• Authors:
    • Sharaiha, R.
    • Molla, A.
  • Source: Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara "Ion Ionescu de la Brad" Iasi, Seria Agronomie
  • Volume: 52
  • Issue: 1
  • Year: 2009
  • Summary: Mixed intercropping of barley and wheat has been reported as the practice of smallholder farmers in some dryland areas of Ethiopia. However, this cropping system has not yet received the attention of research. Therefore, this study was conducted to determine the level of competition and yield advantage in barley and wheat mixed intercropping under different stress levels of moisture deficit. One pot and one field experiments were conducted to address these objectives. In the pot experiment, three irrigation water levels (75-80, 50-55, and 25-30% depletion of soil available water), five intercropping ratios (%) of barley to wheat in a replacement series (100/0, 75/25, 50/50, 25/75, and 0/100), and four planting densities (4, 8, 12 and 16 plants/pot) were studied in a split-split plot design and had three sets so as to harvest at tillering, heading and maturity stages. In the field, the five intercropping ratios and the four water levels supplied by sprinkler irrigation system were studied in a split-plot design. Intra- and inter-specific competition decreased with decreasing stress levels of moisture deficit; but increased with increasing planting densities in all harvesting stages in the pot experiment. However, both competition types were higher at tillering stage but progressively decreased in later harvesting stages. Intraspecific competition was more important for barley at early stages and for wheat at later stages of the growing period. Both pot and field experiments proved that barley was less competitive than wheat towards the reproductive stage. Yield advantage of mixed intercropping of barley and wheat increased with increasing stress levels of moisture deficit under study. Yield advantage and productivity tended to be dominated by the higher yielding crop species in the mixture. This result suggests mixed intercropping of barley and wheat is not a priority in areas where moisture is not limiting in amount and distribution. It is advisable to use 50% barley+50% wheat ratio since it is difficult to predict which crop performs better than the other in such unpredictable rainfall conditions of the drylands.
  • Authors:
    • Zaragoza, C.
    • Aibar, J.
    • Cavero, J.
    • Pardo, G.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 84
  • Issue: 3
  • Year: 2009
  • Summary: Under semiarid conditions the response of crops to synthetic fertilizers is often reduced. Organic fertilizers can be used to provide a continuous source of nutrients for the crops. The soil nitrogen and crop yield in a rotation of durum wheat ( Triticum durum)-fallow-barley ( Hordeum vulgare)-vetch ( Vicia sativa) were studied during 4 years when synthetic fertilizer (chemical), compost (organic) or no fertilizer (control) were applied in a field with high initial contents of soil NO 3-N (>400 kg N ha -1), phosphorus (22 mg kg -1) and potassium (>300 mg kg -1). Changes in soil organic matter, phosphorus and potassium were also measured. During the crop period, chemical fertilization significantly increased the content of soil NO 3-N in the first 0.30 m of soil with respect to organic fertilization and the control. The yield of wheat and barley was not increased after applying chemical or organic fertilizer with respect to the unfertilized plots. The estimated losses of nitrogen were similar for the three types of fertilization, as well as the uptake of nitrogen for the total biomass produced. The initial levels of organic matter and phosphorus were maintained, even in the plots that were not fertilized, while the potassium decreased slightly. Thus, the rotation and burying of crop residues were enough to maintain the crop yield and the initial content of nutrients.
  • Authors:
    • Rhinhart, K.
    • Ong, C.
    • Ohm, J.
    • Flowers, M.
    • Corey, A.
    • Petrie, S.
    • Hayes, P.
    • Rey, J.
    • Ross, A.
