Eggplant Integrated Pest Management AN ECOLOGICAL GUIDE

___________________________________________________________________________________Major Agronomic Practicescompete with pathogens for nutrients and/or they produce certain substances that reduce pathogensurvival and growth. See section below.• Nitrogen regulator: compared to use of manure, compost prevents the loss of N through ammonia gas(NH 3) by fixing N into organic forms. However, some N is lost through NH 3when compost is turned.Compost reduces N below levels that cause burning of plants. Disadvantages of compost:• Large amount of organic matter required: the ideal amount of compost to apply to a field every year is20 tons/ha (about 2 kg/m 2 ). If a farmer wants to supply that amount of organic matter through onlycompost, a huge amount of organic matter is needed. It is very difficult to collect such amounts oforganic matter because in some cases, crop left-overs are also used to feed farm animals andmanure can be needed for cooking activities. Therefore, in most cases, it will be best to combine useof compost with other fertilization methods such as green manure and mulch.• Nutrient loss: Composting results in loss of nitrogen as ammonia gas (NH 3) when the compost isturned. Also, compost reduces nitrogen availability in comparison to the raw material from which itwas made.• Laborious: the process of making compost takes quite a bit of work as it involves collecting material,making the compost pile, turning the compost and carrying the compost to the field. Therefore it isrecommended that most organic matter be returned as mulch and other, unsuitable material be usedfor compost.• Compost is not as effective as raw organic matter in improving soil structure. As micro-organismswork to decompose raw organic matter, they excrete gels and slimes that bind soil particles togetherand enhance soil structure (modified from Peet, www1).How to prepare compostThere are many theories about the best way to prepare compost. Good thing to remember is: howeverthe compost is made, it will benefit the soil!The simplest method for composting is to pile up organic domestic and field waste material, finallycovering the pile with a layer of soil and possibly straw for insulation. Although many publications adviselayering of materials, the best way is to thoroughly mix plant materials throughout the pile. Use equalproportions of dry and wet material. Dry material such as straw, sawdust, and corn stalks contain littlewater and decompose slowly but they provide air to the pile. Make sure that woody material is choppedinto smaller pieces for quicker decomposition. Wet material such as fresh weeds, crop residue and freshmanure contain more water and decompose quicker than dry materials. Wet materials contain a lot ofnitrogen, and this is food (energy) for micro-organisms. A lot of food stimulates the micro-organisms to“start working” on decomposition quickly.A simple compost pile: organic waste piled on branches, covered with a layer of soil and strawSmall micro-organisms inside the pile will become active in breaking down the organic material. Theseorganisms also need water and air, so do not press the pile into a very compact pile of material! It isrecommended to build the pile on a layer of branches to provide air from underneath and to allowdrainage of the pile during rainfall.23Eggplant Ecological Guide