• Authors:
    • Prakash, V.
    • Pandey, S. C.
    • Kundu, S.
    • Bhattacharyya, R.
    • Srivastva, A. K.
    • Gupta, H. S.
  • Source: Soil Research
  • Volume: 47
  • Issue: 6
  • Year: 2009
  • Summary: We analysed results of a long-term experiments, initiated in 1973 on a sandy loam soil under rainfed condition and in 1995-96 on a silty clay loam soil under irrigated condition, to determine the influence of using different combinations of mineral fertiliser (NPK) and fertiliser+farmyard manure (FYM) at 10 Mg/ha on soil organic carbon (SOC) content and its changes in the 0-0.45 m soil depth. Fertilisation always caused a net gain in SOC stock. Such gain was positively proportional to the amount of C incorporated into the soils. Concentration of SOC in the 0-0.45 m depth increased by 44% in NPK+FYM treated plots compared with NPK (44.4 Mg C/ha) after 32 years under rainfed condition and by 14% in the NPK+FYM treated plots compared with NPK (41.76 Mg C/ha) after 9 years under irrigation. Mean (across treatments) total C added under the rainfed and irrigated systems was 2.67 and 3.03 Mg/ha.year, respectively. It was estimated that ~20 and 25% of the gross C input contributed towards the increase in SOC content under the rainfed and irrigated systems, respectively. Carbon loss from native soil organic matter (SOM) averaged ~61 and 261 kg C/ha.year under the rainfed and irrigated systems, respectively. Furthermore, mean stabilisation of added C in the plots under the rainfed condition (~16%) was higher than that (~13%) observed under the irrigated condition. Conversion of total added C to SOC was similar in the NPK and NPK+FYM treated plots under both growing conditions. In the NPK+FYM plots, ~38 and 29% of the C added through FYM was accounted for in the form of total SOC under the rainfed and irrigated conditions, respectively. The estimated quantity of biomass C required to maintain equilibrium SOM content under the rainfed and irrigated systems was 0.29 and 1.08 Mg/ha.year. The total annual C input by the soybean-wheat rotation in the unfertilised control plots under rainfed condition was 0.87 Mg/ha.year and with N fertiliser only under the irrigated condition was 1.75 Mg/ha.year. Thus, SOC augmentation under long-term soybean-wheat cropping was due to higher annual C input than the required amount to maintain equilibrium SOM content. Although FYM addition along with NPK improved total SOC stock and carbon sequestration potential, it did not encourage the stabilisation rate of added C. Hence, C stabilisation that takes into account the total C added in the system is a better indicator of assessing SOC sequestration. In summary, mineral fertilisation improved C sequestration capacity of soybean-wheat system in the Indian Himalayas and manure addition along with mineral fertilisers further improved it.
  • Authors:
    • Deshmukh, R. G.
    • Rathod, V. J.
    • Pawar, M. D.
  • Source: Journal of Soils and Crops
  • Volume: 19
  • Issue: 2
  • Year: 2009
  • Summary: To study the cropping sequences adopted by farmers in selected area, and study the economics of different cropping sequences, the resource productivity and use efficiency in different cropping sequences this study was undertaken in the three districts of Western Vidarbha viz., Buldhana, Washim and Akola. The study was based on secondary data. The required data were collected from Agricultural Price Scheme (APC) located in the Department of Agricultural Economics and Statistics, Dr. PDKV, Akola. Out of 220 farmers covered by APC scheme in the three districts of Western Vidharbha, the farmers who grew kharif as well as rabi crops in season were purposively selected for study. In all 101 farmers were selected. Cropping pattern followed in the study. In all 101 farmers were selected. Cropping pattern followed in the study area was diversified in nature, cotton, jowar and mung crops dominated the cropping pattern. Other crops like tur, udid, soybean were also grown on selected holdings. Gram and wheat crop occupied 18.12 and 2.89 per cent of gross cropped area. Net return of Cost "C" were observed the highest in cotton-fallow i.e. Rs. 5684.34 followed by Cotton+tur-Fallow Rs. 4052.22 and Soybean-Fallow Rs. 3570.55. The regression analysis indicated that variables viz., area under crop, machine labour, nitrogen were found to be positive and significant. Bullock labour in case of Jowar-Fallow i.e. -1.33* was negative and significant thereby indicating the use of these inputs decrease the values of gross output. The marginal value product (MVP) to factor cost ratio indicate optimum resources use efficiency of a particular input. The ratio of MVP to factor cost for area under crop was found to be greater than unity which inferred that this resource was underutilized in all cropping sequences.
