• Authors:
    • Garcez, F.
    • Bacchi, L.
    • Gavassoni, W.
    • Silva, F.
  • Source: Summa Phytopathologica
  • Volume: 37
  • Issue: 3
  • Year: 2011
  • Summary: The effects of crop residues and their extracts on Sclerotinia sclerotiorum are not well documented. Three experiments were conducted with crop residues and their ethanol and partition extracts. Oat, vetch, bean, pearl millet, corn and wheat were assessed under controlled conditions. Sclerotia covered with oat, vetch, bean and pearl millet residues did not germinate carpogenically. Ethanol extracts of oat and vetch residues were efficient in inhibiting carpogenic germination whereas pearl millet and wheat did not differ from control. All partitioned ethanol extracts inhibited germination. Crop residues negatively affected the number of apothecia per sclerotium.
  • Authors:
    • Alok, T.
    • Sarawgi, S.
    • Shrikant, C.
    • Singh, M.
    • Vijendra, J.
  • Source: Journal of Soils and Crops
  • Volume: 21
  • Issue: 2
  • Year: 2011
  • Summary: Field experiment was conducted on different intercropping under irrigated condition during rabi season of 2009-10 at Indira Gandhi Krishi Vishwavidyalaya, Raipur to evaluate the yield, economics and to undertake weed studies of intercropping in rabi cereal, legume, oilseeds and spices in rice based cropping system in inceptisols. Maximum wheat equivalent yield, (65.55 q ha -1) of rabi crops was recorded in onion+coriander system over all the other intercropping treatment. Wheat+fenugreek intercropping was next in order which has also recorded significantly higher WEY (36.58 q ha -1) overwheat followed by rice, the existing cropping system (30.61 q ha -1), castor+lentil (32.78 q ha -1) and wheat+lentil (28.18 q ha -1). The highest net returns (Rs.65,292 ha -1) from rabi crops were recorded with onion+coriander because of higher value of the produce. The highest B:C ratio of rabi intercrops was recorded in onion+coriander (1.98) followed by mustard+lentil (1.90) and wheat (1.89). On the other hand, the highest weed population (172.33 and 147.00 m -2) and dry matter production (7.8 and 194 g m -2) was observed in mustard+lentil at 30 and 60 DAS. The lowest weed dry production was found in onion+coriander (1.8 g m -2) at 30 DAS, and under wheat+fenugreek (82.07 g m -2) at 60 DAS. On an average, the available N, P, K and organic carbon content were increased by 6.1, 3.6, 11.8, and 4.2%, respectively over initial values in soil after the harvest of the rabi crop.
  • Authors:
    • Macak, M.
    • Smatana, J.
  • Source: Acta Fytotechnica et Zootechnica
  • Volume: 14
  • Issue: 2
  • Year: 2011
  • Summary: The research of crop rotation pattern and field homogenization was carrying out during 2000-2010 at company Agrokarpaty Plavnica Ltd in Slovakia. The average temperature of the site during growing period is 14.9degreesC and a sum of precipitation 438 mm. The fields are situated at 300-450 m above the see level. Total acreage of arable land is 380 ha. Share of medicinal plants varied from 85 ha to 145 ha during evaluated period. The main growing medicinal and spices plants are as follows: Galega officinalis L, Medicago sativa L, Hypericum perforation L, Mentha piperita L, Melissa officinalis L, Calendula officinalis L, Fagopyrum esculentum Moench, Carum carvi L., Achilea milefolium L, Agrimonia eupatoria L, Matricaria recutita L, Plantago lanceolata L, Malva mauritiana L. As a forecrop red clover ( Trifolium pratense L), winter wheat ( Triticum aestivum L), spring barley ( Hordeum sativum L.) and oat ( Avena sativa L.) have been growing. The management practices of "Agrokarpaty Plavnica" are in full compliance with the good agricultural practices (GAP). The high priority is maintenance of soil fertility and sustain of nutrients, mainly nitrogen. The green manure, cover crop, growing of legumes and compost from own productions are used. Two steps for designing have been suggested (i) Field consolidation and homogenisation of field for crop rotations area, (ii) Proposal of crop rotation pattern. The interested area is characterized by low production potential of 8 classes of soil production categories. We have proposed new cropping pattern of 14 fields with total acreage of 180.11 ha with average field 12.87 ha. Share of medicinal and spices plants is 68.27%, share of red clover 14.29% and spring cereals 17.46%. The design of propose crop rotation allows to use organic manure mainly before medicinal plants growing for leaves drug, and incorporation of cover crops for maintenance of soil fertility. Supposed crop rotation pattern complies with basic principles of crop rotation and sustainable agriculture.
  • Authors:
    • Fu, L.
    • Jia, Q.
    • Yang, L.
    • Fan, D.
    • Zhang, P.
    • Lu, C.
