Yield performance and agronomic efficiency in oil pumpkins (Cucurbita pepo L. group Pepo) depending on production systems and varieties

Manfred Jakop 1 , Silva Grobelnik Mlakar 1 , Martina Bavec 1 , Martina Robačer 1 , Tjaša Vukmanič 1 , Urška Lisec 1  and Franci Bavec 1
  • 1 University of Maribor, Faculty of Agriculture and Life Sciences,, Pivola Hoče, Slovenia


In 2013 and 2014, a long-term trial (which was established in 2007) was conducted at the University Agricultural Centre in Pivola near Hoče. It included different production systems (conventional, integrated, organic, biodynamic), carried out in a field trial with oil pumpkins. The aim of the research was to analyse the effects of different production systems, varieties (hybrid and population variety) and years of production, on formation of oil pumpkin yields. The agricultural practice has been carried out in accordance with the applicable legislations and standards for the individual production system. When sowing, before fertilizing with nitrogen in early June and after the harvest, the amount of soil mineral nitrogen was monitored. We evaluated the number and weight of harvestable, unripe and decayed fruits, and yield of oil seed pumpkins and calculated the agronomic efficiency of the applied nutrients. The results showed that the year of production, the production system and the variety have a significant effect on some fruit characteristics and the yield of oil pumpkin seeds. The content of soil mineral nitrogen in May and September was significantly influenced by the production system and the year. In June, only the production system had a significant effect. The hybrid significantly increased the yields of oil pumpkin seeds in all production systems, even in the year that was less suitable for production. The agronomic efficiency of the applied nutrients in the biodynamic and organic production system is higher or equal than in the conventional production system, similarly, agronomic efficiency is higher in the hybrid compared to the oldest population variety efficiently. A comparable oil pumpkin yield can be expected in biodynamic and organic production, when proper nutrition and well carried out cultivation practices are combined with a new variety, when compared to less sustainable production systems, which often cause damage to the environment.

If the inline PDF is not rendering correctly, you can download the PDF file here.

  • 1. Bavec F. Navadna, oljna buča (Cucurbita pepo L. convar. citrullina (L.) Greb. var. styriaca Greb.) In: Nekatere zapostavljene in/ali nove poljščine. Fakulteta za kmetijstvo, Maribor, 2000.

  • 2. Bavec F, Bavec M. Organic production and use of alternative crops. CRC/Taylor & Francis, Boca Raton, New York, London 2007.

  • 3. Bavec M, Bavec F, Jakop M, Mlakar SG, Fekonja M. Productivity of sweet maize (Zea mays L. Saccharata) and nitrogen supply affected by cultivation systems in nontypical maize climate. Bulg. J. Agric. Sci. 2015;21:791-800.

  • 4. Bavec F, Jakop M. Pridelovanje buč golic. Kmetovalec. 1994;5:6-7.

  • 5. Bavec F, Jakop M, Grobelnik Mlakar S, Robačer M, Bavec M. Alternative field crops under different production systems, crop rotations as a basic principal for adaptation to climate changes and quality feed - food supply. Finale report CRP 2011-2014 V4-1137. University of Maribor, Faculty of Agriculture and Life Sciences. 2014;88.

  • 6. Bavec M, Mlakar SG, Rozman C, Pazek K, Bavec F. Sustainable agriculture based on integrated and organic guidelines: understanding terms-the case of Slovenian development and strategy. Outlook Agric. 2009;38:89-95.

  • 7. Becker K. Boehrnsen A. Effects of mechanical treatments on weed abundance and N-mineralization in the soil. Zeitschrift fur Pflanzenkrankheiten und Pflanzenschutz. Sonderheft,1994. http://agris.fao.org/agrissearch/search.do?recordID=DE94U0282 (15.6.2017).

  • 8. Berry PM, Sylvester-Bradley R, Philipps L, Hatch DJ, Cuttle SP, Rayns FW, Gosling P. Is the productivity of organic farms restricted by the supply of available nitrogen. Soil Use Manag. 2002;18:248-255.

  • 9. Chuan L, Hea P, Pampolinoc MF, Johnstond AM, Jin J, Xua X, Zhaoa S, Qiua S, Zhoua W. Establishing a scientific basis for fertilizer recommendations for wheat in China: Yield response and agronomic efficiency. Field Crop Res. 2013;140:1-8.

