• Authors:
    • Launay, M.
    • Tourdonnet, S. de
    • Shili-Touzi, I.
    • Dore, T.
  • Source: Field Crops Research
  • Volume: 116
  • Issue: 3
  • Year: 2010
  • Summary: The introduction of a living cover crop during a cash crop growth cycle (relay intercropping) and its maintenance after the cash crop harvest may help to preserve biodiversity, increase soil organic matter content and carbon sequestration and provide other ecosystem services, such as natural pest regulation or nutrient recycling, by increasing useful biotic interactions within the agroecosystem. We studied the impact of various approaches to manage a red fescue cover crop in a winter wheat crop in terms of light, water and nitrogen competition, using the STICS crop model adapted for intercropping. The STICS model for wheat/fescue intercropping was first evaluated on two years of experimental data obtained in the field. It gave satisfactory statistical results for the prediction of dry matter, leaf area index (LAI) and nitrogen accumulation in the two species, and for nitrogen and water dynamics in the soil. By simulating unmeasured variables, such as transpiration, the model improves our understanding of the performance of the intercrop in the field. For example, we showed that the intercropping system was more efficient that wheat grown as a sole crop, in terms of nitrogen accumulation and decreasing soil nitrogen levels before the leaching period. However, it also resulted in lower wheat yields. We then used the STICS model to compare four intercropping management scenarios differing in terms of the date of red fescue emergence, over 35 climatic years. We found that, in most climatic scenarios, the emergence of the fescue crop during the late tillering phase of the wheat crop gave the best compromise between wheat yield overall nitrogen accumulation and radiation interception.
  • Authors:
    • Miah, M. N. A.
    • Paul, G. C.
    • Siddique, M. A. B.
    • Amanullah, A. S. M.
  • Source: Pakistan Sugar Journal
  • Volume: 25
  • Issue: 4
  • Year: 2010
  • Summary: An experiment was conducted at Regional Sugarcane Research Station (RSRS), Thakurgaon during 2005-06 and 2006-07 cropping seasons to assess effects of different levels of irrigation and split application of N-K fertilizers in sugarcane (var. Isd 36) intercropped with potato (var. Dimond). The intercrop, potato received recommended fertilizer as usual. Application of Urea and Potash (N-K fertilizers) in two splits (B 1) produced highest number of tiller, millable cane and also highest yield in both levels of irrigation in both years. Though the difference was not significant over B 2 and B 3. But irrigation level A 1 (six light irrigation with 65 mm effective rainfall) had significant difference over A 2 (five comparatively deep irrigation with same effective rainfall). Highest number of tiller (215.3*10 3 ha -1), millable cane (114.7*10 3 ha -1) and cane yield (109.9 t ha -1) were produced by the treatment B 1 under A 1 level of irrigation in the crop year 2006-07. Hence split application of N-K fertilizers with two equal splits applied at plantation and at 145 days after plantation and also light irrigation, 6 to 7 number with total amount of 460-500 mm including effective rainfall may be preferred for loamy and sandy loam soils.
  • Authors:
    • Sujatha, S.
    • Bhat, R.
  • Source: Agricultural Water Management
  • Volume: 97
  • Issue: 7
  • Year: 2010
  • Summary: A 5-year field trial to assess the impact of microsprinkler irrigation and nutrition on vanilla grown as intercrop in arecanut plantation was conducted on a laterite soil. Pooled analysis indicated that microsprinkler irrigation at 1.0 Epan resulted in significantly higher green bean yield (842 kg ha -1) than 0.75 Epan (579 kg ha -1). Organic manure application in the form of vermicompost (720 kg ha -1) and FYM (768 kg ha -1) and recommended NPK (718 kg ha -1) produced green bean yield at par with recycling of gliricidia prunings (625 kg ha -1). Irrigation at 1.0 Epan proved superior by registering maximum benefit:cost (B:C) ratio of 2.25 compared to 1.62 at 0.75 Epan. The highest B:C ratio was obtained with recommended NPK (2.27) followed by recycling of gliricidia prunings (2.10), vermicompost (1.87), vermicompost+arecanut husk mulching (1.80) and FYM (1.64). The soil pH increased by 0.4 units in 2008 compared with the pre-experimental soil pH of 5.6 in 2004. Nutrition alone and in combination with irrigation had significant impact on soil pH. Organic manure application increased the soil pH (6.1-6.2) significantly over recommended NPK (5.6) at the end of experiment in 2008. Significant variation in soil organic carbon (SOC) was noticed due to different nutrition treatments. Application of vermicompost and FYM significantly increased the SOC content by 38-54% in 2008 over initial levels in 2004. Bray's P availability was influenced by nutrition and its interaction with irrigation. Application of FYM continuously for 4 years has resulted in significant increase in Bray's P content (41.3 mg kg -1) compared to other nutrition treatments (9.4-17.2 mg kg -1). Irrigation equivalent to 0.75 Epan (223 mg kg -1) increased the K availability significantly over 1.0 Epan (172 mg kg -1). The K availability was significantly higher in recommended NPK (416 mg kg -1) than in other organic treatments (98-223 mg kg -1) at 0-30 cm soil depth. Overall, vanilla responded well to irrigation and nutrition in arecanut-based cropping system with a better economic output and improved soil fertility.
