Application of NanoMaterials in Plant Protection

H.M.R.HennayakaAG/2011/3175

Faculty of AgricultureUniversity of ruhuna

What are nanomaterials?• Materials, whether of natural or manufactured origin,

possess one or more external dimensions in the range of 1−100nm .

• Nanomaterials fertilizer, Plant protection things - pesticides, fungicides, weedicides Plant pathogen detection tools

Weeds

Plant protection

Pathogen

Pest

Nanopesticide• Small engineered structures with useful pesticidal

properties such as, Stiffness crystalinity permeability, biodegradability large specific area it increased affinity to the target.(Bouwmeester et al., 2009; Bordes et al.,2009)

• Nanopesticide delivery techniques are nanoemulsions, nanoencapsulates, nanocontainers, and nanocages

• Nanomaterials can be used as a coating or protective layer to enable slow release of traditional pesticides and fertilizers ( Corradini et al., 2010)

• Pesticides inside nanoparticles are being developed that can be timed-release or have release linked to an environmental trigger (Nair et al., 2010).

• Examples 1. Formulation of artificial polymer-free nanopermethrin as

an effective larvicide that was stabilized by plant extracted natural surfactants (www.ijcmas.com)

Ex 2 The essential oil from garlic loaded on polymer NPs (240

nm) coated with polyethylene glycol (PEG) to evaluate their insecticidal activity against adult Tribolium castaneum.

Possibility of PEG coated NPs loaded with garlic essential oil for control of storage pests. (Ghormade et al., 2011).

Antifungal activity

• Nano Ag is known to have strong bactericidal and broad spectrum antimicrobial activities.

• It reduces various plant diseases caused by spore producing fungal pathogens.

Ex 1. NP Ag has the antifungal activity on Bipolaris Sorokiniana and Magnaporthe grisea to reduce fungal diseases on perennial ryegrass (Jo et al 2009).

• The efficacy of Ag NPs in extending the vase life of gerbera flowers was also studied and the results showed

- inhibited microbial growth and - reduced vascular blockage

which increased the water uptake and maintained the turgidity of gerbera flowers. (Nair et al., 2010).

Ex 2 • ZnO nanoparticles inhibited the fungal growth of Penicillium expansum by influencing cellular functions, which caused deformation in mycelia mats. (Abd-elsalam 2013).

• TiO2 has excellent efficacy in Oliver cereal like maize by reducing

the effect of Curvularia leaf spot

and bacterial leaf blight disease incidence and severity. (Mahmoodzadeh et al., 2000)

Ex 4• Antifungal activity of NP Cu2O on Phytothphora infestans

with tomato.

• The foliar application resulted in significantly greater protection (73.5 %) from the pathogen, compared to the bulk amendment (57.8 %).(Servin et al., 2015)

Ex 5• Some of the nano particles are used for controlling plant

diseases such as nano forms of C, Ag, Si and aluminous silicates.

• A combination of TiO2,Al and Si was reported to be effective in controlling downy and powdery mildew of grapes. (Bowen et al., 1992)

• The use of nano formulations may offer new ways to enhance the stability of these biological agents (Ghormade et al., 2011).

Nanoherbicide• Herbicides inside nano particles are developed

that can be timed-release or have release linked to an environmental trigger .

• Less herbicide is required to achieve the reduction weed reduction effects .

• If the active ingredient is combined with a smart delivery system, herbicide will be applied only when necessary according to the conditions present in the field. (Gruère et al. 2011a)

Nano fertilizer• Use of nanoscale nutrients to suppress crop disease. • Amendment protocols necessary to maximize plant health

often vary with the level of infection or absence of the pathogen.

• Micronutrients are critical in the defense against crop disease, with tissue infection inducing a cascade of reactions commonly resulting in the production of inhibitory secondary metabolites.

• These metabolites are often generated by enzymes that require activation by micronutrient cofactors.

• The use of nanoparticle-based micronutrient formulations may offer(Singh, 2012)

a highly effective novel platform for crop disease suppression yield enhancement through more targeted strategic nutrition-based promotion of host resistance.

• Nano particles may enter plant leaves through stomata and the cuticle structures.

• NP metals/metal oxides are more effectively translocated than corresponding bulk elements and that this greater transportability exists in both xylem and phloem.

• Sufficient micronutrient content in key tissues will enhance plant defense in the presence of pathogens but a number of factors may limit this supply.

• Nonessential inorganic compounds may play in the activation of host defense mechanisms.Ex1. Mn, Cu, and Zn enhance disease resistance by activating

the host defense enzymes phenylalanine ammonia lyase and polyphenol oxidases. (Evans et al., 2007)

2.Enhanced disease defense may involve non-essential elements such as Al and Si. (Shew et al., 2007)

3.Orthophosphate and CaCl2 amendment increased the levels of phenolic compounds that subsequently reduced damage from Fusarium wilt. (Biswas et al., 2012).

Nanosensors• Nano sensors with immobilized bio receptor probes that

are selective for target analyzing molecules .

• Nano-sensors use to determine the time of crop harvest, detect crop health and determine microbial or chemical contamination of the crop.

• Nano sensors used to diagnose disease caused by infecting soil microorganisms, such as viruses, bacteria, and fungi via the quantitative measurement of differential oxygen consumption in the respiration (relative activity) of good microbes and bad microbes in the soil. (Rai et al., 2012).

Positive effects of Nano materials in crop

protection

• Nano – encapsulated agrochemicals designed in such a way that they possess all indispensable properties such as

effective concentration with high solubility, stability and effectiveness, time controlled release in response to certain stimuli enhanced targeted activity less Eco toxicity with harmless effortless mode of delivery thus avoiding repetitive application.

Negative effects of nano materials• Nano particles on biological systems and the environment

such as toxicity generated by free radicals leading to lipid peroxidation and DNA damage.

• High concentration of nanosilica silver produced some chemical injuries on the tested plants (cucumber leaves and pansy flowers).

• Extremely high doses of these materials are associated with fibrotic lung responses and result in inflammation and an increased risk of carcinogenesis. (Oberdorster et al., 2005)

References• ALEXANDER GOGOS, K. K., AND THOMAS D. BUCHELI 2015. Nanomaterials in

Plant Protection and Fertilization. journal of agricultural and food chemistry. • DIMKPA, A. S. W. E. A. M. R. D. L. T.-R. H. H. J. C. W. P. B. C. 2015. A review of

the use of engineered nanomaterials to suppress plant disease and enhance crop yield. Springer Science+Business Media

• JO, Y.-K., KIM, B. H., AND JUNG, G. 2009. Antifungal activity of silver ions and

nanoparticles on phytopathogenic fungi. Plant Disease, 93, 1037-1043. • R. KHOT A, S. S. A., JOE MARI MAJA A, REZA EHSANI A, EDMUND W.

SCHUSTER 2012. Applications of nanomaterials in agricultural production and crop protection. Crop Protection 35 64-70.

• RATHORE, S. A. A. P. 2014. Nanotechnology Pros and Cons to Agriculture: A

Review International Journal if Current Microbiol Application 3(3), 43-55

Thank you