  • 10. Commission Regulation (EC) No. 889/2008 of 5 September 2008 laying down detailed rules for the implementation of Council Regulation (EC) No 834/2007 on organic production and labelling of organic products with regard to organic production, labelling and control. Official Journal of the European Union. 2008;L 250:1-84.

  • 11. Connor DJ. Organic agriculture cannot feed the world. Field Crops Res. 2008;106(2):187-190.

  • 12. Council Regulation (EC) No. 834/2007 of 28 June 2007 on organic production and labeling of organic products and repealing, Regulation (EEC) No. 2092/91. Official Journal of the European Union. 2007;L 189:1-23.

  • 13. De Neve S, Hofman G. Influence of soil compaction on alone explained a very large portion of the variance: C and N mineralization from soil organic matter and crop residues. Biol. Fertil. Soils 2000;30:544-549.

  • 14. de Ponti T, Rijk B, van Ittersum MK. The crop yield gap between organic and conventional agriculture. Agr. Syst. 2012;108:1-9.

  • 15. Deikea S, Palluttb B, Christena O. Investigations on the energy efficiency of organic and integrated farming with specific emphasis on pesticide use intensity. Eur. J. Agron. 2008;28(3):461-470.

  • 16. Demeter International e.V. 2012. Production Standards for the use of Demeter, Biodynamic and related trademarks. http://www.demeter.net/certification/standards/production (09.03.2013).

  • 17. FAO. World Reference Base for Soil Resources. ISSS-ISRIC-FAO, Rome. Report No. 103, 2006.

  • 18. Feller C, Bleiholder H, Buhr L, Hack H, Hess M, Klose R, Meier U, Stauss R, Boom T, Weber E. Phanologische Entwicklungsstadien von Gemusepflanzen: II. Fruchtgemuse und Hulsenfruchte. Pflanzenschutzd 1995;47: 217-232.

  • 19. Fixen P, Brentrup F, Bruulsema T, Garcia F, Norton R, Zingore S. Nutrient/Fertilizer Use Efficiency: Measurement, Current Situation and Trends. In: Drechsel P, Heffer P, Magen H, Mikkelsen R, Wichelns D (eds.), Managing Water and Fertilizer for Sustainable Agricultural Intensification. International Fertilizer Industry Association (IFA), International Water Management Institute (IWMI), International Plant Nutrition Institute (IPNI), and International Potash Institute (IPI). 1st edition, Paris, 2015.

  • 20. Goetzke B, Nitzko S, Spiller A. Consumption of organic and functional food. A matter of well-being and health. Appetite. 2014;77(1):96-105. Good AG, 21. Shrawat AK, Muench DG. Can less yield more? Is reducing nutrient input into the environment compatible with maintaining crop production? Trends Plant Sci. 2004;9(12):597-605.

  • 22. Ivančič A. Osnove rastlinske hibritizacije. Maribor, Fakulteta za kmetijstvo 2002; 88-122.

  • 23. Jakop M. The effects of cover crops, cultivation system and location on soil mineral nitrogen, growth and yield organically produced oil pumpkins (Cucurbita pepo L. convar. citrullina (L.) Greb. var. styriaca Greb.) [M. Sc. Thesis]. Maribor: Faculty of Agriculture and Life Sciences, University of Maribor 2010.

  • 24. Jariene E, Danilcenko H, Kulaitiene J, Gajewski M. Effect of fertilizers on oil pumpkin seeds crude fat, fibre and protein quantity. Agron. Res. 2007;5(1):43-49.

  • 25. Kocjan Ačko D. Buča. In: Poljščine. Založba Kmečki glas, Ljubljana 2015:105-110.

  • 26. Ma QH, Wang X, Li HB, Li HG, Zhang FS, Rengel Z, Shen JB. Comparing localized application of different N fertilizer species on maize grain yield and agronomic N-use efficiency on a calcareous soil. Field. Crop. Res. 2015;180:72-79.

  • 27. Martini E, Buyer JS, Bryant DC, Hartz TK, Denison RF. Yield increases during the organic transition: improving soil quality or increasing experience? Field Crops Res. 2004;86:255-266.

  • 28. Meier MS, Stoessel F, Jungbluth N, Juraske R, Schader C, Stolze M. Environmental impacts of organic and conventional agricultural products - Are the differences captured by life cycle assessment? J. Environ. Manag. 2015;149:193-208.

