces serivisae. Significant reduction in the disease incidence was observed in bio-agent treatments in comparison with untreated control. Root rot incidence, at pre-emergence stage, significant effect was observed in bio-agent treatments as seed soaking comparing with soil drench treatment. The treated seeds showed a protective effect for seeds germination against the invasion by soil-borne pathogenic fungi. Meanwhile, soil drenched with different bio-agents showed more efficacy for reducing root rot incidence at post-emergence growth stage of tested vegetables, Cucumber, Cantaloupe, Tomato and Pepper. The obtained results revealed that the antagonist T. harzianum showed significant superior effect to reduce diseases incidence followed by B. subtilis. Also, the antagonists T. viride and P. fluorescence occupied significantly the second degree for reducing root rot incidence. The treatment with S. serevisiae had the lowest effect on disease incidence, although it significantly lesser than check control treatment. The present study demonstrates that application of bio-agents as seed treatment and soil drench may be useful for controlling root rot disease in field.

Biocontrol capability of local Metschnikowia sp. isolates

“…In the natural environment, crop surfaces are frequently wetted by rainfall, dewfall, fog, or cloud mist. Therefore, the special hydrophobicity/hydrophilicity of BCA cells may contribute to better adhesion properties to the surface of crops and reduce the overall leaching of yeast cells (Abdel-Kader et al 2012; Krasowska and Sigler 2014).…”

Systemic protection against pearl millet downy mildew disease induced by cell wall glucan elicitors from Trichoderma hamatum UOM 13

“…Many studies have shown that root drench treatment works better than foliar spray (Srivastava et al 2011). Soil drench of T. harzianum and T. viride was more effective than seed treatment in suppressing root rot of vegetables (Abdel-Kader et al 2012). Delivering Trichoderma elicitors through a combined application of different delivery systems will synergize the priming effect and thereby suppress the pathogenic propagules.…”

Impact of Bio Safe Compounds and Resistance Inducers on Certain Soil Borne Diseases, Growth and Yield of Pea Plants (Pisum sativum L.)

“…The experiment was arranged in a completely randomized design with four replicates, each replicate had five pots for each isolate and control treatment. Root rot disease incidence was estimated and calculated as percentage of pre-and post-emergence dampingoff after 15 and 30 days from sowing date, while survival pecent was after 30 days from sowing according to Abdel-Kader et al (2012).…”

“…Likely, treating seeds or foliage treatment of many crops with biocontrol agents such Trichoderma spp. was effective to suppress many pathogens (Abdel-Kader et al, 2012), protect pea and radish seedlings against pathogens attack as well as reducing the incidence of damping-off (Lifshitz et al, 1986). However, Ghanbarzadeh et al (2016) concluded that applying Trichoderma harzianum was less effective for wilt control than the chemical fungicides, but it highly improved growth and yield of onion plants.…”