• Authors:
    • Jauhiainen, L.
    • Peltonen-Sainio, P.
    • Hakala, K.
  • Source: The Journal of Agricultural Science
  • Volume: 149
  • Year: 2011
  • Summary: Global warming has accelerated in recent decades and the years 1995-2006 were the warmest ever recorded. Also, in Finland, the last decade has been exceptionally warm. Hence, this study examines how current field crop cultivars, adapted to northern long-day conditions and short growing seasons, have responded to the elevated temperatures, especially with regard to determination of yield potential and quality. These comparisons were carried out with spring and winter wheat (Triticum aestivum L.), oats (Avena sativa L.), barley (Hordeum vulgare L.), winter rye (Secale cereale L.), pea (Pisum sativum L.) and rapeseed (turnip rape, Brassica rapa L. and oilseed rape, B. napus L.). Long-term data sets of MTT Official Variety Trials and the Finnish Meteorological Institute were used to study crop responses to precipitation and elevated temperatures at different growth phases. The MTT data sets were also grouped into experiments that could be considered typical of the temperature conditions in the period 1971-2000 seasons (termed '1985' conditions) or typical of the period 2010-39 (termed '2025'). At elevated temperatures, yields generally declined in these relatively cool growing conditions of northern Europe, except for pea. Elevated temperatures tended to have negative effects both in the pre- and post-anthesis phases, but the response depended on species. The response was probably associated with reduced water availability, which limited yield determination, especially in early growth phases. For example, in spring cereals a decrease in early summer precipitation by 10 mm decreased yields by 45-75 kg/ha. As warmer conditions also typically hastened development and growth in such generally cool growing conditions of Finland, it is essential that breeding programmes produce cultivars that are less sensitive to elevated temperatures, which are likely to become more frequent in future.
  • Authors:
    • Jauhiainen, L.
    • Peltonen-Sainio, P.
    • Sadras, V. O.
  • Source: Field Crops Research
  • Volume: 124
  • Issue: 2
  • Year: 2011
  • Summary: In the northernmost European environments of Finland, large variability in the yield and quality of crops is a critical source of uncertainty for growers and end-users of grain. The aims of this study were (i) to quantify and compare the plasticity, i.e., cultivar responsiveness to environment, in yield of spring oat, spring wheat, six-row barley, two-row barley, winter rye, winter wheat, turnip rape and oilseed rape, (ii) to explore the existence of hierarchies or positive correlations in the plasticity of agronomic, yield and quality traits and (iii) to probe for trends in yield plasticity associated with different eras of breeding for yield potential and agronomic traits. Plasticities of yield, agronomic and quality traits were derived as slopes of norms of reaction using MTT Agrifood Research Finland data sets combining long-term (1970-2008 for cereals and 1976-2008 for rapeseed) results from 15 to 26 locations. Plasticity of yield ranged typically between 0.8 and 1.2, was smallest for six-row barley (0.84-1.11) and largest for winter rye (0.72-1.36). We found two types of associations between plasticity of yield and yield under stressful or favourable conditions for cereals but none for rape. In spring wheat, oat and six-row barley, high yield plasticity was associated with crop responsiveness to favourable conditions rather than yield reductions under stressful conditions. Modern spring wheat cultivars had higher maximum grain yields compared to older ones at the same level of plasticity. In winter wheat and rye, high yield plasticity resulted from the combination of high yield in favourable conditions and low yield in stressful environments. Many associations between yield plasticity and other traits were identified in cereals: e.g., high yield plasticity was often associated with higher grain weight, more grains per square meter, later maturity (contrary to turnip rape), shorter plants, less lodging and lower grain protein content and in winter cereals with higher winter damage. (C) 2011 Elsevier B.V. All rights reserved.
  • Authors:
    • Isla, R.
    • Salmeron, M.
    • Cavero, J.
