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粟瘟(Piricularia setariae Nishikado)是关內外、魯西一带谷子上常見的病害,严重时引起苗枯、叶瘟、頸瘟,損失极大。种子及谷草带病是苗期粟瘟的主要侵染来源。經过种子处理者(温湯浸种,0.3%西力生拌种)发病率較未处理者減輕14—62%。野生寄主侵染来源作用还不明瞭。不同品种間对粟瘟的抗病性不同。苗期、抽穗期均感病者有磨里、华农四号;苗期、抽穗期均抗病者有三三二、金綫子;苗期較抽穗期病輕者有小黃谷、白母鸡咀、二三一;抽穗期較苗期病輕者有大白谷、六一一、鉄头碰。早播(4月17—22日)較晚播(4月24—27日)者发病重,但早播結合种子处理較晚播不处理者病輕。不施硫胺种肥者較施用不同量种肥的苗期发病率低,但到抽穗前后差别漸消失。高度密植(每亩6万株)的比一般密度(每亩3万株)病情指数增加50%以上。田間相对露量与病情指数一致。密植田6万株的比一般田3万株的在苗期露量增高20%,抽穗期增高26%以上,但两者抽穗期間露量均比苗期为高。密植田增高23%,一般田增高14.7%。在17个品种观察中,1959年粟瘟病出現二个高峯,第一个高峯在苗期2—3片真叶开始,5月17日前,这时普遍发病,病株率在10—67%左右,以后病势停止发展,随着植株的不断生长,新叶抽出,老叶病叶枯死,到6月1日左右病情指数显著下降,到抽穗期病情指数又普遍上升,出現第二个发病高峯。在定点定株田間小气候观察中,可見5月下旬至6月3日前气温为24—25℃,相对湿度不足60%,有风无露,病害停止发展,病情指数下降。6月4日后有阴雨,两天內降雨量为20毫米,气温平均为19%,相对湿度达到85%,夜間无风有露,病情指数上升。6月10日后連續干旱,气温在27℃,相对湿度在49%,半月内仅4天有露量,植株下部叶片干枯,病情指数下降。6月26日后有阴雨,露量增加,平均气溫25.5℃,相对湿度为75%,病害連續发展。根据上述研究对生产上防治粟瘟提出如下建議:(1) 結合消灭白髮病、粒黑穗病,严格实行种子处理。尤其早播地区,种子处理以溫湯浸种較好,0.3%賽力散拌种較差。(2) 合理密植,以每亩3—4万株为宜。过密生长不良,病害严重。(3) 谷子收获后,及时清除田間杂草、谷草,勿堆置田間,以減少初次侵染来源。在发病严重地区,可选用抗病品种,如三三二、鉄头碰等。
Piricularia setariae Nishikado is a common disease on the millet in the Luxi area, both inside and outside the country. In severe cases, it causes seedling blight, leaf blast and neck blast, resulting in great losses. Seeds and asparagus disease is the main source of infection of seedling stage. After seed treatment (warm soaking, 0.3% silage seed dressing) incidence of 14-62% reduction compared with the untreated. The role of wild host infection source is unclear. Different varieties of different resistance to the blast disease. At the seedling stage and heading stage, all the susceptible patients were grinded and weinong No.4. In the seedling stage and heading stage, all the disease-resistant ones had three or three and golden thread. The seedlings had smaller yellow valley and white mother Chicken Tsui, two hundred thirty-one; heading stage than the seedling disease light large white valley, six one eleven, Yu head touch. Early sowing (April 17-22) later sowing (April 24-27) were severely ill, but early sowing combined with seed treatment later sowing did not deal with the disease is light. No application of thiamine fertilizer than the application of different amounts of fertilizer seedling incidence of low, but before and after heading gradually disappear. The density index (60 000 plants per acre) increased by more than 50% over the normal density (30000 plants per acre). The relative field exposure consistent with the disease index. The density of 60000 plants in the densely populated fields was 20% higher than that in the normal fields and more than 26% in the heading stages. However, the exposed amount during the heading stage was higher than that in the seedling stage. Close planting fields increased by 23%, generally increased by 14.7% field. In 17 varieties of observation, 1959 blast appeared two peaks, the first peak 2-3 seedlings true leaves begin, May 17, when the general incidence of diseased plants at about 10-67% After the disease ceased to develop, with the continuous growth of plants, the new leaves were taken out and the leaves of the old leaf blight dead. By June 1, the disease index dropped significantly, and the disease index rose to the peak at the heading stage. In the fixed-point field microclimate observation, it can be seen from the end of May to June 3 before the temperature of 24-25 ℃, relative humidity less than 60%, wind without dew, the disease stopped the development, the disease index decreased. There was overcast after June 4, with a rainfall of 20 millimeters in two days, an average temperature of 19% and a relative humidity of 85%. During the night, there was no wind and rain and the disease index rose. Continuous drought after June 10, the temperature at 27 ℃, relative humidity of 49%, only half a month exposed, the lower leaves of plants dry, the disease index decreased. After June 26, there is overcast and rainy season with the increase of dew amount. The average temperature is 25.5 ℃ and the relative humidity is 75%. The disease continues to develop. According to the above research on the production of prevention and treatment of blast disease made the following recommendations: (1) combined with the elimination of white hair disease, smut, strict implementation of seed treatment. Especially in the early sowing area, seed soaking with warm soup is better, and 0.3% saioli is poor. (2) reasonable close planting, with 3-4 million per mu is appropriate. Over-dense growth, serious disease. (3) millet harvest, the timely removal of field weeds, straw, do not stack the field to reduce the source of the initial infection. Severe areas in the disease, the choice of disease-resistant varieties, such as three three two, 鉄 Tou touch.