Impacts of Mono Crop Based Agriculture on Food Production: The increased use of fertilizers, pesticides and herbicides caused deterioration of our natural environment, particularly loss of many green, leafy vegetables that had been important sources of vitamin A, calcium and iron grew at the edge of paddy field or roadside naturally in rural Bangladesh. Moreover, these chemical agents are responsible for stiff decline in native fish production. Therefore, fish that was once available in paddy field, protein supplier to the poor farmer, now becomes nightmare. If consider the cost of fertilizers, pesticides, herbicides and environmental affects local varieties would be more profitable than hybrid. In 2004, farmers of Nayakrishi Andolon (new agricultural movement) cultivated 1,561 local varieties of rice by ecologically friendly farming systems and got higher return in production compared to High Yielding Varieties ( HYV). Hybrid varieties do not produce seed. So to continue production, farmers have to buy seed every year from some hybrid seed producing companies which they produced earlier in their field. In this way, the legal right of farmer over seed, which they practiced from ancient time, now rests with the companies; hence, the producer (farmer) is becoming consumer of some multinational companies like Aventis, Dupont, Monsanto, Syngenta.
Current Agriculture Practices in Bangladesh: Rice is the staple food of Bangladesh, accounting for 76% of the cultivated area, 78% of the irrigated area, 52% of agricultural GDP, and 71% of caloric intake (BBS, 2008). Regrettably, to increase production, many so-called high-yielding varieties have been introduced without testing and considering their impact on local ecosystems. With the pressure of such hybrid varieties most of our local varieties have already become extinct and many are endangered.
Traditional Agriculture Practices in Bangladesh: Traditionally, farmers are used to maintain a sequence in crop rotation. They grew pulses after rice. Leguminous pulses recover nutrients consumed by rice earlier. Thus, the land remains productive naturally without using any artificial fertiliser (leguminous pulses fix atmospheric nitrogen into soil and thus reduce the demand of nitrogen-based urea fertilisers). Moreover, they used cow-dung or compost that provides essential nutrients to the land without causing any damage to environment. These traditional farming systems also control pest and diseases biologically. Once, in the low-lying areas of Brahmaputra-Jamuna and Meghna floodplains, which cover middle and northern parts of Bangladesh, farmers would grow mustard abundantly after the Aus season. The mustard field is habitat for bees and bee is considered as the keystone species in pollination. Moreover, flowers of pulses and cereals attract many pollinating agents like birds, butterfly, moths and help to sustain productivity. In a report, Losey and Vaughan (2006) state that the value of bee pollination services in the US alone range up to $16 billion annually.
Government Initiatives in the Agriculture Sector: Political decisions regulate the agro-sector in Bangladesh. After independence, most of the governments took attempts to gain self-sufficiency in food production. However, their short-sighted planning or narrow political interests hastened the loss of biodiversity. Often, the political government declares ‘we are now self-sufficient’ or ‘our food security has been achieved’ and they make it a weapon to win the elections. In reality, they never reached the target.
Status of Agriculture Biodiversity in Bangladesh: Naturally, Bangladesh is endowed with high crop diversity. Until now, 10000 varieties of rice have been identified. Moreover, this area is also enriched with leguminous pulses (3,463 plant genetic resources of local origin from 8 species have been identified). Besides, this region is home to more than 80 fruit species with high number of PGR (including both domesticated and wild fruits). In case of vegetables, 39 species (11 species of tubers, 8 of leaves, and 20 of fruits) with more than 10,000 PGR again bear testimony to this region’s species richness (Banglapedia, 2004). Potentiality of Biodiversity Based Organic Agriculture in Bangladesh Despite pessimistic scenarios in the agro-sector of Bangladesh, have also some heartening examples. A farmer of Jhenaidah, Hraicharan Das, has introduced the high-yielding variety of indigenous paddy, locally known as hari dhan, through selection process. The farmers of Pairabandha of Mithapukur upazila in Rangpur use compost, crop residue, water hyacinths and other perishable items instead of chemical fertilisers and pesticide in their field. Some farmers of Kaunia are producing vermi-compost (contains high quantities of nitrogen, phosphorous and potassium) by cultivating earthworm at their home (Nazrul Islam, The Daily Star, 16th May, 2008). In a recent research Dasgupta et. al. (2008) showed that Integrated Pest Management (IPM) rice farming is more profitable than conventional mechanized rice farming.