Effect of Location, Year and Variety on Winter Cereal Forage Yield and Quality in the Southern Plateau of the Spain

The objective of this research was to study the production and quality of forage at three different times of the year (April, June and July) of six winter cereals in the southern plateau of the Iberian Peninsula. The cereals studied were Triticale (xTriticosecale wittm) cv. "Tritano", Oat (Avena sativa L.) cv. "Prevision" and cv. "Saia; Rye (Secale cereale L.) cv. "Giganton", Barley (Hordeum vulgare L.) cv. "Cameo" and cv. "Albacete". The study was carried out in three different locations and over three successive years of harvesting. The three variables considered were location, year and cereal. The % dry matter (DM), % crude protein (CP), % acid detergent fiber (ADF), % neutral detergent fiber (NDF) and % ash content were determined for the three sampling periods and the quality was calculated in milk forage units (MFU/kg DM), the production in kg DM/ha, MFU/ha and kg CP/ha. In all three sampling periods the quality of the cereals was significantly influenced only by the year and by species. However, for production of dry matter (kg DM/ha), milk forage units (MFU/ha) and gross protein (kg CP/ha) all three variables were of significant influence as were their interactions. In the April sampling, the species which showed a significantly higher production ($p{\leq}0.05$) was rye (1,693 kg DM/ha), which, along with its forage quality (16.56% CP, 0.886 MFU/kg DM) meant that the same occurred in MFU/ha and kg CP/ha. Significant differences between species were also found for the June sampling. The most productive cereal was again rye with 2,656 kg DM/ha, although its sharp fall in forage quality meant that barley cv Albacete (2,513 kg DM/ha) returned the highest production in forage units (1,934 vs. 1,951 MFU/ha) and barley cv. Cameo (2,413 kg DM/ha) in gross protein production (242 vs. 264 kg CP/ha). The significantly highest cereal production for July was barley cv. Albacete (4,923 kg DM/ha, 9.11% CP 0.722 MFU/kg DM). As a consequence of the results, we conclude that from the viewpoint of nutritional quality and production, rye is the most suitable for use in early spring in whatever year and location. However, barley cv. "Albacete" is the most appropriate for utilisation in later spring or early summer.