玉米穗轴对穗腐病抗性鉴定体系与优异抗源的研究

穗轴作为拟轮枝镰孢菌侵染果穗引发玉米穗腐病的重要途径之一，能够影响病原菌的侵染和扩散。为了深入开展玉米穗轴对拟轮枝镰孢菌抗性的研究以及了解玉米穗腐病子粒与穗轴抗性的差异，进行抗性鉴定体系的优化，利用164份国内外玉米骨干自交系进行两年两点的接种鉴定筛选优异抗源，对发病边长、发病芯长、发病面积、发病相对面积等4个抗性指标进行研究。结果表明，发病边长能较大程度地区分不同自交系间的抗感差异且又在材料内具有较好的重演性。把发病边长确定为玉米穗腐病穗轴抗性鉴定指标，对参试自交系进行抗性评价，鉴定出CML27、BT-1、CML274等58份穗轴高抗自交系，筛选出BT-1、CML173、CML193等8份子粒与穗轴均抗穗腐病的优异抗源。

Study on Cob Inoculation System and Elite Resistant Inbred Lines Screened to Maize Ear Rot

As an important pathway, cob can affect the infection and spread of Fusarium verticillioide in maize ear. In order to study the cob resistance to Fusarium verticillioide and to understand the difference between kernel resistance and cob resistance in maize, the identification system of cob resistance was optimized. In addition, 164 inbred lines were surveyed to establish the cob resistance identification system and to select excellent resistance inbred lines in two years and two locations. By analyzed of the four indexes(surrounding infected length, internal infected length, infected area and relative infected area), the surrounding infected length was identified as optimal, which has better repeatability in same inbred line and can easier distinguish the resistance between different inbred lines. Fifty-eight inbred lines with high resistance of cob were identified, such as CML27, BT-1, CML274, etc. At the same time, elite inbred lines BT-1, CML173, CML193 and other eight inbred lines with high resistance to ear rot in both kernel and cob were screened out. These results laid a foundation for disease resistance breeding and resistance inheritance research.