《环境昆虫学报》

苦豆子Sophora alopecuroides L.是我国西北荒漠半荒漠地区防风固沙的主要物种之一，豆荚螟Etiella zinckenella是危害苦豆子种子的主要害虫，研究种子害虫豆荚螟及其寄生性天敌的空间分布格局，有利于预测害虫的发生，有效地设计生物防治措施，提高天敌的利用效率，从而保护生态环境和提升生态系统的稳定性。本研究于2024年6-7月在宁夏灵武白芨滩国家级自然保护区的刘家寨苦豆子自然生长区，采用地统计学方法对苦豆子种子害虫豆荚螟及其寄生性天敌的空间分布特征进行了研究。结果显示，苦豆子豆荚数平均为24.28荚/株，豆荚螟对豆荚的为害率为44.59%，豆粒的为害率为22.89%，豆荚螟的种群密度为13.18 ± 5.30头/株，有虫株率达100%。获得苦豆子豆荚螟的寄生性天敌共9种，隶属于茧蜂科、金小蜂科及扁股小蜂科，其中扁股小蜂Elasmus sp.1和金小蜂Pteromalus sp.2为优势种群。地统计学半变异函数最佳拟合模型显示苦豆子豆荚螟的为高斯模型，其寄生性天敌的为指数模型，空间分布格局均为聚集分布；苦豆子豆荚螟及其寄生性天敌存在一定空间相关性，空间依赖范围分别为25.00 m和46.25 m，其空间连续性强度分别是0.477和0.355。基于Kriging插值法的空间分布图显示苦豆子种子害虫及其寄生性天敌种群数量变化趋势相似，在空间上具有一定的关联，使得天敌能够有效地追随寄主而实现对寄主的控制。

英文摘要:

Sophora alopecuroides L. is a key species for windbreak and sand fixation in the desert and semi-desert regions of northwest China. Etiella zinckenella is the primary seed pest of S. alopecuroides, causing significant damage. Studying the spatial distribution patterns of E. zinckenella and its parasitic natural enemies is essential for predicting pest outbreaks, optimizing biological control strategies, enhancing the efficiency of natural enemy utilization, and ultimately contributing to ecosystem stability and environmental protection. This study was conducted from June to July 2024 in the natural habitat of S. alopecuroides in Liujiazhai, Ningxia Lingwu Baijitan National Nature Reserve. Geostatistical methods were employed to analyze the spatial distribution characteristics of E. zinckenella and its parasitic natural enemies. The results indicated that the average number of S. alopecuroides pods per plant was 24.28. The pod damage rate due to E. zinckenella infestation was 44.59%, while the seed damage rate was 22.89%. The population density of E. zinckenella was 13.18 ± 5.30 individuals per plant, with a 100% infestation rate among sampled plants. A total of nine species of parasitic natural enemies of E. zinckenella were identified, belonging to the families Braconidae, Pteromalidae, and Elasmidae. Among them, Elasmus sp.1 and Pteromalus sp.2 were the dominant species. Geostatistical semivariogram analysis revealed that the best-fitting model for E. zinckenella was the Gaussian model, whereas the exponential model best described the spatial distribution of its parasitic natural enemies, with both exhibiting aggregated spatial distribution pattern. A certain spatial correlation was observed between E. zinckenella and its parasitic natural enemies. The range of spatial dependence was 25.00 m for E. zinckenella and 46.25 m for its natural enemies, with spatial continuity intensities of 0.477 and 0.355, respectively. Spatial distribution maps generated via Kriging interpolation demonstrated similar population distribution trends between E. zinckenella and its natural enemies, indicating a spatial correlation. This suggests that natural enemies effectively track their host populations, facilitating host regulation and potential biological control.

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