Evaluation of spatial and temporal patterns of insect damage and aflatoxin level in the pre-harvest corn fields to improve management tactics  

作　　者：Xinzhi Ni Jeffrey P. Wilson Michael D. Toews G. David Buntin R. Dewey Lee Xin Li Zhongren Lei Kanglai He Wenwei Xu Xianchun Li Alisa Huffaker Eric A. Schmelz 

机构地区：[1]USDA-ARS, Crop Genetics and Breeding Research Unit [2]Department of Entomology, University of Georgia, Tifton [3]Department of Entomology, University of Georgia, Griffin [4]Department of Crop and Soil Sciences, University of Georgia, Tifton, Georgia, USA [5]Collegeof Plant Protection, Northwest A&F University, Yangling, Shaanxi [6]State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China [7]Texas A&M University, Texas AgriLife, Lubbock,Texas [8]Department of Entomology, University of Arizona, Tucson, Arizona [9]USDA-ARS, Center for Medical, Agricultural, and Veterinary Entomology, Gainesviile, Florida, USA

出　　处：《Insect Science》2014年第5期572-583,共12页昆虫科学（英文版）

摘　　要：Spatial and temporal patterns of insect damage in relation to aflatoxin contamination in a corn field with plants of uniform genetic background are not well understood. After previous examination of spatial patterns of insect damage and aflatoxin in pre-harvest corn fields, we further examined both spatial and temporal patterns of cob- and kernel- feeding insect damage, and aflatoxin level with two samplings at pre-harvest in 2008 and 2009. The feeding damage by each of the ear/kernel-feeding insects （i.e., corn earworm/fall armyworm damage on the silk/cob, and discoloration of corn kernels by stink bugs） and maize weevil population were assessed at each grid point with five ears. Sampling data showed a field edge effect in both insect damage and aflatoxin contamination in both years. Maize weevils tended toward an aggregated distribution more frequently than either corn earworm or stink bug damage in both years. The frequency of detecting aggregated distribution for aflatoxin level was less than any of the insect damage assessments. Stink bug damage and maize weevil number were more closely associated with aflatoxin level than was corn earworm damage. In addition, the indices of spatial-temporal association （χ） demonstrated that the number of maize weevils was associated between the first （4 weeks pre-harvest） and second （1 week pre-harvest） samplings in both years on all fields. In contrast, corn earworm damage between the first and second samplings from the field on the Belflower Farm, and aflatoxin level and corn earworm damage from the field on the Lang Farm were dissociated in 2009.Spatial and temporal patterns of insect damage in relation to aflatoxin contamination in a corn field with plants of uniform genetic background are not well understood. After previous examination of spatial patterns of insect damage and aflatoxin in pre-harvest corn fields, we further examined both spatial and temporal patterns of cob- and kernel- feeding insect damage, and aflatoxin level with two samplings at pre-harvest in 2008 and 2009. The feeding damage by each of the ear/kernel-feeding insects （i.e., corn earworm/fall armyworm damage on the silk/cob, and discoloration of corn kernels by stink bugs） and maize weevil population were assessed at each grid point with five ears. Sampling data showed a field edge effect in both insect damage and aflatoxin contamination in both years. Maize weevils tended toward an aggregated distribution more frequently than either corn earworm or stink bug damage in both years. The frequency of detecting aggregated distribution for aflatoxin level was less than any of the insect damage assessments. Stink bug damage and maize weevil number were more closely associated with aflatoxin level than was corn earworm damage. In addition, the indices of spatial-temporal association （χ） demonstrated that the number of maize weevils was associated between the first （4 weeks pre-harvest） and second （1 week pre-harvest） samplings in both years on all fields. In contrast, corn earworm damage between the first and second samplings from the field on the Belflower Farm, and aflatoxin level and corn earworm damage from the field on the Lang Farm were dissociated in 2009.

关 键 词：aflatoxin level corn earworm damage maize weevil population SADIE analysis spatial pattern spatio-temporal association stink bug damage 

分 类 号：S451.222[农业科学—植物保护] TS207.4[轻工技术与工程—食品科学]