Mesterhazy Akos
Cereal Research Non-Profit Ltd., Alsokikotosor 9, 6726 Szeged, Hungary.
J Fungi (Basel). 2024 Jan 4;10(1):40. doi: 10.3390/jof10010040.
Maize is the crop which is most commonly exposed to toxigenic fungi that produce many toxins that are harmful to humans and animals alike. Preharvest grain yield loss, preharvest toxin contamination (at harvest), and storage loss are estimated to be between 220 and 265 million metric tons. In the past ten years, the preharvest mycotoxin damage was stable or increased mainly in aflatoxin and fumonisins. The presence of multiple toxins is characteristic. The few breeding programs concentrate on one of the three main toxigenic fungi. About 90% of the experiments except AFB1 rarely test toxin contamination. As disease resistance and resistance to toxin contamination often differ in regard to , , and and their toxins, it is not possible to make a food safety evaluation according to symptom severity alone. The inheritance of the resistance is polygenic, often mixed with epistatic and additive effects, but only a minor part of their phenotypic variation can be explained. All tests are made by a single inoculum (pure isolate or mixture). Genotype ranking differs between isolates and according to aggressiveness level; therefore, the reliability of such resistance data is often problematic. Silk channel inoculation often causes lower ear rot severity than we find in kernel resistance tests. These explain the slow progress and raise skepticism towards resistance breeding. On the other hand, during genetic research, several effective putative resistance genes were identified, and some overlapped with known QTLs. QTLs were identified as securing specific or general resistance to different toxicogenic species. Hybrids were identified with good disease and toxin resistance to the three toxigenic species. Resistance and toxin differences were often tenfold or higher, allowing for the introduction of the resistance and resistance to toxin accumulation tests in the variety testing and the evaluation of the food safety risks of the hybrids within 2-3 years. Beyond this, resistance breeding programs and genetic investigations (QTL-analyses, GWAM tests, etc.) can be improved. All other research may use it with success, where artificial inoculation is necessary. The multi-toxin data reveal more toxins than we can treat now. Their control is not solved. As limits for nonregulated toxins can be introduced, or the existing regulations can be made to be stricter, the research should start. We should mention that a higher resistance to and can be very useful to balance the detrimental effect of hotter and dryer seasons on aflatoxin and fumonisin contamination. This is a new aspect to secure food and feed safety under otherwise damaging climatic conditions. The more resistant hybrids are to the three main agents, the more likely we are to reduce the toxin losses mentioned by about 50% or higher.
玉米是最常受到产毒真菌侵害的作物，这些真菌会产生多种对人类和动物都有害的毒素。收获前的谷物产量损失、收获前的毒素污染（收获时）以及储存损失估计在2.2亿至2.65亿吨之间。在过去十年中，收获前的霉菌毒素损害保持稳定或有所增加，主要集中在黄曲霉毒素和伏马菌素方面。多种毒素并存是其特点。少数育种项目仅专注于三种主要产毒真菌中的一种。除黄曲霉毒素B1外，约90%的实验很少检测毒素污染情况。由于抗病性和抗毒素污染能力在、和以及它们所产生的毒素方面往往存在差异，仅根据症状严重程度无法进行食品安全评估。抗性的遗传是多基因的，常伴有上位效应和加性效应，但只能解释其表型变异的一小部分。所有测试均使用单一接种物（纯分离株或混合物）。不同分离株以及根据侵染力水平的基因型排名有所不同；因此，此类抗性数据的可靠性往往存在问题。花丝通道接种通常导致的穗腐严重程度低于籽粒抗性测试中的情况。这些因素解释了进展缓慢的原因，并引发了人们对抗性育种的质疑。另一方面，在基因研究过程中，已鉴定出多个有效的假定抗性基因，其中一些与已知的数量性状位点（QTL）重叠。已确定QTL可确保对不同产毒物种具有特异性或一般性抗性。已鉴定出对三种产毒物种具有良好抗病性和抗毒素能力的杂交种。抗性和毒素差异通常达十倍或更高，这使得在品种测试中引入抗性和抗毒素积累测试，并在2至3年内评估杂交种的食品安全风险成为可能。除此之外，抗性育种项目和基因研究（QTL分析、全基因组关联研究测试等）也可以得到改进。在需要进行人工接种的所有其他研究中都可以成功应用。多种毒素的数据显示出比我们目前所能处理的更多的毒素。它们的控制问题尚未解决。由于可以引入对未受监管毒素的限量标准，或者使现有法规更加严格，因此相关研究应该启动。我们应该提到，对和具有更高的抗性对于平衡炎热干燥季节对黄曲霉毒素和伏马菌素污染的不利影响非常有用。这是在其他方面具有破坏性的气候条件下确保食品和饲料安全的一个新方面。杂交种对三种主要病原体的抗性越强，我们就越有可能将上述毒素损失降低约50%或更多。
