1997—2006年研究了北京地区大棚和露地引进阿月浑子良种Kerman、Peters及对照新疆阿月浑子叶褐斑病的症状、病原菌、致病程度影响因子、防治措施和效果。结果表明:肉眼可见为叶正、背面的症状有褐色圆形或不规则的病斑,严重者成片叶色焦黄。病原菌除了已报道的尾孢属外还发现有交链孢属。感病主要条件是30℃以上的月均温和64%～70%的空气相对高湿度。病情与品种、树势及栽培条件有关:Kerman和Peters抗病性较强;树势健壮,叶片磷含量达1.7503g·kg-1且含有较多铜、硼的壮苗无病;栽植过密、叶面积指数7以上较易致病。采取预防为主严控灌水,保持土壤自然含水量在10%～20%。生长期空气相对湿度在60%以下较宜。通过栽植良种、合理密植、培育壮苗、药肥并施即0.5%(NH4)2HPO4、0.5%K2HPO4与0.2%多菌灵、0.2%退菌特(轮流喷施),每周各1次,用量0.5kg·m-2,可将病情指数控制在6%以下。
This paper reported the symptoms, pathogen and pathogenic mechanism of the leaf brown spot and its control methods and their effects for the improved varieties Kerman and Peters of Pistacia vera introduced in 1997—2006 in contrast with Xinjiang Pistacia vera. The result showed that during disease occurrence, macroscopic, brown, circular or irregular lesion on both surface of the leaf occurred, and in severe cases leaves became massive scorch and yellow. According to the isolates from infected leaves, its pathogen has been verified to be fungi of Alternaria sp. And Cerospora sp. Monthly average temperature above 30℃ and air relative humidity 64%～70% accelerated occurrence and development of this disease. Disease severity was relevant to tree vigor and growth conditions. The cultivars Kerman and Peters showed higher resistance. Usually, trees which grow stronger and in soils rich in P (1.750 3 g·kg-1), and containing relatively high level of Cu and B didn‘t suffer from the disease. But planting in high-density with leaf area index (LAI) over 7, tree were prone to be infected. Based on studies on the disease, the authors summarize that control measures should be taken as major considerations for its effective; controlling irrigation strictly in accordance with soil natural water content(15%～20%) and air relative humidity (60%) at growth stages. Moreover, planting improved varieties with strong seedlings in reasonable density, and spraying once a week fungicides (0.2% carbendazim or 0.2% thiram in turn),and fertilizers(0.5%(NH4)2HPO4 or 0.5% K2HPO4), with dosage of 0.5 kg·m-2 can keep disease index below 6%.
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