  • 29. Ministry of Agriculture, Forestry and Food RS (MKGP). 2006. Pravilnik o ekološki pridelavi in predelavi kmetijskih pridelkov oziroma živil. http://www.uradni-list.si/1/objava.jsp?urlid=2006128&stevilka=5415 (09.08.2017).

  • 30. Ministry of Agriculture, Forestry and Food RS (MKGP). 2008. Zakon o kmetijstvu. https://www.uradni-list.si/glasilo-uradni-list-rs/vsebina?urlid=200845&stevilka=1978 (04.09.2017).

  • 31. Ministry of Agriculture, Forestry and Food RS (MKGP). 2010. Pravilnik o integrirani pridelavi poljščin. https://www.uradni-list.si/glasilo-uradni-listrs/vsebina/101725#!/Pravilnik-o-integrirani-pridelavipoljscin (09.08.2017).

  • 32. Ministry of Agriculture, Forestry and Food RS (MKGP). 2012a. Zakon o kmetijstvu. https://www.uradni-list.si/glasilo-uradni-list-rs/vsebina/109499 (04.09.2017).

  • 33. Ministry of Agriculture, Forestry and Food RS (MKGP). 2012b. Zakon o kmetijstvu. https://www.uradni-list.si/glasilo-uradni-list-rs/vsebina/2012-01-3528?sop=2012-01 3528 (04.09.2017).

  • 34. Ministry of Agriculture, Forestry and Food RS (MKGP). 2013. Tehnološka navodila za integrirano pridelavo poljščin http://www.mkgp.gov.si/fileadmin/mkgp.gov.si/pageuploads/podrocja/Kmetijstvo/Integrirana_pridelava/TN_poljscine_2013.pdf (09.08.2017).

  • 35. Ministry of Agriculture, Forestry and Food RS (MKGP). 2014a. Zakon o kmetijstvu. https://www.uradni-list.si/glasilo-uradni-list-rs/vsebina/2014-01-1069?sop=2014-01-1069 (04.09.2017).

  • 36. Ministry of Agriculture, Forestry and Food RS (MKGP). 2014b. Tehnološka navodila za integrirano pridelavo poljščin. http://www.mkgp.gov.si/fileadmin/mkgp.gov.si/pageuploads/podrocja/Kmetijstvo/Integrirana_pridelava/TN_poljscine_2014.pdf (09.08.2017).

  • 37. Ministry of Agriculture, Forestry and Food RS (MKGP). 2014c. http://www.mkgp.gov.si/si/delovna_podrocja/kmetijstvo/integrirana_pridelava/tehnoloska_navodila/ (09.08.2017).

  • 38. Muller A, Ferre M, Engel S, Gattinger, Holzkamperf A, Huberg R, Mullerh M, Six J. Nemecek T, Dubois D, Huguenin- Elie O, Gaillard G. Life cycle assessment of Swiss farming systems: I. Integrated and organic farming. Agric. Syst. 2011;104:217-232.

  • 39. Muller A, Ferre M, Engel S, Gattinger A, Holzkamper A, Huber R, Muller M, Sixi J. Can soil-less crop production be a sustainable option for soil conservation and future agriculture? Land Use Policy 2017;69:102-105.

  • 40. National Meteorological Service (ARSO). 2017. RS Ministrstvo za okolje in prostor. http://www.arso.gov.si/o%20agenciji/knji%c5%benica/mese%c4%8dni%20bilten/ (04.08.2017).

  • 41. Nemecek T, Dubois D, Huguenin-Elie O, Gaillard G. Life cycle assessment of Swiss farming systems: I. Integrated and organic farming. Agric. Syst. 2011a;104(3):217-232.

  • 42. Pfiffner L, Mader P. Effects of biodynamic, organic and conventional production systems on earthworm populations. Biol. Agric. Hortic. 1997;15:3-10.

  • 43. Pingali PL. Green Revolution: Impacts, limits, and the path ahead. P. Natl. Acad. Sci. USA. 2012;109(31):12302-81230.

  • 44. Ren T, Li H, Lu J, Bu R, Li X, Cong R, Lu M. Crop rotation- dependent yield responses to fertilization in winter oilseed rape (Brassica napus L.). Crop J. 2015;3(5):396-404.

