Gaylord I. Mink

Leaf photosynthesis, stomatal resistance, and growth of wine grapes (Vitis vinifera L.) after exposure to simulated chlorsulfuron drift

Abstract The lower Yakima Valley of Washington is a highly diversified irrigated agricultural region bordered by dryland wheat fields. Residues of herbicides sprayed in wheat can be atmospherically transported to susceptible nontarget crops in the valley. Nontarget crops may be exposed repeatedly to low levels of herbicide residues. The effects on grapes exposed to phenoxyacetate herbicide drift has been well documented, but the effects of comparatively newer wheat herbicides like sulfonylureas (SUs) are less known. Potential effects of repeated exposures of grapes to an SU herbicide were assessed in a simulated drift study. Grape vines of the cultivar “Lemberger”; were sprayed up to three times at a weekly interval with 1/100 (0.01X) of a field application rate of chlorsulfuron, which is a postemergence wheat herbicide. Thirty‐five days after the first application, photosynthesis and stomatal resistance of randomly tagged, fully expanded leaves were measured. Total leaf area and chlorotic leaf area were ...

The Economic Impact of Filamentous Plant Viruses

An attempt has here been made to picture the global effects of filamentous viruses by asking authorities in different world regions to assemble a hit parade of their 10 favorite viruses—favorite in the sense that a true pathologist always relishes a good, destructive disease.

Using sentinel plants as biomonitors of herbicide drift and deposition

Abstract Chemical analyses of air and precipitation have documented a widespread occurrence of pesticide residues over both intensively farmed regions and areas remote from agriculture. The health or ecological significance of the low levels detected is obscure, but drift of herbicide residues during spraying has sometimes damaged nearby nontarget crops. Monitoring of herbicide residue deposition, whether resulting from direct drift or following long‐range transport, is highly desirable to determine possible adverse effects on yield. Although chemical assays can confirm the identity of residues, their use in intensive regional sampling studies can be expensive. Certain herbicide groups are difficult to detect. Furthermore, the mere presence of a residue does not easily translate into an assessment of biological effect. Although not as specific as chemical analyses, biological assays with sentinel plants can be used to detect classes of herbicides with unique modes of action and characteristic injury patte...