Effect of grain coverage disruption on aflatoxins in maize and sorghum

Abstract

Aflatoxins are dangerous mycotoxins in crop production, demonstrated to reduce crop quality and value through both pre-and post-harvest contamination. Aflatoxin contamination is encountered much more frequently in maize (Zea mays L.) than its close relative sorghum [Sorghum bicolor (L.) Moench]. This study focused on evaluating the effect of grain coverage on aflatoxin accumulation in both crops; comparing coverage of the female inflorescence (exposed sorghum grain vs. husk covered maize grain) as well as the impact of paper bag coverage during pollination activities. The maize and sorghum female inflorescence were further manipulated by either decreasing or increasing the grain coverage. Two specific hypotheses were statistically tested for aflatoxin accumulation in grain from inoculated inflorescences: aflatoxin accumulation changes in maize and sorghum inflorescences when they are modified from their natural state, and aflatoxin accumulation varies between natural and artificial covering of inflorescences. Aflatoxin data collected from 2 yr of inoculating Aspergillus flavus into maize ears and sorghum panicles indicated that modifying the inflorescences of both species had the largest effects in increasing aflatoxin amounts. Substituting natural coverage of maize and bagging sorghum panicles increased aflatoxin accumulation significantly. This study demonstrated that sorghum may accumulate substantial aflatoxins when it is inoculated and the inflorescence is modified by covering with a paper pollinating bag. Substituting maize husks with paper pollinating bags also substantially increased aflatoxin accumulation in maize. INTRODUCTIONAflatoxins are carcinogenic mycotoxins produced by Aspergillus spp. fungi that infect numerous crops both preand post-harvest. Aspergillus flavus infects maize (Zea mays L.), sorghum [Sorghum bicolor (L.) Moench], rice (Oryza sativa L.), cottonseed (Gossypium spp.), and peanutThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Apigeninidin-rich Sorghum bicolor (L. Moench) extracts suppress A549 cells proliferation and ameliorate toxicity of aflatoxin B1-mediated liver and kidney derangement in rats

“…Given that S. bicolor is less susceptible to aflatoxin contamination in the field 37 , 38 , we next probed further for the effects of SBE-05, SBE-06 and SBE-07 on the hepatorenal system of male Wistar rats challenged with AFB 1 . Specifically, we measured the effect of SBEs on organosomatic indices of rats, including mean body weights, organ weights and relative organ weights of the liver and kidney.…”

“…Extracts from maize 31 , Piper beetle 32 , and Heracleum persicum , Peganum harmala , and Trachyspermum ammi 33 , have been shown to inhibit AFB 1 biosynthesis and A. flavus growth. Sorghum bicolor plant has a high abundance of 3-deoxyanthocyanins, flavonoids and other polyphenol compounds that elicit phytoalexin activity 34 – 36 , and it is less susceptible to aflatoxin contamination in the field 37 , 38 . However, sorghum grains are frequently contaminated with aflatoxins at higher levels under storage 39 , 40 .…”