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Light influences important physiological and morphological responses in fungi, hence they can sense near UV, blue, green, red and far-red lights using up to eleven (11) photoreceptors and signaling cascades to control a larger proportion of the genomes and adapt to environmental factors. Though light is an environmental signal regulating myriad of biological processes, fungi do not utilize it as a source of energy for synthesis of food but for information and other developmental processes. Two genes WC-1 and WC-2 have been identified to function as photoreceptor for blue light proteins or orthologs and transcription factor for other light induced phenomenon. Additionally, conserved WCC photoreceptor orthologs (FaWC1 and FaWC2) may also perform divergent roles in some fungal species such as light signals to regulate UV resistance, secondary metabolism and sexual reproduction as well as for virulent expression. Response to white light irradiation has also elicited different morphological and physiological changes in various species of fungi such as asexual reproduction and induction or inhibition of several developmental processes. Mushrooms also requires light for developmental processes such as the asexual stage for completion of its life cycle whereas it is unnecessary at the vegetative stage. This review provides some recent crucial impact of light irradiation on the developmental processes of fungi such as sporogenesis, germination/conidiation, reproductive development, pathogenesis, mycotoxin and mushroom development even though they are generally known to be achlorophyllous and non-photosynthetic. Thus, identifying conditions of light regime that will favour fungal development with reduced mycotoxin production will be beneficial to animals and human health. Additionally, developing new techniques to control fungal species may lead to the development of faster and more effective food-processing methods.

Tomato (Solanum lycopersicum) is one of the most economically attractive and widely consumed vegetables globally. Their high water content, perishability, transport and poor storage system predisposes them to spoilage by a broad spectrum of mycoflora resulting in huge postharvest losses. This study investigates antimycotic potential of alum on postharvest deterioration of tomato. Composite samples of deteriorating tomatoes were subjected to standard mycological analysis from which total fungal colony counts obtained ranged from 1.64x106-5.70x109 CFU/g, and the following species were identified; Aspergillus niger, A. flavus, Fusarium sp, Penicillium sp, Rhizopus stolonifer, Geotrichum candidium and Saccharomyces cerevisiae. In vitro antimycotic activity of alum (1% (w/v) concentration) was determined on some of the isolates by agar well method (AWM) and diameter of inhibition zone (DIZ) measured using a metre rule. G. candidum had the highest DIZ (9.0mm (29.0%) followed by A. niger (8.0 mm (25.8%) and 7.0mm (⁓ 22.6%) for Fusarium and Penicillium species respectively. R. stolonifer showed no inhibition or zero. pH values increased from 4.35-4.52 whereas TTA values decreased from 0.13-0.07 within 2days of analysis. However, these results indicate that treatment of postharvest deteriorating tomatoes with alum prior to consumption would enhance food safety as some of these fungi are known to be spoilage, toxigenic or opportunistic pathogens. So, their presence raises concern on storability as well as public health risks associated with consumption of these fruits. Therefore, production of tomato requires an integrated and multidisciplinary research approach not only to reduce economic loss but also create consumers’ awareness on potential public health hazards of consuming relatively cheaper and pathogen contaminated deteriorating tomatoes.