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991.
苹果轮纹病菌对多菌灵的敏感性测定 总被引:10,自引:1,他引:10
2007年8-10月从山东主要苹果产区轮纹病果上分离获得83个苹果轮纹病菌(Botryosphaeria berengriana f.sp.piricola)菌株,采用菌丝生长速率法分别测定了各菌株对多菌灵的敏感性。结果表明,多菌灵对83个菌株的EC50值呈单峰频次分布,分布在0.0196~0.4867mg·L-1,均值为0.1080±0.0152mg·L-1;在83个菌株中选择对多菌灵最敏感的泰山海棠菌系进行重复测定,将其EC50平均值0.0428mg·L-1确定为苹果轮纹病菌对多菌灵的敏感基线;通过Duncan氏新复极差法和系统聚类分析结果表明,不同地理来源的苹果轮纹病菌对多菌灵的敏感性都处在较高水平,总体上不存在明显差异,没有出现敏感性下降的抗药性亚群体。 相似文献
992.
百合抗镰刀菌资源鉴定及抗病相关基因筛选 总被引:1,自引:0,他引:1
对20个百合种质资源的组培苗进行尖孢镰刀菌百合专化型(Fusarium oxysporum f. sp. lilii)室内接种鉴定;以筛选出有较好抗性的大花卷丹(Lilium leichtlinii var. maximowivzii Baker)为材料,以镰刀菌诱导12和24 h的作为处理组,无菌水处理作为对照组,采用SMART技术构建了百合经镰刀菌诱导后的抑制差减正、反向两个SSH文库。在正向文库中选择了4个抗病相关的ESTs,用半定量RT-PCR分析这些ESTs的表达情况。经接种鉴定,20个百合种质资源中,对百合镰刀菌表现高抗的有3个,中抗9个,感病8个;SSH文库ESTs片段大小为200 ~ 2 000 bp。依据斑点杂交结果,从正向SSH文库中挑取50个单克隆进行测序和比对分析,得到6种共10条抗病相关EST。通过半定量RT-PCR对其中的4条抗病相关ESTs:丝氨酸/苏氨酸蛋白激酶(serine/threonine protein kinase,S/TPK)、谷胱甘肽S–转移酶(glutathione S-transferase,GST)、过氧化物酶(peroxidase,POD)和亲环素(cyclophilin,CYP)的表达情况进行了分析,证明它们在一定程度上都受百合镰刀菌诱导而表现上调表达,推测其可能参与了百合对镰刀菌枯萎病的抗病过程。 相似文献
993.
侧耳属种间有性杂交研究 总被引:9,自引:4,他引:5
本试验对阿魏蘑和香平菇(本实验室培育的四倍体侧耳)进行种间有性杂交获得成功,在F2代中出现广泛的遗传分离,说明种间有性杂交可作食物用菌育种的有效手段,试验还探讨了阿魏蘑的起源问题。 相似文献
994.
R.P. Baayen M.G. Förch C. Waalwijk P.J.M. Bonants H.J.M. Löffler E.J.A. Roebroeck 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(9):887-894
Isolates of Fusarium oxysporum from lily were screened for pathogenicity, vegetative compatibility and DNA restriction fragment length polymorphisms, and compared to reference isolates of F. oxysporum f.sp. gladioli and F. oxysporum f.sp. tulipae to justify the distinction of F. oxysporum f.sp. lilii. Twenty-four isolates from different locations in The Netherlands (18 isolates), Italy (4 isolates), Poland and the United States (1 isolate each) shared unique RFLP patterns with probes D4 and pFOM7, while hybridization did not occur with a third probe (F9). Except for a self-incompatible isolate, these 24 isolates all belonged to a single vegetative compatibility group (VCG 0190). Isolates belonging to VCG 0190 were highly pathogenic to lily, but not to gladiolus or tulip, except for a single nonpathogenic isolate. Six saprophytic isolates of F. oxysporum from lily were nonpathogenic or only slightly aggressive to lily, gladiolus and tulip, belonged to unique VCGs and had distinct RFLP patterns. Three pathogenic isolates previously considered to belong to F. oxysporum f.sp. lilii were identified as F. proliferatum var. minus; all three belonged to the same VCG and shared unique RFLP patterns. These three isolates were moderately pathogenic to lily and nonpathogenic to gladiolus and tulip. The reference isolates of F. oxysporum f.sp. tulipae were pathogenic to tulip, but not to lily and gladiolus; they shared a distinct RFLP pattern, different from those encountered among pathogenic and saprophytic isolates from lily, and formed a separate new VCG (VCG 0230). Reference isolates of F. oxysporum f.sp. gladioli belonging to VCG 0340 proved pathogenic to both gladiolus and lily, but not to tulip. These isolates, as well as isolates belonging to VCGs 0341, 0342 and 0343 of F. oxysporum f.sp. gladioli, had RFLP patterns different from those encountered among the isolates from lily or tulip. These findings identify F. oxysporum f.sp. lilii as a single clonal lineage, distinct from F. oxysporum f.sp. gladioli and f.sp. tulipae. 相似文献
995.
