Visual and PCR assessment of light leaf spot (Pyrenopeziza brassicae) on winter oilseed rape (Brassica napus) cultivars
Visual and PCR assessment of light leaf spot (Pyrenopeziza brassicae) on winter oilseed rape (Brassica napus) cultivars
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DOI：
10.1111/j.1365-3059.2006.01383.x
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发表时间：
2006-06-01
期刊：
影响因子：
2.7
通讯作者：
Evans, N.
中科院分区：
文献类型：
--
作者：
Karolewski, Z.;Fitt, B. D. L.;Evans, N.
在实验室、受控环境和田间试验中比较了评估冬季油菜品种轻叶斑病（Pyrenopeziza bassicae）的方法。在 GS 1,4 接种幼苗叶片的受控环境实验中，在接种浓度为 4 x 10(3) 或 4 x 10(4) 孢子 mL(-1)，而不是 4 x 10(2) 或 4 x 10(5) 孢子 mL(-1) 时，观察到受甘蓝假单胞菌孢子形成影响的百分比面积的最大差异，但较老的叶子在评估前已开始衰老，特别是在哪里 他们受到芸苔假单胞菌的严重影响。在冬季油菜田间试验中，2002/03 年（接种后，9 月/10 月降雨量 127.2 毫米）发生了严重的轻微叶斑病流行，但 2003/04 年度则没有发生（未接种，9/10 月降雨量 40.7 毫米）。地块内评估在 2003 年 2 月/3 月和 2004 年 6 月对品种的区分效果最好，但有时无法检测到有许多受感染植物的地块（例如 2004 年 3 月/4 月）。在受控环境条件下进行的幼苗实验和田间实验之间的品种抗性排名有所不同。使用 PCR 引物对 PbITSF/PbITSR 检测从培养物中提取的甘蓝菜 DNA 的灵敏度高于使用引物 Pb1/Pb2 的灵敏度。在接种后立即和长达 14 天的受控环境实验的叶子中，以及在通过目视评估检测前 2 个月从田间实验中取样的叶子中，通过 PCR（PbITS 引物）检测到了芸苔假单胞菌。
Methods to assess light leaf spot (Pyrenopeziza brassicae) on winter oilseed rape cultivars were compared in laboratory, controlled-environment and field experiments. In controlled-environment experiments with seedling leaves inoculated at GS 1,4, the greatest differences in percentage area affected by P. brassicae sporulation were observed with inoculum concentrations of 4 x 10(3) or 4 x 10(4) spores mL(-1), rather than 4 x 10(2) or 4 x 10(5) spores mL(-1), but older leaves had begun to senesce before assessment, particularly where they were severely affected by P. brassicae. In winter oilseed rape field experiments, a severe light leaf spot epidemic developed in 2002/03 (inoculated, September/October rainfall 127.2 mm) but not in 2003/04 (uninoculated, September/October rainfall 40.7 mm). In-plot assessments discriminated between cultivars best in February/March in 2003 and June in 2004, but sometimes failed to detect plots with many infected plants (e.g. March/April 2004). Ranking of cultivar resistance differed between seedling experiments done under controlled-environment conditions and field experiments. The sensitivity of detection of P. brassicae DNA extracted from culture was greater using the PCR primer pair PbITSF/PbITSR than using primers Pb1/Pb2. P. brassicae was detected by PCR (PbITS primers) in leaves from controlled-environment experiments immediately and up to 14 days after inoculation, and in leaves sampled from field experiments 2 months before detection by visual assessment.