Skip to main content
ARS Home » Pacific West Area » Davis, California » Crops Pathology and Genetics Research » Research » Publications at this Location » Publication #265686
Title: The relationship between root hydraulics and scion vigour accross Vitis rootstocks: what role do root aquaporins play?

Author
item GAMBETTA, GREG - University Of California
item MANUCK, CHRISTINE - US Department Of Agriculture (USDA)
item DRUCKER, SOPHIE - University Of California
item SHAGHASI, TARANA - University Of California
item FORT, KEVIN - University Of California
item MATTHEWS, MARK - University Of California
item WALKER, ANDREW - University Of California
item McElrone, Andrew

Submitted to: Journal of Experimental Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/3/2012
Publication Date: 11/7/2012
Citation: Gambetta, G.A., Manuck, C.M., Drucker, S.T., Shaghasi, T., Fort, K., Matthews, M.A., Walker, A.M., Mcelrone, A.J. 2012. The relationship between root hydraulics and scion vigour accross Vitis rootstocks: what role do root aquaporins play?. Journal of Experimental Botany. 63(18):6445-6455.

Interpretive Summary: Vitis vinifera scions are grafted onto rootstocks of other grapevine species to provide resistance to soil-borne pests, confer abiotic stress resistance, and influence scion vigor. Despite their common usage, the mechanisms by which rootstocks affect scion vigor and stress resistance are unknown for grapevines and ambiguous across other perennial fruit crops. In this study, we characterized the hydraulic physiology of Vitis rootstocks known to vary in vigor and stress resistance by investigating aquaporin (VvPIP) gene expression, aquaporin protein activity, fine root hydraulic conductivity (Kh), and scion transpiration. Growth in greenhouse experiments was consistent with previous vigor ratings and findings from recent mutlti-year, multi-site field trials accross California; leaf area and/or root biomass were significantly greater for rootstocks 110R and 1103P compared to 101-14Mgt and 420A. Expression of genes from VvPIP1 and VvPIP2 families was significantly greater in the high-vigor rootstocks in both soil and hydroponics. However, significantly higher VvPIP expression in non-lignified root tips compared to lignified fine roots suggest that high aquaporin activity may not be conferred evenly to an entire root system. Leaf area specific transpiration rates were greater for vines with 110R rootstock compared to 420A, and root weight normalized Kh was tightly correlated with transpiration and greatest for high vigor rootstocks. Despite the positive correlation between VvPIP expression and vigor, varied rootstock Kh in this study appears to result primarily from differences in root system biomass and to a lesser or negligible extent by differences in fine root Kh associated with aquaporin activity.

Technical Abstract: Vitis vinifera scions are grafted onto rootstocks of other grapevine species to provide resistance to soil-borne pests, confer abiotic stress resistance, and influence scion vigor. Despite their common usage, the mechanisms by which rootstocks affect scion vigor and stress resistance are unknown for grapevines and ambiguous across other perennial fruit crops. In this study, we characterized the hydraulic physiology of Vitis rootstocks known to vary in vigor and stress resistance by investigating aquaporin (VvPIP) gene expression, aquaporin protein activity, fine root hydraulic conductivity (Kh), and scion transpiration. Growth in greenhouse experiments was consistent with previous vigor ratings and findings from recent mutlti-year, multi-site field trials accross California; leaf area and/or root biomass were significantly greater for rootstocks 110R and 1103P compared to 101-14Mgt and 420A. Expression of genes from VvPIP1 and VvPIP2 families was significantly greater in the high-vigor rootstocks in both soil and hydroponics. However, significantly higher VvPIP expression in non-lignified root tips compared to lignified fine roots suggest that high aquaporin activity may not be conferred evenly to an entire root system. Leaf area specific transpiration rates were greater for vines with 110R rootstock compared to 420A, and root weight normalized Kh was tightly correlated with transpiration and greatest for high vigor rootstocks. Despite the positive correlation between VvPIP expression and vigor, varied rootstock Kh in this study appears to result primarily from differences in root system biomass and to a lesser or negligible extent by differences in fine root Kh associated with aquaporin activity.