Seasonal fluctuations inVitis viniferaroot respiration in the field

Abstract

Summary• We studied the seasonal fluctuation of soil respiration (R S ), and its rootdependent (R R ) and basal (R B ) components, in a Vitis vinifera (Chardonnay) vineyard.• The R S components were estimated through independent field methods (y-intercept and trenching) and modeled on the basis of a Q 10 response to soil temperature, and fine and coarse root respiration coefficients. The effect of assimilate availability on R R was assessed through a trunk girdling treatment.• The apparent Q 10 for R R was twice that of R B (3.5 vs 1.6) and increased linearly with increasing vine root biomass. The fastest R R of fine roots was during rapid fruit growth and the fastest R R of coarse roots was immediately following fruit development. R S was estimated at 32.6 kg ha )1 d )1 (69% as a result of R R ) for the hottest month and at 7.6 kg ha )1 d )1 (18% as a result of R R ) during winter dormancy. Annual R S was low compared with other natural and cultivated ecosystems: 5.4 Mg ha )1 (46% as a result of R R ).• Our estimates of annual vineyard R S are the first for any horticultural crop and suggest that the assumption that they are similar to those of annual crops or forest trees might lead to an overestimation.

Soil Respiration Across a Disturbance Gradient in Sclerophyllous Ecosystems in Central Chile

“…Given that soil water is usually the limiting resource in semiarid environments, several authors argue that the response of soil respiration to soil temperature must depend on soil water availability (Jia et al, 2006;Rey et al, 2011). Recently, Zhang et al (2010) found that soil water content enhances the response of soil respiration to temperature, as has also been observed in irrigated agro-ecosystems in arid zones (Franck et al, 2011). Our results confirm these findings.…”

“…However, we also found that R s was strongly correlated with root biomass; root biomass increased as disturbance receded and therefore soil respiration was partly driven by root activity. It is now well accepted that the substrate supply from canopy photosynthesis exerts a strong effect on root and microbial respiration (Franck et al, 2011;Högberg et al, 2001;Luo and Zhou, 2006). Large differences in the leaf area index across disturbance conditions suggest that photosynthesis (and its integral, gross primary productivity) decreased in the series D1, D2, D3 and D4, which may have driven root activity and soil respiration in our study.…”

Flavescence dorée phytoplasma titre in field‐infected Barbera and Nebbiolo grapevines

“…Temperature stresses also affect Ca 2+ homeostasis in grapevine (Wang et al, 2004). Also, low temperatures reduce respiration rates in grapevine (Franck et al, 2011), thus reducing the production of H 2 O 2 (Foyer et al, 2009), a molecule probably involved in defence response pathways to phytoplasmas (Musetti et al, 2007). One can speculate that more severe FD symptoms in both cultivars in early and late summer assessment of 2009 may be an effect of a long-lasting stress of the plant caused by the occurrence of low winter/ spring temperatures in that year.…”

Impacts of morphological traits and temperature on fine root respiration during dormancy of Caragana korshinskii

“…Like leaves, fine roots have high physiological activity (Burton et al 2008) and they show higher respiration rates than roots with larger diameters (Dannoura et al 2006;Marsden et al 2008;Makita et al 2009Makita et al , 2012Sun and Mao 2011). Fine root respiration (R fr ) is responsible for approximately 40 % of plant total C flux (Hamilton et al 2002;Drake et al 2008;Franck et al 2011), thus precise estimates of R fr are vital to ecological research. Compared with the factors that affect respiration in other plant organs (e.g., leaves), those that influence R fr are less well understood (Franck et al 2011).…”

“…Fine root respiration (R fr ) is responsible for approximately 40 % of plant total C flux (Hamilton et al 2002;Drake et al 2008;Franck et al 2011), thus precise estimates of R fr are vital to ecological research. Compared with the factors that affect respiration in other plant organs (e.g., leaves), those that influence R fr are less well understood (Franck et al 2011).…”