Induction of Anthracnose Disease Resistance on Chili Fruit by Treatment of Oligochitosan—Nanosilica Hybrid Material

Abstract

Oligochitosan (OC) with molecular weight Mw of 5000 g/mol was prepared by gamma Co-60 ray irradiation of chitosan solution. Nanosilica (nSiO 2 ) with the size of 10 -30 nm was synthesized by calcination of acid treated rice husk. The mixture of 1% OC -1% nSiO 2 was prepared by dispersion of nSiO 2 in OC solution. The morphology of nSiO 2 in the mixture of OC-nSiO 2 was measured from images of transmission electron microscopy (TEM). The effect of foliar application of the mixture of OC-nSiO 2 on the induction of resistance against anthracnose disease caused by Colletotrichum gloeosporioides fungus on chili fruits was investigated. Results indicated that foliar application of OC-nSiO 2 with the concentration of 60 mg/l -60 mg/l was found to be as the optimal treatment that reduced the disease severity on chili fruits to 22.2% compared with 90.0% of the control. Thus, OC-nSiO 2 hybrid material could be considered as an effective biotic elicitor to prevent anthracnose disease infection for chili fruits. Furthermore, the prepared OC-nSiO 2 hybrid material can also be used as an environmentally friendly agrochemical product for sustainable development of agriculture.

The use of chitosan oligosaccharide to improve artemisinin yield in well-watered and drought-stressed plants

“…The present study showed a reduction in dry weight and RGR under drought stress where COS treatment did not significantly improve growth parameters. Without stress, chitosan (Ait Barka et al, 2004;Mondal et al, 2016;Harfoush et al, 2017) and degraded chitosan (such as COS) have been reported to improve growth in different species (Dzung et al, 2011;Rahman et al, 2013;Dzung et al, 2017;Muley et al, 2019). However, in A. annua plants under well-irrigated conditions, differences between treatments were not statistically significant.…”

“…Jaleel et al (2017) also found an enhancement in biomass parameters and an increased yield of essential oil and citral content in lemongrass (Cymbopogon flexuosus (Steud.) Wats) treated with COS. Foliar spray with COS improved shoot fresh weight, shoot dry weight and fruit fresh weight of chili (Capsicum frutescens L.) plants (Dzung et al, 2017). Promising results were also obtained with COS-treated wheat seedlings, where growth parameters improved (Zhang et al, 2016).…”

Resistance of cayenne pepper varieties (Capsicum frutescens) to anthracnose disease (Colletotrichum gloeosporioides) isolates from swampy areas

“…Afterward, the topsoil is covered with a damp cloth, and the plants are covered with transparent plastic for 2 days. After 2 days, the cover is removed, and the plants are placed in a shaded area (Dzung et al, 2017;Srisapoom et al, 2021).…”

Management of Fruit Rot of Chilli caused by Colletotrichum capsici

“…Yet another technique could be application of biological substances in the form of nanoparticles. In this direction, oligochitosan from shrimp shells irradiated with Co-60 combined with nano-silicon (10-30 nm), sprayed three times before fruiting as 60 mg L -1 each found effective in controlling the anthracnose infection to the tune of only 22.2 % as against the control with 90 % anthracnose infection (Dzung et al, 2017). Another approach could be the acquired resistance, which is eco-friendly concept through host plant derived signal molecules.…”