• Authors:
    • Collins, H.
    • Moore, A.
    • Alva, A.
  • Source: Journal of Crop Improvement
  • Volume: 26
  • Issue: 2
  • Year: 2012
  • Summary: Potato ( Solanum tuberosum L.) tuber yield and quality are impacted by irrigation and nitrogen (N) management. This study was conducted in the Pacific Northwest (PNW) region of United States to evaluate the effects of deficit irrigation (DI) and rates of pre-plant and in-season N applications on Ranger Russet and Umatilla Russet cultivars. In 2004, with Ranger Russet only, DI with 20% lower total irrigation for the entire growing period resulted in 28% tuber yield reduction compared to that of plants irrigated to replenishment full evapotranspiration (ET), i.e., full irrigation (FI). A subsequent study in 2006 and 2007 with DI (14% to 17% deficit) resulted in tuber yield reduction of 7% to 10% in both cultivars compared to full ET irrigation. Yield reduction in DI was generally attributed to reduction in large weight tubers, >0.227 kg/tuber, in both cultivars across three years. Petiole NO 3-N concentrations were greater in plants grown under DI as compared to those of plants in full ET irrigation across all years and cultivars, particularly during tuber maturation stage. This is an important consideration as increased N availability during the late growing season adversely affects tuber quality. Petiole NO 3-N concentrations increased with increased in-season N rates. In 2007, 112 kg.ha -1 in-season N resulted in petiole NO 3-N concentrations below desirable concentrations across most of the growing season in both cultivars. This, in turn, contributed to a significant reduction in tuber yield as compared to the 224 kg.ha -1 in-season N rate. Continuous DI with 14% to 20% reduction in water as compared to irrigation to replenish full ET, begun three to four weeks after seedling emergence, had significant negative effects on tuber yields of both cultivars in high-production irrigated growing conditions. Application of N up to 112 kg ha -1 as pre-plant soil applied plus 224 kg ha -1 of in-season fertigation in five applications at two-week intervals beginning four weeks after seedling emergence appears to be adequate to support high yields of high-quality tubers.
  • Authors:
    • Moore, A.
    • Ren, H.
    • Alva, A.
  • Source: American Journal of Plant Sciences
  • Volume: 3
  • Issue: 1
  • Year: 2012
  • Summary: Biomass accumulation and partitioning into different plant parts is a dynamic process during the plant growing period, which is influenced by crop management and climate factors. Adequate knowledge of biomass partitioning is important to manage the crops to gain maximum partitioning of assimilates into plant parts of economic significance, i.e. tubers in potato. This study was conducted using two potato cultivars grown in a sandy soil with center pivot irrigation under full irrigation (FI; irrigation to replenish 100% of water loss by evapotranspiration [ET]) and deficit irrigation (DI; replenish only 80% ET) and two nitrogen(N) rates (pre-plant + in-seasonN rates of 56+112 or 168+336 kg/ha). Plant samples were taken on 22, 44, 66, and 98 days after seedling emergence (DAE). With high N rate, tuber biomass of 'Umatilla Russet' cultivar in relation to total plant biomass varied from 23%-88% and 25%-86% over 22 to 98 DAE for the FIand DI treatments, respectively. The corresponding partitioning ranges were 30%-93% and 38%-93% at the low N rate. With respect to the'Ranger Russet' cultivar, biomass partitioning to tubers ranged from 36%-82% and 23%-84% for the FIand DI, respectively, at the high N rate, and 29%-87% and 39%-95% at the low N rate. Overall, this study demonstrated that within the range of N rate and irrigation treatments the biomass portioning into tubers was largely similar in both cultivars.
  • Authors:
    • Wuthrich, R.
    • Hebeisen, T.
    • Ballmer, T.
    • Gut, F.