  • Authors:
    • Pires, C. S. S.
    • Medeiros, M. A. de
    • Gravina, C. S.
    • Langer, L. F.
    • Cavalcante, K. R.
    • Togni, P. H. B.
    • Fontes, E. M. G.
    • Sujii, E. R.
  • Source: Arquivos do Instituto Biologico Sao Paulo
  • Volume: 77
  • Issue: 4
  • Year: 2010
  • Summary: The adoption of cultural practices such as companion plants and the kind of irrigation system can benefit the community of natural enemies in the agroecosystem due to the increase of more favorable microhabitats available and as a source of alternative resources, mainly in periods of low precipitation. This study evaluated how the tomato+coriander intercrop and the kind of irrigation (drip and sprinkler) could benefit the community of natural enemies in the tomato agroecosystem. This work was carried out in the experimental field of Embrapa Hortalicas, Gama, DF, from September to November 2008. The tomatoes were planted in monoculture or with coriander (companion plant) and irrigated by drip and sprinkler irrigation (three replicates per treatment), forming two groups of experimental plots according to the kind of irrigation. The community of natural enemies was sampled by the direct observation of specimens on 20 tomatoes plants per plot and in the treatments. Coriander plants were shaken over a plastic tray for collection of insects. The abundance, richness and diversity of natural enemies were higher in tomato+coriander plots, regardless of the irrigation system. We observed more species of natural enemies in tomato monoculture plots when it was irrigated by sprinkler irrigation. However, the cultural practices adopted had a different effect on each species or group of species. Therefore, in periods of low precipitation, the tomato+coriander consortium associated with sprinkler irrigation can enhance the conservation of natural enemies in the organic tomato agroecosystem.
  • Authors:
    • Paula Junior, T. J. de
    • Vieira, R. F.
    • Teixeira, H.
  • Source: Informe Agropecuario Pages:
  • Volume: 31
  • Issue: 254
  • Year: 2010
  • Summary: Despite the growth of bean production, those from small farms still accounts for significant percentage of the total production. Most produced are from Minas Gerais. Maximizing efficiency and minimizing production costs are important factors to increase the profits of small producers. The use of technology and exploitation of natural resources should guide the actions of farmers. Planting dates, cultivars, row spacing and plant density, cropping systems, maize-bean intercropping, irrigation, weed control, pests and diseases as well as practical information technologies from research that aimed at increasing the income of the farmer with the cultivation of beans should be addressed.
  • Authors:
    • Gary, C.
    • Ripoche, A.
    • Celette, F.
  • Source: Agricultural Water Management
  • Volume: 97
  • Issue: 11
  • Year: 2010
  • Summary: The introduction of cover crops in vineyards is being tested as it mitigates some undesirable environmental impacts of these cropping systems, such as surface runoff and soil erosion. In some cases, it could even reduce an excessive vegetative vigour of grapevine. However, most of time, wine growers are worried that severe competition for soil resources between the intercrop and grapevines could impair grape yield and quality. WaLIS (Water baLance for Intercropped Systems), a simple model simulating the water resource partitioning in such an association was designed to evaluate and optimize the water regime in intercropped systems. The model is presented and evaluated in this paper in three situations: the same grapevine cultivar (cv. Aranel) with either bare soil, or a temporary intercrop (barley) or a permanent intercrop (tall fescue). All three situations are located in the south of France. It is based on an existing model, designed to simulate the water regime of a bare soil vineyard, which was adapted to take into account the specific features of intercropped systems. Hence it includes a two-compartment representation of the soil particularly adapted to row crops. The simulation of a grass cover growth and its transpiration were added. Finally, particular importance was dedicated to the simulation of surface runoff which was the main source of the original model deviation during the winter period and made difficult multi-year simulations. Now, the model appears to be able to evaluate perennial cropping systems and provide decision support. The WaLIS model simulated the water available for both grapevine and intercrop well, and it proved to be efficient in most of the tested situations and years. The modelling of the water stress experienced by both crops was also generally good and all water fluxes simulated by the model were realistic. The main observed deviation in the simulation of the water soil content occurred during winter, i.e. outside the grapevine growth period. It was very likely due to the use of a constant parameter value for the surface runoff which did not take into account of changes in the soil surface and their effects on water infiltration. Finally, the analysis of sensitivity made on the WaLIS model showed that it is robust and sensitive to a few parameters, which drive the maximal grapevine transpiration and soil evaporation or are linked to the surface runoff simulation. The work also revealed how a good estimate of the total soil water available for each crop is crucial. This model, easy to use and parameterise, can provide sound management advice for designing valuable intercropped cropping systems.
  • Authors:
    • Zhang, J. P.
    • Sun, J. S.
    • Liu, Z. G.
    • Qiu, X. Q.
    • Duan, A. W.
    • Gao, Y.
