Exogenously Applied Chitosan and Chitosan Nanoparticles Improved Apple Fruit Resistance to Blue Mold, Upregulated Defense-Related Genes Expression, and Maintained Fruit Quality

Abstract

Blue rot disease caused by Penicillium expansum is one of the most widespread fungal diseases that affects apples worldwide. This work was to verify the effect of chitosan (2 and 4 g/L) and its nano-form (0.2 and 0.4 g/L) against blue rot disease on apples and their effect on the expression of six defense-related genes as well as fruit quality parameters. Regarding disease incidence, in most cases, chitosan NPs performed better as compared to their raw materials for both artificial and natural infections. The highest efficacy was obtained for chitosan NPs at 0.4 g/L for artificial and natural infection in both 2019 and 2020 seasons. All treatments kept fruit quality parameters regarding firmness, total soluble solids, and titratable acidity for artificial and natural infection in both seasons. As expected, the exogenous application of chitosan NPs and bulk form triggered an increase in the expression levels of six defense-related genes including chitinase, peroxidase, β-1,3-glucanase, Xyloglucan endotransglycosylase (XET), pathogenesis-related protein (PR8), and phenylalanine ammonia lyase-1 (PAL1). Moreover, the highest mRNA quantity of all the studied genes was detected in leaves treated with chitosan NPs at both concentrations compared to other treatments. Chitosan NPs can be considered an eco-friendly and effective approach against blue mold of apples and can be integrated into management programs to maintain postharvest quality and extend the shelf life of fruits.

Application of chitosan nanoparticles in quality and preservation of postharvest fruits and vegetables: A review

“…(2022) indicated that CHNPs synthesized by ionic gelation had a mean size of 56 nm (Figure 1a). Similarly, several reports described the synthesis of CHNPs with a size of 50−100 nm using the same procedure (Abdel‐Rahman et al., 2021; Karimirad et al., 2019; Mohammadi et al., 2015a; Valizadeh et al., 2021). The ionic gelation method allowed the formation of CHNPs with spherical shapes (Figure 1b) (Gohari et al., 2021; Karimirad et al., 2018; Lustriane et al., 2018).…”

“…Although some reports indicated that the ionic gelation technique formed spherical CHNPs (Abdel‐Rahman et al., 2021; Hesami et al., 2021; Karimirad et al., 2020; Karimirad et al., 2018; Saqib et al., 2019), the generated CHNPs showed in general amorphous shapes. Although the shape of the nanoparticles (NPs) is known to affect their properties (Ali et al., 2010; Wang, Shi, Zhu, et al., 2021), the shape of CHNPs was not considered in most studies.…”

“…The efficiency was higher when using 0.5 g/L emulsions than when using 0.2 g/L emulsions. Similarly, in apples, 0.4 g/L CHNPs resulted in a greater enhancement of POD, phenylalanine ammonia‐lyase (PAL), and pathogenesis related‐enzyme (PR8) activities compared to 0.2 g/L CHNPs (Abdel‐Rahman et al., 2021).…”

“…CHNPs have been used for extending the shelf life of different postharvest products (Table 1), including fruits, leaves, such as basil (Hassan et al., 2021), coriander (Ali, Hassan, et al., 2022), lettuce (Paomephan et al., 2018), and marjoram (Amer & Shoala, 2020), flowers, such as roses (Ali, Issa, et al., 2022), and mushrooms (Karimirad et al., 2019, 2020; Karimirad et al., 2018; Karimirad et al., 2018; Valizadeh et al., 2021). The applications of CHNPs in fruits are the most common and cover a wide range of fruit types, including apples (Abdel‐Rahman et al., 2021; Zhao et al., 2021), apricots (Algarni et al., 2022), avocados (Chavez‐Magdaleno et al., 2018; Correa‐Pacheco et al., 2017), bananas (Wantat et al., 2022), blueberries (Medina et al., 2019), cherries (Arabpoor et al., 2021; Ma et al., 2019), chilies (Divya et al., 2018), citrus (Cuong et al., 2022), crabapples (Sun et al., 2020), cucumbers (Cui et al., 2018; Isturiz‐Zapata et al., 2020; Mohammadi et al., 2015b), eggplants (Divya et al., 2018), figs (Aparicio‐Garcia et al., 2021), grapes (Hashim et al., 2019; Silva et al., 2020; Youssef et al., 2019; Youssef et al., 2019), guavas (da Silva et al., 2021), olives (Mohamed et al., 2021), papayas (Allanigue et al., 2017), peppers (Correa‐Pacheco et al., 2021; Gonzalez‐Saucedo et al., 2019; Hernandez‐Lopez et al., 2020; Taheri et al., 2020), persimmons (Nasr et al., 2021; Salem, Tayel, et al., 2022), plums (Mahmoudi et al., 2022), pomegranates (Hasheminejad & Khodaiyan, 2020), raspberries (Ishkeh et al., 2021), strawberries (Hadidi et al., 2021; Hesami et al., 2021; Melo et al., 2018; Mohammadi et al., …”

Chitosan Nanoparticle: Synthesis, Characterization, and Use as Plant Health Materials

“…In vitro assay suggested that synthesized ChNPs in combination with T. asperellum was effective in suppressing mycelial growth of soil-borne fungal pathogens viz., Rhizoctonia solani, Fusarium oxysporum, and Sclerotium rolfsii. Abdel-Rahman et al [50] studied the efficacy of chitosan (Ch) (2 and 4 g/L) as well as ChNPs (0.2 and 0.4 g/L) against blue rot disease of apples caused by Penicillium expansum. They observed that ChNPs performed better than compared to their bulk counterpart for both natural and artificial infections.…”