Cheaper availability of agricultural inputs

It was a matter of satisfaction to note the hon'ble Minister for Agriculture observe that the soil fertility in the country had declined to a dangerous level partly because of imbalanced application of chemical fertilisers. This is true that our farmers, due to lack of knowledge stress on application of too heavy doses of subsidised urea greatly harming the mutrient balance in soil and another reason may be that the availability of non-urea fertilisers is not at par with urea fertiliser. Under constant cultivation our soils are loosing organic matter faster than it can be replaced. A decrease in soil organic matter results in compact soils. Shallow roots are developed in draught and cloudy soils. Soil organic matter can be replenished by liberal use of farm yard manure (FYM), cow-dung, poultry manure and compost etc.

No investment is so far required in adding organic waste to the soil, only careful collection and maintenance of it would serve the purpose. But it has been brought to light that use of cow-dung in northern area of the country as fertiliser is decreasing causing fall in the crops production. People in this area have been using cow-dung as fuel due to shortage of fire wood and fuel crisis prevailing in the villages. This is really a very alarming situation and a time will come when every part of our country will face a serious crisis of shortage of cow-dung for direct application as organic fertiliser needed for crop productivity.

This is very true that not only cow-dung but any type of manure helps increase fertility status of soils due to its use at a large scale. Now-a-days the farmers are depending on the use of chemical fertilisers when it is widely felt that the indiscriminate use of agro-chemicals deplete the fertility status of soils and thereby production of crops is affected.

Emphasis should be given on the importance of other manures such as green manures, poultry droppings and huge amount of organic wastes regarded as by-products from mills and factories. If these wastes are properly managed and handled these can be used as organic fertilisers for increasing productivity of the crops and enhancing the strength of soils. The farmers be acquainted with the knowledge of management of soil and water to go for modern cultivation by adopting scientific methods with the announcement by the government to supply important agricultural inputs at cheaper rate required for this purpose. It may be mentioned here that Prime Minister Begum Zia also spoke on several occasions regarding qualitative changes to be brought in crop production, management and motivational programmes to induce the farmers to go for modern cultivation.

It must be remembered that soil management is only possible through the application of organic matters which after decomposition are converted into compost regarded as storehouse of plant nutrients. There are various reasons for the low production of food in our country and if the production has to be augmented then due attention should be paid on the availability of agricultural inputs. These include fertilisers, pesticides, qualitative seeds, irrigation and transfer of modern technology (from home and abroad) for the farmers.

Irrigation water must be tested before application to soil as it may contain high amount of heavy metals such as As, Cd, Cr, Hg, etc. which affect the growth and yield of the crop and at the same time the food becomes poisonous. Increased use of bio-fertilisers should be popularised immediately. These bio-fertilisers may be helpful to supply N and P when required by the crops. Sometimes there is possibility of fixation in acid soil and as a result this nutrient remains unavailable to the plants. So phosphate-dissolving bacteria may release P from its fixed position and thereby help plants get it for nutritional purpose. The cultivated crops also remove huge amount of NPK and Ca from the soil.

This is high time to concentrate our ideas on the overall improvement of soil. It is experimentally proved that the bio-fertilisers are best substitutes for supplying N to the crops which help augment crop production and at the same time enrich organic matter in soil and improve its quality. Algae, water hyacinth, water chestnut, azolla are selected for their good productivity and high value components and a low cost technology is possible and desirable for the production of these biomasses. This azolla fixes atmospheric N and reduce the use of inorganic N-fertilisers. There is a recent trend among countries like Japan, Germany, India, Romania, Australia and China to pay attention to recycling of organic matter as a source of manure and energy and also to guard against environmental pollution.

Scarcity of fuel is another problem throughout the world, particularly in Bangladesh. The fuel is imported from other countries, which involved a huge amount of foreign exchange components. A combustible gas named methane, which is otherwise called biogas, could be used as an alternative to fuel produced from organic matter specially from cow-dung in a bio-gas plant. From these gas plants the degassed manure flown out as a slurry might also be used as manure. These slurry or effluent contains higher amount of NPK than the ordinary cow-dung applied as organic fertilisers. The use of dung as biogas and effluent fertiliser should be recommended in the context of Bangladesh and the people should be urged to use bio-gas and all efforts should be made by the government and non-government agencies to achieve the target so that wood would not be used at the maximum level by the villagers to meet their fuel need.

We have to save our environment where trees can play a vital role. It is also revealed that the potential value of dung as a source of bio-gas increases since people benefit from both biogas fuel and fertiliser. Therefore, instead of using cow-dung directly as fertiliser, it should be used for the production of biogas plus effluent fertiliser.

Agriculture with all its branches, viz. crop production, crop protection, livestock production, livestock disease control, fishery, forestry, farm engineering and technology, agriculture economics, communication and agricultural extension concern itself with living organisms. It is itself a living growing science and there will always be some problems. So some areas for research in agriculture and more so under prevailing Bangladesh conditions should be brought under consideration.

Lastly, for the development of agriculture in Bangladesh there has to be a definite agricultural policy since around 55 percent of the gross domestic product (GDP) comes from agriculture and the agricultural sector provides the base for the country's foreign exchange earning.

Dr. Md. Shahjahan Ali is Professor, Department of Agricultural Chemistry, Bangladesh Agricultural University.