不同施氮方式对黑龙江省水稻主栽品种稻瘟病发生的影响

通过不同施氮方式对黑龙江省主栽品种稻瘟病的研究,探讨了施用氮肥对稻瘟病发病规律的影响。试验结果表明:稻瘟病的发生氮肥起着决定性作用,N肥高、中、低及0氮肥条件下,叶瘟和穗颈瘟的发病规律呈现出相同的趋势,随着N肥量的增多发病率增强,病情严重;不同的施肥方式叶瘟和穗颈瘟也呈现出相同的规律,基蘖肥与穗粒肥比为7:3发病率与病情指数最高,发病最严重,基蘖肥与穗粒肥比为8:2、6:4表现病情相对较低。随着密度的降低,各品种发病情况无规律性。

The Effects of Different Nitrogen Applications on the Occurrence of Rice Blast on Main Cultivar Rice in Heilongjiang Province

The effects of different nitrogen applications on the occurrence of rice blast on main rice cultivar had been researched to explore the rules on the occurrence regularity of rice blast based on nitrogen applications. Results indicated that nitrogen fertilizer has decisive effect on the occurrence of rice blast. There are the similar occurrence regularities on both leaf blast and neck blast when fertilized with nitrogen of high content, medium content, low content and zero content. Incidences of the diseases are increasing and the diseases are more severe when fertilized with more nitrogen. Furthermore, there are the similar occurrence regularity on both leaf blast and neck blast when the nitrogen is fertilized by different methods, the incidences of the diseases and the disease indices are the highest when the ratio of fertilizer for tillering and fertilizer for spikes is 7：3. The incidences of diseases are less severe when the ratios of fertilizer for tillering and fertilizer for spikes are 8：2 and 6：4. There are no remarkable rules in the occurrence of diseases in different cultivars when the planting density is decreasing.