Effect of ensiling field bean, field pea and common vetch in different proportions with whole-crop wheat using formic acid or an inoculant on fermentation characteristics

Whole‐crop field bean (FB), field pea (FP) and common vetch (CV) [155, 213 and 238 g dry matter (DM) kg^?1] were ensiled in 1·5 L laboratory silos with whole‐crop wheat as mixtures of 0, 0·25, 0·50, 0·75 and 1·00 of fresh weight (FW). Silages were ensiled (i) without additive, and (ii) with formic acid (FA) (4 L t^?1) or (iii) an inoculant (Lactobacillus plantarum, 10⁶ colony‐forming units g^?1 FW) as additives. The concentrations of water‐soluble carbohydrates in herbage of whole‐crop FB, FP, CV and wheat were 93, 157, 67 and 114 g kg^?1 DM and the buffering capacities were 588, 710, 755 and 429 mEq kg^?1 DM respectively. Field bean and FP silages were mainly well preserved with low pH values and moderate fermentation losses, except for FB‐only silage without additive which had a high butyric acid concentration. Common vetch silages had higher pH values and were less well fermented compared to the silages of the other legumes. For all legumes, FA reduced ammonia‐N concentrations more effectively compared to other additive treatments. In conclusion, in FB and FP silages the use of FA or an inoculant, as additives, ensured good preservation up to a proportion of legume in the herbage of 0·75. With all legume silages, and with those containing CV, only FA, as an additive, adequately restricted protein breakdown.     

Agronomic,forage quality and economic advantages of red pea (Lathyrus cicera L.) intercropping with wheat and oat under low‐input farming

Red pea–cereal intercropping could provide animal feed with agronomic and economic advantages. The growth rate, forage yield, quality, interspecific competition and financial outcome of intercrops of red pea (Lathyrus cicera L.) with wheat (Triticum aestivum L.) and oat (Avena sativa L.) in two different seeding ratios (60:40, 80:20) were estimated. Growth rate of species was lower in the intercrops than in monocrops, especially in red pea–oat intercrops due to the strong competitive ability of oat. Red pea–oat intercrop of 60:40 produced the highest biomass (10.83 Mg/ha) and crude protein yield (1,116 kg/ha). Land equivalent ratio (LER) values were greater for the red pea with wheat (1.13) and oat 60:40 (1.09) indicating an advantage of intercropping in terms of dry‐matter (DM) yield, while red pea:oat 60:40 ranked first for LER for nitrogen yield. Aggressivity and partial actual yield loss indicated cereals as the dominant species. The highest monetary advantage index was recorded for the red pea:wheat 60:40 and the highest intercropping advantage value was recorded for the red pea:oat 80:20. In conclusion, most intercrops of red pea with wheat and oat showed significant advantages relative to their monocrops due to better DM production, resource‐use efficiency and economics under low‐input farming.     

Productivity,grazing utilization,forage quality and primary production controls of species‐rich alpine grasslands with Nardus stricta in northern Spain

Species‐rich alpine grasslands with Nardus stricta are important communities for both animal production and environmental conservation in Europe. We selected two contrasting types of Nardus grasslands (mesic and wet) within a rangeland of northern Spain and measured annual above‐ground net primary productivity (ANPP), botanical components, forage utilization and their respective seasonal patterns, during a 5‐year period. We analysed their chemical properties and recorded soil moisture and temperature in order to construct models able to explain grassland productivity. Mean annual ANPP of mesic Nardus grassland was about half (216 g DM m^?2 year^?1; ±29·8 s.e.) that of the wet grassland (406 g DM m^?2 year^?1; ±54·3 s.e.), with significant intra‐ and interannual variability. Mesic grassland, with a more important contribution of forbs and legumes over graminoids in its botanical composition, was the preferred forage source of grazing livestock and showed better chemical properties in spring and early summer. In summer and autumn, wet grassland had a higher utilization owing to its ability to maintain high biomass production. This was partially explained by soil moisture, a limiting factor of mesic grassland productivity. Our results provide new and relevant information on key aspects of species‐rich alpine Nardus grasslands, potentially useful for the definition of management options for these habitats of priority conservation.     

Self‐regeneration of hairy vetch (Vicia villosa Roth) as affected by seedling density and soil tillage method in a semi‐arid agroecosystem

Vicia villosa Roth is a forage legume with the capability for biological N fixation and natural reseeding, which could contribute to sustainability in semi‐arid regions. This study aimed to determine (i) the relationship between vetch density, seed production and spontaneous seed dispersal; (ii) the impact of the post‐dispersal tillage treatment over the soil seedbank dynamics; and (iii) potential predation of the seedbank by feral pigeons. A density range between 50 and 200 plants m^?2 did not influence seed production or seed dispersal. Shallow disc tillage (SDT) clearly favoured self‐regeneration, resulting in higher amount of emerged seedlings during autumn compared to no tillage (NT). Based on observed emergence data, the percentage of emerged seedlings under SDT and NT were 38 and 6% of the seedbank, respectively, during 18 months after plot harvest. The lowest emergence values registered under NT could be associated with higher pressure from natural predators, soil‐borne pathogens, seed decay by ageing and false breaks. The feral pigeon (Columba livia var.) might be considered the main cause of vetch seedbank depletion in this study. Under controlled conditions, a single pigeon is able to consume, on average, between 184 and 768 seeds per day, depending on seed exposure and alternative food sources availability.