A Green Nanostructured Pesticide to Control Tomato Bacterial Speck Disease

Abstract

Bacterial speck disease, caused by Pseudomonas syringae pv. tomato (Pst), is one of the most pervasive biological adversities in tomato cultivation, in both industrial and in table varieties. In this work synthesis, biochemical and antibacterial properties of a novel organic nanostructured pesticide composed of chitosan hydrochloride (CH) as active ingredient, cellulose nanocrystals (CNC) as nanocarriers and starch as excipient were evaluated. In order to study the possibility of delivering CH, the effects of two different types of starches, extracted from a high amylose bread wheat (high amylose starch—HA Starch) and from a control genotype (standard starch—St Starch), were investigated. Nanostructured microparticles (NMP) were obtained through the spray-drying technique, revealing a CH loading capacity proximal to 50%, with a CH release of 30% for CH-CNC-St Starch NMP and 50% for CH-CNC-HA Starch NMP after 24 h. Both NMP were able to inhibit bacterial growth in vitro when used at 1% w/v. Moreover, no negative effects on vegetative growth were recorded when NMP were foliar applied on tomato plants. Proposed nanostructured pesticides showed the capability of diminishing Pst epiphytical survival during time, decreasing disease incidence and severity (from 45% to 49%), with results comparable to one of the most used cupric salt (hydroxide), pointing out the potential use of CH-CNC-Starch NMP as a sustainable and innovative ally in Pst control strategies.

Circular Hazelnut Protection by Lignocellulosic Waste Valorization for Nanopesticides Development

“…The residues of a supply chain may become part of the strategy for the sustainable growth and protection of the supply chain itself. The combination of bio-based additives, as active ingredients, and functional nanostructures, as carriers, is one of the most promising tools [25]. Nanoscale structures such as organic nanomaterials can be utilized in the smart delivery of plant-protection inputs, for the encapsulation and entrapment of agrochemicals such as fertilizers, pesticides, herbicides, plant growth regulators, and other active substances, allowing for the slow uptake of active ingredients and reducing the amount of agrochemical applications by minimizing the input and waste [26,27].…”

Crop Protection and Environment: Sustainable Control Measures of Pests and Diseases

“…The NMP tested was able to reduce Pst epiphytical persistence for the duration of time, reduce disease occurrence and severity (from 45% to 49%), as effective as cupric salt (hydroxide) that applied most frequently. These results suggested the prospective use of chitosan hydrochloride formulated with cellulose nanocrystals and amylum nanostructured microparticles to control P. syringae in an environmentally friendly and innovative way [28].…”

Waste valorization by nanotechnology approaches for sustainable crop protection: a mini review

“…tomato (Pst), the causal agent of tomato bacterial speck, when combined with lignin and poly (lactic acid) in ternary films [30]. CNC-based microparticles of chitosan revealed the capability of inhibiting the in vitro growth of Pst as well as the reduction of disease incidence and severity when applied on tomato seedlings, in a comparable way to copper [31]. Currently, only few works have reported antimicrobial activity of waste-based CNC against phytopathogenic bacteria.…”