  • Source: Field Crops Research
  • Volume: 123
  • Issue: 2
  • Year: 2011
  • Summary: Under semiarid Mediterranean conditions irrigated maize has been associated to diffuse nitrate pollution of surface and groundwater. Cover crops grown during winter combined with reduced N fertilization to maize could reduce N leaching risks while maintaining maize productivity. A field experiment was conducted testing two different cover crop planting methods (direct seeding versus seeding after conventional tillage operations) and four different cover crops species (barley, oilseed rape, winter rape, and common vetch), and a control (bare soil). The experiment started in November 2006 after a maize crop fertilized with 300 kg N ha(-1) and included two complete cover crop-maize rotations. Maize was fertilized with 300 kg N ha(-1) at the control treatment, and this amount was reduced to 250 kg N ha(-1) in maize after a cover crop. Direct seeding of the cover crops allowed earlier planting dates than seeding after conventional tillage, producing greater cover crop biomass and N uptake of all species in the first year. In the following year, direct seeding did not increase cover crop biomass due to a poorer plant establishment. Barley produced more biomass than the other species but its N concentration was much lower than in the other cover crops, resulting in higher C:N ratio (> 26). Cover crops reduced the N leaching risks as soil N content in spring and at maize harvest was reduced compared to the control treatment. Maize yield was reduced by 4 Mg ha(-1) after barley in 2007 and by 1 Mg ha(-1) after barley and oilseed rape in 2008. The maize yield reduction was due to an N deficiency caused by insufficient N mineralization from the cover crops due to a high C:N ratio (barley) or low biomass N content (oilseed rape) and/or lack of synchronization with maize N uptake. Indirect chlorophyll measurements in maize leaves were useful to detect N deficiency in maize after cover crops. The use of vetch, winter rape and oilseed rape cover crops combined with a reduced N fertilization to maize was efficient for reducing N leaching risks while maintaining maize productivity. However, the reduction of maize yield after barley makes difficult its use as cover crop. (C) 2011 Elsevier B.V. All rights reserved.
  • Authors:
    • Budzynski, W.
    • Szemplinski, W.
  • Source: ACTA Scientiarum Polonorum, Agricultura
  • Volume: 10
  • Issue: 2
  • Year: 2011
  • Summary: The paper comprises a review of the results of studies on cereal mixtures published in 2003-2007 in the Polish scientific literature. There are presented herein the most important issues concerning yield ability, weed, pest and diseases infestation. Cereal mixtures occupy the highest area among spring cereals in Poland and grain harvested from mixtures plays an important role in production of feedstock in the country. The highest concentration of mixtures is noted in the eastern region and the lowest in the south-western part of Poland. The higher yield ability of mixtures compared to pure cereal stands is connected with complementary utilization of environmental resources in different time, space (under- or aboveground) or form (water, light, nutrients) by mixtures' components as well as with competition, responsible for changes in proportion of components in the mixture yield. The better stability of yield is attributed to a better competition ability against weeds and lower susceptibility of mixtures to diseases compared to pure stands. Mixed stands show a better response to some agronomical factors, such as irrigation, mineral fertilization and chemical protection against pests, weeds and diseases. A higher proportion of naked forms of barley and oat in mixtures has been recommended recently. Therefore, the mixture yields are lower than those of mixtures with hulled forms but their feeding value is higher, because of a lower content of fibre and a higher content of protein and fat.
  • Authors:
    • Calin, L.
    • Taranu, I.
    • Tabuc, C.
  • Source: Archiva Zootechnica
  • Volume: 14
  • Issue: 4
  • Year: 2011
  • Summary: Fungal mycoflora and mycotoxin contamination were determined in 86 samples (21 maize, 21 wheat, 11 barley, 4 oats, 1 rye, 12 soya, 6 sunflower, 4 colza, 3 rice, 3 triticale), coming from the south-eastern part of Romania during the 2008 to 2010 period. The most frequent fungal contaminants belonged to the Aspergillus and Fusarium genera, maize was the most contaminated cereal. The main toxinogenic species identified were A. flavus, A. fumigatus, F. graminearum, F. culmorum in all cereals Aflatoxin B1 (AFB1), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEA) and fumonisins (FUMO), contents were analyzed by ELISA. More than 90% of the samples were found to be contaminated by at least one toxin. The most frequent mycotoxin was the deoxynivalenol (71.60%). Around 40% of samples were contaminated with AFB1 and FB. Ochratoxine A and zearalenone were found in 16% and 32% of samples respectively. These results demonstrated that cereals produced in Romania present a particular pattern of fungal mycoflora and mycotoxin contamination since DON, ZEA and FUMO as well as AFB1 and OTA were observed.
  • Authors:
    • Farran, M.
