32 I EUROPEAN SEED I EUROPEAN-SEED.COM Photo provided by DLF Salt Tolerance - WATER QUALITY FOR IRRIGATION OF ALFALFA HAY All water used for irrigation contains some dissolved salts and 1 ha foot of water (the amount of water covering 1 ha 30 cm deep) weighs approximately 3090 tons. Therefore 1ppm of salt in 1 ha foot of water weighs a little over 3 kilogram. This means that one ha-foot of water containing only 735ppm (EC=1.15mS/cm) carries 2.47 ton of salt. Many growers apply well over 1 meter of irrigation water per year to produce a crop of alfalfa hay. In other words, they apply 8.6 – 9.9 tons of salt on every ha. every year if that water has an EC (Electrical Conductivity) of only 1.15mS/cm. One of the hazards of irrigated agriculture is the possible accumulation of soluble salts in the root zone. Some plants can tolerate more salts than others, but all plants have a maximum tolerance. Where ample water and deep drainage is used to remove excess salt from the root zone, the salt level in the saturation extract is about 1.5 times that of the irrigation water. Where water is used more sparingly, there may be three times as much salt accumulated in the plant root zone. Leaching and drainage are critical over time. Scientific data show approximately what a grower of alfalfa hay can expect when using increasing amounts (EC) of salt in irrigation waters. This data was developed using alfalfa varieties NOT developed for salt tolerance, but are very useful in general. The data gives the required percentage of additional water required for leaching salts (LR%) from the root zone in order to not increase the soil salt content, and salt (EC) content expected to reduce hay yields by: 0%, 10%, 25%, 50% and the point of no growth at all. Crop 0% 10% 25% 50% NO GROWTH Alfalfa Hay ECw 1.3 2.2 3.6 5.9 10.3 LR% 4% 7% 12% 19% — collaborations and partnerships in Europe and other areas of the globe allowing us to move quickly to address grower concerns and needs for all dormancies.” WHAT’S IN THE PIPELINE? “We also have an ETS approved transgenic program, a gene edit- ing / NBT program, as well as a broad conventional breeding pro- gram.” says Gardner. “Our European program focuses on lodging tolerance and forage quality. And we are currently using marker assisted selection and utilizing advance statistical designs on a regular basis.” Cernoch mentions that their new breeding program offers commercial varieties that are recommended for both forage and dehydration on the official GEVES list in France. “The varie- ties provide top yield, high protein, good lodging resistance and improved pest and disease tolerance. DLF also offers specialised lucerne varieties with good features in yield and establishment under sub-optimal conditions, allowing growth of lucerne on soils where it usually does not belong“. As a legume, alfalfa can satisfy its nitrogen needs through a naturally occurring symbiotic relationship with bacteria called rhizobia in the soil. This invaluable trait removes the need to use additional nitrogen fertilizer inputs to support plant growth. Recent research is trying to unlock this species’ genome. Understanding the genome sequence could lead to alfalfa plants with increased ability to survive in stressful environments such as drought and animal grazing. It could also produce higher bio- mass yields when baled as hay, extend its growing season, and adapt better to different soil types and nutrient levels. Background information on the initial Medicago truncatula research is available at http://www. noble.org/Global/news/annualreport/2011/annu- alreport.pdf