Author
CHENG, XIAOMEI - UC-SAREP | |
Baumgartner, Kendra |
Submitted to: Proceedings of the Soil Environment and Vine Mineral Nutrition Symposium
Publication Type: Proceedings Publication Acceptance Date: 6/22/2004 Publication Date: 1/1/2005 Citation: Cheng, X., Baumgartner, K. 2005. Overlap of grapevine & cover crop roots enhances interactions among grapevines, cover crops, and arbuscular mycorrhizal fungi. Abstract AMERICAN SOCIETY OF ENOLOGY AND VITICULTURE ANNUAL MEETING. San Diego, CA., June 29-July 2, 2004. Interpretive Summary: Cover crops are often planted in between vineyard rows to prevent soil erosion and to improve soil fertility. The roots of grapevines and most vineyard cover crops are colonized by beneficial root fungi known as arbuscular mycorrhizal (AM) fungi. Assuming grapevines and cover crops share AM fungal species in common, contact among grapevine and cover crop roots may lead to development of a common mycorrhizal network that, in turn, may facilitate nutrient transfer from cover crops to grapevines. We examined grapevine root distribution and mycorrhizal colonization, at different soil depths and distances between grapevines, in trenches (180 100 90 cm) dug perpendicular to vineyard rows. Grapevine fine roots (<2 mm) were found at each sampling depth and distance. Root biomass was lower in the center of the vineyard middles (approximately 90 cm from the base of the vine trunk) than in the area closest to the vine trunk, especially in the top soil depth (0 - 40 cm). Fine root biomass was significantly greater in the three lower soil depths (20-40 cm, 40-60 cm, 60-80 cm) than in the top soil depth (0 - 20 cm). Very fine roots (<1 mm) collected from each sampling point were found to be colonized by AM fungi. Mycorrhizal colonization was generally greater at soil depths from 0 to 40 cm than from 40 to 80 cm, but did not appear to differ with respect to distance from either vine trunk. Overlap of mycorrhizal grapevine and cover crop roots may enhance belowground interactions between grapevines and cover crops, such as nutrient transfer between the two crops. Future work is needed to study the effects of different cover crop management practices on these interactions. Technical Abstract: Cover crops are often planted in between vinerows to reduce soil erosion, and improve soil fertility and structure. The roots of grapevines and most vineyard cover crops are colonized by beneficial root fungi known as arbuscular mycorrhizal (AM) fungi. Assuming grapevines and cover crops share AM fungal species in common, contact among grapevine and cover crop roots may lead to development of a common mycorrhizal network that, in turn, may facilitate direct nutrient transfer from cover crops to grapevines. We quantified grapevine root biomass and mycorrhizal colonization, at different soil depths and distances between grapevines, in trenches (180 100 90 cm) excavated perpendicular to vinerows. Grapevine fine roots (<2 mm) were found at each sampling depth and distance. Root biomass was lower in the center of the vineyard middles (approximately 90 cm from the base of the vine trunk) than in the area closest to the vine trunk, especially in the top soil depth (0 - 40 cm). Fine root biomass was significantly greater in the three lower soil depths (20-40 cm, 40-60 cm, 60-80 cm) than in the top soil depth (0 - 20 cm). Very fine roots (<1 mm) collected from each sampling point were found to be colonized by AM fungi. Mycorrhizal colonization was generally greater at soil depths from 0 to 40 cm than from 40 to 80 cm, but did not appear to differ with respect to distance from either vine trunk. Overlap of mycorrhizal grapevine and cover crop roots may enhance belowground interactions between grapevines and cover crops, such as nutrient transfer between the two crops. Future work is needed to study the effects of different cover crop management practices on these interactions. |