Ecosystem services in vineyard landscapes: a focus on aboveground carbon storage and accumulation.

BACKGROUND: Organic viticulture can generate a range of ecosystem services including supporting biodiversity, reducing the use of conventional pesticides and fertilizers, and mitigating greenhouse gas emissions through long-term carbon (C) storage. Here we focused on aboveground C storage rates and accumulation using a one-year increment analysis applied across different winegrape varietals and different-aged vineyard blocks. This produced a chronosequence of C storage rates over what is roughly the productive lifespan of most vines (aged 2-30 years). To our knowledge, this study provides the first estimate of C storage rates in the woody biomass of vines. Additionally, we assessed C storage in wildland buffers and adjacent oak-dominated habitats over a 9-year period. RESULTS: Carbon storage averaged 6.5 Mg/Ha in vines. We found the average annual increase in woody C storage was 43% by mass. Variation correlated most strongly with vine age, where the younger the vine, the greater the relative increase in annual C. Decreases in C increment rates with vine age were more than offset by the greater overall biomass of older vines, such that C on the landscape continued to increase over the life of the vines at 18.5% per year on average. Varietal did not significantly affect storage rates or total C stored. Carbon storage averaged 81.7 Mg/Ha in native perennial buffer vegetation; we found an 11% increase in mass over 9 years for oak woodlands and savannas. CONCLUSIONS: Despite a decrease in the annual rate of C accumulation as vines age, we found a net increase in aboveground C in the woody biomass of vines. The results indicate the positive role that older vines play in on-farm (vineyard) C and overall aboveground accumulation rates. Additionally, we found that the conservation of native perennial vegetation as vineyard buffers and edge habitats contributes substantially to overall C stores. We recommend that future research consider longer time horizons for increment analysis, as this should improve the precision of C accumulation rate estimates, including in belowground (i.e., soil) reservoirs.

Wine Yeast Terroir: Separating the Wheat from the Chaff-for an Open Debate.

Wine terroir is characterized by a specific taste and style influenced by the cultivar of the fermented grapes, geographical factors such as the vineyard, mesoclimate, topoclimate, and microclimate, soil geology and pedology, and the agronomic approach used. These characteristics together define the concept of "terroir". Thus, regional distinctive flavors in wine have been the subject of many studies aimed at better understanding the link between the wine and the vineyard. Indeed, the identification of key environmental elements involved in the regional variation of grape and wine quality characteristics is a critical feature for improving wine production in terms of consumer preference and economic appreciation. Many studies have demonstrated the role of abiotic factors in grape composition and consequently in wine style. Biotic factors are also involved such as grape microbial communities. However, the occurrence and effects of region-specific microbiota in defining wine characteristics are more controversial issues. Indeed, several studies using high throughput sequencing technologies have made it possible to describe microbial communities and revealed a link between grape must and soil microbial communities, and the geography of the territory. Based on these observations, the concept of "microbial terroir" emerged. However, this concept has been subject to contradictory studies. The aim of this opinion article is to take a step back and examine in perspective the concept of microbial terroir, by comparing numerous data from different studies and providing arguments in favor of or against this concept to stimulate discussion and point out that experimental research is still needed to study the contribution of this assembly of microorganisms to the final product and to support or refute the concept.

A New Alien Invasive Longhorn Beetle, Xylotrechus chinensis (Cerambycidae), Is Infesting Mulberries in Catalonia (Spain).

In this paper, the invasion of a new alien beetle species to Europe, the longhorn Xylotrechus chinensis (Chevrolat) (Cerambycidae), originating from East Asia, is revealed. It has settled in Catalonia (Spain), occupying at present an area of at least 44.1 km², where it has been shown to severely infest (ca. 10 to 45%) and eventually kill mulberry trees in private and public grounds. The main objective of this study was to evaluate its impact and provide new significant insights into its life history, seasonality, reproductive capacity (females produce an average of 83.4 ± 9.02 eggs) and the type of damage produced to mulberries. Such damage was thoroughly described to facilitate inspection by others. At least in laboratory conditions, X. chinensis has not used common grape vines as an alternative hostplant. Both plants, mulberries and grape vines, are important in Catalonia and Spain, the former providing shade and ornament to many streets and avenues, and the latter having great economic significance in Mediterranean wine production areas. Possible control methods to hinder its spread are suggested and one local wasp, Stephanus serrator (Stephanidae), was identified as a likely parasitoid. We believe the risk of this beetle widely spreading in Europe is very real.

Diagnosis of Lobesia botrana (Lepidoptera: Tortricidae) Using Real-Time PCR.

A real-time PCR assay is reported for identification of Lobesia botrana (Denis and Schiffermüller) collected in California. This assay multiplexes two independent TaqMan probe systems in a single reaction tube to reduce handling time and sample exposure to environmental contaminants. One probe system targets a segment of DNA located in the internal transcribed spacer region 2 (ITS2) that is present in the L. botrana genome but absent in native North American Tortricidae. The second probe system serves as a control for DNA quality by targeting a segment of the 18S rDNA gene that is conserved in L. botrana and all of the tested nontarget species. The assay successfully diagnosed 70 Lobesia botrana specimens and 95 nontarget specimens. No false-positive or false-negative results were observed supporting its application for identification of this pest in California.

CLAVATA3-like genes are differentially expressed in grape vine (Vitis vinifera) tissues.

The CLAVATA3 (CLV3)/endosperm surrounding region [(ESR) CLE] peptides function as intercellular signaling molecules that regulate various physiological and developmental processes in diverse plant species. We identified five CLV3-like genes from grape vine (Vitis vinifera var. Pinot Noir): VvCLE 6, VvCLE 25-1, VvCLE 25-2, VvCLE 43 and VvCLE TDIF. These CLV3-like genes encode short proteins containing 43-128 amino acids. Except VvCLE TDIF, grape vine CLV3-like proteins possess a consensus amino acid sequence known as the CLE domain. Phylogenic analysis suggests that the VvCLE 6, VvCLE25-1, VvCLE25-2 and VvCLE43 genes have evolved from a single common ancestor to the Arabidopsis CLV3 gene. Expression analyses showed that the five grape CLV3-like genes are expressed in leaves, stems, roots and axillary buds with significant differences in their levels of expression. For example, while all of them were strongly expressed in axillary buds, VvCLE6 and VvCLE43 expression prevailed in roots, and VvCLE25-1, VvCLE25-2 and VvCLE TDIF expression in stems. The differential expression of the five grape CLV3-like peptides suggests that they play different roles in different organs and developmental stages.