    • Wang, H. Z.
  • Source: Agricultural Water Management
  • Volume: 98
  • Issue: 1
  • Year: 2010
  • Summary: In a field experiment in the Yellow River Basin conducted in 2007 and 2008, it was found that, under full irrigation, the roots of maize not only penetrated deeper than those of soybean but also extended into soybean stands underneath the space between inner rows of soybean. The roots of soybean, however, were confined mainly to the zone near the plants. Horizontal growth of the roots of both the crops was confined mainly to the soil layer 16-22 cm below the surface, a layer that lay above an existing plough pan. Root length density (RLD) was much higher in the top layer (0-30 cm deep) and in the zone closer to the plants. The exponential model proved suitable to describe the RLD vertically and horizontally in both sole cropping and in intercropping.
  • Authors:
    • Wang, H. Z.
    • Chen, J. P.
    • Zhang, J. P.
    • Qiu, X. Q.
    • Duan, A. W.
    • Gao, Y.
  • Source: Chinese Journal of Eco-Agriculture
  • Volume: 18
  • Issue: 5
  • Year: 2010
  • Summary: In this study, a radiation interception and utilization model was developed through an experiment on maize/soybean intercropping systems with different intercropping proportions of maize and soybean to assess crop growth and yield. In the model, crop biomass and yield are calculated as functions of photosynthetic active radiation ( PAR), radiation interception fraction ( F) and radiation use efficiency ( RUE). PAR is estimated from ratios of PAR to solar radiation (). F is calculated by using the Keating and Carberry equation. Time for emergence, flowering and maturity are determined by growing degree days ( GDD) since planting. Results indicate that the model accurately simulates total biomass and yield of fully irrigated maize/soybean intercropping system.
  • Authors:
    • Gaweda, D.
    • Harasim, E.
  • Source: Annales Umcs, Agricultura
  • Volume: 65
  • Issue: 1
  • Year: 2010
  • Summary: The objective of the study was to assess the effect of catch crops on the yield and energetic efficiency of the main cereal crop grown under monoculture. The study was carried out in the years 2006-2008 at Uhrusk experiment farm. The trial was localized on a mixed rendzina soil, of medium depth, developed from chalk limestone. The experiment included spring cereals such as wheat, barley and oats as well as stubble catch crops: non-catch crop control, white mustard, blue phacelia, winter oilseed rape and a legume mixture - narrow-leaved lupin+field peas. The highest yield increase over the non-catch crop control (9.4%) was found when phacelia was grown as a catch crop after wheat. The lowest yield increment occurred in barley grown after legumes (ca. 8%) and in oats gown after phacelia and oilseed rape (ca. 7%). The energetic efficiency of cereal production was more related to the main cereal crop than to the catch crop. The production of barley and oats had a higher energetic efficiency (4.71 and 4.65, respectively) than that of wheat (3.84). The use of catch crops lowered but to a small degree the energetic efficiency of spring cereal production.
  • Authors:
    • Thenua, O. V. S.
    • Sharma, U. C.
    • Abraham, T.
    • Shivakumar, B. G.
  • Source: The Indian Journal of Agricultural Sciences
  • Volume: 80
  • Issue: 5
  • Year: 2010
  • Summary: A field experiment was conducted during winter ( rabi) season of 2005-06 and 2006-07 in the Agronomy Research Farm of Amar Singh College, Lakhaoti, Uttar Pradesh to study the effect of levels of irrigation and fertility on chickpea ( Cicer arietinum L.) and mustard ( Brassica juncea L. czernj & coss.) in sole and intercropping systems. The experiment was conducted in split-plot design with 3 replications. The combination of treatments consisted of 3 cropping systems, namely sole mustard (C 1), sole chickpea (C 2) and chickpea+mustard intercropping (C 3) (4:1 raw ratio) and 4 irrigation levels [no irrigation (I 0), irrigation at pre-flowering (I 1), at pod formation (I 2) at both pre-flowering and pod formation (I 3)] for chickpea allotted to main plots and 3 fertility levels [F 1 (20:40:10 kg N, P 2O 5 and S/ha) F 2 (40:60:20 kg N, P 2O 5 and S/ha) and F 3 recommended dose of fertilisers (RDF)] for both the crops on row length basis to sub-plots. The sole Indian mustard recorded higher seed yield compared to intercropping. The yield reduction in mustard was to the tune of 58.9% and 60.0% in the first and second year, respectively, due to intercropping chickpea. Irrigation, on an average increased the mustard yield by 6.47% (I 1), 12.18% (I 2) and 13.18% (I 3) compared to no irrigation (I 0). Similarly fertilizer treatments F 2 and F 3 on an average increased mustard yield by 10.17% and 18.46%, respectively, over the F 1. The intercropping of chickpea and mustard in 4:1 raw ratio was significantly superior to sole crops of either chickpea or mustard in terms of yield and economics. Between the sole crops, chickpea was better as compared to mustard. Application of recommended dose of fertilizers (20:60:20 kg, N, P 2O 5 and S/ha) on area basis was superior.