• Authors:
    • Parandiyal, A.
    • Singh, S.
    • Arjun, P.
    • Singh, K.
    • Ashok, K.
    • Shakir, A.
    • Prasad, S.
    • Singh, R.
  • Source: Indian Journal of Soil Conservation
  • Volume: 33
  • Issue: 2
  • Year: 2005
  • Summary: Bunding and field levelling are the most preferred activities in the community-driven watershed projects in the semiarid region. In a two-year study carried out during June 1999 to June 2001 on a farmer's field in a ravinous watershed located in south-eastern Rajasthan, India, the effect of bunding and levelling on in situ moisture conservation and corresponding increase in grain and stover yields of chickpea, mustard, sorghum and soyabean was compared. These land treatments considerably improved profile moisture and crop yields during normal as well as deficit monsoon year. Results indicated that conservation measures can potentially stabilize crop production under dryland cropping systems. The land treatments and choice of crops were significant factors influencing economic productivity of land uses. In response to bunding alone and bunding with levelling, crop production increased by 46 and 112%, respectively, over control. Mustard cultivation recovered 76% of the bunding cost and 64% of the bunding+levelling cost in the first year only after imposing land treatments. It is concluded that in semiarid regions, appropriate conservation measures coupled with suitable land use planning result in convincing tangible benefits on short-terms basis, apart from their protective and long-term intangible benefits.
  • Authors:
    • Álvaro-Fuentes, J.
    • Arrúe, J. L.
    • López, M. V.
    • Moret, D.
  • Source: European Journal of Agronomy
  • Volume: 23
  • Issue: 1
  • Year: 2005
  • Summary: Most of the benefits from conservation tillage are attained by maintaining crop residues on the soil surface. However, the effectiveness of crop residues depends on their persistence in time and maintenance of sufficient residue cover can become difficult, especially when a long-fallow period is involved. In this study, we evaluate the effects of conventional tillage (CT) and two conservation tillage systems (reduced tillage, RT, and no-tillage, NT), under both continuous cropping (CC) and cereal-fallow rotation (CF), on the dynamics of surface barley residues during four fallow periods in a dryland field of semiarid Aragon. The CC system involves a summer fallow period of 5-6 months and the CF rotation a long-fallow of 17-18 months. Results indicate that the lack of residue-disturbing operations in NT makes this practice the best strategy for fallow management. With this tillage system, the soil surface still conserved a residue cover of 10-15% after long-fallowing and percentages of standing residues ranging from 20 to 40% of the total mass after the first 11-12 months. In both CT and RT, primary tillage operations had the major influence on residue incorporation, with percentages of cover reduction of 90-100% after mouldboard ploughing (CT) and 50-70% after chiselling (RT). Two decomposition models were tested, the Douglas-Rickman and the Steiner models. Our data indicate that the Steiner model described more accurately the decline of surface residue mass over the long-fallow period in the NT plots. Measured and predicted data indicate that, under NT, 80-90% of the initial residue mass is lost at the end of fallow and that 60-75% of this loss occurs during the first 9-10 months. Finally, the mass-to-cover relationship established in this study for barley residues could be used to predict soil cover from flat residue mass through the fallow period by using a single A(m) coefficient (0.00208 ha kg(-1)). (C) 2004 Elsevier B.V. All rights reserved.
  • Authors:
    • Cooke, F. T.,Jr.
    • Robinson, J. R. C.
    • Martin, S. W.
    • Parvin, D.
  • Source: Crop Management
  • Issue: April
  • Year: 2005
  • Summary: This study compared conventional, reduced tillage and no-till systems for cotton, maize, soyabean and sorghum in the Mississippi Delta. Most of the necessary parameters (e.g. yields, costs, equipment, field operations) were obtained from published budgets. The conventional systems typically involved subsoiling, discing, field cultivation, hipping and in-season cultivation. The reduced tillage systems substituted herbicides for heavy pre-plant soil preparation and in-season cultivation, while no-till systems substituted herbicides for all tillage operations. A whole-farm, mixed integer programming model was developed to determine the most profitable crop/tillage combinations at different acreage sizes, assess the actual economies of size (in dollars per acre) in row crop farming, determine the number of acres required to maximize economic viability, determine the best acreage size to minimize or optimize full-time labour, and evaluate profitability trade-offs, including farm programme eligibility, under different tillage systems.