    • Wang, F,
  • Source: Xinjiang Agricultural Sciences
  • Volume: 48
  • Issue: 8
  • Year: 2011
  • Summary: Objective: According to the measured data of soil temperature and air temperature in early spring in Kashgar area of Xinjiang, the temperature change characteristic about apricot wheat interplanting and the only wheat monoculture during the 24 h was analyzed. Method: The paper took Saimaiti apricot of 8 years old and Xindong-20 as investigative objects, and carried out a study of phenophase, horizontal distance, soil depth and air temperatures at different levels under the intercrop and monoculture model by ZDR-41. Result: The results showed that: (1) the total changes of soil temperature present the onefold type of "S"; (2) there were differences in the sustained time of temperature extremum under the 20 cm soil layer of different modes. The topmost and lowermost of air temperature did not have sustained time, but it had sustained time of the topmost and lowermost under the different horizontal distance in the intercrop model; (3) in the stages in germination, temperature under monoculture model was higher than intercrop model at the same soil depth. The average temperature of the stages in apricot germination was monoculture > the distance of 2 m to stem of apricot > the distance of 1 m to stem of apricot > air temperature. Conclusion: In the stages in germination of early spring, apricot orchard inter-crop wheat have definite effect to reduce soil temperature. The time change and the soil temperature were gradually ascended. In the period of apricot bloom, the horizontal distance at different levels did not have obvious effect on soil temperature.
  • Authors:
    • Zhang, S.
    • Jiang, Z.
    • Cai, J.
    • Zhong, C.
    • Wang, L.
  • Source: Journal of Northwest A & F University
  • Volume: 39
  • Issue: 7
  • Year: 2011
  • Summary: Objective: This paper studied the distribution patterns and morphological variations of fine roots in walnut ( Juglans regia)-wheat ( Triticum aestivum) agroforestry system to provide theoretical basis for the interspecific relationship research and management of agroforestry ecosystem. Method: With walnut, wheat monocropping ecosystem as control, samples were collected by soil coring method. WinRHIZO root analysis system was conducted to measure root morphology parameters. Moreover, differences of the fine roots spatial distribution and morphological variations between the agroforestry ecosystem and monocropping ecosystem were analyzed. Result: (1) The vertical gravity center of walnut fine root length in agroforestry ecosystem is 35.49 cm, compared with that in walnut monocropping ecosystem, which is 29.97 cm, moving down 5.52 cm. The distance between the radial gravity centers of walnut fine root length and the tree in agroforestry ecosystem is 0.91 m, which is 0.08 m closer to the tree than that (0.99 m) of walnut in monocropping ecosystem. The vertical gravity center of wheat root length in agroforestry ecosystem is 18.46 cm, compared with that in wheat monocropping ecosystem, which is 26.04 cm, moving up 7.58 cm. (2) The total mean root length density of walnuts in agroforestry ecosystem is 83.6 cm/dm 3, which is 135.6 cm/dm 3 in walnut monocropping ecosystem. The former decreases 38% than the latter. The total mean root length density of wheat in agroforestry ecosystem is 1.74 cm/cm 3, which is 1.22 cm/cm 3 in wheat monocropping ecosystem. The former increases 42% than the latter. (3) In 0-30 cm soil depth, the specific root length of walnut is 5 149.34 cm/g in agroforestry ecosystem, which is greater than 3 624.68 cm/g in walnut monocropping ecosystem. But in 30-100 cm soil depth, the specific root length of walnut is 2 626.59 cm/g in agroforestry ecosystem, which is smaller than the 3 906.9 cm/g in walnut monocropping ecosystem; In 0-50 cm soil depth, the specific root length of wheat is 10 019.5 cm/g in agroforestry ecosystem, smaller than the 11 811. 7 cm/g in wheat monocropping ecosystem. In 50-100 cm soil depth, the specific root length of wheat is 14 328.9 cm/g in agroforestry ecosystem, greater than the 13 389.6 cm/g in wheat monocropping ecosystem. Conclusion: In agroforestry ecosystem, most of the root competitions appear in 0-30 cm soil depth and radial 1.5-2.0 m to the tree. As responses to adapt to the competition and maximize access to resources in soils in agroforestry systems, the spatial distribution and morphology in fine roots might have a high plasticity during the growth of walnut and wheat.
  • 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:
    • Hallikainen, A.
    • Kostiainen, E.
    • Turtiainen, T.
  • Source: Journal of Environmental Radioactivity
  • Volume: 102
  • Issue: 5
  • Year: 2011
  • Summary: A survey was carried out on the activity concentrations of 210Pb and 210Po in cereal grains produced in Finland. The cereal species were wheat ( Triticum aestivum), rye ( Secale cereale), oats ( Avena sativa) and barley ( Hordeum vulgare), which account for 90% of the Finnish consumption of cereal products. The survey consisted of 18 flour and 13 unprocessed cereal samples and one hulled grain sample from 22 flour mills. According to the results, the mean 210Pb/ 210Po concentrations in wheat grains, wheat flour, rye flour, oat grains and barley grains were 0.29, 0.12, 0.29, 0.36 and 0.36 Bq kg -1, respectively. Combined with the consumption rates of the products, we assess that the mean effective doses from 210Pb and 210Po in cereal products for the adult male and female population are 22 and 17 Sv per year, respectively.
