• Authors:
    • Shi, X.
    • Luan, C.
    • Sui, P.
    • Chen, Y.
  • Source: Journal of Integrative Agriculture
  • Volume: 11
  • Issue: 6
  • Year: 2012
  • Summary: Weed control is one of the major constraint factors in crop production around the world. Field experiments were conducted during 2008-2009 under intercropping systems involving alfalfa ( Medicago sativa L.), sweet potato ( Ipomoea batatas [L.] Lam.), peanut ( Arachis hypogaea L.), and sunflower ( Helianthus annuus L.) in maize ( Zea mays L.) without any weeds control methods taken. The results demonstrate that maize||sunflower is most effective on weed suppression and that it also has a more competitively inhibitory effect on Xanthium compared with the other patterns by evaluating the Xanthium density and dry weight under different intercropping systems with maize. Maize||peanut, maize||alfalfa and maize||sweet potato intercrops have no apparent inhibitory effect on weeds. To further investigate the effect of maize||sunflower on weed control, indoor pot experiments were conducted by determining the effect of extractions on germination rate (GR), root vigor, MDA (malondialdehyde), SOD (superoxide dismutase) and POD (peroxidase) content of Xanthium. The results better prove that maize||sunflower extractions have more significant inhibitory effect on GR and young root vigor of Xanthium than maize monocrop extractions.
  • Authors:
    • Schlegel, A.
    • Halvorson, A.
  • Source: Agronomy Journal
  • Volume: 104
  • Issue: 5
  • Year: 2012
  • Summary: Limited irrigation management practices are being used in the Central Great Plains to conserve water by optimizing crop water use efficiency. Limited irrigation may reduce total crop biomass production and amount of crop residue returned to the soil. Crop residue production within four no-till (NT) crop rotations [continuous corn ( Zea mays L.) (CC); corn-winter wheat ( Triticum aestivum L.) (CW); corn-winter wheat-grain sorghum ( Sorghum bicolor L. Moench) (CWS); corn-winter wheat-grain sorghum-soybean [ Glycine max (L.) Merr.] (CWSSb)] was measured and changes in soil organic carbon (SOC) and total soil nitrogen (TSN) stocks were monitored for 10 yr. Crop residue yields varied with crop being produced and with rotation, as did residue N and C returned to the soil. The C/N ratio of the residue varied with crop. The SOC and TSN pools increased with time in all rotations. The rate of gain in SOC and TSN mass for each rotation was 717, 477, 335, and 270 kg SOC ha -1 yr -1 and 114, 92, 87, and 84 kg TSN ha -1 yr -1 for the CC, CW, CWS, and CWSSb rotations, respectively, in the 0- to 30.5-cm soil depth. The rate of change in SOC and TSN mass was lowest with CWSSb (8.7 Mg residue ha -1 yr -1) and highest with CC (12.0 Mg residue ha -1 yr -1). Approximately 6.8 to 7.6 Mg residue ha -1 yr -1 would be needed to maintain SOC stocks under limited irrigation.
  • Authors:
    • Jaskulski, D.
    • Osinski, G.
    • Jaskulska, I.
    • Madry, A.
  • Source: Fragmenta Agronomica
  • Volume: 29
  • Issue: 1
  • Year: 2012
  • Summary: Drawing on the statistical survey performed over 2010-2011 on 155 farms in the Kujawy and Pomorze region, there was evaluated cultivar diversity for basic field crops and it was compared in the sown crops of winter wheat, spring barley, winter triticale, rye, maize, winter rape, sugar beet and potato. The following were determined: the knowledge of crop cultivars sown by farmers on production plantations and the most frequently grown cultivars, their number to the number of plantations of that species, diversity and domination defined using the Shannon-Wiener and Simpson indices. It was found that on 15.8-43.4% plantations the cultivars were not known to the farmers, most in the sown crops of spring barley. The best knowledge was recorded for the cultivars of winter wheat, winter rape and potato. A high richness of cultivars, expressed with the number of cultivars to the number of plantations, concerned the crops of potato, sugar beet and maize and the lowest richness - rye. The highest cultivar diversity of crops occurred in the sown winter wheat, winter triticale, winter rape, corn and spring barley. The lowest diversity, however, at the same time, the highest cultivar dominance, was recorded for sugar beet, potato and rye. The highest share of a single cultivar in the sown crop of the species was reported for 'Californium' winter rape, 'Dankowskie Zote' rye and 'Lord' potato.
  • Authors:
    • Reicosky, D.
    • Porter, P.
    • Baker, J.
    • Ochsner, T.
    • Krueger, E.
  • Source: Agronomy Journal
  • Volume: 104
  • Issue: 4
  • Year: 2012
  • Summary: Recent proliferation of large dairies has prompted concern regarding environmental impacts of associated corn silage production and high-rate manure application. Our objectives were to compare environmental impacts and forage production of monocrop corn ( Zea mays L.) silage and rye ( Secale cereal L.)-corn silage double-crop systems with multiple corn planting dates and high-rate manure application near Morris, MN. From 2007 to 2009, corn for silage was seeded into a silt loam as a monocrop in early and mid-May and as a double-crop after rye in mid-May and early June. Manure was fall applied annually at average total N and P rates of 393 and 109 kg ha -1, respectively. Double-cropping reduced total forage dry matter (DM) yield 2 of 3 yr and reduced corn DM yield 15 to 25%. Soil NO 3-N to 90 cm accumulated at an average rate of 71 kg N ha -1 yr -1 with monocropping, but accumulation was not observed with double-cropping. Soil organic C concentration from 0 to 5 cm increased in the monocrop (18%) and double-crop (26%) systems over 3 yr. Average soil solution NO 3-N concentration was high with monocropping (52 mg L -1) and double-cropping (37 mg L -1), but estimated leaching load averaged only 8 kg ha -1 yr -1. Fall and spring ground cover was often less than 10% with monocropping but was usually greater than 30% with double-cropping. The primary environmental concerns identified for monocrop corn silage were soil NO 3-N buildup and inadequate ground cover. Double-cropping addressed each concern but often decreased forage production.
  • Authors:
    • Polyanskaya, N.
    • Suslov, S.
    • Kuchin, N.
  • Source: Ekonomika Sel'skokhozyaistvennykh i Pererabatyvayushchikh Predpriyatii
  • Issue: 3
  • Year: 2012
  • Summary: In 2009, production of leguminous and cereal grain crops in Russia's Nizhny Novgorod Oblast' totalled 1 432 400 tonnes, and the average crop yield was 2.44 tonnes/ha - the highest yield in 50 years. However extremely hot and dry weather conditions in 2010 caused a sharp reduction in harvest volumes, so that Nizhny Novgorod Oblast' had a total harvest of just 541 500 tonnes and an average crop yield of 1.36 tonnes/ha. 2010 harvest figures for the region were significantly lower than in 2006, when the total harvest volume was 1 169 900 tonnes and the average crop yield 2.05 tonnes/ha. Crop yields in Nizhny Novgorod Oblast' vary significantly between years, with yields being highly dependent on climate conditions. The greatest variation in yields occurs with maize, millet, and buckwheat crops. Strong variation in yields is also evident for wheat and leguminous crops, and moderate variation occurs in yields of rye, barley, and oats. For agricultural enterprises, the most significant factor influencing their production volumes and incomes is the structure of crops produced. The structure of crops produced in Nizhny Novgorod Oblast' has changed significantly since the pre-reform period, with a marked shift towards cultivation of food grade cereal grains, and away from production of feed crops. In 2010, wheat accounted for 56.8% of the region's total harvest, barley 21.9%, oats 10.7%, rye 7.6%, legumes 2.5%, triticale 0.4%, and groats crops 0.1%. Agricultural organizations continue to be the main cereal grain producers, despite increases in land areas used for cereal grain cultivation by private (peasant) farmers. In 2010, agricultural enterprises accounted for 92.2% of cereal grain production. Individual secondary farms account for only an insignificant proportion of grain crop production. Problems faced by enterprises operating in the region's cereal grain segment include a poor technical base, low rates of fertiliser application, and difficulties in securing suitably qualified workers. Approximately 80% of machines used by these enterprises have been in use for longer than their intended operating life. These problems have adverse effects on the efficiency of harvesting operations and on crop yields. It is important to address these issues if higher and more stable production volumes are to be achieved, and the profitability of crop production activities improved.
  • Authors:
    • Neumann, M.
    • Lacerda, M.
    • Lago, W.
  • Source: REVISTA BRASILEIRA DE ENGENHARIA AGRICOLA E AMBIENTAL
  • Volume: 16
  • Issue: 7
  • Year: 2012
  • Summary: The intensively increasing agricultural use of Distrito Federal soils may compromise their quality and trigger environmental problems in the region. Given this fact, the objective of this work was to study the soil quality (SQ) indicators, in areas under no tillage (PD), with diversified managements (corn-soybean rotation and bean-sorghum succession), at the Riberao Extrema watershed, Distrito Federal. Soil bulk density (Ds), flocculation index (GF), organic matter (MO), cation exchange capacity (CTC), microbial respiration (Rmic) and microbial biomass carbon (Cmic) were the attributes of SQ evaluated. Statistical analysis was performed using the statistical software Statistics Analysis System (SAS) and consisted of analysis of variance (ANOVA) followed by Tukey test for comparison of means. Results show that some of the evaluated SQ indicators were affected by different types of soil management under evaluation (Ds, Cmic and MO), while others were not sensitive to them (GF, CTC and Rmic). Positive correlation was found between MO and CTC of the soils in both investigated treatments, highlighting the importance of no tillage system on the chemical properties of soil.
  • Authors:
    • Pietrusiewicz, J.
    • Horn, R.
    • Lipiec, J.
    • Siczek, A.
  • Source: Soil & Tillage Research
  • Volume: 121
  • Year: 2012
  • Summary: Soil compaction affects pore structure and thereby plant root growth. Elongation and anatomy of seedling roots of wheat ( Triticum aestivum), barley ( Hordeum vulgare), rye ( Secale cereale), triticale ( Triticosecale Wittmack) and maize ( Zea mays) grown in uncompacted bulk field (U) and compacted headland (C) Orthic Luvisol developed from loess of the same field were compared. The seedlings were grown in a growth chamber for 7 days, in cores with undisturbed silt loam taken from 5 to 10 cm depths at compacted and uncompacted sites. Transverse root sections were taken from 25 to 30 mm behind the apex following imbedding in resin. Areas of cortex and vascular cylinder in the sections were determined using the Zeiss LSM Image Examiner. Total root length was smaller in C compared with U by, approximately, 50% for barley to 79% for triticale. Anatomical responses of the roots to soil compaction were related to the general shape of roots (circular or flattened), likely induced by the shape of pores. In the circular roots of wheat, rye and maize the primary anatomical response to soil compaction were the invaginations and associated cell deformation in the cortex. This was mostly pronounced in maize, with greater inherent root diameter. However, in the flattened roots of barley and triticale deformation of root cells was observed both in the cortex and vascular cylinder with less pronounced invaginations. Depending on plant species, the area of cortex and/or vascular cylinder decreased or increased in response to soil compaction. Total cross section area of roots increased in C compared to U among the small-grain cereals, from 9.5 in wheat to 132% in rye, while no differences could be detected in maize. The results indicate that the root elongation and anatomy exhibit considerable plasticity in response to soil compaction and strength of the local environment around the roots.
  • Authors:
    • Muni, R.
    • Saudan, S.
    • Aparbal, S.
    • Man, S.
  • Source: Archives of Agronomy and Soil Science
  • Volume: 58
  • Issue: 4
  • Year: 2012
  • Summary: The objective of the study was to determine the profitability and employment-generation potential of different cropping systems involving menthol mint ( Mentha arvensis L.) as a component of sequential/intercropping in comparison with the most common paddy-wheat-green gram cropping system. Field experiments were conducted at Lucknow, India (26°5′N, 80°5′E and 120 m above mean sea level) for three years from July 2004 to June 2007. Menthol mint yielded the maximum fresh shoot biomass and essential oil (21.0 t and 151 kg ha -1, respectively) grown after sweet basil ( Ocimum basillicum)-potato followed by paddy-potato-menthol mint (18.9 t and 136 kg ha -1, respectively) and maize-mustard-menthol mint (17.7 t and 131 kg ha -1, respectively). Net returns of all the menthol-mint-based cropping systems were 82.6-354% higher than traditional paddy-wheat-green gram cropping system. Maize-garlic-menthol mint+okra was found to be most profitable (77,200 Rs ha -1) followed by pigeon pea+sweet basil-menthol mint+okra (76,120 Rs ha -1). Employment-generation efficiency was much higher in cropping systems involving menthol mint and vegetable crops, the highest (2.21 man days ha -1 day -1) being in a maize-cauliflower-onion-menthol mint+okra cropping system.
