caa a22 4500 397570872 CHVBK 20180308164841.0 cr unu---uuuuu 161202e19960401xx s 000 0 eng 10.1093/ee/25.2.370 doi (NATIONALLICENCE)oxford-10.1093/ee/25.2.370 Spatial and Temporal Dynamics of Spider Mites (Acari: Tetranychidae) in ‘Thompson Seedless' Vineyards [Elektronische Daten] [Rachid Hanna, Lloyd T. Wilson, Frank G. Zalom, Donald L. Flaherty, George M. Leaviti] Quantitative knowledge of beneficial and pest arthropod distribution patterns in relation to plant vigor and habitat structure is essential for the development of reliable and cost-effective methods for the assessment and management of arthropod populations in agroecosystems. The spatial and temporal distributions of the spider mites, Tetranychus pacificus McGregor, Pacific spider mite, and Eotetranychus willamettei (McGregor) were determined in 3 ‘Thompson Seedless' grape, Vitis vinifera L., vineyards located in the central San Joaquin Valley of California. T pacificus was the dominant species in 2 of the vineyards, whereas E. willamettei was dominant in the 3rd vineyard. T. pacificus infestations were most severe in vineyard areas with low vine vigor compared with areas with high vigor. In contrast, E. willamettei appeared to be less sensitive to differences in vine vigor in the vineyards where the effect of vine vigor could be tested. Spatial variations in between- and within-vine distributions of spider mites were significant during most of the growing season in all vineyards. T. pacificus and E. willamettei distributions overlapped considerably on the south and north zones of vine canopy but differed between top and interior zones. The majority of T. pacificus and E. willamettei were found on leaves near the base of shoots during spring, and on midshoot leaves during summer. Aggregation indices indicated that both spider mite species were aggregated during most of the season, with T. pacificus being more aggregated between vines and within vines. The biological significance of T. pacificus and E. willamettei spatial dynamics are discussed along with implications for population assessment. © 1996 Entomological Society of America Population Ecology nationallicence Tetranychus pacificus nationallicence Eotetranychus willamettei nationallicence Vitis vinifera nationallicence plant vigor nationallicence spatial distribution nationallicence aggregation nationallicence Hanna Rachid Department of Entomology, University of California, Davis, CA 95616 aut Wilson Lloyd T. Department of Entomology, University of California, Davis, CA 95616 aut Zalom Frank G. Department of Entomology, University of California, Davis, CA 95616 aut Flaherty Donald L. Department of Entomology, University of California, Davis, CA 95616 aut Leaviti George M. Department of Entomology, University of California, Davis, CA 95616 aut Environmental Entomology Oxford University Press 25/2(1996-04-01), 370-382 0046-225X 25:2<370 1996 25 ee https://doi.org/10.1093/ee/25.2.370 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/ee/25.2.370 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hanna Rachid Department of Entomology, University of California, Davis, CA 95616 aut NATIONALLICENCE 700 1- Wilson Lloyd T. Department of Entomology, University of California, Davis, CA 95616 aut NATIONALLICENCE 700 1- Zalom Frank G. Department of Entomology, University of California, Davis, CA 95616 aut NATIONALLICENCE 700 1- Flaherty Donald L. Department of Entomology, University of California, Davis, CA 95616 aut NATIONALLICENCE 700 1- Leaviti George M. Department of Entomology, University of California, Davis, CA 95616 aut NATIONALLICENCE 773 0- Environmental Entomology Oxford University Press 25/2(1996-04-01), 370-382 0046-225X 25:2<370 1996 25 ee Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford