Low External Input Supply Agriculture (LEISA)

Low-Input Agriculture

The term low-input agriculture has been defined as a production activity that uses synthetic fertilizers or pesticides below rates commonly recommended by the Extension Service. It does not mean elimination of these materials. Yields are maintained through greater emphasis on cultural practices, IPM, and utilization of on-farm resources and management.

The LEISA concept seeks to optimize the use of locally available resources by maximizing the complementary and synergistic effects of different components of the farming systems. External inputs are used in a complementary way.

Although, the term low-input fanning �.ds often been used to describe any system of alternative agriculture, if can be seen that it is distinctly different from organic farming etc. Nevertheless, any system that reduces purchased chemical inputs can be called low-input farming, some examples are:

1. Poultry litter can replace nitrogen fertilizers in the production of watermelons.
2. Legume cover crops can supply the total nitrogen requirements of pecan trees.
3. Compost amended potting mixes produce superior vegetable trarisplants than traditional soilless mixes.
4. No-till vegetable systems lire feasible using reduced herbicide rates to kill cover crops.
5. Subterranean clover living mulches supply nitrogen and weed control in peach orchards.

Integrated pest management is probably the oldest and most widely recognized Extension Service program devoted to low-input agriculture. However, only recently have the non-chemical approaches-such as cultural, mechanical, and biological-within the IPM framework been emphasized over the chemical component. Some programs, in fact, are now termed biologically- intensive IPM.

The intentions of the LEISA concept are obvious, but in practice the way it differs from integrated agriculture (understood to be a gradual minimization of external inputs) is not too clear. Defining what constitutes low inputs will always be difficult, therefore, LEISA remains an ambiguous concept.

Important characteristics of LEISA systems are that thy are based on a preventive approach whereby the problem is tackled at its roots, as opposed to the more symptom-curing nature of modern agriculture. Ecological and biological principles are the basis of the farm system. Nature works for the farmer, the farmer does not have to work against it. They are often based on local knowledge and production systems adapted to modern requirements and much less on external expertise. They are generally more labor-intensive compared to the mechanization-and petrochemical-intensive character of the agriculture envisioned by the Green Revolution and what it has become.

Criteria for LEISA
Ecological Criteria

1. Balanced use of nutrients and organic matter
2. Efficient use of water resources
3. Diversity of genetic resources
4. Efficient of genetic resources
5. Efficient use of energy sources
6. Minimal negative environmental effects
7. Minimal use of external inputs

Economic Criteria

1. Sustained farmer livelihood systems
2. Competitiveness
3. Efficient use of production factors
4. Low relative value of external inputs

Social Criteria

1. Wide-spread and equitable adoption potential, especially among small fanners
2. Reduced dependency on external institutions
3. Enhanced food security at the family and national level
4. Respecting and building on indigenous knowledge, beliefs and value systems
5. Contribution to employment generation