• Authors:
    • Kumari, S. G.
    • Ekzayez, A. M.
    • Ismail, I.
  • Source: Plant Disease
  • Volume: 95
  • Issue: 1
  • Year: 2011
  • Summary: A field survey covering the major cereal-production areas of Syria was conducted during May 2009. A total of 938 wheat and 971 barley samples with typical symptoms of viral infection were collected from 45 wheat and 58 barley fields. Serological tests showed that Wheat dwarf virus (WDV) was detected in 16 wheat (cv. Cham 8) and 5 barley (cv. Arabic abiad) samples collected from Al-Hasskah governorate (eastern region of Syria) and showing dwarfing, yellowing, and reduced heading. The identity of WDV was confirmed by PCR assay. Leafhopper transmission tests indicated that only Psammotettix provincialis was able to transmit Syrian barley WDW isolates from infected barley plants to healthy barley (48 plants became infected of 50 plants inoculated) and oats (45 of 50) under greenhouse conditions. WDV has been reported to infect cereals in other countries in West Asia and North Africa (Turkey, Tunisia and Morocco) and causes economic losses on wheat in many countries in Europe (e.g. Sweden). WDV has been reported to be transmitted in a persistent manner only by leafhoppers ( Psammotettix alienus) to a wide range of cereal and wild grasses. Two strains of WDV are known, one that primarily infects wheat and another that infects barley. This is thought to be the first report of WDV (both strains) infecting wheat and barley crops in Syria and the first report of P. provincialis as a WDV vector worldwide.
  • Authors:
    • Emeran, A. A.
    • Shtaya, M. J. Y.
    • Fernandez-Aparicio, M.
    • Allagui, M. B.
    • Kharrat, M.
    • Rubiales, D.
  • Source: Crop Protection
  • Volume: 30
  • Issue: 8
  • Year: 2011
  • Summary: Chocolate spot incited by Botrytis fabae is a serious faba bean disease of worldwide distribution. The increasing interest in sustainable tools for disease control, together with the lack of sufficient levels of genetic resistance triggered our interest in the use of intercropping as a tool for the management of this disease. The effect of intercropping on chocolate spot severity was studied in field experiments performed in Egypt, the Palestinian Territories, Spain and Tunisia, in which a susceptible faba bean cultivar was grown as a monocrop or with two mixed species intercrops of either barley, oat, triticale, wheat, pea or common vetch, or with three mixed species intercrops of wheat and berseem clover. Chocolate spot was significantly reduced when faba bean was intercropped with cereals, but not when intercropped with legumes. Suppressive effects can be ascribed to a combination of host biomass reduction, altered microclimate and physical barriers to spore dispersal.
  • Authors:
    • Dordas, C.
    • Vlachostergios, D.
    • Lithourgidis, A.
    • Damalas, C.
  • Source: European Journal of Agronomy
  • Volume: 34
  • Issue: 4
  • Year: 2011
  • Summary: Intercrops of pea ( Pisum arvense L.), a popular legume used in intercropping systems with winter cereals for forage and silage production, with wheat ( Triticum aestivum L.), rye ( Secale cereale L.), and triticale (* Triticosecale Wittmack) in two seeding ratios (60:40 and 80:20) were compared with monocrops of pea and cereals for two growing seasons. Growth rate, dry matter yield, and N uptake were determined in each intercropping system. Furthermore, several indices were used to evaluate the intercropping systems and analyze the competition and the interrelationships between mixture components. Growth rate of cereals was lower in the mixtures than in the monocrops. Dry matter yield was higher in triticale monocrop, followed by its two intercrops, and the pea-wheat 80:20 intercrop. Moreover, triticale monocrop, pea-triticale intercrops, and pea-wheat 80:20 intercrop showed the highest crude protein yield and N uptake. The land equivalent ratio (LER), relative crowding coefficient (K), actual yield loss (AYL), and system productivity index (SPI) values were greater for the pea-triticale mixtures and the pea-wheat and pea-rye mixtures (80:20), indicating an advantage of intercropping. In most intercrops, the values of partial K, AYL, aggressivity, and competitive ratio (CR) indicated that the cereal was more competitive than pea. The highest values of monetary advantage index (MAI) and intercropping advantage (IA) were recorded for the pea-triticale and the pea-wheat mixtures (80:20). Overall, pea-triticale and pea-wheat mixtures (80:20) were more productive and produced better forage quality than the other mixtures and thus could be adopted by the farmers as alternative options for forage production.
  • Authors:
    • Leap, J.
    • Klonsky, K. M.
    • Shennan, C.
    • Smith, R. F.
    • Muramoto, J.
    • Ruiz, M. S.
    • Gliessman, S. R.
