Variations in seed and post-harvest residue yields and residues quality of common bean (Phaseolus vulgaris L.) as a ruminant feedstuff

• Published in: Animal feed science and technology 2018-10, Vol.244, p.42-55
• Main Authors: Dejene, Mesfin, Dixon, Rob M., Duncan, Alan J., Wolde-meskel, Endalkachew, Walsh, Kerry B., McNeill, David
• Format: Article
• Language: English
• Subjects: Common bean; East Africa; Grain legumes; Haulm; Ruminants
• ISSN: 0377-8401; 1873-2216
• DOI: 10.1016/j.anifeedsci.2018.07.017

•There were considerable variability in seed and post-harvest residues (haulm + pod wall (HPW)) yields and residues quality among genotypes.•Relationships between yields of seed and HPW were positive and strong.•There was a positive association between seed yield and HPW dry matter digestibility,•In general seed yield was not related to the nitrogen concentration.•It is possible to identify genotypes which combine high yields of both seed and HPW, and with improved HPW quality attributes. Common bean is widely grown as a food legume and the post-harvest crop residues (CR) (i.e. haulm + pod wall (HPW)) are valuable as ruminant feedstuffs. The yields and constituents indicative of nutritive value for ruminants of the HPW from a wide range of common bean genotypes (G) were examined at 4 trial sites in Ethiopia during the 2013 main cropping season to assess the extent of genetic variation among G for simultaneous improvement of both HPW attributes and seed yield. Attributes measured were seed and HPW yields and the amounts of the morphological components, their concentrations of total nitrogen (N), neutral detergent fibre (aNDFom) and acid detergent fibre (ADFom), and the dry matter digestibility (DMD). The constituents were measured using near infrared spectroscopy (NIRS) and calibrations based on a large set of reference tropical forages and CR (including common bean), and were validated against other CR reference samples. These CR quality attributes were very well predicted with R2v and RPDv ranging from 0.90 to 0.98 and 3.13–7.36, respectively. There was considerable variation in yields of HPW and seed, and in the proportions and attributes of the HPW fractions among the common bean G. Trial site means for yields of HPW and seed ranged from 0.74 to 2.54 t/ha and 0.79–2.62 t/ha, respectively while for N, aNDFom and ADFom concentrations and DMD of HPW ranged from 7.7 to 11.4 g/kg DM, 648–739 g/kg DM, 502–585 g/kg DM, and 467–570 g/kg DM, respectively. Environment (E), as represented by site, generally affected the yields of HPW and seed (P