  • Authors:
    • Yang, Y.
    • Reddy, N.
  • Source: Bioresource Technology
  • Volume: 100
  • Issue: 14
  • Year: 2009
  • Summary: This paper reports the development of natural cellulose technical fibers from soybean straw with properties similar to the natural cellulose fibers in current use. About 220 million tons of soybean straw available in the world every year could complement the byproducts of other major food crops as inexpensive, abundant and annually renewable sources for natural cellulose fibers. Using the agricultural byproducts as sources for fibers could help to address the concerns on the future price and availability of both the natural and synthetic fibers in current use and also help to add value to the food crops. A simple alkaline extraction was used to obtain technical fibers from soybean straw and the composition, structure and properties of the fibers was studied. Technical fibers obtained from soybean straw have high cellulose content (85%) but low% crystallinity (47%). The technical fibers have breaking tenacity (2.7 g/den) and breaking elongation (3.9%) higher than those of fibers obtained from wheat straw and sorghum stalk and leaves but lower than that of cotton. Overall, the structure and properties of the technical fibers obtained from soybean straw indicates that the fibers could be suitable for use in textile, composite and other industrial applications.
  • Authors:
    • Salado-Navarro, L. R.
    • Sinclair, T. R.
  • Source: Agricultural Systems
  • Volume: 102
  • Issue: 1/3
  • Year: 2009
  • Summary: Cropping schemes have developed in east-central Argentina for rainfed soybean (Glycine max Merr.) production that invariably employ no-tillage management. Often these schemes include growing soybean in a sequence of crops including wheat ( Triticum aestivum L.) and maize ( Zea mays L.). The full impact of various rotation schemes on soil water balance through a sequence of seasons has not been explored, although the value of these rotations has been studied experimentally. The objective of this work was to investigate through simulations, potential differences in temporal soil water status among rotations over five years. In this study, mechanistic models of soybean (Soy), maize (Maz), and wheat (Wht) were linked over a five-years period at Marcos Juarez, Argentina to simulate soil water status, crop growth, and yield of four no-till rotations (Soy/Soy, Soy/Wht, Soy/Maz, and Soy/Maz/Wht). Published data on sowing dates and initial soil water contents in the first year from a no-till rotation experiment were used as inputs to the model. After the first year, soil water status output from the model was used to initiate the next crop simulation in the sequence. The results of these simulations indicated a positive impact on soil water balance resulting from crop residue on the soil surface under no-till management. Continuous soybean and the two-year soybean/maize rotation did not efficiently use the available water from rainfall. Residue from maize was simulated to be especially effective in suppressing soil evaporation. Thus, the Soy/Maz simulation results indicated that this rotation resulted in enhanced soil water retention, increased deep water percolation, and increased soybean yields compared with continuous soybean crops. The simulated results matched well with experimental observations. The three-crop rotation of Soy/Maz/Wht did not increase simulated soybean yields, but the additional water retained as a result of decreased soil evaporation resulting from the maize residue allowed the addition of a wheat crop in this two-year rotation. Simulated soybean yields were poorly correlated with both the amount of soil water at sowing and the rainfall during the cropping period. These results highlight the importance of temporal distribution of rainfall on final yield. These models proved a valuable tool for assessing the consequences of various rotation schemes now being employed in Argentina on temporal soil water status, and ultimately crop yield.
  • Authors:
    • Sandor, M.
    • Domuta, C.
    • Samuel, A. D.
    • Vuscan, A.
  • Source: Research Journal of Agricultural Science
  • Volume: 41
  • Issue: 2
  • Year: 2009
  • Summary: Agricultural practices that reduce soil degradation and improve agricultural sustainability are needed particularly for preluvosoil. No-tillage planting causes minimal soil disturbance and combined with crop rotation may hold potential to meet these goals. Soil enzyme activities can provide information on how soil management affects the soil potential to perform processes, such as decomposition and nutrient cycling. Soil enzyme activities (actual and potential dehydrogenase, catalase, acid and alkaline phosphatase) 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) and crop rotation (2- and 6-crop rotations) experiment. Each activity in both non-tilled and conventionally tilled soil under all crops of both rotations decreased with increasing sampling depth. No-till - in comparison with conventional tillage - resulted in significantly higher soil enzymatic activities in the 0-20- and in significantly lower activities in the deeper layers. The soil under maize or wheat was more enzyme-active in the 6- than in the 2-crop rotation. In the 2-crop rotation, higher enzymatic activities were recorded under wheat than under maize. The enzymatic indicators of soil quality were calculated from the values of enzymatic activities determined in the plots of the 6-crop rotation. The results obtained show that the different hierarchies of the six plots as registered in 2008 may be related to the different nature of crops and kind of fertilisers. This means that by determination of enzymatic activities, valuable information can be obtained regarding fertility status of soils.