  • 45. Rochester IJ, Constable GA. Improvements in nutrient uptake and nutrient use-efficiency in cotton cultivars released between 1973 and 2006. Field Crop. Res. 2015;173:14-21.

  • 46. Scharp HC, Wehrmann J. Die Bedeutung des Mineralstickstoffvorrates des Bodens zu Vegetationsbeginn fur die N-Dungung zu Winterweizen. Landwirtschaftliche Forschung 1975;32:100-114.

  • 47. Seufert V, Ramankutty N, Foley JA. Comparing the yields of organic and conventional agriculture. Nature 2012;485:229-232.

  • 48. Shah A, Askegaard M, Rasmussen IA, Cordoba J, Eva M, Olesen JE. Productivity of organic and conventional arable cropping systems in long-term experiments in Denmark. Eur. J. Agron. 2017;90:12-22.

  • 49. Silgram M, Shepherd M. The effects of cultivation on soil nitrogen mineralization. Adv. Agron. 1999;65:267-311.

  • 50. Smith P, Haberl H, Popp A, Erb KH, Lauk C, Harper R, Tubiello F, de Siqueira Pinto A, Jafari M, Sohi S, Masera O, Bottcher H, Berndes G, Bustamante M, Ahammad H, Clark H, Dong HM, Elsiddig EA, Mbow C, Ravindranath NH, Rice CW, Robledo Abad C, Romanovskaya A, Sperling F, Herrero M, House JI, Rose S. How much land based greenhouse gas mitigation can be achieved without compromising food security and environmental goals? Glob. Change Biol. 2013;19:2285-2302. Specht K, Siebert R, Hartmann

  • 51. I, Freisinger UB, Sawicka M, Werner A, Thomaier S, Henckel D, Walk H, Dierich A. Urban agriculture of the future: an overview of sustainability aspects of food production in and on buildings. Agric. Hum. Values 2014;31:33-51.

  • 52. Statgraphics (Release Centurion XV) StatPoint, Inc., 2005.

  • 53. Statistical Office of the Republic of Slovenia (SURS). 2017. SI-STAT Data Portal - Environment and natural resources. Available at: http://pxweb.stat.si/pxweb/Dialog/varval.asp?ma=1502402E&ti=&path=../Database/Environment/15_agriculture_fishing/04_crop_production/01_15024_crops_area/&lang=1/ (8.9.2017).

  • 54. Štraus S. Potential indicators for sustainability assessment of food production on the field level [dissertation]. Maribor: Faculty of Agriculture and Life Sciences, University of Maribor, 2012.

  • 55. Touliatos D, Dodd IC, McAinsh M. Vertical farming increases lettuce yield per unit area compared to conventional horizontal hydroponics. Food Energy Secur. 2016;5(3):184-191.

  • 56. Turinek M. Comparability of the Biodynamic Production System Regarding Agronomic, Environmental and Quality Parameters [dissertation]. Maribor: Faculty of Agriculture and Life Sciences, University of Maribor, 2011.

  • 57. United States Department of Agriculture (USDA). 2017. Conservation Service Soils Textural Classification System. https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/?cid=nrcs142p2_054167 (14.8.2017).

  • 58. Vukmanič T. Ecological footprint of field crops and vegetables depending on production system [M. Thesis]. Maribor: Faculty of Agriculture and Life Sciences, University of Maribor, 2016.

  • 59. Wall DH, Nielsen UN, Six J. Soil biodiversity and human health. Nature 2015; 528: 69-76.

  • 60. Wien HC. The Cucurbits: Cucumer, Melon, Squash and Pumpkin. In: The Physiology of Vegetable Crops. CAB International, Wallingford,1997.

  • 61. Williams PRD, Hammitt JK. Perceived risks of conventional and organic produce. Pesticides, pathogens, and natural toxins. Risk Anal. 2001;21(2): 319-330.

  • 62. Xu XP, Liu XY, He P, Johnston AM, Zhao SC, Qiu SJ, Zhou W. Yield gap, indigenous nutrient supply and nutrient use efficient for maize in China. PLoS One 2015:10:1-12.

  • 63. Zhou W. Establishing a scientific basis for fertilizer recommendations for wheat in China: Yield response and agronomic efficiency. Field Crops Res. 2013;140:1-8.


Journal + Issues