• Authors:
    • Cociu, A. I.
  • Source: Romanian Agricultural Research
  • Issue: 28
  • Year: 2011
  • Summary: This research was aimed to identify the most suitable tillage systems for sustainable winter wheat ( Triticum aestivum L.) yield levels, with best economic efficiency, assuring at the same time high quality soil physical and mechanical properties. The field experiments were carried out at Fundulea on a cambic chernozem soil type. Four tillage systems were tested to determine their influence on soil water content, soil macro-aggregates, resistance to soil penetration, wheat grain yield and its components, and crop economic efficiency. The following tillage systems were studied: traditional, with moldboard plough (TS); chisel plough tillage - primary tillage executed with chisel implement type without furrow over throwing (CS); disc/sweep tillage, providing a combined effect of vegetal remnants chopped with disc implements along with soil work with arrow type tools, without furrow over throwing (DS); No till (NT) - without any tillage work. In comparison with TS variant, soil conservation tillage systems (SCTS), as CS, DS and NT, increased the soil water content, recorded at seeding time, with 0.8%, 3.9%, and 4.1%, respectively. Soil water content, recorded at harvest time for CS and NT variants was 1.3% and 2.5% higher than in the case of TS (P2 mm with 5.5%, and the mean weighted diameter of soil particles resulted by dry sieving, with 5.5% and 10%, respectively. Yield components recorded for soil conservation tillage systems (CS, DS, and NT) did not differ significantly from those evaluated for traditional system (TS), but the superior values of 1000 kernels weight and spike density suggest that these components contributed more to higher yields, obtained with SCTS, than grain weight per spike, number of grain per spike, and number of grains per square meter. With regards to economic efficiency, the outputs of all tested SCTS were significantly greater than the TS. The present study, revealing important advantages of soil conservation tillage systems over the traditional one, revealing the improvement of soil physical and mechanical properties, higher winter wheat yield levels and higher crop economic efficiency, invites farmers from South Plain of Romania to adopt soon these new progressive systems.
  • Authors:
    • Cociu, A. I.
    • Alionte, E.
  • Source: Analele Institutului National de Cercetare-Dezvoltare Agricola Fundulea
  • Volume: 79
  • Issue: 2
  • Year: 2011
  • Summary: Grain yields of winter wheat (Triticum aestivum L.), maize ( Zea mays L.), and soybean [ Glycine max. (L.) Merr], in rotation were significantly influenced by soil deep loosening and tillage system, depending on water supply (irrigation application). Scientific literature regarding the influence of these agronomic factors on the yield quality of the respective three crops, in rotation, is quite limited. For this study, a field experiment was carried out at Fundulea, which is located in the eastern part of the Danube Plain, on a cambic chernozem soil type. One of the main objectives was to determine how the grain yield quality of winter wheat, maize and soybean is influenced by different reduced tillage systems, in comparison with the traditional (conventional) one, as well as by the direct seeding in non-worked ground, or in strip till, with and without soil deep loosing, under different irrigations. Regarding the maize, the water provisioning * tillage system interaction was very significant (P0.05). Under the three water provisions applied, protein content had values between 40.0%, recorded when the normal irrigation rate was used, at no till system, and 41.5%, recorded for the dry conditions, also at no till system. The 1,000 kernel weight varied between 120 g, registered for the dry conditions at no till variant, and 159 g, registered for normal irrigation rate, also at no till system. The results of this research do not make evident a certain tendency of protein content, but show clearly that the fat content increases concomitantly with grain yield growing. As concerns the winter wheat crop, the water provisioning * tillage system interaction was not significant (P>0.05). Protein content was comprised between 13.2%, registered when the normal irrigation rate was applied at no till system variant, and 15.7%, under dry conditions, at the traditional tillage system. The minimum value of 1,000 kernel weight was 37 g, recorded for dry conditions at chisel tillage variant, and the highest value, of 47 g, was obtained when normal irrigation rate was applied to no till variant.
  • Authors:
    • Alionte,E.
    • Cociu,A. I.
