Author
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SWEET, REBECCA - Oregon State University |
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Schreiner, Roger - Paul |
Submitted to: American Journal of Enology and Viticulture
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/9/2009 Publication Date: 6/1/2010 Citation: Sweet, R., Schreiner, R.P. 2010. Alleyway cover crops have little influence on Pinot noir grapevines (Vitis vinifera L.) in two western Oregon Vineyards. American Journal of Enology and Viticulture. 61:240-252. Interpretive Summary: This study investigated whether of not various cover crops grown in vineyard alleys (but not under vines) and managed by mowing in spring and summer in western Oregon would compete with the grapevines for nutrients or water. While cover crop treatments had a minor effect on certain variables we measured, none of the cropped treatments was different from the clean cultivated control. Our results show that alleyway cover crops managed by spring and summer mowing do not compete significantly with grapevines in western Oregon vineyards. Technical Abstract: Seven cover crop treatments were compared in two north Willamette Valley ‘Pinot noir’ vineyards over two years to test if alleyway cover crops that are mowed in spring and summer compete with grapevines for water or nutrients. Five different cover crop mixtures (planted in the fall of 2003) were compared to a clean-cultivated control and resident vegetation treatments in 2004 and 2005. Treatments were evaluated for biomass production, quantity of nitrogen contributed to the vineyard floor, weed suppression, and effect on soil water content. Vine responses to the different floor management strategies included measures of shoot growth, water stress, nutrient status, yield, and juice quality. Three treatments were evaluated for their effect on fine root production and colonization by arbuscular mycorrhizal fungi (AMF). A wide range of biomass was produced in different cover crop treatments at each site, and a greater degree of vine water stress consistently occurred at the youngest vineyard. Cover crops had only minor impacts on grapevines; altering leaf N concentrations at véraison, and yeast available nitrogen (YAN) in juice. Even in these cases, however, no cover crop treatment was significantly different from the clean cultivated control. Cover crops altered leaf nutrient concentrations (P, K, S, B, Fe, and Zn), but effects were small and not consistent over time. Cover crops did not alter shoot growth, leaf N concentrations at bloom, leaf water potential, fine root density or colonization of roots by AMF; nor did cover crops affect yield, cluster weights, juice soluble solids, pH, or titratable acidity. Our data show that alleyway cover crops managed by spring and summer mowing do not compete significantly with grapevines in western Oregon vineyards. |