7 pp.

Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. / Includes bibliographical references (leaves 68-72) / Microfiche. / ix, 73 leaves, bound col. ill. 29 cm

Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Heading on microfiche: Peabody, Nathan Clement. Includes bibliographical references (leaves 106-119). Also available on microfiche.

Thèse--Toulouse. / Reprint of the edition published in Toulouse, 1906. Bibliography: p. [3]-7.

4 pp.

Early season infestations of sweet potato whiteflies, Bemisia tabaci ( Gennadius) were monitored in fields of cantaloupe, Cucumis melo L., near Yuma, Arizona. We used these data to describe the relationship between the proportion of infested leaves and mean adult population density for the entire field. This model was used to develop a binomial sampling plan based on a presence- absence approach. We evaluated the model with three independent data sets, and the level of agreement between the model and data was reasonable for pest management purposes. A minimum sample size of 200 leaves is suggested for maximum accuracy. By turning over 50 leaves in the four quadrants of a field and determining what proportion have whiteflies (i.e., are there whitefly adults on the leaf or not), growers can estimate field populations. We recommend that if 60% of the sampled leaves have whiteflies then it is time to make a pesticide application because that tells you that population levels are approaching 3 adults per leaf.

A study was conducted in 1995 to evaluate five application technologies in the field in terms of deposition efficiency, as well as to assess their abilities to control the sweet potato whitefly and thereby influence crop yield. The FMC and ESS-on treatments provided the greatest deposition on the ventral side of the leaves. The FMC system tended to maintain high ventral deposition efficiencies as the plants grew and the canopy closed, whereas the efficiency of the ESS declined. Differences in ventral deposition efficiency among treatments were not closely associated with differences in whitefly control, although the declining rate of ventral deposition for the ESS-on is also reflected in its declining superiority in adult insect control relative to the CDA and conventional systems. The ESS sprayer provided somewhat better whitefly control than the conventional treatment, and was also associated with a higher yield of #12 melons than the control and Admire treatments, but not better than the conventional treatment. Early control of adults was associated with reduced egg counts later in the season, suggesting that there may be long term control advantages with the ESS system. New application technologies need to be developed to obtain higher ventral deposition and maximum whitefly control, with minimum use of insecticides.

No description available.

The efficacy and field performance of new insecticides for control of insects on vegetables and melons under desert growing conditions has been investigated in small plot trials for the past several years at the Yuma Agricultural Center. Our objective has been to determine how new chemistries will fit into the growers management programs in Arizona. Thus, our research programs have been focused on studies to determine how to integrate these new chemicals into our local management programs in the most cost/effective way possible. This document was created to provide you with an overview of new insecticide chemistries being developed by the Agrichemical Industry for use in vegetables. The first part of this report concisely describes the new types of chemistries being developed The tabular information presented is a summary of the efficacy and activity of the new compounds based on research we have conducted at the Yuma Agricultural Center.

For the past 5 years, Arizona growers have been faced with the challenge of managing whiteflies populations to prevent yield reduction and loss of quality of their vegetable and melon crops. A large cooperative research effort was directed statewide to better understand how whiteflies develop on the numerous host -crops available and the environmental factors that influence their survival throughout the year. This information was used to develop short and long term management approaches for controlling whitefly populations. We quickly discovered that preventing whiteflies from colonizing plants was the key to successful management of whitefly populations in vegetable and melon crops. This report attempts to summarize what we presently understand about factors that influence the seasonal abundance of whiteflies in southern Arizona cropping systems. Non-chemical and chemical management approaches that have been developed by researchers and implemented by the agricultural communities are discussed