不同品种与播期和播种量对青贮玉米病害发生的影响

Effects of different varieties,sowing dates,andseeding rates on the diseases of silage maize

摘要:

在成都市大邑县韩场镇和眉山市洪雅县中保镇主要种植区种植青贮玉米(Zea mays),设置早播,中播和晚播3个播期,10个青贮玉米品种,以及5个播种密度等农业措施,研究其对青贮玉米锈病(Puccinia sorghi),小斑病(Bipolaris maydis)和大斑病(Exserohilum turcicum )的影响。结果表明:中播较晚播青贮玉米锈病,小斑病和大斑病的发病率分别降低43.3%,27.4%和28.2%;青贮玉米播种密度266.7株/hm2 下,各病害发病率降低至不足10%,甚至不发病;青贮玉米不同品种间锈病,小斑病和大斑病的发病率有显著差异(P <0.05),适宜的品种使青贮玉米锈病,小斑病和大斑病发病率分别降低6.2%~32.4%,4.5%~27.9%和8.0%~27.5%,病情指数分别降低1.9~28.1,1.9~28.1和3.9~25.7,试验表明适宜的提早播期、选择合适的品种、降低播种密度可降低青贮玉米病害的发生。

Abstract:

In the main planting regions of Zea mays Linn.,the town of Hanchang,Dayi county,Chengdu cityand the town of Zhongbao,Hongya county,Meishan city,we set three sowing dates for early,middle and late sowing,10 varieties of silage maize,and 5 seeding rates to study its effects on rust,small leaf spot,and large leafspot of silage maize.The results showed that the incidence in the middle sowing date of rust,small leaf spot andlarge leaf spot of silage maize decreased by 43.3%,27.4%,and 28.2% respectively comparised with that in thelate sowing date.Under the seeding density of 4 000 plant/a,all diseases incidence of silage maize reduced to lessthan 10%,even 0%.There were significant differences in the incidence of rust,small leaf spot,and large leafspot in different varieties of silage maize(P <0.05).The suitable variety can make the incidence of rust,smallleaf spot,and large leaf spot of silage maize decreased by 6.2%~32.4%,4.5%~27.9%,and 8.0%~27.5%,disease index decreased by 1.9~28.1,1.9~28.1,and 3.9~25.7 respectively.The results indicated that advancingsowing time,decreasing the seeding density appropriately and choosing suitable variety can reduce the occurrenceof diseases of silage maize.