Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: A General Method for Estimating Cereal Aphid Populations in Small Grain Fields Based on Frequency of Occurrence (Correcting Title and Adding Acceptance Date)

Authors
item Hein, Gary - UNIV OF NEBRASKA
item Elliott, Norman
item Michels, Jr, G - TEXAS A&M UNIV
item Kieckhefer, Robert

Submitted to: The Canadian Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 6, 1994
Publication Date: N/A

Interpretive Summary: A major impediment to the acceptance of insect sampling methods in relatively low-value small grain crops is that they are too complex to be carried out with reasonable time and effort. One way that sampling might be made more effective is to develop sampling plans for pest complexes rather than individual species. A step toward this approach is to develop sampling gplans for complexes of closely related species, such as cereal aphids. Utilizing information obtained from published reports we developed a general model for predicting cereal aphid population intensity on wheat tillers. Statistical analysis of the predicted values compared with observed values showed that our general model provides accurate and relatively precise prediction of population intensity for each species and therefore provides a basis for developing a single plan that can be used for sampling mixed species cereal aphid infestations.

Technical Abstract: A major impediment to the acceptance of sampling methods in relatively low- value small grain crops is that they are too complex to be carried out with reasonable time and effort. One way that sampling might be made more effective is to develop sampling plans for pest complexes rather than individual species. A step toward this approach is to develop sampling plans for complexes of closely related species. A total of 15 sets of estimates of parameters were obtained from published reports of a model relating the proportion of wheat tillers infested with a particular species of cereal aphid to the mean number of each species per tiller. The parameters were used to develop a general model for predicting cereal aphid population intensity. Coefficients of determination of linear regressions of predicted (from the general model) versus the observed mean number of aphids per tiller (transformed to logarithms) for each of four aphid species ranged from 0.74 for Diuraphis noxia to 0.96 for Sitobion avenae. Neither the slopes nor intercepts of any of the four regressions differed significantly from one or zero, respectively. The regression analyses indicate that the general model provides accurate and relatively precise prediction of population intensity for each species and therefore provides a basis for developing a single plan that can be used for sampling mixed species cereal aphid infestations.

Last Modified: 11/26/2014
Footer Content Back to Top of Page