Rootstock impact on foliar symptom expression of esca on Vitis vinifera cv. Cabernet-Sauvignon

L’Albana è il vitigno a bacca bianca tradizionale delle colline della Romagna, dove é presente per più di 2.500 ha. Con le sue uve si produce il vino “Albana di Romagna”, una delle più storiche D.O.C.G. italiane essendo stata costituita nel 1987. La maggiore concentrazione di vigneti di Albana si trova nell’Imolese e nelle colline del Ravennate, ma ben conosciuta per la qualità del prodotto é anche la produzione di Bertinoro, nel Forlivese.

The use of rootstocks tolerant to soil water deficit is an interesting strategy to cope with limited water availability. Currently, several nurseries are breeding new genotypes, but the physiological basis of its responses under water stress are largely unknown. To this end, an ecophysiological assessment of the conventional 110-Richter (110R) and SO4, and the new M1 and M4 rootstocks was carried out in potted ungrafted plants. During one season, these Vitis genotypes were grown under greenhouse conditions and subjected to two water regimes, well-watered and water deficit. Water potentials of plants under water deficit down to < -1.4 MPa, and net photosynthesis (AN) <5 μmol m-2 s-1 did not cause leaf oxidative stress damage compared to well-watered conditions in any of the genotypes. The antioxidant capacity was sufficient to neutralize the mild oxidative stress suffered. Under both treatments, gravimetric differences in daily water use were observed among genotypes, leading to differences in the biomass of root, shoot and leaf. Under well-watered conditions, SO4 and 110R were the most vigorous and M1 and M4 the least. However, under water stress, SO4 exhibited the greatest reduction in biomass while M4 showed the lowest. Remarkably, under these conditions, SO4 reached the least negative stem water potential (Ψstem), while M1 reduced stomatal conductance (gs) and AN the most. In addition, SO4 and M1 genotypes also showed the highest and lowest hydraulic conductance values, respectively. Our results suggest that there are differences in water use regulation among genotypes, not only attributed to differences in stomatal regulation or intrinsic water use efficiency at the leaf level. Therefore, because no differences in canopy-to-root ratio were achieved, it is hypothesized that xylem vessel anatomical differences may be driving the reported differences among rootstocks performance. Results demonstrate that each Vitis rootstock differs in its ecophysiological responses under water stress.

Une étude conduite dans le cœur du vignoble A.O.C. angevin, sur une surface d’environ 30.000 ha, a permis de caractériser et cartographier finement (levé au 1/12.500)

Excell laboratory has initiated the development of an analytical method based on electrochemistry to evaluate the ability of wines to undergo or resist to oxidative phenomena. Electrochemistry is a powerful tool to probe reactions involving electron transfers and offers possibility of real-time measurements. In that context, the laboratory has implemented electrochemical analysis to assess oxidation state of different wine matrices but also in order to evaluate oxidative or reduced character of leaf and soil. Initially, our laboratory focused on dosage of compounds involved in responses of plant stresses and we were also interested in microbiological activity of soils. These analyses were compared with the measurement of redox potential (Eh) and pH which are two fundamental variables involved in the modulation of plant metabolism. Indeed, the variation of redox states of the plant reflects its biological activity but also its capacity to absorb nutriments. The Eh-pH conditions mainly determine metabolic processes involved in soil and leaf and our goal is to determine if this combined analytical approach will be sufficiently precise to detect biological evolutions (plant health, parasitic attack…).

In questa nota viene analizzata l’importanza della conoscenza del territorio nel funzionamento del mercato dei prodotti alimentari di qualità e nella gestione delle denominazioni di origine.
La denominazione di origine si sta affermando in tutti i mercati alimentari, dopo l’esperienza secolare maturata nel mercato del vino. Iniziative nel campo del turismo, delle produzioni ecologiche, della promozione dello sviluppo, sono collegate alla dimensione territoriale, in risposta ad un generale orientamento della domanda.