  • Source: AGRARFORSCHUNG SCHWEIZ
  • Volume: 19
  • Issue: 5
  • Year: 2012
  • Summary: From 2008 to 2010 Agroscope Reckenholz-Tanikon Research Station ART examined the effectiveness of drip irrigation with the potato varieties Agria and Charlotte. Irrigation hoses were laid out between the rows or in each ridge of the furrow with an identical water supply. Only in 2008 there was a tendency for the gross yields produced by the irrigated methods to be higher. In 2008 and 2009, the Agria variety produced 12 to 16 per cent higher marketable yields with the irrigated methods. The percentage yield of oversized tubers (>70 mm) was the lowest in all three years of the trial with ridge irrigation. With irrigation, Agria's yield share in ware size rose by 2 to 9 absolute per cent in all the years of the trial. With the Charlotte variety, no effects of irrigation were noted on the percentage of ware size tubers. In two of the three years, the irrigated tubers of both varieties displayed a higher starch content. Irrigated tubers showed a higher infestation rate with powdery scab, but a lower infestation rate with common scab in netted, deep pitted and raised form respectively than non-irrigated tubers. Drip irrigation is a water- and energy-saving method for future yield and quality assurance in potato production.
  • Authors:
    • Weatherhead, E.
    • Jones, R.
    • Keay, C.
    • Daccache, A.
    • Stalham, M.
    • Knox, J.
  • Source: Journal of Agricultural Science
  • Volume: 150
  • Issue: 2
  • Year: 2012
  • Summary: The viability of commercial potato production is influenced by spatial and temporal variability in soils and agroclimate, and the availability of water resources where supplementary irrigation is required. Soil characteristics and agroclimatic conditions greatly influence the cultivar choice, agronomic husbandry practices and the economics of production. Using the latest (UKCP09) scenarios of climate change for the UK, the present paper describes a methodology using pedo-climatic functions and a geographical information system (GIS) to model and map current and future land suitability for potato production in England and Wales. The outputs identify regions where rainfed production is likely to become limiting and where future irrigated production would be constrained due to shortages in water availability. The results suggest that by the 2050 s, the area of land that is currently well or moderately suited for rainfed production would decline by 88 and 74%, respectively, under the 'most likely' climate projections for the low emissions scenario and by 95 and 86%, respectively, for the high emissions scenario, owing to increased likelihood of dry conditions. In many areas, rainfed production would become increasingly risky. However, with supplementary irrigation, c. 0.85 of the total arable land in central and eastern England would remain suitable for production, although most of this is in catchments where water resources are already over-licensed and/or over-abstracted; the expansion of irrigated cropping is thus likely to be constrained by water availability. The increase in the volume of water required due to the switch from rainfed- to irrigated-potato cropping is likely to be much greater than the incremental increase in water demand solely on irrigated potatoes. The implications of climate change on the potato industry, the adaptation options and responses available, and the uncertainty associated with the land suitability projections, are discussed.
  • Authors:
    • Moreira, M. A.
    • Nunes, J. C. S.
    • Fontes, P. C. R.
  • Source: Bioscience Journal
  • Volume: 28
  • Issue: 3
  • Year: 2012
  • Summary: Two independent experiments were established in a Red Yellow Argisol Cambic soil objecting to evaluate potato yield and tuber size distribution profile in response to interplant spacing and fertilizer recommendation criteria. One experiment was sprinkler irrigated and the other one was drip-irrigated. Six treatments resulting from the combination of three interplant spacing (29, 36, and 50 cm) and two fertilizer recommendation criteria (by area or by plant number in the area) were evaluated in a completely randomized block design and five replications. In both experiments, marketable potato yield (tuber number and mass) exponentially decreased with the increase in row spacing and it was affected by recommendation criteria. The combination of fertilizer recommendation by area with narrower space optimizes marketable tuber yield by increasing medium and small tubers and also increases fertilizer use efficiency. Environmental, economic and practical implications of the results to potato production are discussed.
  • Authors:
    • Frisvold, G. B.
    • Konyar, K.