  • Authors:
    • Zamfir, M. C.
    • Mitu, D.
  • Source: Probleme de agrofitotehnie teoretica si aplicata
  • Volume: 27
  • Issue: 2
  • Year: 2005
  • Summary: During 2001-03 in Teleorman, 14 Romanian maize hybrids (Campion, Rapsodia, Danubiu, Paltin, Olt, F. 376, Faur, Partizan, Octavian, Granit, F. 322, Milcov, Orizont and Vultur) were studied under different situations, such as irrigation and dryland, and under 3 types of drought during the maize vegetation: drought in the second part of summer (2001), drought in the first part of summer (2002), and long lasting drought (2003). Paltin, Campion, Rapsodia, Danubiu, Faur and Olt had a good behaviour under irrigated or dryland conditions, but Partizan, Orizont, Vultur, Octavian and Granit proved to be sensitive to drought. During dry years, the flowering delay (days) and the frequency of sterile plants had determined significant diminution of maize yield. The effects of drought on maize yield differed, depending on its type, intensity and way of action, under different stages of growth and development of the plants. Long lasting and pronounced drought over the whole period of maize vegetation resulted in the highest losses in yield (76-77%) compared to partial droughts during the second part of summer (62-65%) or during the first part of vegetation growth (26-30%). To reduce the negative effect of drought on maize, the cultivation of 2-3 hybrids with different earliness is recommended, which ensures a more efficient use of the distribution of rainfall during the maize vegetation as well as a reduced variation of harvest.
  • Authors:
    • Chivinge, O. A.
    • Rimawu, S.
    • Musambasi, D.
    • Mariga, I. K.
  • Source: Crop Research
  • Volume: 29
  • Issue: 1
  • Year: 2005
  • Summary: An on-farm field trial was conducted to assess the residual effects of 2 multi-purpose trees (Sesbania sesban and Sesbania macrantha) and 3 cowpea cultivars (IT 90K-59, IT 18 and Kavara) grown in Striga asiatica-infested fields for 2 consecutive seasons, 1998/99 and 1999/2000 summer seasons on maize grain yield and Striga asiatica density. A three-way maize hybrid, SC 501, was used as a test crop. At two of the sites, there were no significant differences in the number of emerged S. asiatica plants, while plots previously planted to maize/Kavara and S. sesban supported the least number of emerged S. asiatica plants at 8 and 10 weeks after crop emergence. Maize grain yield was statistically the same at Mungoriwo, while grain yield for the other two sites was lost because farmers bulked the trials before the researchers could take the records.
  • Authors:
    • Negrila, E.
    • Negrila, M.
  • Source: Probleme de Agrofitotehnie Teoretica si Aplicata
  • Volume: 27
  • Issue: 2
  • Year: 2005
  • Summary: Mineral fertilizer application on crops is one of the reliable ways of increasing soil productivity, improving the yield, quality and soil fertility. The nitrogen and phosphorus long-term fertilizer application in the cambic chernozem, under non-irrigated condition at the A.R.D.S. Teleorman, Romania, caused plants and soil modifications. The annual nitrogen and phosphorus (NP) fertilizer application (in 28 years) with moderate amounts and balanced ratios resulted in a yield increase of 12-17 kg wheat/1 kg NP, 7-11 kg maize/1 kg NP, 4-6 kg sunflower/1 kg NP, the smallest increase was during the drought years. The use of coefficient depends on crop and climatic evolution. The best nitrogen and phosphorus use efficiency was with wheat, followed by maize and sunflower. During the drought years, both elements use was reduced to half. It also had a positive influence on the crude protein content (4.08% for winter wheat and 3.76% for maize), on the other quality indices: technological flour indices, macro- and microelements. The P:Zn ratio of 57-100 also indicated a good ratio between the two elements which does not lead to occurrence of Zn deficiency. The values of N:S indicated some disorders in sulfur metabolism which can generate sulfur deficiency, especially in maize. The long-term fertilizer application (1977-2000) determined the improvement in soil fertility: maintenance of the humus content, the improvement of the mobile phosphorus content, of the saturation degree in alkali up to 83% and the reaction up to 5.9 pH, without mobile aluminium and Mn coming out. The absence of nitrogen and phosphorus fertilizers during 24 years led to soil fertility, yield and yield quality reduction.
