«JM Thamaga-Chitja March 2008 Submitted in fulfilment of the requirements for degree: Doctor of Philosophy (Food Security), African Centre for Food ...»
Many studies have reported initial decreased yields during the first few seasons when switching from conventional agriculture to organic production. Mäder et al’s 2002’s report on a 21 year study on agronomic and ecological performance of biodynamic, bioorganic, and conventional farming systems in central Europe indicated that crop yields decreased by 20% in organic systems. On the other hand, Mäder et al (2002) also found that fertilizer and energy input was reduced by 34% to 53% and pesticide input by 97% in organic systems. It is a well established fact that, unlike commercial fertilizers, nutrients in organic sources are not readily available (Magdoff & van Es, 2000). The key to maintaining soil fertility in an organic farming system lies in the increased efficiency of nutrient flow from fixed to soluble states. Soil fertility management is one of the key principles of organic farming to maintain desired yields (Gaskell et al, 2007).
The role of organic matter in general soil health is critical (Magdoff & van Es, 2000).
High levels of organic matter are associated with reduced soil erosion and better water 15 infiltration, movement, retention and nutrient cycling (Stine & Weil, 2002; Mäder et al (2002). Organic sources of soil nutrients contribute more to soil organic matter than commercial fertilisers. Soil organic matter can be improved by crop rotation, tillage systems and manure application rates, even in conventional systems, but these practices are integral to organic farming. Crop yields are further influenced by the effects of treatments, such as mulching, that improve nitrogen levels, water retention and temperature stabilisation (Stine & Weil, 2002). It should be noted that the source of organic matter is important in determining its usefulness as a source of nitrogen.
Stine & Weil (2002) have shown that soil carbon plays a vital role in soil functioning and plant productivity in tropical climate zones when it comes to predicting how organic farming will perform. Organic farmers need to retain nitrogen and soil organic matter at the highest levels possible to ensure maximum soil productivity (Altieri, 1989). The volume or quantity of organic soil matter is also correlated with soil productivity and erosion control, both important considerations in terms of farm system sustainability (Gaskell et al, 2007). Increasing soil organic matter is a key aspect of organic production (Gaskell et al, 2007). Application of organic fertilisers such as animal manure or compost is essential to complement the primary sources of nitrogen, often fixed by legumes (Gaskell et al, 2007). Therefore, the choice of agroecological zones is important in achieving productive soils, yet smallholder farmers do not normally have an opportunity to select ideal locations and thus have to make the most of marginal land.
Clearly, organic matter is important for agricultural production and soil fertility, contributing to both soil quality and health (Quiroga et al, 2006; Magdoff & van Es, 2000). For farmers who are accustomed to the widespread use of agrochemicals, total elimination of these chemicals may be challenging. Conversion to organic agriculture requires new production and crop management systems. A survey commissioned by the United Kingdom’s Department for International Development (DfID) in 1996 showed that there is little evidence of knowledge and adoption of improved soil fertility management and crop protection of a non-chemical nature among smallholder farmers in sub-Saharan Africa who are accustomed to the application of chemicals (Harris et al, 1998). There may be value in reviving age-old, yet declining, indigenous African farming systems that may benefit organic farming today.
16 Crop diversification plays an important role in the stability of the organic farming system, unlike common mono-cropping practised in conventional farming. Organic farming promotes the planting of more plant species and an abundance of organism groups (Hole et al, 2005). Admittedly, many integrated farming systems used in conventional farming systems do incorporate biodiversity principles but still permit the use of agrochemicals.
The volume and type of crops grown organically vary worldwide, with vegetables being the most widely grown crops (Greene & Kreemen, 2001). Many South African smallholder farmers produce crops mainly for subsistence and traditionally plant crops they consume (Aliber, 2006). Organic farmers including African farmers need to increase farm diversity by producing a variety of vegetables, in addition to traditional root, legume and cucurbit crops, to break plant disease and pest cycles (Niggli et al, 2007). However, effective management is required to achieve different nutritional needs that the introduction of new crops may pose. Unlike commercial fertilisers, organic nutritional sources provide varied nutrient levels, based on the source and uncertain timing of release of nutrients (Magdoff & van Es, 2000). The stability of the organic production system is based on below- and above-ground biodiversity (Niggli et al, 2007).
In addition to the high transaction costs discussed earlier, the elimination of agrochemicals creates higher production risks for organic farmers. Organic farming is more vulnerable to adverse weather conditions and infestation by pests and uncertain and varied nutrient supply, which may reduce yields during the conversion to organic farming.
The organic farming system relies on prevention rather than cure based on crop rotations, resistant crop varieties, maintaining biodiversity and optimum crop health (Soil Association, 2007). Even in the strict and regulated certified organic industry a few pesticides are permitted where no other option exists (Soil Association, 2007).
For example, unusual whether patterns may lead to an outbreak of certain diseases and pests, bringing about an imbalance in the biodiversity. The Soil Association allows for such pesticides of simple (sulphur, soft soap, copper and rotenone) 17 chemical form compared to the complex chemicals used on conventional farms to be used in their certified organic farms in the United Kingdom (Soil Association, 2007).
The use of licensed biological control agents is also common and permitted in certified organic farming for the control of disease and pest control (Soil Association, 2007). The concept of biological control has been practiced for a long time even before it could be defined (Yobo, 2005). By definition, biological control in relation to disease control, refers to a mass introduction of one or more antagonistic organism, where the antagonists are referred to as biological control agents (BCA) (Yobo, 2005). These antagonists can be predators or parasites of pests which are released into the crop and have proved to be effective especially in greenhouse/glasshouse production (e.g Bacillus thuringensis Bt.).
