Organic recycled mulches in sustainable viticulture: assessment of spontaneous plants communities and weed coverage

Organic recycled mulching has become an interesting strategy for developing more efficient and sustainable viticulture management. This work aimed to analyse the effect of three different organic mulches [straw (S), grape pruning debris (GPD) and spent mushroom compost (SMC)] and two traditional soil management techniques [herbicide and inter-row tillage] on weed control and the spontaneous plant communities presence in the vine-line. SMC and herbicide were the treatments with the highest and the lowest weed cover percentage respectively. Inter-row tillage had a delayed weed emergence at the beginning of the vine vegetative cycle but finally, it reached maximum values nearby SMC. GPD and S had similar effects on weed emergence, reaching up to 23% and 31% of the maximum coverage values respectively. An amount of 28 herbaceous species were identified, some of them very isolated and occasional. Principal component analysis (PCA) showed specific species-treatment associations, especially for inter-row tillage and SMC treatments. The different soil management techniques had a clear effect on weed coverage and plant species communities. This study provides interesting information about how organic recycled mulching influences spontaneous plant biodiversity and weed coverage control

In vitro interactions between Armillaria sp. and Trichoderma sp. collected from mushroom crop residues

Armillaria mel/ea (Agaricales: Physalacriaceae) is a fungus naturally occurring in the soil, which may penetrate the grapevines' roots, causing their death in the long term. Many chemical products have been tested to manage this fungus with limited success. Nowadays, uprooting and non-prolonged cultivation is the only field-allowable and effective solution. Trichoderma is a well-known fungus used as a biocontrol agent. However, it is also known to be a contaminating fungus far the cultivation of mushrooms (Agaricus sp.). We hypothesized that T. Harzianum from contaminated mushroom cultivation is an effective biological control agent of A. mellea in vitro and could be used as a treatment in the vineyard. In this sense, a circular economic model would be favored in which, on the one hand, the waste reuse from mushroom cultivation would be encouraged, and on the other hand, an effective and sustainable solution would be proposed to combat sorne fungal diseases. To accomplish this, field strains of T. Harzianum and A. mellea were isolated on Malt Extract Agar (MEA). Dual confrontation tests on Patato Dextrose Agar (PDA) plates were performed to evaluate the inhibitory effect of the T. harzianum strain on A mellea. Far this purpose, A. mellea was plated 14 days befare T. harzianum. The two fungi were also individually cultivated as positive controls. AII plates were kept at 25ºC throughout the experiment. We observed that T. harzianum inhibited the in vitro growth of A. mel/ea. Specifically, the A. mel/ea growth stopped when both fungi met, while T. harzianum continued to grow above A. mel/ea. The results obtained support our hypothesis of the potential of T. harzianum as a biocontrol agent far A. mel/ea. However, it must be validated in field experiments. Future research will facus on analyzing whether mushroom crop residues infected with T. harzianum could be reused as an organic mulch treatment against A. mellea in the vineyard

Effects of organic mulches on the soil environment and yield of grapevine

Farming management practices aiming at conserving soil moisture have been developed in arid and semiarid-areas facing water scarcity problems. Organic mulching is an effective method to manipulate the crop-growing microclimate increasing crop yield by controlling soil temperature, and retaining soil moisture by reducing soil evaporation. In this sense, the effectiveness of different organic mulching materials (straw mulch and grapevine pruning debris) applied within the row of a vineyard was evaluated on the soil and on the vine in a Tempranillo vineyard located in La Rioja (Spain). Organic mulches were compared with a traditional bare soil management technique (based on the use of herbicides to avoid weed incidence). Mulching coverages favourably influenced the soil water retention throughout all the grapevine vegetative cycle. However, the soil-moisture variation was not the same under different mulching materials, being the straw mulch (SM) the one that retained more water in comparison with grapevine pruning debris (GPD) based-cover. The changes of soil moisture in the upper surface layer (010 cm) were highly dynamic, probably due to water vapour fluxes across the soil-atmospheric interface. However, both, SM and GPD reduced these fluctuations as compared with bare soils. A similar trend occurred with soil temperature. Both organic mulches altered soil temperature in comparison with bare soil by reducing soil temperature in summer and raising it in winter. Moreover, the same buffering effect for the temperature on the covered soil also remains in the deeper layers. To conclude, we could see that organic mulching had a positive impact on soil-moisture storage and soil temperature and the extent of this effect depends on the type of mulching materials. These changes led to higher rates of photosynthesis and stomatal conductivity compared to bare soils, also favouring crop growth and grape yields

Vertical cordon training system enhances yield and delays ripening in cv. Maturana Blanca

The growing interest in minority grape varieties is due to their potential for adaptation to global warming and their oenological capabilities. However, the cultivation of these varieties has often been limited due to their low economic efficiency. One such example is Maturana Blanca, a recently recovered and authorized minority grape variety in the DOCa Rioja region, known for its remarkable oenological potential but low productivity. This study aimed to increase the yield of Maturana Blanca by implementing the vertical cordon training system, which allowed for a higher number of buds per plant and an increased cluster count per vine. A comparative analysis was conducted between two training systems, head-trained (HT) and vertical cordon (VC), along with two irrigation regimes, rainfed and irrigation at 30 % of ET0. The results indicated that the training systems had a more significant impact on production and fruit composition compared to the irrigation treatment. Specifically, the VC system increased yield by ranging from 60% to 80% when compared to the HT system. Additionally, the higher productivity observed in the VC vines led to more optimal source-sink ratios, resulting in a tendency toward delayed ripening. This research provides valuable insights into viticultural practices to improve the productivity and quality of minority varieties such as Maturana Blanca and contributes to a broader understanding of sustainable viticulture and biodiversity preservation in the face of climate change. Moreover, our findings have significant implications to promote the cultivation and valorization of this minority grape variety adapted to semi-arid climates as an adaptation measure to counteract the challenges posed by global warming