  • Source: Water Resources Research
  • Volume: 48
  • Issue: 5
  • Year: 2012
  • Summary: This study examined how agriculture in six southwestern states might adapt to large reductions in water supplies, using the U.S. Agricultural Resource Model (USARM), a multiregion, multicommodity agricultural sector model. In the simulation, irrigation water supplies were reduced 25% in five Southern Mountain (SM) states and by 5% in California. USARM results were compared to those from a "rationing" model, which assumes no input substitution or changes in water use intensity, relying on land fallowing as the only means of adapting to water scarcity. The rationing model also ignores changes in output prices. Results quantify the importance of economic adjustment mechanisms and changes in output prices. Under the rationing model, SM irrigators lose $65 in net income. Compared to this price exogenous, "land-fallowing only" response, allowing irrigators to change cropping patterns, practice deficit irrigation, and adjust use of other inputs reduced irrigator costs of water shortages to $22 million. Allowing irrigators to pass on price increases to purchasers reduced income losses further, to $15 million. Higher crop prices from reduced production imposed direct losses of $130 million on first purchasers of crops, which include livestock and dairy producers, and cotton gins. SM agriculture, as a whole, was resilient to the water supply shock, with production of high value specialty crops along the Lower Colorado River little affected. Particular crops were vulnerable however. Cotton production and net returns fell substantially, while reductions in water devoted to alfalfa accounted for 57% of regional water reduction.
  • Authors:
    • Hossain, S.
    • Miah, M. A. M.
    • Haque, M. A.
    • Rahman, M. M.
  • Source: Bangladesh Journal of Agricultural Research
  • Volume: 37
  • Issue: 1
  • Year: 2012
  • Summary: Potato is one of the important food crops in Bangladesh. Its demand is increasing day by day. The Tuber Crop Research Centre (TCRC) of BARI released 40 HYV potato varieties and disseminated them in the farmer's fields through different agencies. But most varieties were not adopted well by the farmers due to unknown reasons. Therefore, an attempt was made to assess the level of adoption and profitability of BARI released potato variety at farm level. Data were collected from 150 randomly selected potato farmers from Munshigonj, Bogra and Comilla districts during January-February 2010. The results indicated that 48% potato areas were covered by Diamant variety, 16% by Cardinal, 22% by Granola, and the rest 14% areas were covered by Binella, Asterix, Provento, Felsina, Multa and Hira. The cost of BARI released potato cultivation was Tk 2, 10,629 and Tk 1, 84,135 per hectare on full cost and variable cost basis. The major share of total cost was for seed (42%) followed by fertilizer (21%) and human labour (14%). The average yield of potato was 26 t/ha with gross margin of Tk 1, 51,003 per hectare. The net return of potato cultivation was Tk 1, 24,509 per hectare. The benefit cost ratios were 1.59 and 1.82 on full cost and variable cost basis. Human labour, land preparation, seed, and irrigation had positive and significant effect on potato production. Nonavailability of HYV seed at proper time, lack of technical knowledge, high price of seed and fertilizer, infestation of insect and diseases, and lack of storage facilities were the major problems of potato production.
  • Authors:
    • Fan, M. S.
    • Hao, Y. F.
    • Hu, B.
  • Source: China Vegetables
  • Issue: 10
  • Year: 2012
  • Summary: The effects of Chinese cabbage N application rate on Chinese cabbage yields, nitrogen utilization, nitrate contents, and nitrate nitrogen accumulation in soil were studied under potato-Chinese cabbage double cropping system in Hetao irrigated area of Inner Mongolia with 5 N application rates at Chinese cabbage planting season. The results showed that the yields and the double cropping net economic returns were the highest with the Chinese cabbage N application rate of 120 kg.hm -2; the double cropping system N accumulation and N recovery ratio were enhanced at the total N application rate from 225 kg.hm -2 to 405 kg.hm -2, compared with that of the conventional mono potato production in the open field at the N application rate of 225 kg.hm -2; the nitrate contents in Chinese cabbage and the nitrate accumulations within 0-160 cm soil profiles were increased with the increscent N applied rates. At the Chinese cabbage N application rate was ≥120 kg.hm -2, the nitrate contents in Chinese cabbage reached a high level, and the nitrate accumulations within 0-160 cm soil profiles were ≥162 kg.hm -2, hence the risk of nitrate contamination in underground water was increased for autumn irrigation. Reasonable N application rate had an effective effects on reducing nitrate contamination in groundwater, reducing nitrate content in Chinese cabbage, and increasing net economic return.
