Grapevine Injury and Fruit Yield Response to Simulated Auxin Herbicide Drift

Abstract

Grape growers are concerned about the potential impact of drift from commonly used auxinic herbicides. In California, this is frequently related to herbicides used in cereals and noncrop areas, whereas in other parts of the United States concerns are often related to dicamba- and 2,4-D-resistant cropping systems. Our objective was to compare the relative sensitivity of winegrapes to simulated auxinic herbicide drift, including grapevine symptomology, grape yield, and grape quality. In a small-plot herbicide evaluation, we applied 1/900×, 1/300×, 1/100×, and 1/33× rates of 2,4-D, aminopyralid, dicamba, and triclopyr based on 1× field rates of 1454, 122.5, 280, and 2240 g⋅ha–1 ae, respectively. Aminopyralid resulted in similar symptomology to 2,4-D and dicamba—namely, leaf cupping, leaf crinkling, excessive tendril twisting, and tendril death, although these symptoms were generally subtle. Triclopyr resulted in much greater levels of necrosis compared with the other herbicides. In our study, triclopyr was the only herbicide associated with grape yield loss, and greater triclopyr rates were also associated with increased grape sugar levels. This study demonstrates that grapes are sensitive to low rates of simulated herbicide drift, but symptoms do not necessarily indicate yield loss or quality effects. This study indicates that auxin-type herbicide simulated drift symptoms are not reliable markers for winegrape yield or quality reduction.

Organic Mulches as an Alternative to Conventional Under-Vine Weed Management in Mediterranean Irrigated Vineyards

“…The use of herbicides has been proven more effective than tillage in controlling vineyard weeds, being more cost-effective and easier to use, which has justified their use in weed management [ 6 ]. However, herbicides may cause many problems linked to environmental contamination and human health [ 7 ], a high risk of toxicity to both humans and vines [ 8 ], the potential impact of drift from commonly used auxin herbicides to leaves and grapes [ 9 ] and a reduction in root mycorrhization, which alters the nutrient composition in grapevine roots, leaves or grape juice [ 10 ]. Moreover, herbicides’ success is limited, depending on the characteristics of the weed species, the timing of the application and the weather conditions.…”

Hazelnut abscission is delayed by simulated drift of 2,4-D

“…), foliar treatment with 2,4-D at 18 ppm 6 wk before harvest suppressed fruit abscission, delaying harvest by a month (Zur and Goren 1977). A simulated 2,4-D drift arrested pecan fruit development (Wells et al 2019), and uneven ripening was reported after 2,4-D drift in grape (Haring et al 2022; Ogg et al 1991; Weigle et al 1970).…”

Chemical Weed Control and Crop Injuries Due to Spray Drift: The Case of Dicamba

“…[7,17,18] Rice (Oryza sativa L.) [19] Cotton (Gossypium hirsutum L.) [20] Peanut (Arachis hypogaea L.) [21] Tomato (Solanum lycopersicum L.) [18,22,23] Lettuce (Lactuca sativa L.) [18] Pumpkin (Cucurbita maxima Duch) [18] Oilseed rape (Brassica napus L.) [18] Pepper (Capsicum annuum L.) [18] Sunflower (Helianthus annuus L.) [18] Cucumber (Cucumis sativus L.) [7] Eggplant (Solanum melongena L.) [7] Snap bean (Phaseolus vulgaris L.) [7] Potato (Solanum tuberosum L.) [24] Sweetpotato (Ipomoea batatas (L.) Lam.) [25] Mandarin (Citrus reticulata) [26] Grapevine (Vitis vinifera L.) [27] Brazilian peppertree (Schimus terebinthifolius Raddi.) [28] Consequently, it is noted that the problem is obvious and ongoing not only in arable but also in horticultural and perennial crops.…”