  • Authors:
    • Chimbizi, A.
    • Chimphero, L.
    • Mwale, C.
    • Mhango, W.
    • Kambauwa, G.
    • Kabambe, V.
    • Ngwira, A.
    • Mapfumo, P.
  • Source: African Journal of Agricultural Research
  • Volume: 7
  • Issue: 6
  • Year: 2012
  • Summary: Maize ( Zea mays L.) is a major staple food in Malawi. However, low soil fertility resulting from low and inappropriate use of fertilizer practices, continuous monocropping and inappropriate crop residues management coupled with limited resources and droughts keep yields low. This had led to a quest for sustainable solutions such as maize-legume intercropping or rotation including more efficient use of crop residues in smallholder farming systems. Innovation platforms (IP) built around learning centres (LC) located on smallholder farmers' fields in target locations were used as an approach to disseminate integrated soil fertility management (ISFM) technologies and build capacity of farmers, extension staff and other stakeholders. Rotating maize with either groundnut or groundnut intercropped with pigeonpea increased maize grain yield (3678 and 3071 kg ha -1 respectively) compared to sole maize (2260 kg ha -1). These preliminary findings were linked to farmer assessment of technologies where farmers participating in the LCs expressed strong interest in the maize legume rotation technologies. Associated farmer field days outlined constraints underlying technology choice, information that is not usually considered in conjunction with on-farm experimentation. Although, the legumes were highly productive, farmers expressed worries about legume seed availability, disease incidences, weeds infestations and livestock damage. Participating farmers commonly manage residues by burning. Promotion and experimentation with more efficient use of legume residues have shown short-term positive impacts in efforts to promote scaling-out of best fit legume technologies. This study reports the value of multi-stakeholder partnering in scaling-out and evaluation of best fit legume technologies and adoption constraints.
  • Authors:
    • Subramanian, S.
    • Meyhofer, R.
    • Nyasani, J.
    • Poehling, H.
  • Source: Entomologia Experimentalis et Applicata
  • Volume: 142
  • Issue: 3
  • Year: 2012
  • Summary: The study aimed at determining thrips species composition and thrips population density on French bean planted as a sole crop and as an intercrop with either sunflower, Irish potato, or baby corn, in various combinations. Field experiments were conducted in two seasons to examine: (1) thrips population development and thrips species composition over time, (2) effect of intercrops on thrips population density and natural enemies, and (3) effect of intercrops on French bean yield. The experiments were conducted at the Kenya Agricultural Research Institute, Embu, Kenya in a randomized complete block design with four replicates. The thrips population on French beans increased with time. It showed a peak at the flowering stage then started declining when the crops were nearing senescence. French beans hosted four thrips species, Megalurothrips sjostedti (Trybom), Frankliniella schultzei (Trybom), Frankliniella occidentalis (Pergande), and Hydatothrips aldolfifriderici (Karny) (all Thysanoptera: Thripidae) in order of decreasing abundance. The main thrips species on Irish potato and sunflower was F. schultzei. Baby corn hosted only Frankliniella williamsi (Hood) and Thrips pusillus (Bagnall). A monocrop of French bean hosted more thrips than a French bean intercrop mix. Thrips natural enemies such as Orius spp. and Ceranisus spp. were recorded in all crop plants but in especially high numbers on French bean and baby corn, respectively. Plots with French bean alone had about 1.4 times higher yields compared to intercropped plots of French bean with sunflower and French bean with baby corn. However, the percentage of pods that could get rejected on the market due to thrips damage was highest on plots with French bean alone (68 and 63%) and lowest on plots with French bean and baby corn (35 and 37%) in the first and second seasons, respectively. This study showed that a complex of thrips is found in the field and its composition varies with crop stage and species. Intercropping French bean with other crops compromises on French bean yield but reduces damage to the French bean pods, thereby enhancing marketable yield.