• Authors:
    • Risede, J.-M.
    • Foster, J.
    • Rhodes, R.
    • Berry, S. D.
    • van Antwerpen, R.
  • Source: International Journal of Pest Management
  • Volume: 57
  • Issue: 4
  • Year: 2011
  • Summary: Plant-parasitic nematodes cause significant yield losses to sugarcane crops in South Africa. The currently available chemicals for nematode control are both expensive and potentially detrimental to the environment. Various alternative crops have been reported to reduce the numbers of plant-parasitic nematodes. Mindful of this, we evaluated 27 cover crops in pot trials to assess their host status to important plant-parasitic nematodes of sugarcane. All of the crops tested in pots hosted significantly lower numbers of Pratylenchus than did sugarcane. Crops such as cowpeas, tomato and grazing vetch were good hosts for Meloidogyne and would not be good choices as part of a sugarcane rotation system in heavily-infested soils. Conversely, crops such as oats, wheat, forage peanuts and marigolds reduced numbers of Meloidogyne. Velvet beans increased the abundance of Helicotylenchus, a beneficial nematode genus. A field trial was also conducted to study the effect of different cover cropping sequences. Our results show that changes in nematode communities occurred within three months of growing these crops and often remained low for the duration (the remaining 15 months) of the crops' growth. Nematodes such as Pratylenchus and Tylenchorhynchus were significantly lowered and remained so for the duration of the trial.
  • Authors:
    • Joshi, O. P.
    • Billore, S. D.
    • Bhatia, V. S.
    • Ramesh, A.
  • Source: Soybean Research
  • Volume: 9
  • Year: 2011
  • Summary: The work done so far on soybean-based intercropping systems in India involving crops like sorghum, maize, pigeonpea, pearl millet, cotton, sugarcane, minor millets, wheat, rice, oilseeds and plantation crops is reviewed. The compilation brings out the possibilities of rational utilization of natural resources by resorting to diversified cultivation rather than monoculture of crops. Soybean being a short duration leguminous crop with wide agro-climatic adaptability, offers a good opportunity to fit in cropping systems in different regions with added advantage of better economic returns, risk coverage and utilization of natural resources. The benefits of sustainability can be harnessed by adoption of scientifically evaluated and suggested intercropping systems.
  • Authors:
    • Kukal, S. S.
    • Christen, E. W.
    • Hira, G. S.
    • Balwinder-Singh
    • Sudhir-Yadav
    • Sharma, R. K.
    • Humphreys, E.
  • Source: Advances in Agronomy
  • Volume: 109
  • Year: 2010
  • Summary: Increasing the productivity of the rice-wheat (RW) system in north-west India is critical for the food security of India. However, yields are stagnating or declining, and the rate of groundwater use is not sustainable. Many improved technologies are under development for RW systems, with multiple objectives including increased production, improved soil fertility, greater input use efficiency, reduced environmental pollution, and higher profitability for farmers. There are large reductions in irrigation amount with many of these technologies compared with conventional practice, such as laser land leveling, alternate wetting and drying (AWD) water management in rice, delayed rice transplanting, shorter duration rice varieties, zero till wheat, raised beds, and replacing rice with other crops. However, the nature of the irrigation water savings has seldom been determined. It is often likely to be due to reduced deep drainage, with little effect on evapotranspiration (ET). Reducing deep drainage has major benefits, including reduced energy consumption to pump groundwater, nutrient loss by leaching, and groundwater pollution. The impacts of alternative technologies on deep drainage (and thus on irrigation water savings) vary greatly depending on site conditions, especially soil permeability, depth to the watertable, and water management. More than 90% of the major RW areas in north-west India are irrigated using groundwater. Here, reducing deep drainage will not "save water" nor reduce the rate of decline of the watertable. In these regions, it is critical that technologies that decrease ET and increase the amount of crop produced per amount of water lost as ET (i.e., crop water productivity, WP ET) are implemented. The best technologies for achieving this are delaying rice transplanting and short duration rice varieties. The potential for replacing rice with other crops with lower ET is less clear.