  • Authors:
    • Khating, L. E.
    • Shirale, S. T.
  • Source: Annals of Plant Physiology
  • Volume: 23
  • Issue: 1
  • Year: 2009
  • Summary: A field experiment was conducted on clay soil (Typic Haplusterts) of MAU, Parbhani during 2002-03 to study the effect of application of organic, inorganic and organic combined with inorganic nutrient sources on yield of various cropping systems, NPK uptake and balance in soil. Recommended dose of fertilizers and combined application of glyricidia @1.5 t ha -1+25% RDF increased grain yield and N, P, K uptake. The highest total grain yield (2335 kg ha -1) was recorded by RDF fallowed by glyricidia @1.5 t ha -1+25% RDF (2213 kg ha -1) and it was at par with each other. The cropping systems sorghum+pigeonpea recorded highest yield (2438 kg ha -1). The maximum N, P and K uptake (142.16, 23.92 and 63.71 kg ha -1 respectively) was recorded with the soybean+pigeonpea cropping system. There, was more buildup of available N, P and K in soil with soybean+pigeonpea cropping system with FYM followed by glyricidia.
  • Authors:
    • Pieterse, P. J.
    • Zhou, M.
    • Tagwira, F.
    • Shoko, M. D.
  • Source: World Journal of Agricultural Sciences
  • Volume: 5
  • Issue: 1
  • Year: 2009
  • Summary: The use of non-destructive devices like Delta-T-Leaf-Area-Meter and Canegro Models can help farmers to manage their cane crops and have an understanding of the importance of measurement of physiological parameters so as to maximize cane and sugar yields. This study was conducted on sandy clay loams of the lithosol group under the Zimbabwe soil classification system at The Zimbabwe Sugar Association Experiment Station (ZSAES). The main aim of this study was to establish the most economic rate of N fertilizer when vegetable and grain soybean are used as fallow crops in sugarcane production systems. The following cane parameters were measured: LAI, biomass, N in leaves and sugarcane and sugar yields. Sugarcane variety N14 was used in the experiment. Post vegetable soybean cane topdressed with 80 kg Nha 1 had the greatest LAI at 150 DAE. The highest biomass was realized on sugarcane topdressed with 80 and 120 kg Nha 1. At final tiller stability post vegetable cane top dresses with 80 kg Nha 1 had the most tiller population. N in leaves and cane and sugar yields were also highest on post vegetable soybean cane and topdressed with kg Nha 1. Tiller density or population and biomass production are important crop variables that are used to estimate the final cane stalk population and sucrose yields. So farmers can top-dress their cane with 80 kg Nha 1 when vegetable soybean are used as fallow crops. This will help them save about 40 kg Nha 1.
  • Authors:
    • Rufty, T.
    • Smyth, T. J.
    • Novais, R. F.
    • Correa, T. F. C.
    • Silva, I. R.
    • Silva, E. F.
    • Gebrim, F. O.
    • Nunes, F. N.
  • Source: Revista Brasileira de Ciência do Solo
  • Volume: 33
  • Issue: 1
  • Year: 2009
  • Summary: The protective effect of cations, especially Ca and Mg, against aluminium (Al) rhizotoxicity was extensively investigated in the last decades. The mechanisms by which the process occurs are however only beginning to be elucidated. Six experiments were carried out to characterize the protective effect of Mg application in relation to timing, location and crop specificity: Experiment 1 - Protective effect of Mg compared to Ca; Experiment 2 - Protective effect of Mg on distinct root classes of 15 soyabean genotypes; Experiment 3 - Effect of timing of Mg supply on the response of soyabean cultivars to Al; Experiment 4 - Investigating whether the Mg protective effect is apoplastic or simplastic using a split-root system; Experiment 5 - Protective effect of Mg supplied in solution or foliar spraying; and Experiment 6 - Protective effect of Mg on Al rhizotoxicity in other crops. It was found that the addition of 50 mmol litre -1 Mg to solutions containing toxic Al increased Al tolerance in 15 soyabean cultivars. This caused soyabean cultivars known as Al-sensitive to behave as if they were tolerant. The protective action of Mg seems to require constant Mg supply in the external medium. Supplying Mg up to 6 h after root exposition to Al was sufficient to maintain normal soyabean root growth, but root growth was not recovered by Mg addition 12 h after Al treatments. Magnesium application to half of the root system not exposed to Al was not sufficient to prevent Al toxicity on the other half exposed to Al without Mg in rooting medium, indicating the existence of an external protection mechanism of Mg. Foliar spraying with Mg also failed to decrease Al toxicity, indicating a possible apoplastic role of Mg. The protective effect of Mg appeared to be soyabean-specific since Mg supply did not substantially improve root elongation in sorghum, wheat, maize, cotton, rice, or snap bean when grown in the presence of toxic Al concentrations.