  • Source: Romanian Agricultural Research
  • Issue: 28
  • Year: 2011
  • Summary: Previous research revealed that winter wheat ( Triticum aestivum L.), maize ( Zea mays L.), and soybean [ Glicine max (L.) Merill] respond more or less to the soil deep loosening work and different tillage systems, depending on the environment. The few data available showed that these agricultural practices also have a certain influence on nutritive values and physical properties of the harvested products. A three year (2008-2010) winter wheat, maize and soybean field experiment was carried out at Fundulea, Romania, on a cambic chernozem type, with the objective of evaluating the influence of different conservative tillage systems (chisel till, disc till, strip till and no till), with and without deep soil loosening, on yield and some important quality parameters. This research revealed that for winter wheat, the tillage systems and climatic conditions which favored grain yield were unfavorable for protein content. Deep soil loosening and tillage systems had a similar influence on protein and grain yields. 1000 kernels weight and test weight were not influenced significantly by the deep soil loosening and tillage systems. For maize, the application of no till resulted in a significant grain yield increase. Conservation tillage systems may influence negatively grain protein content, depending on the climatic conditions. Protein, fat and starch yields were significantly influenced by tillage systems, year and their interaction. These influences were caused mainly by the magnitude of grain yields differences. 1000 kernels weight and test weight were not significantly influenced by the deep soil loosening and tillage system. For soybean, climatic conditions and tillage systems which influenced the grain yield, affected in a similar way the protein and fat contents. Deep soil loosening had a significant influence only on the grain yield and protein content. Deep soil loosening, tillage system and climatic conditions which influenced the grain yield affected similarly the protein yield. In the case of fat yield, these effects are more or less the same only for deep soil loosening and years, but not for tillage systems.
  • Authors:
    • Poswal, R. S.
    • Yadav, A.
    • Gupta, R. K.
    • Gill, S. C.
    • Chhokar, R. S.
    • Kumar, V.
    • Sharma, R. K.
    • Kumar, A.
    • Mehta, A.
    • Kleemann, S. G. L.
    • Cummins, J. A.
    • Coventry, D. R.
  • Source: Field Crops Research
  • Volume: 123
  • Issue: 3
  • Year: 2011
  • Summary: This article reports on field experiments with 4 different rotations that are commonly used throughout Haryana in NW India (rice-wheat, cotton-wheat, pearl millet-wheat, cluster bean-wheat), where we assess wheat yield and chapatti quality measures with different crop establishment methods and input of micronutrients. In a series of experiments conducted on farmers' fields in 2007-2008 and 2008-2009 winter seasons, the addition of micronutrients and sulphur to wheat crops was used alongside the use of a common farmer practice, the use of farmyard manure (FM) and best practice inputs of N-fertilizer (150 kg N ha -1), P-fertilizer (26 kg P ha -1) and K-fertilizer (33 kg K ha -1). The application of FM with the recommended NPK treatment produced 9-13% more grain yield in the rice-wheat rotation when compared with the recommended NPK only treatment. Given that the farm sites used here had low levels of soil P, this may suggest that the recommended rate of 26 kg P ha -1 for the rice-wheat rotation is too low. The addition of FM did not improve any grain quality outcomes at any of the sites. There were no yield responses with S application with any of the rotations but the S input resulted in more wheat protein from all sites (average 8%). The addition of S also gave similar increases in grain hardness and the chapatti score. The inclusion of micronutrients (boron, copper, iron, zinc and manganese) with the recommended NPK treatment did not increase the grain yield at any of the sites when compared with the recommended NPK treatment, and sometimes, but not consistently, gave small responses with protein, grain hardness and chapatti score. In concurrent experiments wheat growth and chapatti quality were compared in zero till and conventionally sown systems, and with and without S fertilizer amendment. Here too there were no grain yield responses to S, and the protein, grain hardness and chapatti score were increased with S addition. Grain yields with zero till and conventional wheat were similar in the rice-wheat system and zero till sowing resulted in small increases in yield at all of the non-rice sites. The grain from the zero till treatments had higher protein (1-3%), grain hardness (3-10%) and chapatti score from all 4 rotations. Zero till has substantial adoption in the rice-wheat districts of Haryana but little farmer awareness and adoption in the areas where the other rotations are used. The data given here show that with zero tillage and an integrated practice of nutrient management farmers in Haryana can maintain grain yields of wheat whilst improving quality outcomes.
  • Authors:
    • Dalal, R. C.
    • Allen, D. E.
    • Wang, W. J.
    • Reeves, S.
    • Gibson, I.
  • Source: Soil & Tillage Research
  • Volume: 112
  • Issue: 2
  • Year: 2011
  • Summary: Conservation agricultural practices such as no-till (NT) and crop residue retention (CRR), and nutrient application, increases soil organic C (SOC) and are considered effective measures of C sequestration in soil. However, long-term effects of individual components of conservation agriculture and their interactions on SOC are rarely evaluated; as a result, conflicting findings of these practices on SOC are reported in the literature. We measured SOC and soil total N in a balanced factorial experiment, conducted on a Vertisol, consisting of tillage practices (conventional mechanical tillage, CT; and no-tillage, NT), crop residue management (crop residue burned, CRB; and crop residue retained, CRR) and N fertiliser application (no N, 30 kg N ha -1 year -1; and 90 kg N ha -1 year -1). The site, in a semiarid subtropical region, was cropped with wheat ( Triticum aestivum L.) except for 3 years of barley ( Hordeum vulgare L.), for 40 years using conservation practices. In general, tillage effects on SOC and soil total N were small. Crop residue and N fertiliser interactively increased SOC and total N stocks at 0-0.1 m depth and cumulative stocks at 0-0.2 m and 0-0.3 m depths; that is, CRR increased SOC and soil total N only when N fertiliser was applied, and fertilisation increased SOC and soil total N only under CRR treatment. Depletion of delta 13C values in CRR treatments and delta 15N values in N treatments strongly indicated the contribution of crop residue (and root biomass) and N fertiliser to soil organic matter in this Vertisol. From this study and previous findings from this site, it appears, however, the effects of crop residue retention and N fertiliser occurred in early years, and did not continually increase SOC and total soil N with increasing period of conservation practices.
