Field surveys were conducted on golf courses reporting the inability of imidacloprid to control white grubs (Coleoptera: Scarabaeidae) when applied preventively. Surveys of five sites with significant past imidacloprid use (>10 years) revealed significantly greater white grub populations in rough-mown turf following imidacloprid treatment than that of adjacent short-mown fairways. Additionally, spatial analysis by distance indicEs (SADIE) analyses demonstrated a positive correlation between white grub and thatch spatial patterns. To investigate the impact of thatch on imidacloprid efficacy and translocation throughout the turfgrass plant, greenhouse experiments were conducted using turf with differing thatch levels. Imidacloprid concentrations in soil and plant tissues were measured with high-performance liquid chromatography (HPLC) and compared to values obtained through an enzyme-linked immunosorbent assay (ELISA) kit to determine if the latter could be a cost-effective alternative in future studies. ELISA provided reliable estimates of concentrations of imidacloprid compared to HPLC, with only minor discrepancies noted across different types of treatments and assessment timings. Despite finding higher imidacloprid levels in leaf tissues compared to roots and some differences in concentration across thatch treatments, there was no clear pattern showing that thatch thickness significantly affects imidacloprid penetration or accumulation in plant tissues or soil over time. These findings suggest that factors other than thatch thickness may contribute to the observed field failures of imidacloprid in controlling white grubs. Further research is necessary to identify these factors and optimize the use of imidacloprid in turfgrass pest management strategies.

中文翻译：

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研究吡虫啉处理的草坪草中茅草和白蛴螬种群之间的空间关联


对高尔夫球场进行了实地调查，报告称在预防性使用时，吡虫啉无法控制白色蛴螬（鞘翅目：Scarabaeidae）。对过去大量使用吡虫啉的五个地点（x3E10 年）的调查显示，在吡虫啉处理后，粗草坪上的白蛴螬数量明显多于相邻的短草球道。此外，通过距离指示进行空间分析 （SADIE） 分析表明，白蛴螬和茅草空间模式之间存在正相关关系。为了研究茅草对吡虫啉功效和整个草坪草植物易位的影响，使用不同茅草含量的草坪进行了温室实验。用高效液相色谱法 （HPLC） 测量土壤和植物组织中的吡虫啉浓度，并与通过酶联免疫吸附测定 （ELISA） 试剂盒获得的值进行比较，以确定后者在未来研究中是否是一种具有成本效益的替代方案。与 HPLC 相比，ELISA 提供了可靠的吡虫啉浓度估计值，在不同类型的治疗和评估时间中仅观察到微小的差异。尽管发现与根相比，叶组织中的吡虫啉水平更高，并且茅草处理之间的浓度存在一些差异，但没有明确的模式表明茅草厚度会随着时间的推移显着影响吡虫啉在植物组织或土壤中的渗透或积累。这些发现表明，茅草厚度以外的因素可能导致观察到的吡虫啉在控制白蛴螬方面的田间失败。需要进一步的研究来确定这些因素并优化吡虫啉在草坪草害虫管理策略中的使用。