  • Authors:
    • Peterson, G. A.
    • Westfall, D. G.
    • Ortega, R. A.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 36
  • Issue: 19/20
  • Year: 2005
  • Summary: In the West Central Great Plains of the United States, no-till management has allowed for increased cropping intensity under dryland conditions. This, in turn, has affected the carbon (C) and nitrogen (N) mineralization dynamics of these systems. In this region, moisture stress increases from north to south due to an increase in evapotranspiration (ET), resulting in a climatic gradient that affects cropping system management. The objectives of this study were to determine the interaction of cropping system intensification and climatic gradient (ET) on C and N mineralization and to determine if the presence or absence of crop residue on the soil surface affects C and net N mineralization. Two cropping systems, winter wheat-fallow (WF) ( Triticum aestivium L.) and winter wheat-corn (sorghum)-millet-fallow (WCMF) [ Zea mays (L.), Sorghum bicolor (L.) Moench, Panicum milaceum (L.)] were studied at three locations across this aforementioned ET gradient. The treatments had been in place for 8 yrs prior to sampling in the study. These results showed that the more intense cropping system (WCMF) had a higher laboratory C mineralization rate at two of the three locations, which the study concluded resulted from larger residue biomass additions and larger quantities of surface residue and soil residue at these locations (Soil residue is defined as recognizable crop residue in the soil that is retained on a 0.6 mm screen). However, no differences in N mineralization occurred. This is most likely due to more N immobilization under WCMF as compared to WF. Presence or absence of crop residue on the surface of undisturbed soil cores during incubation affected potential C and net N mineralization more than either cropping system or location. Soil cores with the surface residue intact mineralized as much as 270% more C than the same soils where the surface crop residue had been removed. In laboratory studies evaluating the relative differences in cropping systems effects on C and N mineralization, the retention of crop residue on the soil surface may more accurately access the cropping system effects.
  • Authors:
    • Jayanthi, C.
    • Shekinah, D. E.
    • Sankaran, N.
  • Source: Journal of Sustainable Agriculture
  • Volume: 25
  • Issue: 3
  • Year: 2005
  • Summary: In a small-scale resource-poor farm, modest increments in productivity are no longer sufficient to justify the investment of scarce resources. Integrated farming systems with multiple enterprises pave the way for realizing increased productivity, profitability and sustainability in small farms of the developing countries. A study conducted at Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India from July 2000 to March 2002 to optimize enterprise combination, increase employment and bring about maximum bioresource utilization and residue recycling for a 1-ha farm of the dryland tract of the western zone of Tamil Nadu compared four farming system combinations: FS 2 (crop+pigeon+goat+agroforestry+farm pond), FS 3 (crop+pigeon+buffalo+agroforestry+farm pond), and FS 4 (crop+pigeon+goat+buffalo+agroforestry+farm pond) with FS 1 (sorghum only) as the reference system. The results indicated the following: crop (0.80 ha) fertilized with buffalo manure produced on the farm, with pigeon (10 pairs on 0.01 ha), goat (5:1 female:male on 0.02 ha), buffalo (2 milking buffaloes+1 calf on 0.03 ha), agroforestry (0.10 ha) and farm pond (0.04 ha) was the profitable system enterprise that generated higher employment year-round. This system also facilitated the maximum recycling of resources and residues generated on the farm among the enterprises. The output and the waste of one enterprise served as input to another. The nutritive value of the system in terms of carbohydrate, protein and fat was also highest with this enterprise combination. Thus, FS 4 seems to be the best enterprise combination as revealed by the physical indicators. However, since the purchase and maintenance of buffalo enterprise involves higher costs, for farmers who have limited cash for investment, linkage of crop (0.80 ha) with pigeon (10 pairs on 0.01 ha), goat (5:1 female:male on 0.05 ha), agroforestry (0.10 ha) and farm pond (0.04 ha) is suggested as the alternative farming system for sustainability instead of conventional cropping alone.
