Effects of phosphonate and salicylic acid treatments on anthracnose disease development and ripening of 'Kensington Pride' mango fruit

Abstract

This study investigated treatment of mango (Mangifera indica L.) fruit with 2 host defence-promoting compounds for suppression of anthracnose disease (Colletotrichum gloeosporioides). Cultivar ‘Kensington Pride’ fruit were treated at concentrations of up to 1000 mg/L with either potassium phosphonate or salicylic acid. Applications were by various combinations of pre- and postharvest dips and vacuum infiltration. Postharvest treatments at up to 2000 mg/L salicylic acid were evaluated in a second fruiting season. Fruit were either uninoculated or inoculated with the fungal pathogen. Colour, firmness and disease-severity were assessed during shelf life at 23°C. There were no significant (P>0.05) effects of potassium phosphonate or salicylic acid on anthracnose disease severity in the first season. Moreover, phosphonate or salicylic acid treatment did not significantly affect fruit colour or firmness changes. There were significant (P<0.05) reductions in anthracnose severity in the second season, especially at the highest concentration of 2000 mg/L salicylic acid. Mango fruit skin colour and firmness changes were also slowed down significantly (P<0.05). These effects of salicylic acid were attributed to inhibition of mango fruit skin ripening (senescence).

Enhancement of Postharvest Disease Resistance in Ya Li Pear (Pyrus bretschneideri) Fruit by Salicylic Acid Sprays on the Trees during Fruit Growth

“…Studies have shown that SA treatment can enhance disease resistance of a few growing plants or detached plant organs (Sticher et al, 1997;Meena et al, 2001;Zainuri et al, 2001;Qin et al, 2003). Our study indicated that postharvest disease resistance of Ya Li pear fruit could also be notably enhanced by foliar SA sprays on the trees during the growth season.…”

“…SA is a simple phenolic compound naturally produced by many plants and has been considered as a signal molecule in the signal transduction pathway in plants (Malamy et al, 1990;Sticher et al, 1997). A few studies have shown that disease resistance in fruit could also be induced by postharvest treatment with SA (Qin et al, 2003;Zainuri et al, 2001). It has been demonstrated that pre-harvest application of SA tended to suppress postharvest anthracnose disease severity caused by Colletotrichum gloeosporioides in mango fruit (Zainuri et al, 2001), and that application of acibenzolar-S-methyl, a functional analogue of SA, on melon plant prior to flowering could effectively inhibit infections of several postharvest fungal diseases in melon fruit (Huang et al, 2000).…”

“…A few studies have shown that disease resistance in fruit could also be induced by postharvest treatment with SA (Qin et al, 2003;Zainuri et al, 2001). It has been demonstrated that pre-harvest application of SA tended to suppress postharvest anthracnose disease severity caused by Colletotrichum gloeosporioides in mango fruit (Zainuri et al, 2001), and that application of acibenzolar-S-methyl, a functional analogue of SA, on melon plant prior to flowering could effectively inhibit infections of several postharvest fungal diseases in melon fruit (Huang et al, 2000). However, little is known about how disease resistance in harvested fruit of woody plants may be affected by SA treatment on the trees in the field during fruit growth and development.…”

Mango

“…The use of various chemical, physical and biological elicitors can artificially induce host resistance (Wilson et al 1994). The exogenous application of salicylic acid (SA), which is involved in the disease resistance in plants, has been demonstrated to be effective in enhancing the disease resistance in mango fruit (Zainuri et al 2001;Zeng et al 2006). The post-harvest application of SA at 2000 ppm concentration in 'Kensington' mangoes reduced the severity of anthracnose, but doses up to 1000 ppm were not very effective (Zainuri et al 2001).…”

“…The exogenous application of salicylic acid (SA), which is involved in the disease resistance in plants, has been demonstrated to be effective in enhancing the disease resistance in mango fruit (Zainuri et al 2001;Zeng et al 2006). The post-harvest application of SA at 2000 ppm concentration in 'Kensington' mangoes reduced the severity of anthracnose, but doses up to 1000 ppm were not very effective (Zainuri et al 2001). The vacuum infiltration of 1 mmoll −1 SA in 'Matisu' mango also enhanced the disease resistance against anthracnose by increasing the activities of phenylalanine ammonia lyase (PAL) and b-1,3-glucanase in SA-treated fruit (Zeng et al 2006).…”