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

Accueil du site → Projets de développement → Projets de recherche pour le Développement → 2015 → USING HALOPHYTIC PLANTS TO IMPROVE FOOD SECURITY AND ENVIRONMENTAL QUALITY IN DRYLAND ECOSYSTEMS

United States Department of Agriculture (USDA) 2015

USING HALOPHYTIC PLANTS TO IMPROVE FOOD SECURITY AND ENVIRONMENTAL QUALITY IN DRYLAND ECOSYSTEMS

FOOD SECURITY - DRYLAND ECOSYSTEMS

United States Department of Agriculture (USDA) Research, Education & Economics Information System (REEIS)

Titre : USING HALOPHYTIC PLANTS TO IMPROVE FOOD SECURITY AND ENVIRONMENTAL QUALITY IN DRYLAND ECOSYSTEMS

Identification : NEV05294

Pays : Etats Unis

Durée : Jul 1, 2015 à Jun 30, 2019

Mots clés : food security ; salinity ; marginal lands ; biofuel ; forage

Partenaire : UNIVERSITY OF NEVADA RENO,NV 89557

Objectifs
The proposed project's long-term goal is to enhance food security and environmental quality by increasing agricultural production on marginalized saline croplands through the use of halophytic crops. For the purposes of this proposal, we define "marginal lands" as those that have limited options for maintaining or increasing crop production due to soil salinity constraints (CGIAR 1999).

Descriptif
We will investigate these hypotheses through the following tasks:1. Select field plots at Main Station Field lab : Following a preliminary soil survey (see Task 3), we will select field plot locations and construct an irrigation system to them on non-saline and salt-affected lands on the Main Station Farm.2. Planting of halophytic plants at field sites : Four halophytes will be planted : 1) a perennial shrub, Rubber rabbitbrush (Chrysothamnus nauseosus (Pallas) Britt., 2) a perennial grass, AC Saltlander green wheatgrass (Pseudoroegneria spicata x Elytrigia repens), 3) a perennial forb, curlycup gumweed (Grindelia squarrosa (pursh) Dunal), and 4) an annual forb, glasswort (Salicornia europaea). These halophytes represent potential sources of biofuel (rabbitbrush, gumweed), quality livestock forage (AC Saltlander green wheatgrass), and a vegetable product for livestock forage source and direct human consumption (glasswort).The experimental design for the field trials includes halophytes planted with the following treatments:Non-saline soil with irrigation at 100% of evapotranspiration (ET)Saline soil with irrigation at 100% of ET plus appropriate leaching required to leach salts below rooting depth prior to the growing seasonSaline soil with irrigation at 100% of ET with no leachingSaline soil with irrigation at 75% of ET with no leachingSaline soil with irrigation at 50% of ET with no leachingThe ET amount considered 100% of ET will be the real-time reference ET obtained from the Main Station Field lab's on-site weather station. The experimental design will be a randomized complete block with 4 replications. The seeded species will be whole experiments and the irrigation levels will be sub-plots.3. Sampling and analysis of plants, soil, and water for salt ions and nutrient content:a. Soil sampling and analysis : We will assess effects of halophytes on salt accumulation by measuring soil and soil solution chemistry throughout the project. At project start, bulk density and soil texture will be measured for each subplot. Soil salt profiles will be determined at the start and end of the project while soil solution chemistry will be monitored on a monthly basis depending on soil moisture conditions. In addition, previous work indicated the APEX model was sensitive to soil organic carbon content and soil albedo, both of which will be measured at the start and end of the study in each plot.b. Plant sampling and analysis : At completion of the first growing season, perennial plant species (rabbitbrush, AC Saltlander green wheatgrass, curlycup gumweed) will be sampled to determine initial establishment and survival by irrigation treatment. The evaluation will consist of determining plant density and height along the seeded rows. The annual herb (glasswort) will be harvested and weighed to determine biomass production by irrigation treatment. During the remaining years of the project all plant species will be harvested annually, with biomass determined for each species and irrigation treatment. Harvested plants will be analyzed for the fraction of phosphorus and fraction of water in the crop yield. A subset of plants will be sampled monthly to measure parameters for modeling including leaf area index, maximum root depth, above and below-ground biomass, and crop height.4. In vitro digestibility experiments to assess nutrient availability of halophytes for ruminant animals : Digestibility experiments will be performed on harvested halophytes. The dual-flow continuous culture system is an in vitro technique developed by Hoover et al. (1976) that simulates rumen digestion in which different feeds and artificial saliva are mixed with fresh rumen fluid. In the modern version of this system (Soder et al. 2013), temperature, anaerobiosis, and flow rates are tightly controlled. This technique has been widely used to evaluate the effect of complete diets and individual feed ingredients on ruminal digestion, fermentation, microbial protein synthesis, and nutrient flow (Hristov et al. 2012).

Présentation USDA

Page publiée le 8 octobre 2015, mise à jour le 13 octobre 2017