• Authors:
    • Askegaard, M.
    • Olesen, J. E.
    • Kristensen, K.
    • Rasmussen, I. A.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 142
  • Issue: 3-4
  • Year: 2011
  • Summary: Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ceramic suction cells and modelled drainage. There were significant effects on annual N leaching of location (coarse sand > loamy sand > sandy loam) and catch crops (without > with). Including a grass-clover green manure on 25% of the area did not increase N leaching compared with crop rotations without green manure. Also the application of animal manure did not influence N leaching, probably because even in the manured treatments the application rate was lower than crop demand. The results identify management of crop and soil during autumn as the main determinant of N leaching. Nitrate leaching was lowest for a catch crop soil cover during autumn and winter (avg. 20 kg N ha -1), a soil cover of weeds/volunteers had on avg. 30 kg N ha -1, and the largest N leaching losses were found after stubble cultivation (avg. 55 kg N ha -1). The N leaching losses increased with increasing number of autumn soil cultivations.
  • Authors:
    • Ortega-Farias, S.
    • Selles, G.
  • Source: ISHS Acta Horticulturae
  • Issue: 889
  • Year: 2011
  • Summary: These proceedings contain 79 papers on irrigation systems for horticultural crops. Specific topics covered include the following: improvement of water use for agriculture at catchment level under drought conditions; impact of climatic change on irrigated fruit tree production; effects of the irrigation regime and partial root zone drying on grape cv. Vermentino in Sardinia, Italy; effects of canopy exposure changes on plant water status in grape cv. Syrah; water use by drip-irrigated early-season peach trees; soil water content variations as water stress indicator in peach trees; reduction in the number of fruits in peach (T204) due to postharvest deficit irrigation; effects of irrigation management and N fertilizer on the yield and quality of apple cv. Gala; canopy temperature as an indicator of water status in citrus trees; effects of root anatomy on sap flow rate in avocado trees; influence of rootstock on the response of avocado cv. Hass to flooding stress; methods of selection for drought tolerance in potato; and drip irrigation for the establishment of strawberry transplants in southern California.
  • Authors:
    • Stepannikov, V.
    • Popova, E.
    • Popov, N.
  • Source: Mezhdunarodnyi Sel'skokhozyaistvennyi Zhurnal
  • Issue: 4
  • Year: 2011
  • Summary: Problems associated with the organization and provision of irrigation in the arid regions of Astrakhan Province, Russia, for the efficient use of both water and land are discussed. Recommendations are made for modernizing the structures of irrigated land use on the basis of scientifically based crop rotations. Economic evaluations of the main indicators of irrigated farming efficiency allowed farming systems to be developed for the Province's various natural and climatic zones and according to farm type (for example, meat or dairy farms, and farms devoted to growing cereals, rice, vegetables, cucurbit crops, fodder crops or potatoes).
  • Authors:
    • Vaseghi, E.
    • Bagheri, A.
    • Pour, A. S.
  • Source: Journal of Agricultural Economics Research
  • Volume: 3
  • Issue: 1
  • Year: 2011
  • Summary: In this study, three irrigation methods, namely, clouding tape, sprinkler and furrow in Rozveh Agricultural Research station (Fereidan Region in Isfahan) were evaluated. This study was conducted as randomized complete blocks design as a split-split strip plot layout with three replication during two years. Three irrigation systems were considered as main plots, two planting methods (one-row planting and two-row planting) as split subplots and two potato cultivars (Marfuna and Agria) as split-split subplots. Significant difference way observed between irrigation method treatments and planting method by analyzing two years results. Results of the 1st year showed the advantage of production mean in sprinkler and tape methods comparing to furrow method while the second year results showed the advantage of sprinkler method to tape method and tape method to furrow method. Comparison of yield mean of cultivars indicated that although Agria cultivar was preferred to Marfona cultivar in the 1st year, two year comparison of yield mean showed no significant difference between Agria and Marfuna cultivars with yield means of 24083 kg. and 23233 kg., respectively. The two year comparison results of yield means using different planting methods indicated that one row planting with mean yield of 24839 kg. was preferred significantly compare to two row planting with mean yield of 22927kg. One row planting showed significant preference in the 1st and 2nd year. Two year interaction effect of treatments showed that, except cultivar * year source, other interaction effects were not significant. Tape irrigation led to highest mean of WUE equal to 4.92 kg/m3. Economic evaluation of the project was carried out using benefit-cost ratio and present value of net benefits. The results indicated that sprinkler system was more beneficial. Tape and furrow methods for potato planting stood in the next place.
