Nano silver chitosan against Colletotrichum gloeosporioides anthracnose on mango
Chitosan contains various metal ions such as Ag +, Cu2 +, Zn2 +, Mn2 +, and Fe2 + have been reported to have strong antimicrobial activity. In this study, Nano silver chitosan (AgNPs) were synthesized at 95 ° C using chitosan as a reducing agent and stabilizer. UV-Vis spectrum displayed at the maximum in the range 415-420 nm, the typical surface plasmon resonance band of silver nanoparticles. The size, shape and aggregation properties of the resulting nanoparticles were examined using field emission scanning electron microscopy combined with energy dispersion X-ray spectroscopy.
In vivo trials using isolated mangoes. Alphonso showed that anthracnose was significantly inhibited by the Nano silver chitosan composite. Therefore, this study shows that postharvest rots in mangoes can be minimized with chitosan-AgNP composites and that its application on a commercial scale needs to be exploited. The in vitro germination test showed that the chitosan-AgNP mixture exhibited significantly higher antifungal activity against Colletotrichum gloeosporioides than its components at the respective concentrations.
The Nano silver chitosan mixture, at the concentrations of 0.5 and 1%, showed a decrease in anthracnose by 45.7 and 71.3%, respectively. Chitosan at 0.5 and 1% concentrations showed a reduction of 35.5 and 41.8% (Table 3). On the other hand, combining chitosan-AgNP composite with 0.1% Tween-80 reduced disease by 75.8% at 0.5% concentration and 84.6% at 1% concentration. Combining Chitosan and Tween-80 at concentrations of 0.5 and 1% showed a decrease in incidence of 51.9 and 65.7%, respectively. While carbendazim at 0.0001 and 0.001% showed inhibition of 49.3 and 63.0% when compared with the untreated fruit (Table 3). Anthracnose prevalence was significantly lower (P <0.01) in all chitosan-AgNP seed treatments compared to other treatments (Table 3 and Figure 7).
Interpretation: In the mixture of AgNPs-Chitosan Nano silver is about 3000 ppm and chitosan is about 2000 ppm. The mixture of AgNPs-Chitosan and Tween 80 (0.1%) was at a concentration of 0.5% of the mixture (nano silver 15 ppm and chitosan 10 ppm) 1% mixture (nano silver 30 ppm and chitosan 20 ppm).
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1. Introduce
Chitosan, a chitin demagnetized derivative, is the second most abundant hydrophilic straight-chain polysaccharide found in nature after cellulose. It is made up of N-acetyl-2 amino-2-deoxy-D-glucose (glucosamine) and 2-amino-2-deoxy-D-glucose (N-acetyl-glucosamine) radicals (Aranaz et al., 2010). ). Due to its unique biological properties, such as non-toxicity, biodegradability, biological function, and biocompatibility, many applications have been reported either alone or mixed with Other natural polymers (starch, gelatine and alginates) in food, pharmaceutical, textile, agriculture, water treatment and cosmetic industries (Harish Prashanth and Tharanathan, 2007).
This biodegradable material can also improve the quality of produce and extend its shelf life by minimizing the growth of microorganisms in the product because of its positively charged (multi-cation) nature. Zhong et al., 2009; El Hadrami et al., 2010). The antimicrobial properties of chitosan have been shown against many bacteria, mycelium and yeasts (Kong et al., 2010).
It has an important role in plant protection because of its dual function; antifungal and bactericidal effects and inducing protective reactions (Kendra and Hadwiger, 1984; Sudarshan et al., 1992; Tsai and Su, 1999; Bautista-Banos et al., 2006). The antimicrobial activity of chitosan depends on molecular weight, redox level, pH of chitosan solution and target organism (Helander et al., 2001; Jeon et al., 2001; Zhong et al., 2009).
The antifungal activity of chitosan against Colletrotichum gloeosporioides has been reported (Ali et al., 2010). The antifungal activity of chitosan has also been reported in the fungi Alternaria Alternata, Botrytis cinerea, Rhizopus stolonifer and Phytophthora capsici (El Ghaouth et al., 1992; Xu et al., 2007). Chitosan is highly chelated with various metal ions such as Ag +, Cu2 +, Zn2 +, Mn2 +, and Fe2 + under acid conditions and these chitosan metal complexes have strong antimicrobial activity (Kong et al., 2010). .