  • Source: HortScience
  • Volume: 46
  • Issue: 8
  • Year: 2011
  • Summary: Legume/cereal mixed winter cover crops are commonly used by organic growers on the central coast of California, but they are unable to provide sufficient nitrogen (N) for a high N-demanding vegetable crop such as broccoli and supplemental fertilizer application may be necessary. The goals of this project were to evaluate the contribution of N from a mixed legume/cereal cover crop (CC) and feather meal and blood meal as organic fertilizers (OF) to an organic broccoli crop and to evaluate economic benefits of CC and OF to the subsequent organic broccoli crop. Trials were conducted at two sites (A and B) with different management histories. Cover crops were grown over the winter and incorporated into the soil in the spring and subsequently broccoli [ Brassica oleracea L. (Italica group)] was grown in 2006 at both sites and in 2007 at B only. Cover crop and no CC treatments were grown with supplemental organic fertilizers at four fertility levels (0, 84, 168, and 252 kg N/ha of OF) with four replicates. Generally broccoli head yields at A (14.9 to 26.3 Mg.ha -1) were higher than at B (0.7 to 17.4 Mg.ha -1 in 2006 and 5.5 to 17.9 Mg.ha -1 in 2007). Yield and aboveground biomass N were significantly increased by OF at rates up to 168 kg N/ha at A and to 252 kg N/ha at B and by CC in 2006 at both sites but not in 2007 at B. Although N content of the CC was similarly low at A (2006) and at B (2007), immobilization of soil mineral N occurred only at B. This suggests that the addition of a low N content CC was offset by high N mineralization from the soil at A with a long organic management history (greater than 33 years). Supplemental fertilizer applications may be necessary to achieve optimal yields, but the amount needed can be reduced by cover cropping in fields with a long history of cover crop-based organic management (A) or when cover crop N content is sufficiently high to prevent immobilization (B, 2006). Soil NO 3-N patterns suggest a pre-side dress nitrate test may also be useful for N management in organic broccoli. Use of cover crops increased net return above harvest and fertility costs when the yield reduction by N immobilization did not take place. However, the net return increase by the use of cover crops tended to diminish as the rate of OF application increased.
  • Authors:
    • Robles, A. B.
    • Garcia, P. A.
    • Altieri, M. A.
    • Ramos, M. E.
  • Source: Journal of Sustainable Agriculture
  • Volume: 35
  • Issue: 7
  • Year: 2011
  • Summary: We evaluate the forage yield and quality, species composition, and carrying capacity of oats and oat-vetch as fodder-cover crops, grown in almond orchards, under mineral or organic fertilizer and three harvesting regimes ("grazing," "hay," and "grain plus straw"). Also, we show preliminary results of almond yield. Differences in yield due to mineral and organic fertilization were only 9%. The carrying capacity was similar for all treatments. The almond yield was greater when the cover crop was removed early as "grazing." Therefore, oats and oat-vetch could be used as cover crops in almond orchards if removed early by livestock grazing.
  • Authors:
    • Demirci, M.
    • Turkseven, S.
    • Nemli, Y.
  • Source: Ege Universitesi Ziraat Fakultesi Dergisi
  • Volume: 48
  • Issue: 1
  • Year: 2011
  • Summary: This study was conducted to find out the influence of organic silicon surfectant in addition to the efficacy of some herbicides recommend in wheat. The wheat variety called "Gonen" was used for field trial that set up in Kocagol Village of Manyas District in Balkesir in 2009. Three different doses of fenexoprop-p-ethyl (60, 80 and 160 ml/da) and mesosulfuron-methyl+iodosulfuron-methyl-sodium (15, 20 and 40 ml/da) and doses of addition organic silicon surfactant (40 ml Sylgard309*/100 liter water) to these herbicides were applied post emergence. The aim of this research was to find out that the increase is provided by adding fenexoprop-p-ethyl. By trying these and other herbicides it came out that there established no increase.
  • Authors:
    • Kipsat, M.
    • Chepngeno, W.
    • Rop, W.
    • Langat, B.
    • Vincent, N.
  • Source: Journal of Development and Agricultural Economics
  • Volume: 3
  • Issue: 10
  • Year: 2011
  • Summary: Soil fertility management options to restore soil fertility depletion have been developed and these consist of inorganic and organic fertilizer applications. However, the adoption rates by smallholder farmers for these soil fertility management options are negligible. The overall aim of this study was to evaluate side-by-side economic aspects of different soil fertility improvement options, which have been tested in the region. Field experiments were carried out to evaluate soil fertility management options on potato-bean production in five districts in south-rift, Kenya (Narok, Bomet, Bureti, Kericho and Konoin). It appeared that application of organic residues is a more feasible and sustainable alternative to the recommended fertilizers. However, for long term yield improvement, fertilization with these recommended fertilizers would only be profitable if applied seasonally.