  • Authors:
    • Wang, L.
    • van Ranst, E.
    • Li, C.
    • Tang, H.
    • Li, H.
    • Qiu, J.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 135
  • Issue: 1-2
  • Year: 2010
  • Summary: Agricultural production plays an important role in affecting atmospheric greenhouse gas concentrations. Field measurements were conducted in Quzhou County, Hebei Province in the North China Plains to quantify carbon dioxide (CO 2) and nitrous oxide (N 2O) emissions from a winter wheat-maize rotation field, a common cropping system across the Chinese agricultural regions. The observed flux data in conjunction with the local climate, soil and management information were utilized to test a process-based model, Denitrification-Decomposition or DNDC, for its applicability for the cropping system. The validated DNDC was then used for predicting impacts of three management alternatives (i.e., no-till, increased crop residue incorporation and reduced fertilizer application rate) on CO 2 and N 2O emissions from the target field. Results from the simulations indicated that (1) CO 2 emissions were significantly affected by temperature, initial SOC, tillage method, and quantity and quality of the organic matter added in the soils; (2) increases in temperature, initial SOC, total fertilizer N input, and manure amendment substantially increased N 2O emissions; and (3) temperature, initial SOC, tillage, and quantity and quality of the organic matter added in the soil all had significant effects on global warming. Finally, five 50-year scenarios were simulated with DNDC to predict their long-term impacts on crop yield, soil C dynamics, nitrate leaching losses, and N 2O emissions. The modelled results suggested that implementation of manure amendment or crop residue incorporation instead of increased fertilizer application rates would more efficiently mitigate GHG emissions from the tested agro-ecosystem. The multi-impacts provided a sound basis for comprehensive assessments on the management alternatives.
  • Authors:
    • Tomar, S. S.
    • Yadav, A. K.
    • Singh, A.
    • Pal, G.
    • Shahi, U. P.
    • Kumar, A.
    • Singh, B.
    • Gupta, R. K.
    • Naresh, R. K.
  • Source: Progressive Agriculture
  • Volume: 10
  • Issue: 2
  • Year: 2010
  • Summary: Resource conserving technologies (RCTs) with double no-till practices represents a major shift in production techniques for attaining optimal productivity, profitability and water use in rice-wheat system in Indo-Gangetic plains. Conventional tillage and crop establishment methods such as puddled transplanting in the ricewheat ( Oryza sativa L.- Triticum aestivum L.) system in the Indo-Gangetic Plains (IGP) require a large amount of water and labor, both of which are increasingly becoming scarce and expensive. We attempted to evaluate alternatives that would require smaller amounts of these two inputs. A field experiment was conducted in the Western IGP for 2 years to evaluate various tillage and crop establishment systems for their efficiency in labor, water, and energy use and economic profitability. The soil physical properties (bulk density, mean weight diameter of aggregates and infiltration rate) improved significantly compared to puddled transplanted rice-conventional till wheat system. The wide beds and double no-till with flat layouts in rice-wheat system is under evaluation in different scenario of soil, climate, crop cultivars and seeding/crop establishment techniques (direct seeding, transplanting) and showed non consistent results. Systematic information on various aspects of narrow/wide beds is lacking. The productivity of rice with wide beds was at par compared to reduced tillage transplanted rice layouts but, the wheat productivity was reverse as it was highest under wide beds. The RW system productivity was highest with wide raised beds does differ significantly with other tillage and crop establishment techniques except with mulch crop establishment techniques. The water productivity of both rice and wheat was markedly improved with wide beds compared to other tillage and crop establishment techniques. Under research managed trials (rice on double no-till flat) with basmati rice, the profitability was maximum with ZTDSR (US $ 505 ha -1) and was least with direct seeded on narrow raised beds (US$305 ha -1). The study showed that the conventional practice of puddled transplanting could be replaced with no-tillage-based crop establishment methods to save water and labor. However, the occurrence and distribution of rainfall during the cropping season had considerable influence on the savings in irrigation water.
  • Authors:
    • Schroeder, K. L.
    • Paulitz, T. C.