The antibacterial properties of elemental silver (Ag) have been extensively studied and have found more medical applications than any other inorganic metal ion, and are not harmful to human cells (Russell and partner, 1994).
Silver can be used to manage plant pathogens in a relatively safer way than synthetic fungicides (Park et al., 2006) because it displays many modalities of inhibitory effects (Clement and Jarrett , 1994). Previous studies provide evidence of the applicability of silver to control fungal pathogens in plants such as Bipolaris sorokiniana, Magnaporthe grisea (Jo et al., 2009), Golovinomyces cichoracearum or Sphaerotheca fusca (Lamsal et al., 2011) and Raffaelea sp. (Kim et al., 2009).
In recent years, significant studies have been carried out to incorporate silver nanoparticles into ultra-thin fibers for many important applications, such as the use of wound dressing materials in the medical field (Zhuang et al., 2010).
Chitosan has been used as a reducing agent and stabilizer to form AgNPs (Murugadoss and Chattopadhyay, 2008). The binding interaction between chitosan and silver nanoparticles leads to the stability of the chitosan-AgNP composite material and therefore, the silver nanoparticles attached to the polymer chain will disperse in the solution when the composite is dissolved.
Mangoes (Mangifera indica L.) are commercially important tropical fruit trees in India, accounting for> 54% of all mangoes produced worldwide. India exports fresh mangoes to more than 50 countries (Tharanathan et al., 2006). Anthracnose caused by C. gloeosporioides is the most important post-harvest disease of mango (Arauz, 2000) and causes rot during storage and transport.
Chemical fungicides were the most effective way to control mango postharvest rot, but their use caused the development of fungicide resistance and increased conflict in the community (Lin et al. al., 2011).
Benzimidazole fungicide has been used to control Colletotrichum disease for the past 38 years, and many resistant cases have been reported due to its very specific mode of action (Hewitt, 1998; Peres et al., 2004).
In view of widespread resistance to benzimidazole fungicides across Colletotrichum species, indigenous alternative safe chemical control strategies need to be developed for anthracnose management before and after harvest.
Previous studies showed that chitosan significantly inhibited the growth of Colletotrichum sp. even lower concentrations (Bautista-Banos et al., 2003; Munoz et al., 2009). Sanpui et al. (2008) demonstrated that the chitosan-AgNP synthetic material is more effective in inhibiting certain bacteria than chitosan alone.
Since no studies have been performed on the antifungal activities of the chitosan-AgNP synthetic material, we hypothesized that chitosan may be useful in plant protection due to its dual function as antifungal agent. Plant defense and antifungal effect, and its activity can be enhanced in conjunction with metal ions in the form of nanoparticles. The objective of this study was to evaluate the chitosan-AgNP synthesis of its antifungal activity against C. gloeosporioides in vitro and its effectiveness in reducing anthracnose in mango fruit.
2. MATERIALS AND METHODS OF RESEARCH
- Chemistry
Chitosan is low molecular weight (85% defatted), and No. 1 Whatman filter paper purchased from Sigma-Aldrich, USA. Silver nitrate (AgNO3, 99.9%) is supplied by Merck, India. Acetic acid (glacial, 99-100%) is from good SD chemicals, India. Tween-80 and sodium hydroxide purchased from HiMedia Laboratories, India. All chemicals were used as received without further refinement. We used double distilled and deionized water throughout the study (MilliQ / Millipore system, Billerica, MA, USA).
- Synthesis of chitosan-AgNP
The nanoparticles were prepared using the one-pot synthesis method of Sanpui et al. (2008) with minor modifications. Briefly, a 100 ml aqueous solution containing 0.2 g of chitosan was kept on a magnetic stirrer with an electric stove at a temperature of 95 ± 1 ° C with continuous stirring. This is followed by adding 2.0 ml of freshly prepared solution of different concentrations (10, 15, 20, 25 and 30 mM) of silver nitrate and 300 μl of 0.3M NaOH, respectively. The pH of the solution is measured to be 10.0. AgNPs formation occurred spontaneously in about a minute, by converting the solution to yellow indicates formation of AgNPs in the medium.
The reaction is allowed to continue for another 30 minutes and cooled to room temperature. The powdered yellow solid was then collected by filtration through Whatman No. 1 filter paper. The powder was washed with deionized water four times, then dried in air and used for further studies.
