Nitrogen fertilization impacts biocontrol of tomato gray mold

Abstract

Gray mold, caused by Botrytis cinerea, is a common threat for greenhouse production of tomatoes. Control of this disease can be difficult even with chemical treatments, and alternative methods are needed. Nitrogen (N) fertilization is known to modify the impact of pathogens on plants. However, there is scarce knowledge about the effect of fertilization on the efficacy of biocontrol. Here, we studied the effect of N fertilization on biocontrol agents Trichoderma atroviride and Microdochium dimerum that protect tomato against B. cinerea. Plants were grown for 2 months in a greenhouse with a soil-less drip irrigation system. Differential N fertilization (five concentrations of nitrate) was applied for the last 4 weeks prior to leaf pruning, biocontrol agent application, and B. cinerea inoculation. Results show that increasing N fertilization up to 10 mmol/L reduced disease by half for controls. High N fertilization also increased biocontrol, with a protection index rising from nearly 0 to up to 100 % depending on the biocontrol agent and the pressure of the pathogen. Indeed, high N fertilization delayed stem symptoms and slowed lesion expansion. To our knowledge, this is the first report of an effect of N fertilization on the efficacy of biocontrol against an airborne disease. Therefore, adapting N fertilization is a promising technique to protect greenhouse tomato.

Chitosan nanoparticle based delivery systems for sustainable agriculture

“…Even applied on plants together with biological control agents, chitosan enhanced the efficacy in the control of pathogens [144,145]. Soil amendment with chitosan has frequently been shown to control Fusarium wilts [90,146,147] and gray molds [97,103] in a number of crops.…”

Chitosan antimicrobial and eliciting properties for pest control in agriculture: a review

“…Lots of studies showed that chitosan is not only an antimicrobial agent but also an effective elicitor of plant systemic acquired resistance to pathogens (Table 3). Even applied on plants together with the biological control agents, chitosan enhanced the efficacy in the control of pathogens (Vallance et al 2011;Abro et al 2013). It is possible for chitosan as a new type of green pesticides to play an important role in agriculture owing to its nontoxic, biodegradable, and nonpollution characteristics.…”

The Biocontrol Efficacy of Streptomyces pratensis LMM15 on Botrytis cinerea in Tomato

“…On the other hand, some natural products have undergone research, such as (poly-D-glucosamine) and plant-origin oligosaccharides; they have the ability to elicit defense responses and/or induce protection against B. cinerea in tomatoes and other crops or vegetables [ 15 – 18 ]. Meanwhile, Abro et al [ 19 ] reported that nitrogen (N) fertilization had the ability to strengthen the control efficacy of the biocontrol agents (BCAs) Trichoderma atroviride and Microdochium dimerum . Although N fertilization was a promising method to control tomato gray mold, the key was BCAs.…”

“…Biological control of B. cinerea has been broadly researched [ 19 – 28 ]. Research has shown that the marine yeast Rhodosporidium paludigenum has a significant control efficacy in postharvest tomato fruits via nutrient competition.…”