Biological technology has indeed gained international success in recent years and has been used in organic farming to enhance plant growth and control pest and diseases is also known as Effective Microorganism (EM) use. EM is a complex combination of naturally occurring microorganisms (yeasts, photosynthesis bacteria, lactic acid bacteria and fungi) that function in certain combinations for effectiveness (Chamberlain & Daly, 2005). Through completive exclusion, EM with compete and displace some of the disease causing pathogens (e.g “damping off disease”).
A wide range of bacterial and fungal species has been investigated for the control of soil-borne plant pathogens. Nevertheless, there is still a large scope of investigation for potential BCA’s. There are several common biological control agents (BCA’s) for both vegetable and fruit crops which has been used with success. The following list provides a brief list organisms used as biological control agents for some common
• Aeromonas caviae (BCA for R.solani, S rolfsii, Fusarium oxysporum f.s.p ciceris in beans) Inbar & Chet (1991).
• T.viridae G, T. hamatum, T.harzianum (BCA for R. solano in cabbage) Lewis & Lumsden (2001).
• T.hamatum, Pseudomonus fluorescens, G virens (BCA for Fusarium spp in tomato) Larkin & Fravel (1998).
Application methods of BCA range from application to seed as a treatment in beans, incorporation into the growth medium in cabbage, drenching or incorporation into the growth medium in tomato and spraying or injection into fruit wounds in postharvest disease control in citrus.
Not all BCA’s are available in South Africa. Many BCA’s are foreign products and not registered as local commercial South African products. Such products would out of reach for most smallholders farmers in South Africa. In cases where such products become available, the financially lacking smallholder farmers will not be able to access them.
2.5 Processes involved in organic certification
Organic products are positioned as special products occupying a niche market place.
Understating the certification process is important for producers who may wish to trade in organic products to assist their decision making with regards to choosing to trade in organic products or remain conventional.
Unlike conventional commercial farming, marketing of organic produce requires certification of production processes and products by an authorised certification body (OFRF, 2001). The process of certification is lengthy, technical and costly. This may discourage smallholder farmers from entering certified organic farming. Organic certification is the process of determining compliance with standard organic agricultural practice (BDOCA, 2006). There are four reasons why farmers must be certified to market organic produce. First, certification distinguishes between organically-produced products and conventional products. Second, certification informs consumers of the production methods used, especially where consumer premiums exist for organic products. Third, certification protects farmers who adhere 19 to the standards against competition from those who do not follow organic practices.
Fourth, certification is a requirement to access high-value niche markets, both locally and abroad.
The process of certification used by BDOCA (one of the certification bodies in South Africa) is outlined in Table 2.2. The process of organic certification begins with the farmer contacting an authorised local certification body. If the farmer’s objective is to export to certain markets, the certification body of choice must be recognised and authorised by the importer, as differences in standards exist among countries (Barrett et al, 2002).
Table 2.2: Steps to be followed in organic farm certification (BDOCA, 2006)
Once certified, trained internal monitors and a quality control officer carry out an inspection. The inspection involves the use of a questionnaire to assess the state of
Organic certification standards are generally set by international bodies, such as the International Federation of Organic Agriculture Movements (IFOAM), and are adopted by local certifiers (Hellin & Higman, 2002). There are advantages and disadvantages to using local and international standards (Table 2.3).
Table 2.3: Advantages and disadvantages of local certification programmes Advantages of local organic certification Disadvantages of local organic certification
(Barret et al, 2002, pg. 307) Local certification programmes are of greater benefit to farmers as they are more sensitive to local conditions and culture. Local certification bodies are often cheaper and allow for better information flow between the certification body and farmers during the certification process. Even when local certification programmes conform to required international standards, farmers may experience difficulty in attaining and maintaining these production standards (Barret et al, 2002).
Banados & Garcia (2001) have shown that certification standards and legislation from key organic markets, such as those in the European Union, impact negatively on the ability of developing country farmers to trade internationally. For example,
Developing world farmers who want to export to the European Union have two options, as set out in Article 11 of Regulation 2092/91 of the United Kingdom legislation for organic farming. First, the organic farmer’s country is required to be listed as having standards equivalent to those of the European Union, as set out under Article 11(1). Currently, most listed countries belong to the developed world.
Second, developing countries, with non-equivalent standards, can apply for special permits and import authorisation (Article 11(6)) from the respective European Union control authorities (Barret et al, 2002), provided that production systems and inspection standards comply with those stipulated by the European Union (Banados & Garcia, 2001). South Africa does not currently have uniform national certification standards. Unless South Africa and other African countries wishing to benefit from international organic export opportunities formalise and standardise certification procedures, farmers in these countries cannot access or take advantage of international export opportunities.
The complexity of the certification process is increased by the required annual inspections and a rigorous internal monitoring system. Both processes demand capacity development among farmers and/or communities to gain and retain organic certification. Farmers in developing countries face obstacles such as high certification costs and inadequate knowledge of local conditions by foreign certifiers (Barret et al, 2002). To export organic produce, developing countries must pay for international inspection costs, which can be very expensive (e.g R 16 000-R 20 000). Local inspection bodies can be accredited by international certifiers, helping to lower the certification and monitoring costs. Small farmers can also group themselves into cooperatives or producer groups for group certification to further lower certification costs (Barret et al, 2002). However, internal monitoring systems in group certification must function well. This includes ensuring that a random sample of at 22 least 10% – 20% of the group’s farms are inspected annually by the certification body (Barret et al, 2002).