α‐Tocopherol and β‐carotene contents of forage species in a four‐cut system

Abstract

α‐Tocopherol and β‐carotene concentrations were measured in herbage of birdsfoot trefoil (Bft), red clover (Rc), white clover (Wc), timothy (Ti) and perennial ryegrass (Pr) grown in four mixtures (Bft+Ti, Rc+Ti, Rc+Pr and Wc+Pr) in a small‐plot field experiment at Foulum, Denmark, over 2 years. Plots were fertilized with cattle slurry and harvested in a four‐cut system: 30 May/7 June, 5 July/12 July, 22 August/21 August and 24 October/9 October in 2005/2006. Bft was the legume with the highest α‐tocopherol concentration in most harvests [86 mg kg−1 dry matter (DM) averaged over all harvests of 2 years], whereas mean α‐tocopherol concentrations in Wc and Rc were 37 and 34 mg kg−1 DM respectively. Bft and Wc had higher β‐carotene concentrations than Rc when averaged over harvests and years (80, 67 and 44 mg kg−1 DM in Bft, Wc and Rc, respectively; P < 0·0001). Vitamin concentrations were similar in harvests 1–3, but in most sward treatments they were considerably higher in harvest 4. No clear differences were found between years. Averaged over years and harvests, mean α‐tocopherol concentrations in timothy and perennial ryegrass were 46 and 50 mg kg−1 DM, respectively, and mean β‐carotene concentrations were 54 and 62 mg kg−1 DM. In conclusion, herbage of birdsfoot trefoil generally had higher vitamin concentrations than white or red clover, but differences between the two grass species were small and inconsistent.

Carotenoid, Tocopherol, and Phenolic Compound Content and Composition in Cover Crops Used as Forage

“…Sickel et al 18 observed an average total tocopherol concentration of 141 mg/kg DM in mountain plant species. Graulet et al 17 reported an average α-tocopherol concentration of 256 mg/kg DM in mountain plant species, whereas a concentration below 50 mg/kg DM was observed by Elgersma et al 19 and Lindqvist et al 20 in lowland areas. Concentrations of γ-tocopherols were in the range of values reported by Sickel et al 18 but lower than values observed by Graulet et al 17 Kalber et al 31 measured the tocopherol contents of buckwheat and phacelia when mixed with ryegrass and surprisingly found values 10 times lower than values obtained in this study.…”

“…Indeed, the total tocopherol concentration was not correlated with leaf proportions (r = −0.015, P = 0.92), and species with larger leaves such as crimson clover contained less tocopherol than species with small-sized leaves such as vetch. Lindqvist et al 20 explained the higher α-tocopherol content in birdsfoot trefoil compared with red clover by a slower growth rate and fewer actively growing leaves. However, in the present study, crimson clover was the plant species with the lowest tocopherol content but not the plant species with the shortest growth period.…”

“…Indeed, grasslands with lower botanical diversity have higher carotenoid concentrations, but these concentrations usually decrease with forage age, , although data suggest that carotenoid composition does not vary. Comparisons of tocopherol concentrations in fresh forages of different plant species and stages of growth have until recently yielded inconsistent results. − Current knowledge on phenolic compounds in forage is scarce. Phenolic compounds comprise a wide group of plant compounds; more than 8000 phenolic structures are known .…”

Differences in Ergocalciferol Content and Some Agronomic Characters Among Growth Stages in Six Field Pea Genotypes

“…Hay yield (t ha -1 ) for those samples were calculated by drying approximately 500 g samples at 55 °C for 48 hour followed by storage for a further day at room temperature (Ates and Tekeli, 2007;Ateş and Seren, 2020). Besides, 600 g fresh herbage samples (Lindqvist et al 2013) of the field pea genotypes were taken from each plot at all growth stages at 3 cm height from ground level before ergocalciferol analyses. Then, samples were sterilized in 2 % sodium hypochlorite solution for 15 minute and washed in distilled water three times (Bajji et al 2002;Tenikecier and Ates, 2018).…”

“…Then, samples were sterilized in 2 % sodium hypochlorite solution for 15 minute and washed in distilled water three times (Bajji et al 2002;Tenikecier and Ates, 2018). The samples in sterile plastic bag for ergocalciferol analyses were frozen (-20 °C) immediately after sterilized (Lindqvist et al 2013). The ergocalciferol contents (µg kg -1 in fresh matter (FM) basis) of freeze-dried samples were determined according to the methods described by Jäpelt et al (2011).…”