  • Authors:
    • Rosenberg, N. J.
    • Brown, R. A.
    • Thomson, A. M.
    • Izaurralde, R. C.
    • Benson, V.
  • Source: Climatic Change
  • Volume: 69
  • Issue: 1
  • Year: 2005
  • Summary: Here we simulate dryland agriculture in the United States in order to assess potential future agricultural production under a set of general circulation model (GCM)-based climate change scenarios. The total national production of three major grain crops - corn, soybeans, and winter wheat - and two forage crops - alfalfa and clover hay - is calculated for the actual present day core production area (CPA) of each of these crops. In general, higher global mean temperature (GMT) reduces production and higher atmospheric carbon dioxide concentration ([CO 2]) increases production. Depending on the climatic change scenarios employed overall national production of the crops studied changes by up to plus or minus 25% from present-day levels. Impacts are more significant regionally, with crop production varying by greater than 50% from baseline levels. Analysis of currently possible production areas (CPPAs) for each crop indicates that the regions most likely to be affected by climate change are those on the margins of the areas in which they are currently grown. Crop yield variability was found to be primarily influenced by local weather and geographic features rather than by large-scale changes in climate patterns and atmospheric composition. Future US agronomic potential will be significantly affected by the changes in climate projected here. The nature of the crop response will depend primarily on to what extent precipitation patterns change and also on the degree of warming experienced.
  • Authors:
    • Hanna, W. W.
    • Timper, P.
  • Source: Journal of Nematology
  • Volume: 37
  • Issue: 2
  • Year: 2005
  • Summary: Pearl millet ( Pennisetum glaucum) has potential as a grain crop for dryland crop production in the southeastern United States. Whether or not pearl millet will be compatible in rotation with cotton ( Gossypium hirsutum), corn ( Zea mays), and peanut ( Arachis hypogaea) will depend, in part, on its host status for important plant-parasitic nematodes of these crops. The pearl millet hybrid 'TifGrain 102' is resistant to both Meloidogyne incognita race 3 and M. arenaria race 1; however, its host status for other plant-parasitic nematodes was unknown. In this study, the reproduction of Belonolaimus longicaudatus, Paratrichodorus minor, Pratylenchus brachyurus, and Meloidogyne javanica race 3 on pearl millet ('HGM-100' and TifGrain 102) was compared relative to cotton, corn, and peanut. Separate greenhouse experiments were conducted for each nematode species. Reproduction of B. longicaudatus was lower on peanut and the two millet hybrids than on cotton and corn. Reproduction of P. minor was lower on peanut and TifGrain 102 than on cotton, corn, and HGM-100. Reproduction of P. brachyurus was lower on both millet hybrids than on cotton, corn, and peanut. Reproduction of M. javanica race 3 was greater on peanut than on the two millet hybrids and corn. Cotton was a nonhost. TifGrain 102 was more resistant than HGM-100 to reproduction of B. longicaudatus, P. minor, and M. javanica. Our results demonstrated that TifGrain 102 was a poor host for B. longicaudatus and P. brachyurus (Rf