    • Nimah, M.
    • Yau, S. K.
  • Source: Agricultural Water Management
  • Volume: 98
  • Issue: 12
  • Year: 2011
  • Summary: In rainfed Mediterranean areas, early sowings which lead to early growth and maturity to escape terminal heat and drought usually give higher grain yield than late sowings in years when rains come early. We test the hypothesis that early sowing coupled with a small amount of irrigation to ensure earlier emergence increases grain yield significantly, while improving irrigation water productivity. Replicated field experiments were conducted for 4 years in the semi-arid central Bekaa Valley of Lebanon. Barley was sown early, and half of the plots were irrigated with 25-30 mm of water immediately after sowing (EI). Half of the plots also received irrigation around heading stage (LI). Besides yields, other agronomic data were collected throughout crop growth, and the supplemental irrigation water use efficiency (WUE SI) was calculated. Our results confirm the hypothesis that in Mediterranean areas early sowing followed immediately with a small amount of irrigation increases barley grain yield significantly. Farmers in the region should seriously consider practicing this technique as it produces a higher WUE SI than irrigation at the heading stage.
  • Authors:
    • Leifert, C.
    • Critchley, C. N. R.
    • Eyre, M. D.
    • Wilcockson, S. J.
  • Source: European Journal of Agronomy
  • Volume: 34
  • Issue: 3
  • Year: 2011
  • Summary: A survey of 128 plots, in 2008, of a trial where the effects of crop protection can be separated from those of fertility management, generated weed cover data within six crops (winter wheat, winter barley, spring barley, potatoes, cabbages and a grass/clover ley). The effects of the 2008 crop types, of the two preceding crops and of organic and conventional crop protection and fertility management, were assessed using mixed-effects models and constrained ordination. Cover data for 22 weed species and for monocotyledon, dicotyledon, annual, perennial and total weed cover were used. Cover of 15 weed species, and of the five weed groups, was significantly affected by 2008 crops, with cover highest in spring beans and cabbage. Nine and four weed species 2008 cover were significantly related to crops grown in 2007 and 2006 respectively, as were dicotyledon, annual and total weed cover, but not monocotyledon or perennial cover. Cover of 15 species, and the five groups, was significantly higher in plots with organic crop protection, but only eight species and annuals were significantly affected by fertility management. Crop:crop protection produced the most significant interactions with most cover in organically managed plots. Five species, perennials and total weed cover produced significant three-factor models. The greatest weed cover was in organic crop protected but conventionally fertilised spring barley and the least in totally conventional winter barley. Other factors such as crop density and mechanical weeding also affected 2008 weed cover. The ordination indicated that most of the 22 species were strongly associated with crops from all three years. The sequence of crops in the rotation had a profound effect on weed cover. Where three spring-sown, difficult to weed, crops were grown in sequence (spring beans, potatoes and vegetables, spring barley) weed cover increased. However, cover was limited in grass/clover and some cereal plots with different preceding crops. Models predicting weed cover may need to take into account crop sequences within crop rotations, as well as the more usual management inputs. (C) 2011 Elsevier B.V. All rights reserved.
  • Authors:
    • Gabriel, J. L.
    • Quemada, M.
  • Source: European Journal of Agronomy
  • Volume: 34
  • Issue: 3
  • Year: 2011
  • Summary: Cover crops in dry regions have been often limited by low nutrient and water-use efficiency. This study was conducted during 3.5 years to determine the effect of replacing bare fallow by a cover crop on yield, N uptake, and fate of labeled fertiliser in an intensive maize production system. Three treatments were studied: barley ( Hordeum vulgare L.), vetch ( Vicia villosa L.) and bare fallow during the intercropping period of maize ( Zea mays L.). All treatments were irrigated and fertilised following the same procedure, and a microplot in each plot was established with 210 kg N ha -1 of double labeled ammonium nitrate. Crop yield and N uptake, soil mineral N (N min), and recovery of 15N in plant and soil were determined after maize harvest and killing the cover crop. Replacing bare fallow with cover crops did not affect subsequent maize yield but affected N uptake. Vetch increased N supply by legume residues after the second year, and the N content in grain by the third. Nitrogen recover from fertiliser was not affected by treatment and averaged 46%. Barley recovered more 15N during the autumn-winter period than vetch or fallow. Under representative conditions, average barley N content was 47, vetch 51, and spontaneous vegetation content 0.8 kg N ha -1. Recovery of 15N in barley comprised 19% of total N content in aerial biomass, while only 4% in vetch. Vetch enhanced soil 15N recovery more than other treatments, suggesting its presence in a fairly stable organic fraction unavailable for maize uptake or lost. Replacing bare fallow by a cover crop only reduced fertiliser losses in a year with abundant precipitation. Nevertheless, reduction in soil N min in vetch and bare fallow treatments was similar, showing that N losses can be reduced in this cropping system, either by replace bare fallow with barley or smaller N fertiliser application to maize.