  • Authors:
    • [Anonymous]
  • Source: Soils Newsletter
  • Volume: 34
  • Issue: 1
  • Year: 2011
  • Summary: Through an IAEA technical cooperation project, the Turkish Atomic Energy Agency, in cooperation with the Nigde Potato Research Institute and the Soil and Fertilizer Research Institute, an innovative drip fertigation technology was implemented to improve water and nitrogen fertilizer use efficiency in potato production in the Nigde-Nevsehir Region. This technology reduced the amount of irrigation water needed by 50% and nitrogen fertilizer use by 40%, from 1000 to 600 kg N/ha. Drip fertigation technology increased water and nitrogen use efficiency by applying water and nitrogen directly to the immediate vicinity of the plant roots through a network of pipes and water emitters. Considering the magnitude and importance of potato production in the arid and semiarid areas of Turkey, the 50% reduction in crop water requirements through drip fertigation has a major impact on agricultural production and water management strategies in these areas. It was calculated that a transition from sprinkler irrigation to drip fertigation requires an initial investment cost of up to US $200/ha, depending on the sophistication of the drip fertigation system. This investment can be balanced against projected savings in time, energy, fertilizer and labour costs amounting to an estimated US $2000/ha/year. As a consequence, interest in drip fertigation has been remarkable among potato farmers in the region, so that in only three years the area under drip fertigation has increased from humble beginnings of 500 ha in 2005 to 4000 ha in 2007 and to nearly 7000 ha in 2010.
  • Authors:
    • Benismailc, M.
    • El-Otmanic, M.
    • Fadlc, A.
    • Hammoutib, B.
    • Salghia, R.
    • Abouatallaha, A.
    • Eljaouharic, N.
    • Kabousc, E.
    • Zianic, A.
  • Source: Der Pharma Chemica
  • Volume: 3
  • Issue: 6
  • Year: 2011
  • Summary: Capacitance probes were tested in a young citrus orchard for irrigation water saving; Cumulative water received by the plot reached 334 mm and 398 mm for the first and second year period respectively (irrigation+useful rain). Irrigations were made in 521 interventions when the lowest dose of 1.05 mm was used and in 210 interventions when the highest dose of 2.6 mm was applied. Capacitance probes were giving values statistically different compared to the gravimetric method, but with, however, a meaningful interrelationship; A good correlation was then obtained between real values and reading from capacitance probes, a value of 16% showed by the C-probe is equivalent to 22%. The parameters of growth, trunk diameter microvariations probes (LVDT) and components of yield are well correlated with Soil moisture and Vapor Pressure Deficit (VPD). Treatment 1 (T1) was better in cold period (December, January and February), while Treatment 4 (T4) was more efficient from flowering (March) and developed deep roots (more than 50 cm). Leaf water potential and LVDT showed the sensitivity of T1 towards climate changes during high evaporative demand days. Analysis of soil moisture data showed that the field capacity was maintained at not more than 30 cm soil depth for T1, which developed very superficial roots (45% at only 10 cm). The number of roots was significantly different between treatments, T4 was distinguished by a greater concentration of roots (8843), compared to T1 (4104). After 27 months from plantation, the Yield showed a performance of 46 T/ha recorded for the dose of 2.1 mm, when the fruit size was 70% of Size 1-3; water saving was about 50% and valuated at 105 l/kg produced.
  • Authors:
    • Tanigawa, T.
    • Yamamoto, T.
    • Al-Busaidi, A.
    • Rahman, H.
  • Source: Irrigation and Drainage
  • Volume: 60
  • Issue: 4
  • Year: 2011
  • Summary: Water stress is the primary environmental factor that limits cereal production in Mediterranean environments, where barley ( Hordeum vulgare L.) is one of the main crops. This investigation aimed at evaluating the effects of zeolite on barley growth under subsurface drip irrigation, subjected to water and heat stress. A sand dune soil was amended with Ca-type zeolite and irrigated every 2nd, 3rd, 4th and 5th day. The results showed that zeolite application significantly increased water-holding capacity of the soil and improved plant growth. Using subsurface irrigation with zeolite amendment helped to reduce water evaporation, kept more water in lower horizons, encouraged salt leaching, and the plants used water more efficiently. Plant growth parameters showed significant differences among treatments and were negatively affected by heat and water stress conditions. High temperatures caused accelerated evapotranspiration, water stress in plants and faster depletion of water from the root zone, causing substantial water loss and inducing water deficit conditions in plants. Using subsurface irrigation poses a better option for the reduction of evaporation and achieving higher water use efficiency. Application of zeolite together with subsurface irrigation may provide favorable conditions for crop production in water-scarce areas under warm environments.