• Authors:
    • Slepetiene, A.
    • Slepetys, J.
  • Source: Grassland farming and land management systems in mountainous regions. Proceedings of the 16th Symposium of the European Grassland Federation
  • Year: 2011
  • Summary: The main objective of the current study was to evaluate the effects of six legume species ( Trifolium pratense, Medicago sativa, Trifolium repens, Galega orientalis, Medicago lupulina, Trifolium resupinatum) ploughed down as green manure, on the seed yield of timothy ( Phleum pratense) and meadow fescue ( Festuca pratensis). Legumes were undersown into barley. In the first year of production legumes were chopped and ploughed down for green manure in June. The sown timothy and meadow fescue were used for organic seed for three years. Although T. resupinatum grew well in the year of sowing it completely disappeared after winter. Based on 3-year mean production data, the highest timothy and meadow fescue seed yield was obtained after ploughing down a mixture of three legumes ( T. pratense+ M. sativa+ T. repens). Seed yield increased by 27.8-33.1%. Ploughed-down pure legumes (except G. orientalis) gave a lower but significant increase in seed yield. Having ploughed down legumes, the positive effect on organic seed was more substantial in the second and third years of production.
  • Authors:
    • Clark, H.
    • Molano, G.
    • Muetzel, S.
    • Hoskin, S.
    • Sun, X.
  • Source: Animal Feed Science and Technology
  • Volume: 166/167
  • Year: 2011
  • Summary: Published reports of CH 4 yields as g CH 4/kg dry matter (DM) intake suggest that emissions from sheep fed fresh forage chicory ( Cichorium intybus) are about 30% lower than from those fed fresh ryegrass. In this study, 2 year old wethers (16; 543.8 kg liveweight) were fed either mature chicory or perennial ryegrass at 1.3 times maintenance metabolisable energy requirements in the late spring/early summer of 2009. Methane emissions were determined using individual animal respiration chambers. Feeds differed in their chemical composition with chicory containing 856 g/kg organic matter (OM), 117 g/kg crude protein (CP) and 281 g/kg neutral detergent fibre (aNDF), whereas ryegrass contained 916 g/kg OM, 85 g/kg CP and 499 g/kg aNDF. The DM intake was similar for both forages at 0.76 kg/d, and CH 4 yields did not differ between forages being 22.8 and 23.8 g CH 4/kg DM intake for chicory and ryegrass, respectively. In vitro incubations of chicory and perennial ryegrass in the vegetative or mature states had similar CH 4 yields. Despite large differences in chemical composition, especially aNDF, chicory and ryegrass had similar CH 4 yields in vitro and in vivo. Chicory is not a viable alternative to perennial ryegrass for mitigating CH 4 in pastoral based sheep production systems.
  • Authors:
    • Mielniczuk, J.
    • Vezzani, F. M.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 35
  • Issue: 1
  • Year: 2011
  • Summary: Soil functions and quality are closely linked to soil structure. The effect of management practices on the recovery of the aggregation of a physically degraded soil was studied based on the distribution of water-stable aggregates and single particles (diameter classes 9.51-4.76, 4.76-2.00, 2.00-0.25, 0.25-0.053, <0.053 mm) and carbon stock (C) in the surface layer (0-7.5 cm) of a Paleudult in the Central Depression region of the state of Rio Grande do Sul, Brazil, under different management systems. The following systems were evaluated in experimental plots after 17 years: soil without plants and without tillage (fallow); no-till Lablab purpureus and maize ( Zea mays) (Lablab/m); no-till Cajanus cajan (pea/m) and maize; perennial pasture of Digitaria decumbens (Pangola grass). The following systems were evaluated after 15 years: conventional tillage and no-till Avena strigosa and maize (CT a/m and NT a/m, respectively) Avena strigosa+ Vicia sativa and maize+ Vigna unguiculata (CT av/μ and NT av/mu, respectively). A conventionally tilled area was also evaluated after 30 years of grain cultivation (crop) and native grassland (NGr), representing the degraded state and the native ecosystem of this soil, respectively. Undisturbed soil samples collected in two seasons (September 1999 to September 2000) were evaluated in six replications per management system. Data were analyzed by ANOVA and Tukey's test (5%) to detect differences between management systems. In the NGr, 76.4% of the soil aggregates consisted of 63.8% macroaggregates and of 23.6% of single particles, and a C stock of 20.0 Mg ha -1. The agricultural use with intense soil tillage and low residue application (crop) reduced the proportion of soil aggregates to 49.9% and raised single particles to 50.1%, while the C stock decreased to 11.8 Mg ha -1. From this condition, 15 years of the untilled system with greater diversity of plant species and high residue application (NT av/mc) raised the proportion of soil aggregates to 70.7% and of macroaggregates to 53.5%. Perennial pasture (Pangola) increased the proportion of soil aggregates to 74.1% and of macroaggregates to 61.8%, equaling NGr. The systems NT av/mc, pea/m and Lablab/m recovered C stocks to the level of NGr. Although Pangola had the highest soil aggregation rates, the C stock was lower than in the said systems, emphasizing the positive action of a dense root system in the recovery of soil aggregation.