- Analytical measurements and characteristics
Visible ultraviolet (UV – vis) spectroscopy of all synthesized nanoparticle samples was recorded at room temperature using Infinite 200 TECAN (Seestrasse, Mannedorf, Switzerland) in the range 250– 550 nm. Dynamic light scattering (DLS) and Zeta potential measurements of liquid samples were performed using Zeta pals (Brookhaven Instrument Corporation, Holtsville, NY, USA) at 25 ° C. The aggregation properties of the nanoparticles were examined by scanning field emission scanning electron microscopy (FESEM).
For the FESEM studies, a water suspension drop of the nanoparticle was placed on an aluminum stalk with double-sided carbon tape and kept dry at 70 ° C for three hours. The samples were then kept in a desiccator containing silica gel for 72 hours, and gold particles were splashed over the coating material to prevent the charge effect and were kept under vacuum pressure for the previous 30 minutes. when analyzing. Samples were examined in FESEM using a Zeiss-Ultra 55 model microscope (Carl Zeiss Promenade, Jena, Germany) equipped with energy dispersion X-ray spectral range capability (EDS).
The amount of silver in the nanocomposite was estimated using an atomic absorption spectrometer. A silver stock solution at a concentration of 1 000 μg / mL was prepared by dissolving 1,574 g AgNO3 (equivalent to 1 g of metallic silver) in nitric acid: water (1: 1) and diluting to 1000 ml with water. Milli Q and store in the dark. A Thermo M series atomic absorption spectrometer (Thermo Electron Corporation: Chromatography and Mass Spectrometry, River Oaks Parkway San Jose, CA, USA) used with a silver hollow cathode lamp, at 2 mA and a step operating currents wave and spectrum is 328.1 and 1 nm, respectively.
2.4. Germination of C. gloeosporioides spore treated with a chitosan-AgNP mixture
gloeosporioides isolated (Cm 50 NCBI joining number EF025937) recovered from mangoes grown on dextrose potato agar (PDA) for 7 days under cool white fluorescent light (67.5 mmol m-2 s-1) at 25 ± 1 ° C to promote spores. Spores were washed from PDA plates with 5 ml of sterile distilled water and adjusted to 1.5 x 106 spores / ml using a hemolysis machine (Coal et al., 2008).
A 50 µl solution containing different concentrations of a mixture of chitosan-AgNPs (loaded with 30 mM AgNO3) and chitosan (0.1, 1, 10, 100 and 1000 µg / ml) dissolved in 0.1 % (v / v) acetic acid is added to the well of a chamber slide containing 50 µl of spore suspension.
An equivalent volume (50 µl) of sterile distilled water with 0.1% (v / v) acetic acid is added to the control well. All slides in the chamber were placed in a humid chamber with ~ 95% humidity and incubated for 12 hours at 25 ± 1 ° C, the germination of spores in 20 selected fields determined at the release rate. magnitude 400x under a Zeiss light field microscope (Range Axio. A1, Gottingen, Germany).
Spores are considered to germinate when the length of the germ tube is equal to or exceeding the length of the spore. The percentage inhibited spore germination compared with the control was calculated by the following equation. I = (C-T / C) x100, where, I = percentage inhibited spore germination in the tested pathogen, C = number of germinated spores in the control and T = number of spores germinate during processing. Each treatment had three repetitions and each repetition contained nine slides. The experiment was repeated three times.
2.5. Prepare the coating
The coating solutions were prepared by dissolving a mixture of Nano silver chitosan with 30 mM AgNO3 and chitosan (0.5 and 1.0% w / v) at 40 ° C respectively in 0.5% acetic acid solution. (v / v), since chitosan is only soluble in acidic media. Then, Tween 80 at 0.1% (v / v) was added to improve wettability. The resulting mixture was strongly stirred when heated with a magnetic stirrer for 2 hours until the chitosan was dissolved (Garcia et al., 2010).
2.6. Coating and antifungal activity of the chitosan-AgNP synthetic material on the development of anthracnose on mango
The mango cv. ‘Alphonso’ was collected from a 15-year-old tree grown on the Indian Garden Research Institute’s experimental farm, Bangalore, India, and was used in the experiments. Healthy fruits selected at the semi-ripening stage are of equal size and weight (250 g). The fruit was washed in running water and surface sterilized with 0.1% sodium hypochlorite solution for 2 minutes, then washed with sterile distilled water three times and dried in air.
