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1- POWER: SUPPLY-DEMAND SITUATION
2-
THE WHEAT CRISIS
3-
RADIOISOTOPES
4-
TEXTILE INDUSTRY
5- ECONOMIC PERFORMANCE: A REVIEW
6- SEAFOOD EXPORTS

 

IMPORTANCE OF RADIOISOTOPES IN AGRICULTURE

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By Dr. S.M ALAM
Dec 08 - 14, 2003
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Radioisotopes emit some extraordinary types of energy in form of rays (alpha, beta and gamma), which are very helpful to human beings in minute quantity. These rays are invisible spontaneous and penetrating. Their presence can be easily detected with the help of the latest devices such as Geiger Muller and Scintillation Counters. These instruments are used for the detection of even, the very tiny or minute quantity of radioactive element present. Thus, new tiny tool radioactivity is proving very helpful in several fields of daily uses such as medicine, agriculture and industry. Today, these new tools unlocking the secrets of many human well beings problems which could never have been possible by conventional means. Many scientific researches are being conducted all over the world putting radioisotopes into use with successful scientific achievements. This article deals specially with the use of radioisotopes and radiations in the field of agriculture.

Presently, the radioisotopes are being widely used in the field of agriculture than in any other field of science and their application is leading us to the solution of many agriculture problems in a shorter time and more precisely. Thus, radioisotopes have become a very important aid to scientists dealing with the solution of agricultural problems. In addition to this, radioactive tracers and radiation sources have become indispensable to all the intricate agricultural research problems. Radioisotopes and radiations give us the chance to clear the events that once were mysterious in the nutrition and growth of plants and evolution of new crop varieties. They help us to clear the casual factors, which produce ill-effects to the plants in different ways.

In agriculture, radioisotopes are used in the nutritional studies of major and minor elements, milk production, mechanism of photosynthesis studies. Plant protection, plant pathology, action of insecticides, uptake of fertilizers, ions mobility in soil, and plants and food preservation. In order to determine the correct nutrition for a plant we need to know the exact soil plant relationship and the factors involved therein.

Application of radioisotopes and radiation sources in agricultural research has especially the following advantages:

i) With the help of radioisotopes we can easily locate the presence of a single atom and molecule and their movement. Hence, they give research workers the opportunity to follow up step by step all kinds of processes that are related to the nutrition of plant from germination to maturity.

ii) Very small quantities of labeled nutrients can be accurately measured in presence of large quantities of other nutrients.

iii) The location of materials can be identified by radio-autography.

iv) Tracer technique enables one in tracing those elements taken by the plants accurately and precisely.

v) It also helps to study accurately the effect of one element upon the absorption of another and their interaction by plants and now it has become very easy to study properly the phenomenon of interaction among the mineral nutrients.

The production of radioisotopes by nuclear reactors and other atomic installations have increased the use of radioisotopes in the field of agriculture. To obtain an increased yield from the soils by applying fertilizers, one has got to determine the fertility status of the soil, which appears to be unproductive. Radioactive phosphorus is used in most of the investigations that are carried out to determine the P-status of the soils. Several problems can be solved by this study such as comparison of various fertilizers, influence of particle size, placement, time of application, doses, absorption by plants and the reaction of the applied fertilizer in the soil.

By using radioactive phosphorus research workers have succeeded to distinguish between soil phosphorus and the fertilizer phosphorus, taken by the plants. Radioisotopes like Fe, Mn, K, Ca, N, Rb, C, Cs, Si and Sr etc. and other macro and micro-elements have also been used by workers in order to find out their movement in different types of soils and also their position in different clay fractions of the soils. The radioisotope method is very reliable and helpful in determining fertility level of soil. Thus, the application of radioactive elements in agriculture has received tremendous importance in interpreting certain aspects of soil fertility and other intricate problems. Radioisotopes have also helped the investigation of the effect of such factors as cultivation, irrigation methods and time on the root system of plants.

Recent studies with radioisotopes have also shown that with many crops, supply of plant nutrients through the leaves is more quick and effective than the application in soil. For example, it has been found that a nutrient, which is hardly absorbed upto 10% by root, can be absorbed upto 90% when applied on leaves. Experimentally, it has been found that the absorption of nutrients by leaves takes place not only during the day time but also at night time. Through isotope technique it is possible not only to determine the amount of nutrient that are taken by plants, but it also gives the opportunity to know about their movement and their places of accumulation. In the plants, mostly radiophosphorus has been used for this kind of research works and the results have shown that absorption speed of this nutrient was more than the expected.

Radioisotopes and radiation is used in mutation induction. Mutation is a sudden heritabic changes of the hereditary factors organs on the chromosomes of the organisms. The employment of radiation to induce hereditary variants is a useful tool of potential value in agriculture. We have been able to show conclusively that, with radiations changes can be brought about in the organization of the hereditary make up that are useful in plant improvement.

Radioisotopes and ionizing radiations are of inestimable value for obtaining an insight into ecological habits of insects. With the aid of radioisotopes we can find out population density the maturity rate during different stages of the life cycle, modes of dispersal, movement and migration, flight range hibernating places, egg living sites relation to predators, parasites, feeding? mating habits and disease transmission etc.