  • Authors:
    • Miller, P.
    • Lawrence, R. L.
    • Watts, J. D.
    • Montagne, C.
  • Source: Climactic Change
  • Volume: 108
  • Issue: 1/2
  • Year: 2011
  • Summary: A pilot cropland carbon sequestration program within north central Montana has allowed farmers to receive carbon credit for management adjustments associated with changing from tillage-based agricultural systems to no-till. Carbon credit can also be obtained by adopting conservation reserve, where cropland is planted into perennial vegetation. Summer fallowing is also considered within the crediting process as credit is not given in years that a field is left un-vegetated. The carbon sequestration program has been advocated as a means to mitigate climate change while providing an added source of income for Montana farmers. There is lack of data, however, pertaining to the percentage of lands within this region that have not converted to no-till management, lands under certain crop intensities (e.g. those that are cropped every growing season vs. those that use a fallow-crop-fallow system), or cropland that have converted to perennial vegetation outside of the popular Conservation Reserve Program. Data is also sparse concerning the amount of soil organic carbon that might be sequestered given a conversion to no-till or conservation reserve. This study established regional percentage estimates of cropland under no-till, various degrees of crop intensity, and conservation reserve within north central Montana. Literature-based carbon sequestration estimates were used to generate carbon gain data associated with the conversation to no-till and to conservation reserve. These estimates were then applied to the area-based cropland statistics to estimate potential regional carbon sequestration associated with these management changes.
  • Authors:
    • Li, H.
    • Cheng, J.
    • Zhang, J.
    • Yue, T.
    • Xi, Z.
  • Source: Scientia Agricultura Sinica
  • Volume: 44
  • Issue: 11
  • Year: 2011
  • Summary: Objective: In this paper, the relationship between soil quality and soil biological characteristics such as soil microorganism quantity and soil enzymatic activity was studied in the intercropping system of vineyard, in order to illustrate the function of soil biological characteristics as bio-indicators of soil fertility. Method: Three such cover crops, two perennial legumes (white clover and alfalfa) and a perennial gramineous grass (tall fescue) were sown in vineyard. Soil microorganism quantity, soil enzymatic activities and soil nutrient content were analyzed and compared with that in soil cultivation. [Result] Most detected soil microorganism quantity and soil enzymatic activity, soil organic matter were increased under cover crop treatments, compared to clean tillage, tall fescue treatment decreased urease and sucrase activity. White clover and alfalfa treatments significantly increased the contents of hydrolyzable N, total N and available K, and tall fescue decreased them, while the activated organic P in tall fescue treatment was more effectively than that in white clover and alfalfa treatments. Correlation analysis indicated that soil organic matter, total N, hydrolyzable N, total P, available K showed significant or very significant positive correlation with 10 soil biological characteristic factors such as bacteria, fungi, actinomyces, azotobacter, cellulose-decomposing bacteria, urease, phosphatase, amylase, sucrase, and cellulose. The catalase activity was no significant correlation with all the soil nutrient contents, and the total K content was no significant correlations with all the soil biological characteristic factors. The soil pH in this experiment was negatively correlated with soil biological properties. Conclusion: Cover crops in the inter-rows of vineyard increased soil microorganism quantity, soil enzymatic activity and soil nutrient content, white clover and alfalfa treatments were better than tall fescue. There are significant correlations between soil biological characteristics and nutrients, and soil biological indexes could reflect the changes of soil quality.
  • Authors:
    • Foster, A.
    • Malhi, S.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 42
  • Issue: 19
  • Year: 2011
  • Summary: Annual cover crops compete with underseeded perennial forages for light, moisture, and nutrients and may suppress their establishment and growth. Field experiments were established in 2000 and 2001 at Nipawin and in 2002 and 2003 at Melfort in northeastern Saskatchewan to determine the effects of seeding rates of cover crops of oat (19, 38, and 112 kg ha -1) and barley (31, 62, and 124 kg ha -1) on forage dry-matter yield (DMY) of the cover crop cut as greenfeed in the seeding year, DMY of the underseeded meadow bromegrass-alfalfa mixture in the following 1 or 2 years after establishment, and forage quality [concentration of crude protein (CP), acid detergent fiber (ADF) and neutral detergent fiber (NDF)]. In the first establishment year, the no cover crop treatment produced considerably less DMY than the treatments with cover crops. Oat seeded at 112 kg ha -1 produced greater DMY than when it was seeded at 19 or 38 kg ha -1 in all four site-years, but DMY differences between the 19 or 38 kg ha -1 seeding rates were not significant in any site-year. For barley, there was no significant difference in DMY among the three seeding rates in 2000, 2001, and 2002. In 2003, barley seeded at 62 or 124 kg ha -1 produced greater DMY than when it was seeded at 31 kg ha -1, but DMYs were not significantly different between the 62 and 124 kg ha -1 seeding rates. The use of a cover crop did reduce DMY in 2003 of bromegrass-alfalfa mixture underseeded in 2002, but the type of cover crop and its seeding rate did not appear to affect DMY in any site-year. Forage quality in the seeding year was consistently superior in no cover crop treatment compared to that in treatments with cover crops, especially related to CP concentration. There was no consistent trend of forage quality in the cover crop treatments, indicating cover crops and their seeding rates had little effect on forage quality. In conclusion, oat appeared to be more sensitive to seeding rate than barley for forage DMY in the establishment year, but in the subsequent 1 or 2 years after establishment there was little effect of cover crop type and its seeding rate on DMY of bromegrass-alfalfa mixture, although DMY was considerably greater in the no cover treatment than that in treatments with cover crops in 1 site-year.
