Journal of Sustainable Agriculture ISSN: 1044-0046 (Print) 1540-7578 (Online) Journal homepage: http://www.tandfonline.com/loi/wjsa20 Increasing Productivity with Intercropping Systems in Cabbage Production Ismail Guvenc & Ertan Yildirim To cite this article: Ismail Guvenc & Ertan Yildirim (2006) Increasing Productivity with Intercropping Systems in Cabbage Production, Journal of Sustainable Agriculture, 28:4, 29-44, DOI: 10.1300/J064v28n04_04 To link to this article: http://dx.doi.org/10.1300/J064v28n04_04 Published online: 08 Oct 2008. Submit your article to this journal Article views: 151 View related articles Citing articles: 5 View citing articles Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=wjsa20 Download by: [University of California, Berkeley] Date: 06 November 2015, At: 13:02 Increasing Productivity with Intercropping Systems in Cabbage Production Ismail Guvenc Ertan Yildirim ABSTRACT. This study was carried out to determine the effect of dif- ferent intercropping systems on growth, mineral contents and yield of cabbage (Brassica oleracea L. var. capitata) under field conditions in 2000, 2001 and 2002. LER (Land Equivalent Ratio) and economic net income of different cropping systems based on cabbage as an index of intercropping efficiency were also evaluated. In the study, cabbage was used as a main crop, and cos lettuce (Lactuca sativa L. var. longifoila), leaf lettuce (Lactuca sativa L. var. crispa), radish (Raphanus sativus L.), onion (Allium cepa L.) and snap bean (Phaseolus vulgarism L. var. nanus) were used as intercrops. Each of the intercrops was planted in be- tween cabbage rows in separate plots. Cabbage and all intercrops were also grown as sole crops. There was no significant effect of different intercropping systems on growth characteristics and yield of cabbage compared with sole cabbage cropping except for radish as an intercrop, which affected adversely the yield and some growth characteristics of cabbage. Net income was increased significantly when cabbage was intercropped with cos lettuce, bean, leaf lettuce or onion. The values of Ismail Guvenc is affiliated with Department of Horticulture, Faculty of Agriculture, Atatürk University, Erzurum, Turkey (E-mail: [email protected]). Ertan Yildirim is affiliated with Ispir Hamza Polat Vocational Training School, Atatürk University, 25900, Ispir, Erzurum, Turkey (E-mail: [email protected]). Address correspondence to: Ertan Yildirim at the above address. The authors wish to thank Prof. Fahri Yavuz, Agricultural Economics Department, Downloaded by [University of California, Berkeley] at 13:02 06 November 2015 Atatürk University, for his assistance in the economic analysis of the study and to the anonymous reviewer(s) for valuable comments on the paper. The authors are very grateful to The Atatürk University, Scientific Research Projects Foundation, for their generous financial support (Project Number 2000/88). Journal of Sustainable Agriculture, Vol. 28(4) 2006 Available online at http://jsa.haworthpress.com © 2006 by The Haworth Press, Inc. All rights reserved. doi:10.1300/J064v28n04_04 29 30 JOURNAL OF SUSTAINABLE AGRICULTURE LER appeared to be greater than 1 under intercropping systems. Cropping systems did not significantly affect nitrogen, phosphorus, potassium, calcium, magnesium and iron content of cabbage. The results obtained in this study pointed out that intercropping systems based on cabbage might increase total yield, productivity and profitability. doi:10.1300/ J064v28n04_04 [Article copies available for a fee from The Haworth Document Delivery Service: 1-800- HAWORTH. E-mail address: <docdelivery@ haworthpress.com> Website: <http://www.HaworthPress.com> © 2006 by The Haworth Press, Inc. All rights reserved.] KEYWORDS. Cabbage, income, intercropping, land equivalent ratio (LER), yield INTRODUCTION Sustaining yield and income is a more important objective for farmers with limited resources than maximizing either yield or income. Addition- ally, the family objectives include maintaining food supply and income through the year, minimizing risk of failure in every season, keeping cash costs at a minimum, and meeting other social obligations in the com- munity (Fukai and Midmore, 1993). The improvement of agricultural sustainability favors the maintenance of the intercropping systems. In- tercropping is an efficient soil conservation practice due to the increased ground cover that it provides, as well as the exploitation of different soil layers due to the different depth of the root systems of the two species (Zimmermann, 1996; Jarenyama et al., 2000). Intercropping, through more effective use of water, nutrients and solar energy, can significantly enhance crop productivity compared