  • Authors:
    • Venkateswarlu, B.
    • Vittal, K. P. R.
    • Srinivasarao, C.
    • Kundu, S.
    • Wani, S. P.
    • Sahrawat, K. L.
    • Marimuthu, S.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 40
  • Issue: 15/16
  • Year: 2009
  • Summary: Soil carbon (C) pool plays a crucial role in the soil's quality, availability of plant nutrients, environmental functions, and global C cycle. Drylands generally have poor fertility and little organic matter and hence are candidates for C sequestration. Carbon storage in the soil profile not only improves fertility but also abates global warming. Several soils, production, and management factors influence C sequestration, and it is important to identify production and management factors that enhance C sequestrations in dryland soils. The objective of the present study was to examine C stocks at 21 sites under ongoing rainfed production systems and management regimes over the last 25 years on dominant soil types, covering a range of climatic conditions in India. Organic C stocks in the soil profiles across the country showed wide variations and followed the order Vertisols > Inceptisols > Alfisols > Aridisols. Inorganic C and total C stocks were larger in Vertisols than in other soil types. Soil organic C stocks decreased with depth in the profile, whereas inorganic C stocks increased with depth. Among the production systems, soybean-, maize-, and groundnut-based systems showed greater organic C stocks than other production systems. However, the greatest contribution of organic C to total C stock was under upland rice system. Organic C stocks in the surface layer of the soils increased with rainfall (r=0.59*), whereas inorganic C stocks in soils were found in the regions with less than 550 mm annual rainfall. Cation exchange capacity had better correlation with organic C stocks than clay content in soils. Results suggest that Indian dryland soils are low in organic C but have potential to sequester. Further potential of tropical soils to sequester more C in soil could be harnessed by identifying appropriate production systems and management practices for sustainable development and improved livelihoods in the tropics.
  • Authors:
    • Suyker, A. E.
    • Verma, S. B.
  • Source: Agricultural and Forest Meteorology
  • Volume: 149
  • Issue: 3/4
  • Year: 2009
  • Summary: We have been making year-round measurements of mass and energy exchange in three cropping systems: (a) irrigated continuous maize, (b) irrigated maize-soybean rotation, and (c) rainfed maize-soybean rotation in eastern Nebraska since 2001. In this paper, we present results on evapotranspiration (ET) of these crops for the first 5 years of our study. Growing season ET in the irrigated and rainfed maize averaged 548 and 482 mm, respectively. In irrigated and rainfed soybean, the average growing season ET was 452 and 431 mm, respectively. On average, the maize ET was higher than the soybean ET by 18% for irrigated crops and by 11% for rainfed crops. The mid-season crop coefficient Kc (=ET/ET 0 and ET 0 is the reference ET) for irrigated maize was 1.030.07. For rainfed maize, significant dry-down conditions prevailed and mid-season Kc was 0.840.20. For irrigated soybean, the mid-season Kc was 0.980.02. The mid-season dry down in rainfed soybean years was not severe and the Kc (0.900.13) was only slightly lower than the values for the irrigated fields. Non-growing season evaporation ranged from 100 to 172 mm and contributed about 16-28% of the annual ET in irrigated/rainfed maize and 24-26% in irrigated/rainfed soybean. The amount of surface mulch biomass explained 71% of the variability in non-growing season evaporation totals. Water use efficiency (or biomass transpiration efficiency), defined as the ratio of total plant biomass ( YDM) to growing season transpiration ( T) was 5.200.34 and 5.220.36 g kg -1, respectively for irrigated and rainfed maize crops. Similarly, the biomass transpiration efficiency for irrigated and rainfed soybean crops was 3.210.35 and 2.960.30 g kg -1. Thus, the respective biomass transpiration efficiency of these crops was nearly constant regardless of rainfall and irrigation.