Impact of Plant Density and Irrigation on Yield of Hemp (Cannabis sativa L.) in a Mediterranean Semi-arid Environment

Authors
1 Institute for Research and Training in Agriculture, Fisheries, Foods and Organic Production (IFAPA) Centro ‘Las Torres-Tomejil’ Ctra. Sevilla-Cazalla Km. 12,2. 41200. Alcalá del Río (Sevilla), Spain.
2 Phytoplant Research S. L., Rabanales 21 - The Science and Technology Park of Cordoba, Calle Astrónoma Cecilia Payne, Edificio Centauro módulo B-1. 14014. Córdoba, Spain.
Abstract
Within the context of climate change, water scarcity is the major constraint to the viability of many crops. Thus, it is necessary to develop strategies for sustainable water management, and introduce alternative crops to sustain the viability of agro-ecosystems. The main objective of this work was to assess the performance of hemp (Cannabis sativa L.) subjected to different plant densities and irrigation. Two cultivars (Carma and Ermes) were tested at three plant densities i.e. 40,000, 20,000, and 10,000 plants ha-1, under two irrigation regimes: i) fully irrigated with total water supply equal to 100% of ETc; and ii) deficit irrigation with 80% of ETc. The experimental design was a split-split plot with four replications per combination. At harvest, yield and its components (weight, plant height, stem diameter, and the weight of leaves and flowers relative to the stem weight) were evaluated. Also, the production of chemical compounds for medical use (terpenoids, and fatty acids Omega 3 and 6) were analyzed. The results showed that cv. Carma was the most appropriate in agricultural terms, with a yield significantly higher than cv. Ermes. In terms of plant density, 40,000 and 20,000 plants ha-1 gave the best results for yield, without significant impact by irrigation rates. Regarding the capability of these varieties to produce relevant chemicals, cv. Ermes yielded higher amounts than did cv. Carma. This work offers a preliminary assessment for hemp cultivation in Andalusia (SW Spain), with important potential under local agro-climatic conditions.

Keywords


1. Allen, R. G., Pereira, L. S., Raes, D. and Smith, M. 1998. Crop Evapotranspiration: Guidelines for Computing Crop Water Requirements. Irr. and Drain. Paper 56. UN-FAO, Rome, Italy.
2. Amaducci, S., Zatta, A., Pelatti, F. and Venturi, G. 2008. Influence of Agronomic Factors on Yield and Quality of Hemp (Cannabis sativa L.) Fibre and Implication for an Innovative Production System. Field Crop Res., 107: 161-169.
3. Amaducci, S., Pelatti, F., Medeghin-Bonatti, P. 2005. Fibre Development in Hemp (Cannabis sativa L.) as Affected by Agro-technique: Preliminary Results of a Microscopy Study. J. Ind. Hemp, 10: 31-48.
4. Amaducci, S., Errani, M. and Venturi, G. 2002. Response of Hemp to Plant Population and Nitrogen Fertilization. Ital. J. Agron., 6: 33-60.
5. Asgharipour, M. R., Rashed Mohasel, M. H. and Rafiei, M. 2006. The Effect of Plant Density and Nitrogen Fertilizer on Light Interception and Dry Matter Yield in Hemp (Cannabis sativa L.). Ir. J. Field Crops Res., 4: 230-217.
6. Cosentino, S. L., Testa, G., Scordia, D. and Copani, V. 2012. Sowing Time and Prediction of Flowering of Different Hemp (Cannabis sativa L.) Genotypes in Southern Europe. Ind. Crops Prod., 37: 20-33.
7. Casano, S., Grassi, G., Martini, V. and Michelozzi, M. 2010. Variations in Terpene Profile of Different Strains of Cannabis sativa L. Acta Hort., 925: 115-121
8. Deferne, J. L., and Pate, D. W. 1996. Hemp Seed Oil: A Source of Valuable Essential FattyAacids. J. Int. Hemp Assoc., 3: 4-7.
9. Dempsey, J. M. 1975. Hemp. University of Florida Press, Gainesvilles, FL, USA, PP: 46-89.
10. Doorenbos, J. and Pruitt, W. O. 1977. Guidelines for Predicting Crop Water Requirements. Irrig. and Drain. Paper No. 24.FAO, Rome,
11. AOAC International. 2000. Official Methods of Analysis of AOAC International. 17th Edition, Gaithersburg, Md.
12. Hackett, C. 1991. Mobilising environmental information about lesser known plants: the vale of two neglected levels of description. Agrofor. Syst., 14: 131-143.
13. Leizer, C., Ribnicky, D., Poulev, A., Dushenkov, S. and Raskin, I. 2000. The composition of hemp seed oil and its potential as an important source of nutrition. Journal of Nutraceuticals, Functional and Medical Foods 2: 35-53.
14. Lisson, S. and Mendham, N. 1998. Response of fiber hemp (Cannabis sativa L.) to varying irrigation regimes. J Int. Hemp Assoc., 5: 9-15.
15. Lisson, S. N. 1998. An integrated assessment of hemp (Cannabis sativa L.) and flax (Linum usitatissimum L.) as sources of fibre for newsprint production. Ph.D. University of Tasmania, 211 pp.
16. Mediavilla, V., Leupin, M. and Keller, A. 2001. Influence of the growth stage of industrial hemp on the yield formation in relation to certain fibre quality traits. Ind. Crops Prod., 13: 49-56.
17. Monteith, J.L. 1977. Climate and efficiency of crop production in Britain. Philosophical Trans. Royal Soc. London, 281: 277-294.
18. Rosenthal E. 1987. Marijuana Growers Handbook. Indoor/greenhouse edition. Quick American Publishing Company, San Francisco, USA.
19. Soil Survey Staff. 2006. Keys to Soil Taxonomy. 10th ed. USDA-Natural Resources Conservation Service, Washington DC, USA.
20. Struik, P. C., Amaducci, S., Bullard, M. J., Stutterheim, N. C., Venturi, G. and Cromarck, H. T. H. 2000. Agronomy of fibre hemp (Cannabis sativa L.). Ind. Crops Prod., 11: 107-118.
21. Tofani, C. 2006. Hemp harvesting and scutching. In: Design, Development and Up-scaling of a Sustainable Production System for HEMP Textiles: An Integrated Quality Systems Approach. Hemp-SYS Final Conference, Bologna, Italy, 27-28 April.
22. Van der Werf, H. M. G., 1994. Fiber Hemp in France. In: Rosenthal E (ed.) Hemp Today. Quick American Archives, San Francisco, USA, pp: 213-220
23. Van der Werf, H. M. G., Brower, K., Wijhuizen, M. and Withagen, J. M. C. 1995. The effect of temperature of leaf appearance and canopy establishment in fibre hemp (Cannabis sativa L.). Ann. Appl. Biol., 126: 551-561.