The fruit was dipped for 15 minutes in sterile water (control), 0.5% acetic acid, chitosan (0.5% and 1%) and chitosan-AgNPs mixture was loaded with 30 mM AgNO3 (0.5%). and 1%) with and without adding 0.1% Tween-80 (v / v).
Chemical tests for carbendazim at 0.001, 0.01%, 0.001 and 0.0001% were also performed to cover the mango and then the coated fruit was dried in air for 30 minutes at 25 ° C. The mango is then injured on the same side (far and near) to a depth of 2 mm by puncturing them with a sterilized pin.
Each wound site was then inoculated with 20 µl of spore suspension (1.5 x 106 spores / ml) C. gloeosporioides. The treated and control fruit were then placed on a wire mesh in a plastic container (45 cm high x 40 cm long x 15 cm wide) containing water, maintained at a relative humidity of ~ 95% and incubated at 24 ± 1 ° C for 7 days. The lesion area (Cm2) was calculated separately by measuring the length and width of each site of infection. The experiment was carried out with three replicates, each repetition had 12 results, so the total number of results for each treatment was 36 results. The experiment was repeated three times.
2.7. Statistical analysis
All data were analyzed statistically using one-way analysis of variance (ANOVA) to determine significant origin and followed by Fishers test to separate means and treatments using Graph pad Prism V.500 for windows (Graph pad software, San Diego, California, USA). Mean value was compared between those treated with the least significant difference (LSD) at 1% (p <0.01). Percent data was converted to arcsin prior to analysis for y = arcsin [sqr (_ / 100)].
3. EXPERIMENTAL RESULTS OF CHITOSAN AND TWEEN SILVER NANO 80
Synthesis and characterization of the Nano silver chitosan nanocomposites. As demonstrated by producing a yellow powder, the reduction of Ag + to Ag NPs was observed in the presence of NaOH and at high temperatures. This indicates that chitosan produces Ag-NP under alkaline conditions. Chitosan acts as a reducing agent and also a stabilizer for NP production.
Yellow powder insoluble in water. The yellow powder of the composite was dissolved in acetic acid and spectrometric UV-Vis. Spectra show that with increasing concentration of AgNO3, there is a gradual increase in peak intensity in the range 415-420 nm (Fig. 1), characteristic surface plasmon resonance (SPR) band of silver nanoparticles, only the formation of silver nanoparticles.
Figure 1. UV-Vis absorption spectrum of chitosan-AgNP composite dissolved in 0.1% (v / v) acetic acid in water. The concentrations of silver ions in the initial solution used for NP preparation were a) 10 mM, b) 15 mM, c) 20 mM, d) 25 mM and e) 30 mM AgNO3, respectively. The amount of chitosan used for synthesis is 0.2 g in 100 ml
The results showed that with the increase in the concentration of silver ions, the concentration of silver nanoparticle formation increased. Table 1 shows the size distribution structures of the chitosan-AgNP composite material loaded with different concentrations of AgNO3. The mean hydrodynamic diameters of the nanoparticles loaded with 10, 15, 20, 25 and 30 mM AgNO3 were 495, 590, 616, 592 and 595 nm, respectively, when analyzed with DLS.
Table 1. Results of dynamic light scattering and zeta potential
The zeta potential is greatly enhanced with the increase in the concentration of AgNO3 (Table 1). Chitosan-AgNP synthetic material has the zeta potential ranging from +50.08 mV to +87.75 mV. When the same sample used for DLS studies was analyzed via SEM, the chitosan-AgNP particles were spherical with a solid solid structure having a particle size in the range of 10-15 nm (Figure 2). When the elemental composition of chitosan-AgNP was determined by EDS, a silver signal was detected, indicating the presence of a significant amount of silver in the nano composite (Fig. 3).
Figure 2. SEM microscope image; a) Synthesis of chitosan, b) AgNO3, c) Chitosan-AgNP mixture (30 mM AgNO3) at 50 K X, and d) Magnification 300 K X.
Figure 3. SEM image and corresponding EDS spectrum for chitosan-AgNP composite
In addition, carbon signals derived from carbon tapes are used to coat the material and the gold signal because gold is sputtering on the surface of the film to prevent the charging effect and improve conductivity (Table 2). The nano mixture prepared from 30 mM AgNO3 has 30,281 mg of silver per gram of chitosan-Ag nanoparticle mixture when analyzed by atomic absorption spectrophotometer.
Table 2. Chemical composition of the elements in the chitosan-AgNP mixture determined by EDS.
