Hostname: page-component-7c8c6479df-p566r Total loading time: 0 Render date: 2024-03-19T04:51:55.007Z Has data issue: false hasContentIssue false

Evaluation of Ethiopian plant extracts, Acacia seyal and Withania somnifera, to control green mould and ensure quality maintenance of citrus (Citrus sinensis L.)

Published online by Cambridge University Press:  23 October 2009

Sissay B. Mekbib
Affiliation:
Postharvest Technol. Group, Dep. Microbiol. Plant Pathol., Univ. Pretoria, Pretoria, 0002, South Africa
Thierry J.C. Regnier
Affiliation:
Postharvest Technol. Group, Dep. Microbiol. Plant Pathol., Univ. Pretoria, Pretoria, 0002, South Africa Present address: Dep. Chem., Tshwane Univ. Technol., PO Box 56208, Arcadia Pretoria 0001, South Africa
Dharini Sivakumar
Affiliation:
Postharvest Technol. Group, Dep. Microbiol. Plant Pathol., Univ. Pretoria, Pretoria, 0002, South Africa
Lise Korsten
Affiliation:
Postharvest Technol. Group, Dep. Microbiol. Plant Pathol., Univ. Pretoria, Pretoria, 0002, South Africa
Get access

Abstract

Introduction. Green mould, Penicillium digitatum (Pers.: Fr.) Sacc., causes economically important postharvest disease in citrus. Materials and methods. Ethiopian plant extracts of Acacia seyal (Del. Var. Seyal) and Withania somnifera (L.) Dual were used to test the control of green mould in wound-inoculated fruit, stored for 21 d at 7 °C and at > 85% RH. The chemical compositions of the two extracts were determined using high-performance chromatography. Thereafter, freshly harvested (naturally infected) fruit were subjected to different postharvest treatments and stored for 50 d to investigate the effects of the two plant extracts on fruit quality parameters. Treatments included (pre-wax + leaf extracts), (wax + leaf extracts incorporated into wax, Citrosol A®), (leaf extract alone), (fruit washed in chlorinated water at 5.25%), (untreated fruit) and (commercially treated fruit). Results. Extracts of A. seyal and W. somnifera reduced the incidence of green mould by 56.1% and 50%, respectively, in wound-inoculated fruit. A. seyal extract contained a high concentration of gallic acid (60.3 mg·mL–1) whilst W. somnifera contained low concentrations of caffeic acid (8.7 mg·mL–1), salicylic acid (6.3 mg·mL–1) and 3,4 dihydroxy benzoic acid (3.8 mg·mL–1). Green mould was absent in naturally infected fruit subjected to (pre-wax + leaf extracts), (wax mixed with leaf extracts) and (leaf extracts) treatments. (Pre-wax + leaf extracts) and (wax mixed with leaf extract) treatments significantly reduced weight loss; retained firmness and colour; and they maintained eating qualities and a maturity index (SSC/TA) similar to commercial treatment. Conclusion. Both extracts of A. seyal and W. somnifera showed potential to be used as an alternative in combined applications with wax application under low temperature storage to replace synthetic fungicides, to ultimately control green mould and retain overall fruit quality.