    • Schillinger, W. F.
  • Source: Plant Disease
  • Volume: 94
  • Issue: 1
  • Year: 2010
  • Summary: An irrigated cropping systems experiment was conducted for 6 years in east-central Washington State to examine agronomic and economic alternatives to continuous annual winter wheat ( Triticum aestivum) with burning and plowing, and to determine how root diseases of cereals are influenced by management practices. The continuous winter wheat treatment with burning and plowing was compared with a 3-year no-till rotation of winter wheat-spring barley ( Hordeum vulgare)-winter canola ( Brassica napus) and three straw management treatments: burning, straw removal, and leaving the straw stubble standing after harvest. Take-all disease and inoculum increased from years 1 to 4 in the continuous winter wheat treatment with burning and plowing, reducing plant growth compared to the no-till treatments with crop rotations. Inoculum of Rhizoctonia solani AG-8 was significantly lower in the tilled treatment compared to the no-till treatments. Inoculum concentration of Fusarium pseudograminearum was higher than that of F. culmorum, and in one of three years, the former was higher in treatments with standing stubble and mechanical straw removal compared to burned treatments. Residue management method had no effect on Rhizoctonia inoculum, but spring barley had more crown roots and tillers and greater height with stubble burning. This 6-year study showed that irrigated winter wheat can be produced in a no-till rotation without major disease losses and demonstrated how cropping practices influence the dynamics of soilborne cereal diseases and inoculum over time.
  • Authors:
    • Topa, D.
    • Cara, M.
    • Jitareanu, G.
    • Raus, L.
  • Source: Annals of the University of Craiova - Agriculture, Montanology, Cadastre Series
  • Volume: 40
  • Issue: 1
  • Year: 2010
  • Summary: The project aims the sustainable development in Romania, soil, water and carbon conservation, and counter-balances the effects of global climate change. Research carried out aimed at developing fundamental knowledge through in-depth inquiries of soil quality indicators of Moldavian Plain, regarding integrated management of soil and water. Research carried out also aimed to quantify the influence of agricultural technologies on physic, hydric, thermic, nutrient and biological soil regime, and ecological impact of these changes on ecological, energetically, hydrological, biogeochemical and breathing soil function, in specific areas of Moldavian Plain. The experiment was conducted at the Didactic Station of the "Ion Ionescu de la Brad" University of Agricultural Sciences and Veterinary Medicine of Iasi, Ezareni Farm, during Analele Universitatii din Craiova, seria Agricultura - Montanologie - Cadastru Vol. XL/1 2010 farming years 2007-2009. The experimental site is located in the East part of Romania on a chambic chernozem, with a clay-loamy texture, 6.8 pH units, 3.7% humus content and a medium level of fertilization. The soil has high clay content (38-43%) and is difficult to till when soil moisture is close to the wilting point (12.2%). We have investigated three variants of soil tillage system - conventional tillage, minimum tillage and no-till - in the crop rotation made of wheat and raps. This paper presents the results obtained in winter wheat growing as concerns the influence of the tillage method on some soil physical characteristics. Tillage system modify, at least temporarily, some of the physical properties of soil, such as soil bulk density, penetration resistance, soil porosity and soil structural stability. All the tillage operation was significantly different in heir effects on soil properties. The results indicate that soil tillage systems must be adjusted to plant requirements for crop rotation and to the pedoclimatic conditions of the area.
  • Authors:
    • Leroux, X.
    • Attard, E.
    • Lemaire, G.
    • Laurent, F.
    • Chabbi, A.
    • Nicolardot, B.
    • Poly, F.
