论文标题:玉米穗腐病串珠镰刀菌的生物学特性和玉米抗病性研究
Study on Biological Characteristics of Fusarium Moniliforme Related to Corn Ear Rot and Disease Resistance of Corn
论文作者
论文导师 文成敬,论文学位 硕士,论文专业 植物病理学
论文单位 四川农业大学,点击次数 132,论文页数 44页File Size2516K
2007-06-01论文网 http://www.lw23.com/lunwen_3668787/
Corn;; Corn ear rot;; Fusarium moniliforme;; Biological characters;; Resistance assessment
通过对2005年国家品种区试四川试点(雅安市多营农场)的51个玉米品系穗腐病的调查，结果表明，总的穗腐病发病率为23.2％，其中串珠镰刀菌性穗腐病占49.1％，是主要的玉米穗腐病。2006年8月，又对多营农场的不同遗传背景的12个玉米品系进行了调查，结果表明，总的穗腐病发病率为35.1％，其中串珠镰刀菌性穗腐病占77.1％，也是主要的玉米穗腐病。这两年的调查结果说明了串珠镰刀菌性穗腐病是玉米主要的穗腐病，串珠镰刀菌(Fmoniliforme)是主要的致病菌。 玉米收获时，从雅安市多营农场采集患有典型症状的串珠镰刀菌性穗腐病的果穗，用患病病籽粒分离得到病原物，经过鉴定，确定其为串珠镰刀菌(Fusarium moniliforme)，作为本实验的实验菌株，冰箱保存备用。 对串珠镰刀菌(F．moniliforme)生物学特性的比较研究表明：适合该病菌生长的条件是Czapek培养基和PDA培养基，温度范围是25℃～30℃，pH值是9，C源和N源分别是蔗糖，和KNO_3；适合该病菌产孢的条件是PSA培养基，温度范围是25℃～30℃，C源是蔗糖，N源是KNO_3，pH值是6；分生孢子的最佳萌发条件是25℃～30℃的温度范围，pH值是7，黑暗，光照对该病菌分生孢子萌发有明显的抑制作用。 对几种药剂对病菌生长和产孢量以及分生孢子萌发影响的研究表明，多菌灵、百菌清、三唑酮和甲基托布津这4种药剂对病菌生长和产孢以及分生孢子萌发的影响均不同。其中，甲基托布津对菌丝生长的抑制率在各个浓度下是最高的，对病菌产孢和分生孢子萌发的抑制也是很明显的，是几种药剂中抑制效果是最好的。另外，多菌灵和百菌清对病菌生长、产孢和分生孢子萌发的抑制效果也比较良好，都可以在生产中用来防治玉米穗腐病。 通过对串珠镰刀菌性穗腐病抗病性鉴定，结果表明：玉米穗腐病的接种方法以向苞叶内注射病菌孢子悬液的效果为好，这种接种方法接近自然，发病又比较充分；接种时期以乳熟期接种为最好，在这个时期接种，发病充分，易于数据统计分析；接种浓度以1×10~6个孢子／mL的孢子悬液为好；接种量为3mL孢子悬液／果穗。在抗病性鉴定方面，所鉴定的15份材料均为抗病材料，其中齐318和3411是高抗材料，病级和病情指数分别为0.17、3.3和0.43、8.6，可作为抗源利用。在本实验中所使用的接种技术和抗病性鉴定方法完全可以应用到抗病育种工作中去，为抗病育种提供了参考。 通过对抗、感品种接种病原菌后，其苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和超氧化物歧化酶(SOD)活性变化的研究表明，抗、感材料之间的变化大不相同，抗病材料中的各种酶活性变化都比较稳定，并且有活性波峰；而感病材料中各种酶活性变化都比较大，并且没有活性波峰。
The corn ear rot on 51 malze breeds which were made to national test in Sichuan was investigated in 2005.It showed that the rate of corn ear rot was 35.1%, corn ear rot by Fusarium moniliforme was one of the most important, which was counted for 49.1% in all rot ears investigated.In 2006, the corn ear rot on 12 maize breeds which have different genetic background was investigated again. The results showed that the rate of corn ear rot was 35.1%, what was caused by F.moniliforme was counted for 77.1% in total,and this was also the primary corn ear rot.The investigation of two years showed that corn ear rot by F.moniliforme was the dominant corn ear rot,and F.moniliforme was the major pathogen to corn ear rot. When the corn was harvested,the pathogen of the corn ear rot were isolated from diseased kernel in Duoying farm in Yaan, Sichuan.The pathogen was identified to be F.moniliforme.It was conserved in refrigerator to make further study. Study on biological characteristics of F.moniliforme showed that hyphae could grow well in the meadium of Czapek and PDA, at the condition of 25～30℃, pH9, carbom source and KNO_3.The optimum conditions for the sporulation were PSA medium, 25～30℃, pH6, carbom source and KNO_3. The optimum conditions for spore germination were 25～30℃,pH6 and darkness.The light could inhibit the spore germination obviously. Study on the effects of several fungicides on the hyphal growth and conidia production and germination rate of conidia showed that the four species fungicides which were carbendazim、chlororthalonil、triadimefon and topsin-M possesed different function.The inhibition ratios of hyphal growth were the highst under the each concentration of topsin-M.And it could inhibit conidia productin and germination rate of conidia obviously.So the efficiency of topsin-M in the lab was the best among the four fungicides, the effects of carbendazim and chiororthalonil were good,too.So they could be also used to control corn ear rot in practice. Study on disease resistance assessment of corn ear rot by F.moniliforme showed that the method of injection spore suspension into corn ear was the best inoculation method.This method is to be close to the natural condition, and the disease occures very sufficiently.The best inoculation time is milk stage.In this period, the disease occures very sufficiently and the data are statisticed very easily.The best inoculation concentration of spore suspension was 1×10~6 spores/mL,and the inoculation volume was 3mL/ear. The 15 breeds were tested for the resistance. It showed that the 15 breeds were disease resistance materials. Qi318 and 3411 were the high resistance materials. The disease severity and index were 0.17、3.3 and 0.43、8.6 respectively. This result showed that Qi318 and 3411 could be as resistance resource to use. The methods and technique used in this experiment could be used in the breeding for disease resistance. Study on the activity of PAL、POD and SOD in the corn after inoculated pathogen showed that there were big differences between resistance and susceptible materials. The changs were more stabilization in resistance materials than in susceptible materials. There is a wave crest of activities in resistance materials, but no activity wave crest in the susceptible.
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