Brazilian Journal of Biological Sciences (ISSN 2358-2731)



Home Archive v. 5, no. 10 (2018) Oladele

 

Vol. 5, No. 10, p. 619-626 - Aug. 31, 2018

 

Control of Rhizopus: Induced decay in watermelon (Citrullus lanatus L.) fruits using heat treatment



Oladele Oluwole Olakunle

Abstract
Control of Rhizopus, induced decay in watermelon (Citrullus lanatus) fruits using heat treatment was investigated. Watermelon fruits of uniform size and colour were selected, washed with clean water and disinfected after harvest. The fruits were then inoculated with spore suspension containing 3.02 x 103 spores mL-1 of Rhizopus sp. inoculated fruits were immersed separately in a water bath at 50 oC for 2, 3 and 5 min and 53 oC for 2 and 3 min. Control fruits were inoculated but not heat treated. Each set up was in 3 replicates. Control and treated fruits were then stored in cleaned transparent plastic containers at 28 oC + 2 oC and 75%-80% relative humidity and observed daily for disease severity. Result obtained on day 5 of storage showed there was no significance difference (p > 0.05) in the disease severities of control and all the treated fruits. The disease severity of both the control and all treated fruits was 1.00 + 0.28 which implied that the fruits were healthy (disease free). However as storage period progressed to day 25, only fruits treated at 53 oC for 3 min maintained disease severity of 1.00 + 0.00, which implied that the fruits were still disease free, recording mean appearance and taste index of 3.50 and 2.00, respectively, which thus indicated good appearance and sweet taste of the fruits. Other treatments recorded various degrees of rottenness. Hence, treatment at 53 oC for 3 min could be considered as the most effective for extending the shelf life of water melon fruits among all temperatures and time combinations experimented in the study.


Keywords
Disease severity; Hot water; Time; Pathogen; Spore suspension; Storage.

DOI
10.21472/bjbs.051035

Full text
PDF

References
Aborisade, A. T.; Akomolafe, O. M. Effect of heat treament of plaintain (Musa paradisiaca) from peel characteristics and control of decay by Fusarium verticilliodes. Asian Journal of Plant Science, v. 6, p. 523-527, 2007.

Aborisade, A. T.; Ojo, F. H. Effect of post-harvest hot air treatment of tomatoes (Lycopersicun esculentum) on storage life and decay caused by Rhizopus stolonifer. Journal of Plant Disease and Protection, v. 109, p. 639-645, 2002.

Arekemase, M. O.; Oyeyiola, G. P. Fungi associated with spoiled citrus fruits obtained from llorin. Centre Point (Science Edition), v. 4, p. 138-149, 2007.

Alexopoulous, C. J.; Mims, C. W.; Blackwell, M. Introductory Mycology. New York: John Wiley and Sons, 1996.

Babarinsa, F. A.; Williams, J. O. Control of weight loss in Valencia oranges using Waxed Paper Wrappers. Postharvest Science, v. 1, p. 78-80, 2002.

Barkai-Golan, R.; Phillips, D. J. Postharvest heat treatments of fresh fruits and vegetables for decay control. Journal of Plant Disease, v. 75, p. 1085-1089, 1991.

De Costa, D. M.; Erabadupitya, H. R. An integrated method to control postharvest diseases of banana using a member of the Burkhoderia cepacia Complex. Postharvest Biology Technology, v. 36, p. 31-39, 2005.

Fallik, E.; Klein, J.; Grinberg, S.; Gambourg, M.; Klein, J. D.; Lurie, S. Prestorage heat treatment reduces pathogenicity of Penicillium expansum in apple fruit. Journal of Plant Pathology, v. 45, p. 92-97, 2003.

Holmes, G. L.; Eckert, J. W. Sensitivity of Penicillium digitatum and P. italicum to post harvest citrus fungides in California. Phytopathology, v. 89, p. 716-721, 1999.

Jacobi, K. K.; Giles, J. E. Quality of 'Kesington' mango (Mangifera indica Linn.) fruit following combined vapour heat disinfestations and hot water disease control treatments. Postharvest Biology Technology, v. 12, p. 285-292, 1997.

Lamond, E. Laboratory method of sensory evaluation of foods. Canada: Canada Central Experimental Station, 1997.

Lluis, P.; Joseph, L. S.; Joseph, U.; Immaculada, V. Control of post-harvest blue and green molds of oranges by hot water, sodium carbonate, and sodium bicarbonate. Journal of Plant Disease, v. 85, p. 371-376, 2001.

Lurie, S. Post harvest heat treatment review. Postharvest Biology Technology, v. 14, p. 257-269, 1998.

Perkins-Veazie, A. U.; Yamaguchi, E. P. World vegetables: Principles, production and nutritive value. 2. ed. New Yoork: Chapman and Hall, 2001.

Smilanick, J. L.; Sorenson, D.; Mansoir, M.; Aieyabei, J.; Plaza, P. Impact of a brief post-harvest hot water drench treatment on decay, fruit appearance and microbial populations of lemons and oranges. Horticulural Technology, v. 13, p. 333-338, 2003.