Mycotoxins are very important in fruit infections but less explored. However, Technically speaking, fruit is a matured ovary, which contain seeds and other parts. In pre and postharvest diseases mycotoxins are everywhere in the soil where some of the commodities touched down to the soil, air, leaves, fruit itself, etc. It is sometimes infect fruits together with other pathogens, the very proof is when we isolate tissues from fruits many contaminants are mycotoxins included. It is very important but less regarded since many of plant pathologists focus on the pathogens responsible of for the necrotic infection published in literatures and not on mycotoxins as that usually called as contaminant in the process. Indeed, mycotoxins play vital roles in stored products.

@ Ngolong, the attached file may be useful to you.

As it is well explained by Jesryl Paulite, mycotoxins are the secondary metabolites produced by certain types of moulds (fungi) and usually referred as contaminants. The most common types of mold which are known to produce mycotoxins are Aspergillus, Penicillium, Fusarium, and Alternaria. To this regard, focusing on the root cause of the toxins in the fruits and other foodstuffs is really important and I don't think that pathologists are missing the role of mycotoxins in that way. Of course, due attention must be given to the mycotoxin producing fungi as they directly cause disease and death to humans and other animals.

Thanks @Tarafdar, @Jemal, and @Jesryl for your crucial contribution.

Can you tell more about the role of mycotoxin in the infection process of fruit ? Do Necrotic fungi need to produce mycotoxin to successfully infect fruits ? What is the contribution of mycotoxin in the infection process ?

Fungi produce numerous secondary metabolites (SMs) and numerous SM biosynthetic gene clusters have been annotated in fungal genomes. These gene clusters are often large, yet conserved across numerous fungal lineages, and thus presumed to provide evolutionary advantages. SM production likely evolved to inhibit other microbes competing for the same niches, deter mycophagous animals, infect hosts, etc. Mycotoxins are a subclass of SMs that cause dysfunction/toxicoses in animals. Phytotoxins are another subclass of SMs that cause dysfunction in plants. Some mycotoxins also affect plants and some phytotoxins also affect animals. Mycotoxins that can act as necrotrophic phytotoxins include DON and related trichothecenes in Fusarium, and fumonisins and AAL-toxin in Fusarium and Alternaria, respectively. I don't know if aflatoxins or ergot alkaloids have been shown to be required for plant pathogenesis. Of course there numerous other host-specific and -nonspecific phytotoxins produced by Fungi, but I believe the mycotoxicity of these are low-to-none or not investigated.

Hope this helps!

Thanks @Stephen, it is clear that mycotoxin can help necrotic fungi against its antagonists in the pathosystem. But are they for that essential to the infection process?