  • Authors:
    • Laurie, R. N.
    • Jaarsveld, P. J. van
    • Faber, M.
    • Laurie, S. M.
    • Plooy, C. P. du
    • Modisane, P. C.
  • Source: Scientia Horticulturae
  • Volume: 142
  • Year: 2012
  • Summary: beta-Carotene rich orange-fleshed sweet potatoes are increasingly used in community-based interventions aimed at addressing vitamin A deficiency, but are often cultivated in marginal soils and with sub-optimal agricultural inputs. The aim of the study was to determine (i) beta-carotene content, beta-carotene yield and water productivity at increments of water application, and, (ii) beta-carotene content and beta-carotene yield at increments of chemical fertilizer application for orange-fleshed sweet potato in separate field trials. beta-Carotene content at the low irrigation treatment was between 15 and 34% higher than at optimal irrigation treatment. Increased water application brought about a two-fold increase in beta-carotene yield per unit area. The best combination of beta-carotene yield and water productivity (g beta-carotene ha -1 mm -1 water applied) was achieved at the intermediate (60%) irrigation treatment. Calculations showed that 1 ha of orange-fleshed sweet potato produced at the intermediate water application at yield level of 24.6-28.4 t ha -1, can potentially provide 452-730 households (of six persons) with an adequate amount of vitamin A over a period of 180 days. beta-Carotene content was 14% higher for both intermediate (50%) and high (100%) fertilizer treatments, compared to the 0% fertilizer treatment. beta-Carotene yield increased two-fold at the intermediate and four-fold at the high fertilization treatment. This paper provides novel information on the effect of irrigation on beta-carotene yield, as well as beta-carotene water productivity in orange-fleshed sweet potato. Follow-up research on a range of varieties is suggested toward obtaining recommendations for broad application in vitamin A crop-based interventions to optimize the beta-carotene yield in orange-fleshed sweet potato.
  • Authors:
    • Jennings, K. M.
    • Meyers, S. L.
    • Monks, D. W.
  • Source: Weed Technology
  • Volume: 26
  • Issue: 3
  • Year: 2012
  • Summary: Studies were conducted in 2008 and 2009 to determine the effect of S-metolachlor rate and application time on sweetpotato cultivar injury and storage root shape under conditions of excessive moisture at the time of application. S-metolachlor at 1.1, 2.2, or 3.4 kg ai ha -1 was applied immediately after transplanting or 2 wk after transplanting (WATP) to 'Beauregard', 'Covington', 'DM02-180', 'Hatteras', and 'Murasaki-29' sweetpotato. One and three d after S-metolachlor application plots received 1.9 cm rainfall or irrigation. S-metolachlor applied immediately after transplanting resulted in increased sweetpotato stunting 4 and 12 WATP, decreased no. 1 and marketable sweetpotato yields, and decreased storage root length to width ratio compared with the nontreated check. Sweetpotato stunting, no. 1 and marketable yields, and storage root length to width ratio in treatments receiving S-metolachlor 2 WATP were similar to the nontreated check. In 2008, Covington and Hattaras stunting 12 WATP was greater at 2.2 and 3.4 kg ha -1 (11 to 16%) than 1.1 kg ha -1 (1 to 2%). In 2009, S-metolachlor at 3.4 kg ha -1 was more injurious 4 WATP than 2.2 kg ha -1 and 1.1 kg ha -1. While cultivar by treatment interactions did exist, injury, yield, and storage root length to width ratio trends were similar among all cultivars used in this study.