Evaluating alternative fertilisers and their impact on yield and quality of spelt and rye under different management systems

Abstract

Spelt (Triticum spelta) and rye (Secale cereale) are low-input cereals attracting growing interest as sustainable and nutritionally beneficial alternatives to modern wheat (Triticum aestivum). The effects of fertiliser type, fertiliser rate and variety choice on spelt and rye crop yield and quality were assessed in single-site field trials in the 2014-15 and 2015-16 seasons. The multi-factorial trials at Nafferton Farm in Northumberland evaluated four varieties (including both landraces and modern varieties) each of spelt and rye grown with four fertiliser N input types (farm yard manure compost, cattle slurry, mineral N and biogas digestate) at two rates of N (50 and 100 kg/ha). Farmer Participatory trials took place across 10 farms (4 conventional and 6 organic) in Northeast England during the 2016-17 and 2017-18 seasons. The same four varieties of spelt and rye were evaluated under individual farm management systems and two fertiliser input types (biogas digestate and ‘typical’ farm inputs). Data collection was supported by the creation of an online database and web platform for data recording and subsequent statistical analysis. In the Nafferton field trials, biogas digestate was the highest yielding fertiliser treatment for spelt (3.64 t/ha) while digestate (5.27t/ha) and mineral N (5.21 t/ha) were the highest yielding N treatments for rye. Yields were significantly higher for both crops in 2015 (spelt: 3.60t/ha; rye: 5.74t/ha) compared to 2016 (spelt: 2.86 t/ha; rye: 3.74t/ha) due to higher solar radiation from April to July. The highest yielding varieties were the spelt landrace Oberkulmer Rotkorn (3.74 t/ha) and the modern rye variety Elias (5.59 t/ha). Rye was not susceptible to foliar disease but yellow rust was present in the spelt and was significantly higher in the spelt x wheat cross Filderstolz. Grain quality parameters (Hagberg Falling Number, specific weight and protein content) varied significantly by variety and year. In the Farmer Participatory trial, conventional farms (spelt: 3.15t/ha; rye: 3.68t/ha) produced higher yields than organic farms (spelt: 2.18t/ha; rye: 2.23t/ha). Biogas digestate inputs produced higher yields (spelt: 2.68t/ha; rye: 3.70t/ha) than typical farm inputs on both organic and conventional farms. Oberkulmer Rotkorn (2.72t/ha) and Elias (3.76t/ha) were the highest yielding spelt and rye varieties in the multi-site trial. Across both the factorial field trial and Farmer-Participatory trial, the same spelt (Oberkulmer Rotkorn) and rye (Elias) varieties produced the highest yields while biogas digestate produced higher yields than all other fertiliser inputs except mineral N.