新松叶蜂在蓝田林区一年发生一代,以卵在油松针叶内越冬。采用烟剂、喷粉和喷油烟防治,使有虫株率由95%下降到14%以下,单株虫口减退率达95% 相似文献
996.
以甜瓜枯萎病菌为试材,采用菌丝生长速率法和孢子萌发法从8种待选药剂中选出4种较优试剂进行复配试验,采用Wadley方法分别计算菌丝生长和孢子萌发的增效系数,确定最优配比并进行盆栽试验。结果表明:8种待选药剂中,25%腈菌唑乳油和45%咪鲜胺微乳剂对菌丝生长抑制效果较好,EC50值分别为0.001 2、0.004 6 mg·L^-1;250 g·L^-1嘧菌酯悬浮剂和25%啶菌恶唑乳油对孢子萌发抑制效果较好,EC50分别为0.092 2、3.263 2 mg·L^-1。上述4种药剂按比例法两两混配,30种组合中有2种配比对病菌菌丝生长及孢子萌发均为增效和加和作用,即咪鲜胺∶嘧菌酯=4∶1,嘧菌酯∶啶菌恶唑=2∶3。盆栽接种防效测定结果表明,上述2个组合每株浇灌10 mL浓度为1.0 g·L^-1药液对甜瓜枯萎病防治效果分别为80.42%和76.57%,均显著高于单剂防效。为甜瓜枯萎病的防治药剂使用提供参考依据。 相似文献
997.
毛蠼螋对蔗扁蛾幼虫的捕食作用 总被引:3,自引:0,他引:3
观察了捕食性天敌毛蠼螋对蔗扁蛾幼虫的捕食行为及捕食功能反应。结果表明,毛蠼螋对蔗扁蛾幼虫的捕食功能反应符合Holling模型,对1~3龄、4~5龄、6~7龄幼虫的捕食功能反应模拟模型分别是:Nα1~3=1.0849N0/(1 0.0220N0)、Nα4~5=1.1052N0/(1 0.0328N0)、Nα6~7=1.0291N0/(1 0.0384N0)。毛蠼螋在1d内最大的捕食量理论值。Nα(max)分别是49.26头、33.67头和26.81头。 相似文献
998.
The use of synthetic octoploids in strawberry breeding 总被引:1,自引:0,他引:1
W. D. Evans 《Euphytica》1977,26(2):497-503
Summary A number of methods of producing synthetic octoploids from Fragaria species of lower levels of ploidy are described. Six synthetic octoploids were produced from various combinations involving one hexaploid species, two tetraploid species and four diploid species. Three of the synthetic octoploids are male fertile and were used successfully as male parents in crosses with octoploid strawberry cultivars. 相似文献
999.
1000.
Water Use Efficiency, Carbon Isotope Discrimination and Biomass Production of Two Sugar Beet Varieties Under Well-Watered and Dry Conditions 总被引:3,自引:0,他引:3
R.-M. Rytter 《Journal of Agronomy and Crop Science》2005,191(6):426-438
Two sugar beet (Beta vulgaris sp.) varieties, which were supposed to differ in drought tolerance, were exposed to drought stress in a growth chamber and a container experiment in field. The aim was to test for (i) differences between the varieties in water use efficiency (WUE), biomass production and distribution and (ii) the relationship between WUE and carbon isotope discrimination (Δ), and between biomass production and Δ. Significant differences in WUE were detected between plants of well‐watered and drought treatments in both experiments, but not between the varieties. Production losses due to drought were large for both varieties in both experiments. Losses in the growth chamber were up to 50 % of plant dry weight and the corresponding value in the field was 24 %, when plants were given 60 and 30 %, respectively, of the full‐watered treatments. Significant negative correlations between WUE and Δ were found, but not between biomass production and Δ, when both varieties were included. Negative correlations between WUE and Δ were also found for each variety separately. The results suggest that Δ estimates from leaf tissue of sugar beet may provide a useful tool for genetic selection of drought‐tolerant sugar beet varieties. 相似文献