  • Authors:
    • Gertsson, U.
    • Linden, B.
    • Gunnarsson, A.
  • Source: HortScience
  • Volume: 46
  • Issue: 5
  • Year: 2011
  • Summary: Nitrogen (N) tied up in or lost from decomposing biomass decreases the residual N effects of green manure and of other crop residues. During anaerobic degradation in a biogas digestor (biodigestion), N mineralization takes place under conditions in which losses can be kept to a minimum. Therefore, biodigestion of green manure biomass and beet foliage was tested to generate readily available N and compared with a direct green manure fertilization system. The effluent was applied as fertilizer in field experiments on a sandy soil as a tool for improving N supply for an organic farming system. Data from the field experiments were used for simulating the amount of net inorganic N equivalents (inorganic N equivalents from effluent plus inorganic N equivalents from pre-crops) in three crop sequences: A) green manure ley, red beets rye; B) harvested ley, red beets, winter rye; and C) harvested ley, spring barley, red beets in which (B) and (C) represented biogas nutrient management systems and (A) a green manure system. When all available effluent from biogas production from 1 ha of grass clover ley with two or three harvests (2H-ley or 3H-ley) and one hectare of beet foliage was used as a fertilizer for red beets (Beta vulgaris var. conditiva Alef) after barley (Hordetum vulgare L.), the yield of marketable red beets increased by 5.7 Mg.ha(-1) (33%) with effluent from 2H-ley and beet foliage and 9.1 Mg.ha(-1) (53%) with effluent from 3H-ley and beet foliage compared with red beets grown without effluent fertilization after a green manure ley. When total dry matter production was taken into account, the advantage for the BC systems with 2H- and 3H-Iey was 15% and 28%, respectively. The nitrate concentration in the red beets was not higher with effluent supplied at this level than with green manure as the only N source. The simulated amount of net inorganic N equivalents was 128 kg N for the whole of crop sequence (C) with 1 ha of each crop and where effluent supply to red beets was based on digested biomass in ley and beet tops. The corresponding amount of net inorganic N equivalents for the green manure crop sequence (A), in which no effluent was supplied, was 73 kg N. Unused soil mineral N (0- to 90-cm depth) at red beet harvest indicated that the risk of leaching in BG systems was lower than in GrM systems (88, 76, and 61 kg N(min)/ha left after unmanured beets after Gr-M-Iey, low manured beets after 3H-ley and high manured beets after barley, respectively). Effluent fertilization of red beets directly after 2H- and 3H-ley gave unexpectedly low yield responses compared with red beets after barley. The reasons may be the result of nutritional imbalance of other nutrients than N or may be plant pathological in nature. The conclusion is that a nutrient management system with biodigestion can increase net inorganic N equivalents and reduce risk for N leaching, but inappropriate use of the effluent, i.e., at an unsuitable point in the crop rotation, may negate the benefits.
  • Authors:
    • Gupta, U. S.
  • Year: 2011
  • Summary: This volume looks at the use of crops for a myriad of purposes, including the prevention and/or mitigation of various diseases, vaccine and antigen production, biofuel production, and the the suppression of weeds. It explores new emnphasis on medicinal properties of crops and examines the use of genetic engineering in crop production. The crops discussed include: rice, wheat, barley, oat, rye, maize, sorghum, potato, sweet potato, cassava, Phaseolus beans, Vigna sp., broad bean, chickpea, tomato, broccoli, cauliflower, cabbage, bitter gourd, pumpkin, spinach, onion, soyabean, groundnut, oilseed Brassica, sunflower, sugarcane, cotton, and tobacco.