- Antifungal activity of the chitosan-AgNP compositeIn this study, the effect of a mixture of chitosan and chitosan-AgNP (Figure 4) loaded with 30 mM AgNO3 (zeta potential of 87.75 mV) on germination of C. gloeosporioides in spores was determined and shown in Figure 6.
Figure 4. Size distribution and zeta potential distribution of the chitosan-AgNPs treated with AgNO3 30 mM
Composite chitosan-AgNP (treated with 30 mM AgNO3) significantly reduced the germination of C. gloeosporioides in the spores compared with chitosan. A mixture of Chitosan-AgNP with concentrations of 0.1 (0.00001%), 1.0 (0.0001%) and 10.0 µg / ml (0.001%) inhibited spore germination, respectively. 44, 70 and 78%. Spore germination was completely inhibited at a concentration of 100.0 µg / ml (0.01%) (Figure 5). Normal germination of C. gloeosporioides was found in sterile distilled water with 0.1% (v / v) acetic acid after 12 hours of incubation on a glass slide. Complete germination of spores was observed at 0.1% acetic acid, so dispersion of the composites with a low concentration of acetic acid did not cause any adverse effects. Results showed that chitosan-AgNP composite treatment prevented germination and was found to be more effective than control.
Figure 5. Effect of chitosan and chitosan-AgNP composite on germination of C. gloeosporioides spore after 12 hours of incubation.
Figure 6. Effect of chitosan-AgNP mixture on germination of C. gloeosporioides in spores a) Normal spore, b) Water control with 0.1% (v / v) acetic acid (formation appressoria), c) Spore germination in chitosan (100 pg / ml) with 0.1% (v / v) acetic acid, d) Completely inhibited spore germination with chitosan-AgNP mixture
- Effects of chitosan-AgNP mixture on mango anthracnose
The chitosan-AgNP mixture, at the concentrations of 0.5 and 1%, showed a decrease in anthracnose by 45.7 and 71.3%, respectively. Chitosan at 0.5 and 1% concentrations showed a reduction of 35.5 and 41.8% (Table 3). On the other hand, combining chitosan-AgNP composite with 0.1% Tween-80 reduced disease by 75.8% at 0.5% concentration and 84.6% at 1% concentration. Combining Chitosan and Tween-80 at concentrations of 0.5 and 1% showed a decrease in incidence of 51.9 and 65.7%, respectively. While carbendazim at 0.0001 and 0.001% showed inhibition of 49.3 and 63.0% when compared with the untreated fruit (Table 3). Anthracnose prevalence was significantly lower (P <0.01) in all chitosan-AgNP seed treatments compared to other treatments (Table 3 and Figure 7).
Table 3. Efficacy of chitosan-AgNP mixture and treatments for mango anthracnose caused by C. gloeosporioides
* Values in parentheses indicate percentage of control inhibition. The inhibition percentage was calculated based on data collected seven days after inoculation. The inhibition percentage is calculated by the formula [C-T / C] (100)], where C is the lesion size of the control fruit and T is the lesion size of the treated fruit (cm2). Percent data was converted to arcsin prior to analysis for y = arcsin [sqr. (_ / 100)]. Data are means and standard deviations of three independent experiments. Each experiment had three repetitions. Each replication contains 12 fruits and two transplanting points. Each row value followed by a lower case letter differs significantly at p <0.01, according to Fishers’ LSD test. BHealthy Mango Cv. Alphonso, treated with chitosan-AgNP composite with different concentrations compared to other test and control chemicals, was placed in a plastic container (45 cm high x 40 cm long x 15 cm wide) containing water to maintain the maintains moisture and is used for biological assay against C. gloeosporioides Cm 50
Figure 7. Effect of nanocomposite on mango against anthracnose a) Control, b) carbendazime (0.001%), c) 1% chitosan, and d) 1% Chitosan-AgNP composite with Tween-80
4. DISCUSSION EFFICIENCY NANO SILVER CHITOSAN
The chitosan structure differs in molecular weight and redox level. The main amine and hydroxyl groups in chitosan show high affinity for metal ions by chelation. Chitosan is a biodegradable poly- mer in the presence of NaOH and at high temperatures reduces and stabilizes AgNO3 into silver nanoparticles.