  • Authors:
    • Faridi, I. A.
    • Gillani, S. R.
    • Imran, M
    • Mahmood. Z.
    • Shaheen, Q.
  • Source: ASIAN JOURNAL OF CHEMISTRY
  • Volume: 23
  • Issue: 12
  • Year: 2011
  • Summary: This work evaluates the effects of water of irrigation in comparison with the source of water with special reference to chromium contamination in vegetables grown in various areas of Pakistan. Twenty samples of each vegetable, i.e., spinach ( Spinacia oleracea), lettuce ( Lactuca sativa), carrot ( Daucus cariota), capsicum ( Capsicum fistulosus), sweet pea ( Lathyrus odoratus), potato ( Solanum tuberosum) and cabbage ( Brassica oleracea), were collected during the year 2006 and replicated in 2007 and 2008. The range of concentration of chromium in vegetables irrigated with tube well water, canal water and municipal sewage water was in between 0.3-5.3, 1.01-13.09 and 1.11-29.89 ppm, respectively. Statistical analysis shows that the vegetables grown by tube well water and canal irrigation are quite safe and show less than 1% samples of vegetables showing chromium concentration more than that of permissible ambient levels. In case of vegetables irrigated by municipal sewage water more than 50% samples contained Cr more than that of permissible ambient levels. The results reflect that the uptake of chromium in vegetables is facilitated under the condition where the source of irrigation is sewage water.
  • Authors:
    • Pu, Y. L.
    • Xiao, H. L.
    • Wang, D.
    • Zhang, J. L.
    • Qin, S. H.
  • Source: Acta Agronomica Sinica
  • Volume: 37
  • Issue: 1
  • Year: 2011
  • Summary: Water supply scarcity is the main limiting factor for sustainable agriculture development in semiarid areas on the Western Loess Plateau. Because of imbalance for rainfall distribution, yield and water use efficiency (WUE) of potato, one of the dominant crops in middle Gansu province, are relatively low. To optimize supplemental irrigation system using limited catchment rainfall for rain-fed potato in the area, field experiments were carried out in 2008-2009 to determine evapotranspiration, WUE, yield, yield traits and quality of rain-fed potato under different supplemental irrigation amounts and timings. The results showed that WUE of potato increased significantly in the supplemental irrigation treatment of 45 mm, and decreased with increasing of irrigation amount. WUE and irrigating water use efficiency (IWUE) of potato were higher with supplemental irrigation at the seedling than the tuber expanding stage. WUE and IWUE were the highest under the 45 mm of irrigation at the seedling stage. Yield, rates of bigger tuber and middle tuber in rain-fed potato were increased, and small tuber rates were decreased by supplemental irrigation. Big tuber rates were increased by supplemental irrigation at the seedling stage, while medium tuber rates were increased by supplemental irrigation at the tuber expanding period. Potato numbers per plant were decreased, but tuber yield per plant was increased by supplemental irrigation. With increasing of irrigation amount, the yield of potato was not increased significantly, but green tuber rate and blet tuber rate were increased significantly. Starch content of potato was reduced, while protein content of tuber was increased by supplemental irrigation. Supplemental irrigation of 45 mm at seedling is optimal irrigation system for rain-fed potato in the area.
  • Authors:
    • Darbandi, M.
    • Asadi, S.
    • Hokmalipour, S.
    • Sharifi, R.
    • Barmaki, M.
    • Darabad, G.