  • Authors:
    • Allen, D. E.
    • Reeves, S.
    • Menzies, N. W.
    • Dalal, R. C.
    • Wang, W.
  • Source: Soil Science Society of America Journal
  • Volume: 75
  • Issue: 6
  • Year: 2011
  • Summary: Land-use change from perennial grasslands to cultivated croplands leads to reduced soil organic C (SOC) and total N. Among other factors, introduction of annual crops and soil disturbance by tillage may account for reduced amounts of SOC and total N. However, agricultural practices of no-till and N fertilizer application may maintain soil N in cropped soils. We measured soil N changes and N-use efficiency in a field experiment initiated in 1968, consisting of completely randomized tillage practices (conventional mechanical till [CT], and no-till [NT]), crop residue management (residue burned [RB], and residue retained [RR]), and N fertilization (0, 30, and 90 kg N ha -1) on a Vertisol (Ustic Pellusert) over 40 yr. Crops grown were mainly wheat ( Triticum aestivum L.) except for five barley ( Hordeum vulgare L.) crops early in the experiment. Significant effects of treatments on soil total N were primarily confined to the top 0.1-m depth. Soil total N exponentially declined in all treatments even though apparent fertilizer N recoveries during this period (1969-2008) were only 46 and 59% of N applied at 90 and 30 kg N ha -1, respectively. Mineral N in the soil profile (0-1.2 m) ranged from 68 to 496 kg N ha -1. Nitrogen-use efficiency was similar ( P=0.13) under CT and NT in this Vertisol. However, crop residue retention and a low rate of N application had greater N-use efficiency (35-40%) than RB and a high rate of N application (21-25%) under the annual cereal grain cropping system. If perennial grasslands are considered ecological benchmarks for agricultural sustainability, primarily through large root biomass that utilizes water and nutrients efficiently, then the challenge remains to develop cropping systems that successfully mimic grassland ecosystems.
  • Authors:
    • Dawson, J. C.
    • Murphy, K. M.
    • Huggins, D. R.
    • Jones, S. S.
  • Source: Organic Agriculture
  • Volume: 1
  • Issue: 2
  • Year: 2011
  • Summary: There is growing interest in breeding crop cultivars specifically for organic agriculture, based on recognized differences in environmental conditions and management in organic systems compared to conventional systems, and especially due to environmental heterogeneity among and within individual organic systems. There is a need to develop effective strategies for improving crop performance in organic systems through plant breeding. This study evaluated 12 diverse winter wheat breeding lines chosen from conventional and organic breeding nurseries, six historic varieties, and an experimental perennial wheat population under organic management in the Inland Pacific Northwest region of the USA. A randomized complete block design with three replications in two locations over 2 years was used. Based on an analysis of variance, significant genetic differences and crossover interactions across years were found for grain yield, grain percent nitrogen, grain total nitrogen, and aboveground biomass. There were no main effects of locations or location-by-genotype effects for these traits. Based on comparisons among these breeding lines, it appears that there is a possibility of selecting for performance across a limited ecological zone as top-yielding lines were the same in both locations. However, individual entries may have variable performance across years within a single location so selection for stability of performance over years is also necessary. Using an analysis of direct measures of grain yield and grain %N in each location-year combination and overall, we identified breeding lines with relatively high yield, acceptable grain protein, and stable performance over all four location-year combinations. The use of indirect measures or index selection to simultaneously select for grain yield and protein did not appear to be more effective than direct selection based on yield and grain %N measured under organic management.
  • Authors:
    • dos Santos, N. Z.
    • Dieckow, J.
    • Bayer, C.
    • Molin, R.
    • Favaretto, N.
    • Pauletti, V.
    • Piva, J. T.