Type
Research Article
Copyright
© CIRAD, EDP Sciences, 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Eckert J.W., Brown G.E., Evaluation of postharvest treatments for citrus fruits, in: Hickey K.D., Methods for evaluating pesticides for control of plant pathogens, Am. Phytopathol. Soc. Press, St.-Paul, MN, USA, 1986, pp. 92–97.
Snowdon A.L., Color atlas of post-harvest diseases and disorders of fruits and vegetables, Vol. 2., CRC Press, Boca Raton, Boston, USA, 1992.
Droby, S., Cohen, L., Daus, A., Weiss, B., Horev, B., Chalutz, E., Katz, H., Keren-Tzur, H., Shachnai, A., Commercial testing of aspire: a yeast preparation for the biological control of postharvest decay of citrus, Biol. Control 12 (1998) 97107. CrossRef
Bull, C.T., Wadsworth, M.L., Sorensen, K.N., Takemoto, J.Y., Austin, R.K., Smilanick, J.L., Syringomycin, E., Produced by biological control agents controls green mold on lemons, Biol. Control 12 (1998) 8995. CrossRef
Similanick, J.L., Mansour, M.F, Margosan, D., Mlikota Gabler, F., Goodwine, W.R., Influence of pH and NaHCO3 on the effectiveness of imazalil to inhibit germination of spores of Penicillium digitatum and to control citrus green mold on citrus fruit, Plant Dis. 89 (2005) 640648. CrossRef
Demissew S., Este debdabe: Ethiopian traditional medicine, Dep. Biol., Sci. Fac., Addis Ababa Univ., Ethiopia, 1989.
Bekele T.A., Useful trees of Ethiopia, RSCU, SIDA, Nairobi, Kenya, 1993.
Mekbib S.B., Identification of citrus (Citrus sinensis) postharvest pathogens from Ethiopia and their control, thesis, Univ. Pretoria, South Africa, 2007.
Saks, Y., Baraki-Golan, R., Aloe vera gel activity against plant pathogenic fungi, Postharvest Biol. Technol. 6 (1995) 159165. CrossRef
Yigit, F., Ozcan, M., Akgul, A., Inhibitory effect of some spice essential oils on Penicillium digitatum causing postharvest rot in citrus, Grasasy Aceites 51 (2000) 237240.
Palou, L., Marcilla, A., Rojas-Argudo, C., Alonso, M., Jacas, J.A., del Río, M.A., Effects of x-ray irradiation and sodium carbonate treatments on postharvest Penicillium decay and quality attributes of clementine mandarins, Postharvest Biol. Technol. 46 (2007) 252261. CrossRef
Sivakumar, D., Korsten, L., Influence of modified atmosphere packaging and postharvest treatments on quality retention of litchi ‘Mauritius’, Postharvest Biol. Technol. 41 (2006) 135142. CrossRef
Duke J.A., Medicinal plants of the Bible, Trado-Medic Books, Owerri, N. Y., USA, 1983.
Cowan, M.M., Plant products as antimicrobial agents, Clin. Microbiol. Rev. 12 (1999) 564582.
Rahman, A., Jamal, S.A., Choudhary, M.I., Asif, A., Two withanolides from Withania somnifera, Phytochem. 30 (1991) 38243826. CrossRef
Mhinzi, G.S., Intra-species variation of the properties of gum exudates from Acacia senegal var. senegal and Acacia seyal var. fistula from Tanzania, Bull. Chem. Soc. Ethiop. 17 (2003) 6774. CrossRef
Mekbib, S.B., Regnier, T.J.C., Korsten, L., Control of Penicillium digitatum on citrus fruit using two plant extracts and study of their mode of action, Phytoparasit. 35 (2007) 264276. CrossRef
Cheng, G.W., Breen, P.J., Activity of phenylalanine ammonia-lyase (PAL) and concentrations of anthocyanins and phenolics in developing strawberry fruit, J. Am. Soc. Hortic. Sci. 116 (1991) 865869.
Porat, R., Vinokur, V., Weiss, B., Cohen, L., Daus, A., Goldschmidt, E.E., Induction of resistance to Penicillium digitatum in grapefruit by b-aminobutyric acid, Eur. J. Plant Pathol. 109 (2003) 901907. CrossRef
Ben-Yehoshua S., Fishman S., Fang D., Rodov V., New development in modified atmosphere packaging and surface coating for fruits, in: Chang M., Champ B.R., Highley E., Johnson G.I. (Eds.), Postharvest handling of tropical fruit, ACIAR, Canberra, Aust., 1994, pp. 250–260.
Porat, R., Weiss, B., Cohen, L., Daus, A., Biton, A., Effects of polyethylene wax content and composition on taste, quality and emission of off-flavour volatiles in ‘Mor’ mandarins, Postharvest Biol. Technol. 38 (2005) 262268. CrossRef
Hagenmaier, R.D., Shaw, P.E., Gas permeability of fruit coating waxes, J. Am. Soc. Hortic. Sci. 117 (1992) 105109.