Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Argentine → Coberturas vegetales en viñedos bajo riego localizado, respuesta fisiológica de especies herbáceas nativas a diferentes ambientes

Universidad Nacional de Córdoba (2015)

Coberturas vegetales en viñedos bajo riego localizado, respuesta fisiológica de especies herbáceas nativas a diferentes ambientes

Ferrari, Florencia N.

Titre : Coberturas vegetales en viñedos bajo riego localizado, respuesta fisiológica de especies herbáceas nativas a diferentes ambientes

Auteur : Ferrari, Florencia N.

Université de soutenance : Universidad Nacional de Córdoba

Grade : Doctor en Ciencias Agropecuarias 2015

Présentation
In water-scarce areas with high evaporative demand of the environment, such as Mendoza province in Argentina, it is essential to irrigate crops. The use of cover crops is a sustainable tool for maintaining soil structure, improving infiltration, controlling soil erosion, adding organic matter, among others benefits. Native species from arid environments are economically and environmentally superior over the exotic ones as they are adapted to low water availability conditions, as in drip irrigated vineyards ; nevertheless, there is no investigation or commercially available seeds locally. The aim of this study was to evaluate six dominant native grasses in three wine-regions (Digitaria californica, Leptochloa dubia, Nassella tenuis, Pappophorum phillippianum, Setaria leucopila and Sporobolus cryptandrus) and select the most suitable species for use as cover crops in drip irrigated vineyards. For this, (i) it was characterized the physiological behavior of six spontaneous native grass in field growing conditions (inter-row of a drip irrigated vineyard) ; (ii) it was described photosynthesis response to CO2 concentration, photosynthetically active radiation, temperature, soil water content growing in pots ; (iii) it was recorded their carbon balance and annual water consumption growing in a drip irrigated vineyard inter-row ; and finally, (iv) it was recognized the optimal conditions for germination of each species. Based on the results, the evaluated species could be used as cover crop in drip irrigated vineyards. But, D. californica, N. tenuis y P. phillippianum have advantages over other species (high biomass production, high germination, high soil coverage, opposite season cycle, lower plants, etc.). (i) In the evaluated sites had a spontaneous cover crop adapted to climb, soil and management. Species assessed are adequate to use as cover crop in drip irrigated vineyards. (ii) Mostly, C4 species would be benefit in a future climate change scenario with higher temperatures and lower availability of water for irrigation than C3 species (N. tenuis) ; although, C3 would have advantages with higher atmospheric CO2 concentration. (iii) The cover crop (native or spontaneous) recorded a carbon balance of 2.94 kg CO2 m-2 on average, while bare soil lost 0.27 kg CO2 m-2. The cover crop with native species consumed 2.6 times more water (from annual evapotranspiration) than bare soil (from annual evaporation) ; and a spontaneous cover crop (mostly composed by exotic species) consumed 3.8 times more water than bare soil. (iv) The maximum percentage of germination was : 98% for D. californica (in any evaluated temperature and light condition), 68% for P. phillippianum (with 35°C and light), 66% for L. dubia (with > 30°C and permanent darkness), 60% for S. cryptandrus (with scarified seeds and temperatures between 20 – 35°C), 50% for N. tenuis (with 25ºC and light), and 21% for S. leucopila (with scarified seeds and any evaluated condition). Key words : cover crop, vineyard, native species, gas exchange, drip irrigation.

Présentation

Version intégrale (3,43 Mb)

Page publiée le 31 août 2016, mise à jour le 3 juillet 2017