  • Source: World Applied Sciences Journal
  • Volume: 15
  • Issue: 2
  • Year: 2011
  • Summary: In order to study the phenology and competition of potato and safflower, as compared to those of the pure cropping, a study was carried out using factorial experiment with completely randomized block design, with three replications. This study was done in experiment field of University of Mohaghegh Ardabili in 2010. The investigated treatments included potato pure cropping in the fixed density of 6 plants pre m 2, safflower pure cropping with the densities of 6, 12 and 18 plants per m 2 and the intercropping of potato (6 plants pre m 2 density) with safflower in the densities of 6, 12 and 18 plants per m 2. The analysis of variance in phenology stages of pure culture and mixed with potatoes showed that all treatments were significant differences. Comparison mean the stages of phenology of safflower intercropping with potatoes showed that two stage emergence and stem elongation earlier seen in plant grown intercropping 18 plant in per. Mixed safflower plants and potatoes compared to other treatments. Delay was seen the phenology stages of flowering and handle the product because the longer vegetative phase and later getting into the reproductive stage, in terms of lime. Safflower competition mean the stage phenology of safflower effected density of potato showed that pure cultures of safflower compared with intercropping earlier spend of emergence, the stem elongation and head visible, flowering and seed ripening. Coefficient of relative congestion in all treatments on potatoes is greater than one, this study shows advantage competitive potatoes compared to safflower. Similarly, the smaller of these indexes suggest weak competition in safflower as compared to potatoes. Amount of relative yield total of potatoes and safflower in all treatments intercropping was smaller than the one. It shows that both components mixed to compete for use limited recourses.
  • Authors:
    • Asadi, S.
    • Hokmalipour, S.
    • Sharifi, R.
    • Barmaki, M.
    • Kandi, M.
    • Darabad, G.
  • Source: Australian Journal of Basic and Applied Sciences
  • Volume: 5
  • Issue: 11
  • Year: 2011
  • Summary: In order to investigate the yield and yield components of mixed cropping of potato and safflower, as compared to those of the pure cropping, a study was carried out using factorial experiment with completely randomized block design and with three replications. This study was done in experiment field of University of Mohagheg Ardabili in the solar year 2010. The investigated treatments included potato pure cropping in the fixed density of 6 plants pre m 2, safflower pure cropping with the densities of 6, 12 and 18 plants per m 2, and the intercropping of potato (6 plants pre m 2 density) with safflower in the densities of 6,12 and 18 plants per m 2. The variance analysis of potato traits in both the intercropping and pure cropping indicated that, except from the number of stems pre m 2, other studied traits; including the number of tubes per plant, the tube weight per plant and the tube yield statistically differed meaningfully with each other. Moreover the results showed that all the studied traits including the number of receptacles pre plant, the number of seeds per receptacle, seed weight in the receptacle and seed yield, in terms of statistic figures differed with each other noticeably. In order to assess the efficiency of the intercropping, the indexes of LER and RVT were utilized. These indices proved that, almost in all cases, the intercropping is superior to the pure cropping. In this study the highest rates of LER and RVT (1/35 and 1/32 respectively), concerned the intercropping of safflower and potato with densities of 12 plants per m 2 and 6 plants per m 2 respectively.
  • Authors:
    • Li, Y.
    • Zu, Y.
    • Wu, B.
    • An, T.
    • Zhan, F.
    • Yang, J.
    • Fu, Z.
  • Source: Research of Environmental Sciences
  • Volume: 24
  • Issue: 11
  • Year: 2011
  • Summary: In order to explore the effects of different planting patterns for the effective control of farmland runoff contamination, loss of TN, TP, COD Cr and SS under different planting patterns were analyzed with field plot experiments. The results showed that the surface runoff, loss of TN, TP, COD Cr and SS under a mono-cropping system were higher than under a maize and vegetables intercropping system. The surface runoff, loss of TN, TP, COD Cr and SS could be reduced using a maize and vegetables intercropping system. The maize || cauliflower/potato intercropping pattern was the most effective. Comparing with cauliflower/potato mono-cropping system, its reduction percentages of surface runoff, TN, TP, COD Cr and SS were 79.59%, 86.87%, 84.23%, 91.41% and 82.46%, respectively.
  • Authors:
    • Halloran, J.
    • Larkin, R.
    • Olanya, O.
    • Honeycutt, C.
    • He, Z.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 9
  • Issue: 1
  • Year: 2011
  • Summary: Appropriate evaluation of soil phosphorus (P) availability is a prerequisite for best P management in potato production systems. Consequently, we evaluated soil test P and microbial biomass P in 10 rainfed and irrigated potato field soils which had a three-year crop rotation. Ammonium oxalate extracted P was the highest with a level of >1400 mg kg -1. Olsen P was moderate and ranged from 100 to 120 mg kg -1. Modified Morgan inorganic P (MMPi) was lowest (