Abstract
Silks are the long threads at the tips of maize ears onto which pollen land and sperm nuclei travel long distances to fertilize egg cells, giving rise to embryos and seeds; however fungal pathogens also use this route to invade developing grain, causing damaging ear rots with dangerous mycotoxins. This review highlights the importance of silks as the direct highways by which globally important fungal pathogens enter maize kernels. First, the most important silk-entering fungal pathogens in maize are reviewed, including Fusarium graminearum, Fusarium verticillioides, and Aspergillus flavus, and their mycotoxins. Next, we compare the different modes used by each fungal pathogen to invade the silks, including susceptible time intervals and the effects of pollination. Innate silk defences and current strategies to protect silks from ear rot pathogens are reviewed, and future protective strategies and silk-based research are proposed. There is a particular gap in knowledge of how to improve silk health and defences around the time of pollination, and a need for protective silk sprays or other technologies. It is hoped that this review will stimulate innovations in breeding, inputs, and techniques to help growers protect silks, which are expected to become more vulnerable to pathogens due to climate change.
Highlights
Maize (Zea mays ssp. mays) is a staple crop used around the globe for food, animal feed, biofuel, and bioproducts [1]
Devastating ear rot fungi have a common feature—they enter via the style, which in maize is a thread-like channel called silk (Figure1)
A. flavus does not often infect the cob pith [54], like F. graminearum, A. flavus can travel through the cob to infect other kernels [57], and silk infection can lead to greater consequences
Summary
Maize (Zea mays ssp. mays) is a staple crop used around the globe for food, animal feed, biofuel, and bioproducts [1]. Fiscal challenge leads to inadequate storage infrastructure and a lack of affordable, validated mycotoxin testing, and the high humidity and temperatures in the tropics further create an advantageous habitat for toxigenic fungi [6,7] This leads to mycotoxins in food and feed. Pathogens 2018, 7, x FOR PEER REVIEW devastating ear rot fungi have a common feature—they enter via the style, which in maize is a thread-like channel called silk (Figure). Ancient farmers in Mexico selected for large cobs surrounded by protective husk leaves, husk leaves, under which silks must grow and emerge [13]. The purpose of this review is to highlight the importance of the silk channel as the direct highway by which globally important fungal pathogens enter maize kernels. (1) to review the most important silk-entering fungal pathogens in maize; (2) to compare the modes that fungal pathogens use to invade the silk route; (3) to review the innate silk defence system and current strategies for fighting silk-entering fungi in order to (4) direct future research and lead to targeted strategies to help growers protect silks
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
