University of Nebraska
Viticulture Program
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CONCERNED ABOUT FOLIAR PHYLLOXERA? Although the root gall form of phylloxera is only a problem on classic winegrapes such as Chardonnay, Riesling, Merlot, Lemberger and other Vitis vinifera, some concern has been expressed about damage caused by the foliar form. (Note that all V. vinifera should be grafted onto phylloxera-resistant rootstocks.) The Midwest Commercial Small Fruit and Grape Spray Guide provides advice on treating the foliar form of phylloxera (once named Phylloxera vastatrix, now re-named Dactylasphaera vitifoliae). Chemicals recommended include (use only one) Endosulfan 50WP at 2 lb/acre or Endosulfan 3EC at 1.33 qt/ or, Danitol 2.4EC at 10.7 fl oz/A or Assail 30SG at 2.5 oz/A or Admire Pro at 7-14 fl oz/A. Timing is important! Application of insecticide should take place at bloom and again 10 to 14 days after bloom. Note that Endosulfan can cause severe phytotoxicity to cultivars such as Chambourcin, Concord, Baco Noir, Cynthiana/Norton, Chancellor and other cultivars (refer to product label for further notations of potential problem cultivars, also note that EC formulations are more likely to cause damage than WP formulations). Depending upon the severity of the previous year's infestations, one should carefully evaluate the economics of treatment, i.e., will the benefit of control justify the cost of the spray? Aesthetic considerations may warrant treatment even when there may not be a direct economic benefit. Moderate infestation of especially susceptible cultivars such as Frontenac may not warrant spraying, since Frontenac may be extremely vigorous on more fertile soils and a mild infestation of phylloxera may tend to reduce rampant vegetative growth. Some Nebraska and Midwest grape growers have reported that Danitol has provided desirable control of foliar phylloxeraa. As with all pesticides, always carefully read the label and follow all label restrictions and cautions. Remember, the label is a legal document and should be adhered to exactly. For further assistance with concerns about phylloxera, contact your Extension Educator or the University of Nebraska Viticulture Program staff (pread@unl.edu, 402-472-5136 or sgamet@unl.edu).
Spring VineLines - April/May 2008
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The InThe Institute of Agriculture and Natural Resources, University of Nebraska-Lincoln. It is the policy of the University of Nebraska-Lincoln not to discriminate on the basis of gender, age, disability, race, color, religion and marital status, veterans status, national or ethnic origin or sexual orientation.l Resources, University of Nebraska-Lincoln. It is the policy of the University of Nebraska-Lincoln not to discriminate on the basis of gender, age, disability, race, color, religion and marital status, veterans status, national or ethnic origin or sexual orientation.
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