  • Source: Crop Science
  • Volume: 49
  • Issue: 1
  • Year: 2009
  • Summary: Grain beta-glucan content is the most important attribute for barley ( Hordeum vulgare L.) varieties destined for the human food market. This trait is important because of the blood glucose and cholesterol-reducing properties of beta-glucans. High levels of grain protein content, test weight, and seed size and endosperm color may also add value. Seed yield potential, in part, determines the economic feasibility of producing human food varieties. To determine the potential of food barley production in the dryland production areas of the Pacific Northwest of the United States, 33 cultivars and advanced lines reported to vary in beta-glucan content were grown in 2006 and 2007 at two locations in northeastern Oregon under dryland cropping conditions. Seed yield, test weight, percentage of plump kernels, grain beta-glucan, and grain protein were measured on replicated samples from the four environments, allowing for assessment of average performance as well as genotype * environment interaction. Estimates of variance components showed that ~66% of the variability in beta-glucan content was attributable to genotype. Cultivars and lines with waxy starch had an average beta-glucan value of 55 g kg -1 compared with 35 g kg -1 for cultivars and lines with nonwaxy starch. We found significant two- and three-way interactions, but these accounted for much less of the total variation in the measured phenotypes than the main effects of variety, year, and location. Hulless accessions produced an average of 3580 kg grain ha -1 compared with 4260 kg grain ha -1 for the hulled accessions. Hulled, waxy-starch varieties appear to have the greatest agronomic potential for dryland production, as they combine high yield potential and grain beta-glucan percentage.
  • Authors:
    • Thomas, R.
    • Aw-Hassan, A.
    • Turkelboom, F.
    • Bruggeman, A.
    • Rovere, R.
    • Al-Ahmad, K.
  • Source: Journal of Environment & Development
  • Volume: 18
  • Issue: 2
  • Year: 2009
  • Summary: This article reviews work that had the objective of introducing agricultural technologies in a marginal dryland area, the Khanasser Valley, northwestern Syria. The highly variable rainfall is barely sufficient to support livelihoods in this traditional barley-livestock production system. The valley is representative of other marginal dryland areas in West Asia and North Africa. We used a farmer-participatory approach to evaluate the performance of agricultural technologies for dry marginal areas in terms of their contribution to livelihoods and effect on the environment. The integrated approach allowed comprehensively comparing and evaluating the viability of promising technologies, including novel crops, intercropping, soil management techniques, and livestock rearing. The results show that improved barley varieties, olives, cumin, and lamb fattening can improve livelihoods, particularly for the land-owning households, whereas other households can benefit indirectly in terms of employment spillovers. These options are also environmentally friendly and sustain the natural resource base.
  • Authors:
    • Murari, S.
    • Pala, M.
    • Masri, S.
    • Ryan, J.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 40
  • Issue: 1/6
  • Year: 2009
  • Summary: Mediterranean agriculture is mainly rainfed, with drought being the main crop production constraint, and is based on cereals, wheat ( Triticum spp), and barley ( Hordeum vulgare). Fallow was a traditional practice to conserve soil moisture, but because of land-use pressure it is giving way to cereal monoculture, which is unsustainable. The substudy reported here was part of a long-term rotation trial that sought to examine alternative crop rotation options, that is, durum wheat ( T. durum var durum) in rotation with fallow, summercrop (melon, Citrullus vulgaris), wheat (continuous cropping), chickpea ( Cicer arietinum), lentil ( Lens culinaris), vetch ( Vicia sativa), and medic ( Medicago spp). Ancillary treatments involved nitrogen (N) applied to the cereal phase and variable stubble grazing intensity (stubble retention, medium grazing, and heavy grazing or complete stubble removal). This substudy, conducted in the final 3 years of the 14-year trial, involved sampling soil and plants within the cropped rotation plots and sampling soil within bare microplots in selected larger rotation plots. We measured N forms in soil samples at different depths and throughout the seasons. Despite variation within and between seasons, the rotation effect of enhanced N was significant and consistent, being highest for vetch and medic, intermediate for chickpea and lentil, and least for continuous cereal, summer crop, and fallow. Therefore, legume-based cereal rotations can enhance soil N and thus save on N fertilizer. In bare microplots, total N decreased, labile N was inconsistent, mineral N increased, and biomass N increased and remained stable during the cropping season and then sharply declined. The nutrient dynamic data complemented the crop yield, water-use efficiency, and soil aggregation data from the trial to support the argument for using legumes in cereal rotations in place of fallow and continuous cereal cropping.
