Wine Quality
Answers to Questions on
The Effect of M-Pede on Wine Quality
M-Pede Insecticide/Fungicide effectively controls powdery mildew disease as well as a wide range of soft bodied insects and mites on grapes and other food and ornamental crops. M-Pede is a curative fungicide which kills powdery mildew colonies and spores on contact. It is composed of fatty acid salts which are derived from natural sources. M-Pede is a unique insecticide and fungicide tool for grape producers. The following are answers to commonly asked questions concerning the effect of M-Pede on wine grapes.
I. Does the application of M-Pede to wine grapes affect fermentation?
No. Research to date indicates that the use of M-Pede does not cause "sticking" or inhibit normal fermentation.
Mycogen laboratory trials in 1992 and 1993 using Chardonnay grapes treated with
M-Pede resulted in normal fermentation. University trials (Catholic University, Chile, 1993) using M-Pede treated Chardonnay grapes also indicated no fermentation problems.
Cabernet Sauvignon, Pinot Noir, and Chardonnay grapes picked from 14 vineyards in Monterey, Napa and Sonoma Counties which received multiple applications of M-Pede, were fermented in 1993. No fermentation problems were encountered.
Wine was produced commercially from Chardonnay grapes which received six M-Pede applications in Riverside County. The wine met all winery quality standards and has been bottled and sold.
II. Is the appearance of grapes treated with M-Pede a problem for wine makers?
No. The application of M-Pede to berries may effect their appearance by modifying their waxy bloom. Application to table grapes over 6-7 mm in diameter is discouraged; however, the modification of waxy bloom should not be a problem for wine grape producers.
III. Does M-Pede impart any off-tastes, flavors or odors to wine produced from treated grapes? No. Research experience indicates that this does not occur. Wine has been produced from grapes which have been treated with M-Pede for insect control for a number of years. No wine quality problems have been reported.
Mycogen laboratory trials in 1993 in which Chardonnay must was spiked with M-Pede resulted in normal fermentation with no off-tastes, flavors or odors. University enology trials (Catholic University, Chile, 1993) which fermented Chardonnay must spiked with
M-Pede resulted in normal fermentation with no wine quality problems.
Cabernet Sauvignon grapes from an 11 acre block in Napa which received two applications of M-Pede were fermented separately. The fermentation proceeded normally and the wine quality was reported to be excellent.
IV. Does the application of M-Pede to wine grapes affect their sugar and acid content at maturity? No. The use of M-Pede to control powdery mildew or insect pests results in economic control and plant health leading to normal grape size and composition. Research indicates that the use of M-Pede has no negative effect on the quality of grapes treated.
Chardonnay grapes harvested from a trial in which powdery mildew was controlled by either four applications of a standard sterol inhibitor fungicide, sulfur or M-Pede were evaluated for sugar content and acidity. No statistical difference in quality was detectable from grapes harvested from M-Pede plots versus the standard commercial programs (Refer to graph).
V. Does the application of M-Pede to grapes increase their susceptibility to botrytis? No. Careful inspection of grapes treated with M-Pede in university trials and large commercial plots in 1992 and 1993 did not demonstrate any difference in susceptibility to botrytis disease from grapes in other treatments or untreated control plots. Research has suggested that certain synthetic wetting agents and spray adjuvants can increase the susceptibility of grapes to botrytis infection. However, Mycogen research has not observed this to be true for grapes treated with
M-Pede.
Always read and follow all label instructions.
M-Pede is a registered trademark of Mycogen Corporation.
M-Pede EPA Registration No. 53219-6 MYC JJ# 2177, 3/94