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纹枯病菌絲在田間稻株上的消长受水稻各生育期、及当时气候条件影响很大;一般在孕穗职前菌絲量少,孕穗至乳熟初期分布量大、蔓延速度快;抽穗期后10天达到最高峯。早稻成熟期菌絲停止蔓延或消失;晚稻(尤其連作晚稻)抽穗期后因寒潮或低温而停止蔓延;乳熟期趋于消失。纹枯病菌核的发育一般要通过四个时期,无休眠期。病情的水平扩展速度以孕穗至抽穗期最快,乳熟期几停止;而垂直扩展速度以水稻分蘖期最慢,抽穗至乳熟期最快。矮稈品种2—3天,高稈品种3—5天便可士升一个叶位,乳熟后緩慢。晚稻則以抽穗期最快,抽穗后緩慢,乳熟后病势停滞不前。在水稻易感期(孕穗—抽穗),遇到梅雨的两端低温,职及矮稈品种、多肥、密植,在一定有效菌核量下,是本病流行期、流行程度的关鍵因素。防治适期应以菌絲蔓延前期,卽在分蘖期至孕穗期施药,以杀伤菌絲为主;有必要时可在抽穗期再施药一次,保护剑叶,以抑制菌核形成、兼杀菌絲为主。如对矮稈品种、多肥栽培的水稻,于分蘖期施药保护是很必要的。
Rhizoctonia solani in the field of paddy rice growth and decline by the rice growth period, and the climatic conditions have a great impact; generally in the booting pre-job hyphae less, booting to the beginning of the milk during the early distribution of large, rapid spread; heading After 10 days to reach the peak. Mycelium of mature rice at the early stage stopped or disappeared. Late rice (especially late rice) stopped spreading due to cold or low temperature after heading stage, and milky milky stage tended to disappear. Rhizoctonia solani nuclear development generally through four periods, no dormancy. The level of disease spread to the fastest booting to heading, milking a few stops; while the vertical expansion of rice tillering the slowest, heading to the millet fastest. Dwarf varieties 2-3 days, 3-5 days tall stalks will be able to increase a leaf position, milk slowly. Late rice is the fastest heading, heading slowly, milk disease after the stagnation. In the susceptible period of rice (booting - heading), both ends of the rainy season encountered low temperature, professional and dwarf varieties, more fat, close planting, in a certain amount of effective bacteria, is the epidemic, the key factor in the prevalence . Control should be premature mycelium spread, 卽 in the tillering stage to booting stage to kill mycelium-based; if necessary, can be applied again at heading to protect the flag leaf to inhibit the formation of sclerotium Sterile silk-based. Such as dwarf varieties, fertile cultivation of rice, tillering pesticide application is necessary.