  • Authors:
    • Jabro, J.
    • Caesar-TonThat, T.
    • Sainju, U.
  • Source: Soil Science Society of America Journal
  • Volume: 73
  • Issue: 5
  • Year: 2009
  • Summary: Tillage and cropping sequence may influence C and N sequestration, microbial activities, and N mineralization in dryland soil aggregates. We evaluated the 21-yr effect of tillage and cropping sequence combinations on C and N fractions in aggregates of a Dooley sandy loam (fine-loamy, mixed, superactive, frigid Typic Argiustolls) at the 0- to 20-cm depth in eastern Montana. Tillage and cropping sequences were no-tilled continuous spring wheat (NTCW) ( Triticum aestivum L.), spring-tilled continuous spring wheat (STCW), fall- and spring-tilled continuous spring wheat (FSTCW), fall- and spring-tilled spring wheat-barley ( Hordeum vulgare L.) (1984-1999) followed by spring wheat-pea ( Pisum sativum L.)(2000-2004)(FSTW-B/P), and spring-tilled spring wheat-fallow (STW-F). Carbon and N fractions were soil organic C (SOC), total N (STN), particulate organic C and N (POC and PON), microbial biomass C and N (MBC and MBN), potential C and N mineralization (PCM and PNM), NH 4-N, and NO 3-N. Aggregate proportion was greater in NTCW than in FSTCW in the 4.75- to 2.00-mm aggregate-size class at 0 to 5 cm but was greater in STW-F than in STCW in the 2.00- to 0.25-mm size class at 5 to 20 cm. After 21 yr, STW-F reduced SOC, STN, POC, and PON concentrations in aggregates by 34 to 42% at 0- to 5-cm and by 20 to 32% at 5- to 20-cm compared with NTCW and STCW. The PCM and MBC were greater in NTCW and STCW than in STW-F in the
  • Authors:
    • Caesar-TonThat, T.
    • Lenssen, A.
    • Sainju, U.
    • Evans, R.
  • Source: Agronomy Journal
  • Volume: 101
  • Issue: 2
  • Year: 2009
  • Summary: Novel management practices are needed to improve the declining dryland crop yields and soil organic matter contents using conventional farming practices in the northern Great Plains. We evaluated the 21-yr effect of tillage and cropping sequence on dryland grain and biomass (stems+leaves) yields of spring wheat ( Triticum aestivum L.), barley ( Hordeum vulgare L.), and pea ( Pisum sativum L.) and soil organic matter at the 0- to 20-cm depth in eastern Montana, USA. Treatments were no-tilled continuous spring wheat (NTCW), spring-tilled continuous spring wheat (STCW), fall- and spring-tilled continuous spring wheat (FSTCW), fall- and spring-tilled spring wheat-barley (1984-1999) followed by spring wheat-pea (2000-2004) (FSTW-B/P), and the conventional spring-tilled spring wheat-fallow (STW-F). Spring wheat grain and biomass yields increased with crop growing season precipitation (GSP) and were greater in STW-F than in FSTCW and FSTW-B/P when GSP was
  • Authors:
    • Singh, K.
    • Nandita, G.
    • Alka, S.
    • Ritu, M.
    • Sonu, S.