with the growth of sole crops (Midmore, 1993). Many studies have indicated that intercropping with different vegetables was more productive and profitable than sole cropping because of the complementary effects of intercrops (Brown et al., 1985; Olasantan, 1991; Costa and Perera, 1998; Varghese, 2000; Baumann et al., Downloaded by [University of California, Berkeley] at 13:02 06 November 2015 2001; Yildirim and Guvenc, 2005). The majority of farmers in developing countries practice intercropp- ing. In developed countries, mechanization made intercropping inconve- nient, leading to its abandonment. However, recent studies indicate that intercropping may be compatible with mechanized agriculture and could provide an alternative to monocropping, especially for small, resource- poor farms (Itulya et al., 1997). Guvenc and Yildirim (1999) reported that intercropping is a safer and more stable system of agricultural pro- Research, Reviews, Practices, Policy and Technology 31 duction than sole cropping for small farms, where capital is limited and labor is available. Furthermore, intercropping has a great potential for pest and disease reduction (Theunissen, 1994, 1997; Theunissen and Schelling, 1996; Baumann et al., 2000). Studies have affirmed the util- ity of intercropping as one of the crop contingency strategies against any monocultured crop failure. Intercropping has been acclaimed inter- nationally as the most reliable approach to safeguard the sustainability of vegetable production (Coolman and Hoyt, 1993). Cabbage is grown widely in Turkey with a total annual production of 610,000 tons in 32,000 ha of area (Anonymous, 2003). According to a rat- ing system considering total yield per unit area, price per unit weight har- vested and the time required between seeding and harvest, cabbage is not a space-efficient crop and usually may not return a higher monetary value for the space occupied as compared with some vegetable crops (Splittstoesser, 1990). Cabbage is a relatively long-season crop and long-season crops in the first growth stage can be slow to grow and establish a full canopy, open- ing an opportunity for a short-season crop to be grown between rows (Fukai and Trenbath, 1993). Solar radiation, water and some nutrients that would be otherwise wasted during early growth stages of long-term crops can be utilized by an associated crop growing between the rows (Midmore, 1993). Although advantages of intercropping systems such as cabbage: bean (Gliessman and Altieri, 1982; Poniedzialek et al., 1989; Poniedzialek and Kunicki, 1995) and cabbage:broad bean (Vicia faba) (Sharma et al., 1988) have been demonstrated in earlier studies, there is no information on cabbage intercropping with cos lettuce, leaf lettuce and onion. To maintain yield and quality in intercropping systems, complementarities in patterns of resource use must be taken into account. Cultivars suitable for inter- cropping should enhance the complementary effects between species (Baumann et al., 2001). According to the latest available statistics, the vegetable production area in Turkey is 800,000 ha with a total production of 22 million tons with an average of 27 tons/ha approximately. In Northeast Turkey, suit- able areas for crop production are limited, and average productivity of Downloaded by [University of California, Berkeley] at 13:02 06 November 2015 vegetables is approximately 14-15 tons/ha, which is lower than the national average productivity of vegetable (Anonymous, 2003). The improvement of vegetable production through suitable intercrop com- binations has not yet been exploited to its full potential in Turkey. This study was aimed at optimizing cabbage production in mixture by choosing suitable intercrops and evaluating the sustainability of cab- bage intercropping systems on the basis of yield, LER and economic net income. 32 JOURNAL OF SUSTAINABLE AGRICULTURE MATERIALS AND METHODS This study was conducted under field conditions at Atatürk Univer- sity, Hamza Polat Vocational School, in Upper Coruh Valley (Ispir) in Turkey in 2000, 2001 and 2002. Ispir is located at 40° 29Ј N latitude 41° 01ЈE longitude, 1200 m above sea level. It had 136, 280 and 306 mm of a total rainfall and had 19.1°C, 19.3°C and 17.6°C of average air temper- ature in 2000, 2001 and 2002, respectively (April to September). Some soil physical and chemical properties of the experimental area are pre- sented in Table 1. Manure (30 t/ha) was applied to plots in previous Oc- tober for each experiment year. The manure used contained 1.1% N, Ϫ1 1.2% K2O, 1.6 P2O5, and EC of 6.2 dS m . Chemical fertilizer was used at the rate of 180 kg/ha N (as ammonium nitrate) and 100 kg/ha P2O5 (as triple super phosphate) and broadcast uniformly