ABSTRACT The Christmas tree industry is mainly supplied with seeds from natural stands and genetically improved germplasm from clonal seed orchards (CSOs). Chalcid wasps (Megastigmus spp.) have a negative effect on the value of seedlots by reducing the quantity of viable seeds and represent a risk for national and international seed trade. Seed radiographies, field observations and seed-dissections from 25 Fraser fir (Abies fraseri (Pursh) Poir.) clones were used to determine chalcid infestation in a CSO of the southern Appalachians. We provided direct evidence that Mesopolobus cf. pinus is an ectoparasitoid of M. specularis, proposed a model that linked different aspects of the biology of these species and discussed host–insect phenological relationships. Infestation of seeds in some clones across surveys, suggested a potential genetic component to chalcid wasp's prevalence. Cold and dark rearing regimens were used to identify changes in adult insect emergence after variation of overwinter conditions. Both the frequency and the time of emerging M. specularis adults from seeds were affected by the duration of the treatments but not statistical differences were found for Mesopolobus cf. pinus. We present evidence for the efficiency of a gravity-seed cleaning method eliminating upwards of 95% of chalcid-infested seeds.

中文翻译：

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在南阿巴拉契亚山脉的弗雷泽冷杉（Abies fraseri (Pursh) Poir.）克隆种子园中评估 Megastigmus specularis（膜翅目：Megastigmidae）的侵染

摘要 圣诞树产业主要供应来自天然林分的种子和来自克隆种子园 (CSO) 的遗传改良种质。Chalcid wasps (Megastigmus spp.) 通过减少可存活种子的数量对苗圃的价值产生负面影响，并对国家和国际种子贸易构成风险。使用来自 25 个弗雷泽冷杉（Abies fraseri (Pursh) Poir.）克隆的种子射线照相、实地观察和种子解剖来确定阿巴拉契亚南部 CSO 中的 chalcid 感染。我们提供了直接证据表明 Mesopolobus 比照。pinus 是 M. specularis 的一种外寄生物，提出了一个模型，将这些物种的生物学的不同方面联系起来，并讨论了宿主 - 昆虫的物候关系。跨调查的一些克隆中种子的侵染，提出了 chalcid wasp 流行的潜在遗传成分。冷和暗饲养方案用于确定越冬条件变化后成虫出现的变化。从种子中出现的 M. specularis 成虫的频率和时间都受处理持续时间的影响，但没有发现 Mesopolobus cf 的统计差异。松。我们提供了证据证明重力种子清洁方法可以消除 95% 以上的受硫菌侵染的种子。来自种子的 specularis 成虫受到处理持续时间的影响，但没有发现 Mesopolobus cf 的统计差异。松。我们提供了证据证明重力种子清洁方法可以消除 95% 以上的受硫菌侵染的种子。来自种子的 specularis 成虫受到处理持续时间的影响，但没有发现 Mesopolobus cf 的统计差异。松。我们提供了证据证明重力种子清洁方法可以消除 95% 以上的受硫菌侵染的种子。