The International Septoria Observation Nursery (earlier Septoria Monitoring Nursery – SMN) is a single replicate nursery that contains diverse spring bread wheat (Triticum aestivum) germplasm adapted to ME2 (High rainfall environment) and ME4 (Low rainfall, semi-arid environment) with total 50-100 entries and white/red grain color.
CIMMYT annually distributes improved germplasm developed by its researchers and partners in international nurseries trials and experiments. The High Rainfall Wheat Yield Trial (HRWYT) contains very top-yielding advance lines of spring bread wheat (Triticum aestivum) germplasm adapted to high rainfall, Wheat Mega-environment 2 (ME2HR).
The Acid-Soils Wheat Screening Nursery (ASWSN) contains spring bread wheat germplasm adapted to areas affected by low pH that are predominately in Brazil, the highlands of central Africa, and the Himalayas; the total estimated area is close to 2 million hectares. Disease and stress problems are similar to ME2. However, aluminum and manganese toxicities, plus phosphorus deficiency, are major constraints to production. Red grain is generally preferred, except in the Himalayas. High-level quality is demanded, especially in Latin America.
The Elite Spring Wheat Yield Trial (ESWYT) is a replicated yield trial that contains spring bread wheat (Triticum aestivum) germplasm adapted to Mega-environment 1 (ME1) which represents the optimally irrigated, low rainfall areas. Major stresses include leaf, stem and yellow rusts, Karnal bunt, and lodging. Representative areas include the Gangetic Valley (India), the Indus Valley (Pakistan), the Nile Valley (Egypt), irrigated river valleys in parts of China (e.g. Chengdu), and the Yaqui Valley (Mexico). This ME encompasses 36 million hectares spread primarily over Asia and Africa between 350S -350N latitudes. White (amber)-grained types are preferred by consumers of wheat in the vast majority of the areas. It is distributed to upto 200 locations and contains 50 entries.