Different silver nitrate concentrations are reduced to the corresponding Nano silver at specific temperatures. Nanoparticle formation was determined by UV-Vis spectroscopy. UV-Vis absorption spectrum shows sharp peaks in the 415-420 nm range, the characteristic surface plasmon resonance (SPR) band of silver nanoparticles (Wei et al., 2009), supporting the formation of Silver nanoparticles on chitosan background. For nano suspensions, the size distribution and zeta potential are important characteristic parameters (Muller et al., 2001).
When analyzing Chitosan-AgNP composites with different concentrations of AgNO3 analyzed with DLS, the samples showed a size distribution in the range 495 – 616 nm. The zeta potential of ± 30 mV is the minimum requirement for the electrostatic repulsion of the physically stable nanoscale, indicating the degree of repulsion between similarly charged particles and the stability of nanoparticles in the capacitance. translation (Muller et al., 2001; Du et al., 2009). The zeta potential is greatly enhanced with an increase in the silver load on the nanocompozite between +50.08 and +87.75 mV. These data indicate that the nanomaterials prepared with different AgNO3 properties are highly stable.
In order to match the presence of silver nanoparticles in the mixture, SEM measurements were performed, the chitosan-AgNP synthesis sites showed spherical particles with a dense structure with a particle size in the range of 10-15 nm. The significant reduction in nanocompozite size can be explained by two main explanations, the first is the association of a large number of water molecules with the nanocompozite when we surveyed through the DLS, while in the field. SEM imaging, water was removed during sample preparation. The second significant difference is due to large chitosan particles present in bulk solution during DLS analysis, while in SEM no larger particles are considered for diameter measurement. EDS taken during SEM imaging showed a prominent silver signal, indicating the presence of silver in nanocomposites.
The main postharvest losses of mango are due to fungal infections, physiological disturbances and physical damage, and the chitosan coating is capable of prolonging storage and controlling mango decay (Kittur et al. , 2001). Researchers have used several types of plant essential oils as postharvest pesticides to manage anthracnose on mangoes (Abd-AllA and Haggag, 2013). Mohamed et al. (2013) showed the antifun-gal activity of the chitosan membrane on the inhibition of C. gloeosporioides in relation to mango.
In this study, we evaluated the applicability of the Nano silver chitosan composite as a fruit coating material to inhibit the growth of C. gloeosporioides. Nanocomposites showed greater efficacy in reducing the rate of rotting fruit tissue.
Tween alone did not have a significant effect in inhibiting spores, but the addition of the non-ionic surfactant Tween 80 to nanocomposites enhanced the wetting and adhesion of the coating solution, which did not allow emitting. Normal growth of spores and disease reduction were higher than with other treatments.
Previously, chitosan nanoparticles with enhanced zeta potential have shown excellent inhibitory effects on microorganisms (Qi et al., 2004). In this study, the chitosan nano-silver mixture significantly reduced the germination of C. gloeosporioides in spores compared with the control and other controls.
In mangos, the postharvest stage of anthracnose caused by C. gloeosporioides is the most economically significant and devastating period, and this is directly linked to the field stage where the infection is infection occurs on the developing fruit and infection remains dormant as appresoria and under scale mycelium until ripening begins (Arauz, 2000). Presently, the elimination of the silent infection is commercially available with heat and chemical treatments or a combination of the two (McMillan, 1987).
Temperature and time control is important, because fruit can easily become stained from overexposure to heat, and it takes time and effort. In this study, we demonstrated that chitosan-AgNP synthetic material is more effective than chitosan in inhibiting germination of C. gloeosporioides spores and inhibiting anthracnose on mango. In nano form, silver appears more toxic than large types of silver. Therefore, these nanomaterials can be coated as a coating material in order to prevent C. gloeosporioides from growing on mangoes to avoid postharvest losses.
5. Conclusion
Nano silver with size 10-15 nm were prepared using low molecular weight chitosan as reducing agent and stabilized at 95 ° C. The results of UV-Vis, EDS and FESEM spectra were confirmed. presence of silver nanoparticles and structure of chitosan-AgNP composite. As a result, this mixture successfully inhibited germination in C. gloeosporioides spores and also reduced the incidence of anthracnose on mango. This could find applications in preventing Colletotrichum infections on mangoes to prevent major crop damage and boost exports.
Reference source: Antifungal activity of chitosan-silver nanoparticle composite against Colletotrichum gloeosporioides associated with mango anthracnose
P. Chowdappa*, Shivakumar Gowda, C. S. Chethana and S. Madhura
Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bangalore-560 089, India