  • Source: Soil Science Society of America Journal
  • Volume: 73
  • Issue: 5
  • Year: 2009
  • Summary: The application of organic amendments in agroecosystems has been widely recommended, but the impact of their C/N ratio on the stabilization and sequestration of soil organic carbon (SOC) is often unaccounted for. The influence of the C/N ratio of amendments on soil physicochemical properties in a rice ( Oryza sativa var. NDR97)-barley ( Hordeum vulgare var. Lakhan) rotation tropical dryland agroecosystem was compared with an undisturbed grassland. Chemical fertilizer in the form of urea and three organic inputs ( Sesbania aculeata shoot, low C/N ratio; air-dried straw of wheat ( Triticum aestivum var. Malviya 533), high C/N ratio; and S. aculeata shoot+wheat straw, high and low C/N ratio combined) carrying an equivalent amount of N, were added to plots of the agroecosystem once during each annual cycle. Soil water-holding capacity (WHC), porosity, SOC, total N, and aggregate stability were improved in the wheat straw and S. aculeata shoot+wheat straw treatments, reaching levels comparable with the grassland. Soil WHC, porosity, and SOC influenced the productivity of the grassland and the agroecosystem. The grassland recorded highest SOC (53% higher relative to control) followed by the wheat straw (+47%), S. aculeata shoot+wheat straw (+37%) and soil total N was greatest in the S. aculeata shoot+wheat straw treatment (+37.5%). Aggregate stability and macroaggregate distribution were also higher in the wheat straw and S. aculeata shoot+wheat straw treatments, however, the microaggregate and silt+clay fractions showed a reverse trend. Management practices with a higher residue-C return in the agroecosystem resulted in increased aggregate stability and aggregate-associated SOC, with C storage attaining levels similar to the natural system.
  • Authors:
    • Gajbhiye, K. S.
    • Ray, S. K.
    • Prasad, J.
    • Singh, S. R.
  • Source: Agropedology
  • Volume: 19
  • Issue: 2
  • Year: 2009
  • Summary: Detailed soil survey of Selsura KVK research farm of Dr. P.D.K.V., Akola in Wardha district, Maharashtra was carried out using 1:6000 scale cadastral map. There were nine soil series and thirteen mapping units. The soils were very dark gray to very dark grayish brown in hue 10YR, calcareous and clayey but differed in depth and are classified under Entisols, Inceptisols and Vertisols. In general, pH (8.0-9.2) increased with depth whereas reverse trend was observed for organic carbon. Soils of Selsura-1 are prone to sodicity problems. DTPA-Zn and Fe were deficient in these soils but DPTA-Mn and Cu were optimum. The mapping units were grouped under II to IV land capability classes and 2 to 4 land irrigability classes. Except soils of Selsura-7 series (very shallow), others are moderately or marginally suitable for one or more commonly growing rainfed kharif crops viz. cotton, sorghum, pigeonpea, soybean and groundnut.
  • Authors:
    • Ray, J.
    • Smith, R.
    • Castlebury, L.
    • Mengistu, A.
    • Bellaloui, N.
  • Source: Plant Disease
  • Volume: 93
  • Issue: 10
  • Year: 2009
  • Summary: Phomopsis longicolla is a major seed pathogen of soybean ( Glycine max) in hot, humid environments. The objective of this study was to monitor the infection and development of P. longicolla on vegetative and reproductive tissues of six cultivars and to determine the relationship between this infection and subsequent seed infection and seed germination. Cultivars were grown for 3 years (2002 to 2004) without irrigation or with irrigation applied at pre- plus postflowering or at postflowering growth stages. P. longicolla was isolated most frequently from leaf, stem, pod, root, and seed. Diaporthe phaseolorum and three unidentified Phomopsis sp. were also isolated. Diaporthe aspalathi, which previously has not been reported on soybean, was also recovered from leaf samples. These isolates, however, were recovered very infrequently. Recovery of P. longicolla from roots was much lower than from leaves, stems, and pods in all years and irrigation environments. The recovery of P. longicolla from seed was affected by irrigation environments. Seed from irrigated plots had more P. longicolla than that from nonirrigated plots. Isolation of P. longicolla from seed was negatively correlated with percentage of seed germination in irrigated environments but not in the nonirrigated environment. Pod infection was correlated with seed infection in all three irrigation environments. Even though infection of leaves and stems increased with increasing moisture availability, such infection did not consistently correlate with seed infection. Seed germination and seed infection were negatively correlated with percent hard seed. This study provided the first demonstration of the seasonal progression of P. longicolla on soybean cultivars grown under three irrigation environments.