  • Source: Soil & Tillage Research
  • Volume: 111
  • Issue: 2
  • Year: 2011
  • Summary: To improve C sequestration in no-till soils requires further development of crop rotations with high phytomass-C additions. The objectives of this study were (i) to assess long-term (17 years) contributions of cover crop- or forage-based no-till rotations and their related shoot and root additions to the accumulation of C in bulk and in physical fractions of a subtropical Ferralsol (20-cm depth); and (ii) infer if these rotations promote C sequestration and reach an eventual C saturation level in the soil. A wheat (Triticum aestivum L., winter crop)-soybean (Glycine max (L.) Merr, summer crop) succession was the baseline system. The soil under alfalfa (Medicago sativa L, hay forage) intercropped every three years with maize (Zea mays L., summer crop) had the highest C accumulation (0.44 Mg C ha(-1) year(-1)). The bi-annual rotation of ryegrass (Lolium multiflorum Lam., hay winter forage)-maize-ryegrass-soybean had a soil C sequestration of 0.32 Mg C ha(-1) year(-1). Among the two bi-annual cover crop-based rotations, the vetch (Vicia villosa Roth, winter cover crop)-maize-wheat-soybean rotation added 7.58 Mg C ha(-1) year(-1) as shoot plus root and sequestered 0.28 Mg C ha(-1) year(-1). The counterpart grass-based rotation of oat (Avena strigosa Schreb., winter cover crop)-maize-wheat-soybean sequestered only 0.16 Mg C ha(-1) year(-1), although adding 13% more C (8.56 Mg ha(-1) year(-1)). The vetch legume-based rotation, with a relative conversion factor (RCF) of 0.147, was more efficient in converting biomass C into sequestered soil C than oat grass-based rotation (RCF = 0.057). Soil C stocks showed a close relationship (R(2) = 0.72-0.98, P < 0.10) with root C addition, a poor relationship with total C addition and no relationship with shoot C addition. This suggests a more effective role of root than shoot additions in C accumulation in this no-till soil. Most of the C accumulation took place in the mineral-associated organic matter (71-95%, in the 0-5 cm layer) compared to the particulate organic matter. The asymptotic relationship between root C addition and C stocks in bulk soil and in mineral-associated fraction supports the idea of C saturation. In conclusion, forages or legume cover crops contribute to C sequestration in no-till tropical Ferrasols, and most of this contribution is from roots and stored in the mineral-associated fraction. This combination of soil and rotations can reach an eventual soil C saturation.
  • Authors:
    • Dubie, T. R.
    • Greenwood, C. M.
    • Godsey, C.
    • Payton, M. E.
  • Source: Southwestern Entomologist
  • Volume: 36
  • Issue: 1
  • Year: 2011
  • Summary: A long-term tillage study plot was sampled to evaluate the effects of tillage on soil-dwelling microarthropods. Soil (300 cm 3) was sampled on four dates during two growing seasons from conventional and no-till plots of winter wheat. Microarthropods were extracted using Tullgren funnels and enumerated into seven taxonomic categories: (1) Total abundance, (2) Oribatida, (3) Mesostigmata, (4) Prostigmata, (5) Astigmata, (6) Collembola, and (7) other invertebrates. Abundance within six of the seven groups was greater in no-till than conventionally tilled soil on seven of the eight sampling dates: (1) Total abundance in conventional till 6.441.68 and 21.395.35 in no-till, (2) Oribatida in conventional till 1.060.36 and 7.332.23 in no till, and (3) Other invertebrates in conventional till 4.500.82 and 10.672.85 in no till. The Mesostigmata and Collembola showed significant differences between conventionally tilled and no-till plots on multiple dates. In contrast, mites in the group Prostigmata were more abundant in conventionally tilled soil (3.891.13 versus 2.000.88 in no till). Abundance of soil microarthropods in no-till plots generally increased (21.395.35 in Season 1 to 42.424.59 in Season 2), which might indicate gradual recovery of the habitat. Assessments of soil quality in no-till agricultural systems should include evaluations of beneficial soil fauna such as microarthropods.
  • Authors:
    • Flower, K. C.
    • Jabran, K.
    • Wahid, A.
    • Siddique, K. H. M.
    • Farooq, M.
  • Source: Soil & Tillage Research
  • Volume: 117
  • Year: 2011
  • Summary: Crop yield potential with conservation agriculture (CA) in rainfed systems is often greater than with conventional tillage (CVT) systems, particularly where sub-optimal rainfall limits yield. However, the full potential is rarely achieved because of various biotic and abiotic constraints. Analysis of 25 experiments found a slight increase in CA crop yields over time relative to CVT, indicating that CA can compete with CVT on a purely crop production basis and also has well-established environmental benefits. Evolved weed resistance to herbicides remains one of the greatest challenges to CA yields and long-term sustainability, yet there are some successful management stories. Worldwide adoption of CA is increasing; however, uptake in some regions is slow or non-existent. A lack of information on the effects and interactions of minimal soil disturbance, permanent residue cover, planned crop rotations and integrated weed management, which are key CA components, can hinder its adoption. This is because these interactions can have positive and negative effects depending on regional conditions. The positive impacts should be exploited through systems research to enhance CA crop yields. A greater focus on the influence of residue and weed management components as well as breeding for varieties adapted to biotic and abiotic stresses often associated with CA is required.