Aflatoxin contamination is common in several crops, including maize, in warm agricultural areas. For over 40 years, there have been many efforts to develop maize germplasm with resistance to aflatoxin contamination produced by Aspergillus flavus Link:Fr. In Mexico, there are native maize landraces (MLRs) with superior resistance to both aflatoxin contamination and kernel rot by A. flavus. Resistance mechanisms for some MLRs have been characterized. We investigated whether MLRs vary in susceptibility to multiple members of several aflatoxin-producing species and if resistance is affected by length of the infection period. Results indicate significant differences (P < 0.05) in abilities to produce aflatoxin within and among aflatoxin-producing fungi in two MLRs during two infection periods. There were also significant (P < 0.05) differences among several MLRs and a commercial hybrid control to both aflatoxin accumulation and kernel rot in laboratory assays over a 25-day period. The current results suggest breeding for aflatoxin resistance in maize should include several variables. To be broadly useful, commercially acceptable resistant maize germplasm must be resistant to diverse aflatoxin-producing species over time frames and under conditions the maize is exposed to both in the field and during storage.

黄曲霉毒素污染在温暖农业区的几种作物中很常见，包括玉米。在过去的40年中，出现了很多努力发展同所产生黄曲霉毒素污染性玉米种质黄曲霉链接：FR。在墨西哥，有天然玉米地方品种（混合淋巴细胞反应）与既黄曲霉毒素污染和内核腐优越的抗由黄曲霉。一些 MLR 的耐药机制已被表征。我们调查了 MLR 对几种产黄曲霉毒素物种的多个成员的易感性是否不同，以及耐药性是否受感染期的长短影响。结果表明存在显着差异（P < 0.05) 在两个感染期间，在两个 MLR 中产生黄曲霉毒素的真菌内部和之间产生黄曲霉毒素的能力。在 25 天的实验室测定中，几种 MLR 和商业杂交对照对黄曲霉毒素积累和籽粒腐烂也存在显着差异（P < 0.05）。目前的结果表明，玉米黄曲霉毒素抗性育种应包括几个变量。为了广泛使用，商业上可接受的抗性玉米种质必须在一段时间内和在玉米在田间和储存期间暴露的条件下对不同的黄曲霉毒素产生物种具有抗性。