Hann Patrick, Trska Claus, Wechselberger Katharina F, Eitzinger Josef, Kromp Bernhard
Bio Forschung Austria, Esslinger Hauptstrasse 132-134, Vienna, 1220 Austria ; MELES GmbH, Mörikestraße 20, St. Pölten, 3100 Austria.
Bio Forschung Austria, Esslinger Hauptstrasse 132-134, Vienna, 1220 Austria.
Springerplus. 2015 Mar 24;4:139. doi: 10.1186/s40064-015-0918-6. eCollection 2015.
The soil-dwelling larvae of several Scarabaeidae species (white grubs), like the cockchafer (Melolontha melolontha) and the garden chafer (Phyllopertha horticola), are serious pests in European cultivated grassland, reducing grass yield and destroying the turf by root-feeding. Nevertheless, the factors responsible for the development of large grub populations and the associated damage risk are poorly understood. The objectives of the study were to survey grub densities in grassland sites with different damage histories and find correlations with environmental and management variables. Data on grub densities were collected at 10 farms in the eastern Austrian Alps in September and October 2011. At each farm, one recently damaged site (high risk) and one site at which grub damage had never been observed by the farmers (undamaged site = low risk; each site: 500 m(2)) were sampled. All sites were dominated by P. horticola (99% of 1,422 collected individuals; maximum density 303 grubs/m(2)), which indicates that grub damage there is mainly caused by that species. Recently damaged sites tended to higher grub densities than undamaged sites. However, 3 out of 10 undamaged sites harbored high grub populations as well. Humus content together with the depth of the A-horizon significantly explained 38% of P. horticola grub density variance, with highest densities in deeper humus-rich soils. The risk of grub damage was positively connected to the humus content and negatively related to the cutting frequency. For the investigated mountainous grassland sites, these results suggest an important role of humus for the development of high grub densities and an effect of management intensity on grub damage.
几种金龟子科物种（蛴螬）生活在土壤中的幼虫，如五月鳃角金龟（Melolontha melolontha）和黄褐丽金龟（Phyllopertha horticola），是欧洲人工草地中的严重害虫，它们通过啃食根部降低草产量并破坏草皮。然而，导致蛴螬大量繁殖以及相关损害风险的因素却鲜为人知。本研究的目的是调查不同损害历史的草地中蛴螬的密度，并找出与环境和管理变量之间的相关性。2011年9月和10月，在奥地利东部阿尔卑斯山的10个农场收集了蛴螬密度数据。在每个农场，对一个近期受损的地块（高风险）和一个农民从未观察到蛴螬损害的地块（未受损地块=低风险；每个地块：500平方米）进行了采样。所有地块中黄褐丽金龟占主导（1422只采集个体中的99%；最大密度为303只蛴螬/平方米），这表明那里的蛴螬损害主要由该物种造成。近期受损的地块蛴螬密度往往高于未受损地块。然而，10个未受损地块中有3个也有大量蛴螬。腐殖质含量与A层土壤深度共同显著解释了黄褐丽金龟蛴螬密度变异的38%，在腐殖质丰富的深层土壤中密度最高。蛴螬损害风险与腐殖质含量呈正相关，与刈割频率呈负相关。对于所研究的山区草地地块，这些结果表明腐殖质对高密度蛴螬的发育具有重要作用，且管理强度对蛴螬损害有影响。