  • Authors:
    • Urashima, A.
    • Silva, C.
  • Source: Journal of Phytopathology
  • Volume: 159
  • Issue: 11/12
  • Year: 2011
  • Summary: Blast caused by Magnaporthe grisea ( Pyricularia grisea) is a disease that occurs in many important gramineous plants in Brazil such as rice, wheat, triticale and barley. In 2005, the presence of this disease was reported on black oat ( Avena strigosa) at different locations of Parana state. Due to little information of M. grisea that is infecting this host, this work aimed to characterize it at molecular, sexual and pathogenic level. DNA analysis showed that M. grisea from black oat formed a homogenous and genetic distinct group of its own, different from other hosts, including rice, wheat, triticale and barley. Isolate 15720 was an exception, because it was similar to wheat isolate. There was no sexual compatibility between M. grisea from oat and other tested hosts. In pathogenic terms, isolates of M. grisea from oat infected triticale, wheat, rye, millet, barley, sorghum and rice; cross-inoculation was positive with wheat, triticale, rice and barley.
  • Authors:
    • Wellings, C.
  • Source: Euphytica
  • Volume: 179
  • Issue: 1
  • Year: 2011
  • Summary: Stripe rust, caused by Puccinia striiformis, has been an important disease of wheat, barley, rye, triticale and certain graminaceous hosts for centuries. The significance of the disease on cultivated cereals has waxed and waned according to the vagaries of climate, inoculum levels and susceptible varieties. A progressive understanding of pathogen biology has revealed levels of specialisation between and within host groups, and these had varying impacts on the hosts concerned. The most economically important form is P. striiformis f. sp. tritici ( Pst), the causal pathogen of stripe (yellow) rust of wheat, which is the major focus of this paper. The recent discovery of the perfect stage of Pst on Berberis spp. will encourage further work to uncover the potential importance of the sexual stage in pathogen biology in regions where Berberis spp. occur. A review of the evolution of pathotypes within Pst over the past 50 years reveals recurrent pandemics emanating from a combination of specific virulence in the pathogen population, wide scale cultivation of genetically similar varieties, and agronomic practices that led to high yield potential. When these factors operate in concert, regional stripe rust epidemics have proven to be dramatic, extensive and serious in terms of the magnitude of losses and the economic hardships endured. A review of these epidemics suggests that little progress has been made in containing the worst effects of epidemics. The current status of stripe rust was gauged from a survey of 25 pathologists and breeders directly associated with the disease. It was evident that Pst remains a significant threat in the majority of wheat growing regions of the world with potential to inflict regular regional crop losses ranging from 0.1 to 5%, with rare events giving losses of 5-25%. Regions with current vulnerability include the USA (particularly Pacific North West), East Asia (China north-west and south-west), South Asia (India, Pakistan, Nepal), Oceania (Australia, New Zealand), East Africa (Ethiopia, Kenya), the Arabian Peninsula (Yemen) and Western Europe (east England). The resources deployed to contain the worst effects of Pst will need to find a balance between training a new generation of breeders and pathologists in host-pathogen genetics, and an investment in infrastructure in IARCs and NARs.
  • Authors:
    • Yang, W.
    • Liu, W.
    • Wan, Y.
    • Zhang, J.
    • Xiang, D.
    • Yong, T.
  • Source: Acta Prataculturae Sinica
  • Volume: 20
  • Issue: 6
  • Year: 2011
  • Summary: The aim of this paper was to study the mechanisms of interspecific nitrogen facilitation and transfer in the relay strip intercropping systems of "wheat/maize/soybean" and "wheat/maize/sweet potato". The methods of root barrier and 15N-isotope dilution were used to investigate the nitrogen transfer, nitrogen uptake and residual effect in the two relay strip intercropping systems. Comparing the no barrier with solid barrier, the results showed that in-season 15N uptake and 15N recovery efficiency of wheat increased remarkably, and 15N% abundance left in soil and total N content reduced obviously. In the "wheat/maize/soybean" system, the in-season 15N uptake and 15N recovery efficiency, 15N% abundance left in soil and total N content of maize with no barrier increased by 25.16%, 25.16%, 13.89% and 10.15%. But in the "wheat/maize/sweet potato" system, the value of above indices reduced by 15.98%, 15.99%, 17.37% and 5.19%. For soybean, the in-season 15N uptake and 15N recovery efficiency, 15N% abundance left in soil reduced, the soil total N content increased by 3.03%. For sweet potato, the in-season 15N uptake and 15N recovery efficiency increased, 15N% abundance left in soil and total N content reduced by 0.91% and 4.95%. In the "wheat/maize/soybean" system, the 15N uptake and 15N recovery efficiency of wheat and maize obtained from previous wheat, maize and soybean were higher than that of the "wheat/maize/sweet potato" system. The 15N uptake and 15N recovery efficiency of soybean obtained from previous wheat or maize were lower than that of sweet potato, but that from previous soybean was higher than that from previous sweet potato. The "wheat/maize/soybean" system was more beneficial to increase annual nitrogen uptake, nitrogen residual effect and maintaining soil fertility.