    • Recous, S.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world, Brisbane, Australia
  • Year: 2010
  • Summary: The COSMOS-Flux project aimed at studying two situations that have important environmental impacts at a larger scale : the conversion tillage no tillage where different tillage systems have been applied for 14 years at the start of experiment; the conversion grassland annual crop where the introduction of temporary grassland into rotations is studied. The characterization of upper layers of soil for C and N pools, mineralization, immobilization and nitrification of N, along with characteristics of the nitrifying and denitrifying bacterial communities (activity, size and structure) were followed during 18 to 36 months after conversion. We observed that the tillage of soils untilled for 14 years, or the ploughing of the 5-year old grassland were major disturbances for the soils, which led to a very fast evolution of soil organic matter pools, N fluxes and microbial activities towards the characteristics observed for tilled and arable situations. Conversely, the shifts from till to no-till, and the establishment of grassland on soil previously cropped with annual species did not change significantly their soil characteristics at the time scale of the study. Among soil environmental variables, soil organic carbon appeared as a key driver of the observed responses.
  • Authors:
    • Sandor, M.
    • Domuta, C.
    • Vuscan, A.
    • Domuta, C.
    • Samuel, A.
  • Source: Research Journal of Agricultural Science
  • Volume: 42
  • Issue: 3
  • Year: 2010
  • Summary: The importance of phosphatase for plant nutrition has repeatedly been pointed out. In most soils, the organically bound P-fraction is higher than the inorganic. Phosphorus uptake by plants requires mineralization of the organic P-component by phosphatases to orthophosphate. Phosphatases are inducible enzymes that are produced predominantly under conditions of low phosphorus availability. Phosphatases are excreted by plant roots and by microorganisms. Microbial phosphatases dominate in soils. The phosphomonoesterases, so-called phosphatases differ in their substrate specificity and their pH optimum. One can thus differentiate between acid and alkaline phosphatases in the soil. Phosphatase activities were determined in the 0-20-, 20-40- and 40-60-cm layers of a preluvosoil submitted to a complex tillage (no-till and conventional tillage), crop rotation (2- and 3-crop rotations) and fertilisation [mineral(NP) fertilisation and farmyard-manuring] experiment. It was found that the activities decreased in the order: acid phosphatase activity > alkaline phosphatase activity. Each activity decreased with increasing sampling depth. No-till-in comparison with conventional tillage - resulted in significantly higher soil phosphatase activities in the 0-20-cm layer and in significantly lower activities in the deeper layers. The soil under maize or wheat was more phosphatase-active in the 3- than in the 2-crop rotation. In the 2-crop rotation higher soil phosphatase activities were recorded under wheat than under maize. Farmyard-manuring of maize - in comparison with its mineral fertilisation - led to a significant increase in each activity.
  • Authors:
    • Saseendran, S. A.
    • Nielsen, D. C.
    • Ma, L. W.
    • Ahuja, L. R.
    • Vigil, M. F.
  • Source: Agronomy Journal
  • Volume: 102
  • Issue: 5
  • Year: 2010
  • Summary: Long-term crop rotation effects on crop water use and yield have been investigated in the Central Great Plains since the 1990s. System models are needed to synthesize these long-term results for making management decisions and for transferring localized data to other conditions. The objectives of this study were to calibrate a cropping systems model (RZWQM2 with the DSSAT v4.0 crop modules) for dryland wheat ( Triticum aestivum L.), corn ( Zea mays L.), and proso millet ( Panicum miliaceum L.) production in the wheat-corn-millet (WCM) rotation from 1995 to 2008, and then to evaluate the model from 1992-2008 for two additional rotations, wheat-fallow (WF) and wheat-corn-fallow (WCF) on a Weld silt loam soil under no-till conditions. Measured biomass and grain yield for the above three rotations were simulated reasonably well with root mean squared errors (RMSEs) ranging between 1147 and 2547 kg ha -1 for biomass, and between 280 and 618 kg ha -1 for grain yield. Corresponding index of agreement (d) ranged between 0.70 and 0.95 for biomass, and between 0.87 and 0.97 for grain yield. The validated model was further used to evaluate two additional crop rotations: wheat-millet-fallow (WMF) and wheat-corn-millet-fallow (WCMF) (1993-2008) without prior knowledge of the two rotations. We found that the model simulated the mean and range of yield and biomass of the three crops well. These results demonstrated that RZWQM2 can be used to synthesize long-term crop rotation data and to predict crop rotation effects on crop production under the semiarid conditions of eastern Colorado.