  • Authors:
    • Shabalina, E. V.
    • Korobitsyn, S. L.
    • Platunov, A. A.
  • Source: Kormoproizvodstvo
  • Issue: 1
  • Year: 2011
  • Summary: Productivity and fodder value of perennial legume and legume-grass mixtures under cover of vetch-oat mixture were studied in 2009-2010 in Kirov Region, Russia. Cover mixture consisted of spring vetch cv. Orlovskaya 4 and oat cv. Ulov with sowing rate of 0.12 and 0.06 t/ha, respectively. Red clover cv. Kirovskii 159, birds-foot trefoil cv. Solnyshko and cooksfoot cv. Khlynovskaya were used as undercrop mixture in following combinations: (1) red clover, (2) red clover + birds-foot trefoil, (3) birds-foot trefoil, (4) red clover + cooksfoot, (5) red clover + birds-foot trefoil + cooksfoot. Data on dry mass yield and number of fodder units per kg of dry mass for cover mixture and unvercover crops, as well as crude protein and cellulose content for unvercover crops are summarized in 2 tables. Productivity of cover mixture and unvercover crops varied from 3.81 to 4.18 t/ha, and from 3.86 and to 4.80 t/ha respectively with no significant difference between variants. The highest crude protein content of 17.2% was achieved in variant (3), but again with no significant difference between variants. Authors concluded that further work will be needed to achieve the high and balanced yield of cover and unvercover crops.
  • Authors:
    • Olesen, J.
    • Bindi, M.
  • Source: Regional Environmental Change
  • Volume: 11
  • Issue: Supplement 1
  • Year: 2011
  • Summary: Human activities are projected to lead to substantial increases in temperature that will impact northern Europe during winter and southern Europe during summer. Moreover, it is expected that these changes will cause increasing water shortages along the Mediterranean and in the south-west Balkans and in the south of European Russia. The consequences on the European agricultural ecosystems are likely to vary widely depending on the cropping system being investigated (i.e. cereals vs. forage crops vs. perennial horticulture), the region and the likely climate changes. In northern Europe, increases in yield and expansion of climatically suitable areas are expected to dominate, whereas disadvantages from increases in water shortage and extreme weather events (heat, drought, storms) will dominate in southern Europe. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification and abandonment in the Mediterranean and south-eastern parts of Europe. Among the adaptation options (i.e. autonomous or planned adaptation strategies) that may be explored to minimize the negative impacts of climate changes and to take advantage of positive impacts, changes in crop species, cultivar, sowing date, fertilization, irrigation, drainage, land allocation and farming system seem to be the most appropriate. In adopting these options, however, it is necessary to consider the multifunctional role of agriculture and to strike a variable balance between economic, environmental and economic functions in different European regions.
  • Authors:
    • Kugbei, S.
  • Source: Journal of Crop Improvement
  • Volume: 25
  • Issue: 3
  • Year: 2011
  • Summary: Production figures in 2008 showed that new private seed enterprises in Afghanistan produced and sold about 12,000 tons of certified wheat seed, which accounted for 95% of the total certified seed produced in the country. At a retail price of about US$1,200 per ton, the enterprises earned an average margin of 20%. When interviewed, the farmers ranked high yield as by far the most important characteristic they sought in improved varieties. Besides yield, the next important attributes were earliness, disease resistance, grain color, and bread making quality. Estimates of on-farm productivity showed that use of improved wheat varieties alone could contribute up to 33% incremental yield under irrigated conditions, whereas the use of quality seed could enhance yield further by 28%. These estimates were obtained under recommended fertilizer rates, in the absence of which yield levels would have declined substantially. Apart from wheat, other major crops the farmers grew varied by regions but in broad terms included rice, vegetables, maize, potato, cotton, barley, watermelon, and alfalfa.
  • Authors:
    • Eckard, R. J.
    • Cullen, B. R.
  • Source: Animal Feed Science and Technology
  • Volume: 166-167
  • Year: 2011