Responses of Some Crops to Air Pollution by Using Air Pollution Tolerance Index

Abstract

Responses of plants toward the air pollution were assessed by air pollution tolerance index (APTI). APTI is calculated from the values of different biochemical parameters of plant leaves such as relative water content, total chlorophyll content, ascorbic acid content, and leaf extract pH by using standard methods. Plants with a high index value were tolerant of air pollutants and vice-versa. Based on their indices, different plant groups were categorized into sensitive, intermediate, and tolerant. This study was aimed to identify the most tolerant and sensitive crop plants. The present study was carried out to evaluate the air pollution tolerance index (APTI) of eight economically important winter crop plants. Plants were cultivated in polluted site 1 (Thamel), polluted site 2 (Banasthali), and less-polluted site (Phutung) in Kathmandu based on vehicular movement. The result of the study showed higher APTI values in polluted site 1 than in less-polluted sites and polluted site 2. Among the studied species, Brassica juncea (10.69±1.07), Brassica campestris (10.45±0.88), Triticum aestivum (9.74±0.77) and Hordeum vulgare (9.64±1.00) respectively were recorded high APTI values indicating resistance to pollution and Trigonella foenum-graecum (7.52±2.08) with the lowest APTI value indicating sensitive to pollution. The impact of the air pollutants on crop productivity was also measured from the selected crop plants. The result revealed that plant growth was found to be reduced in polluted sites. And Triticum aestivum (64.48±31.53

kg ha -1 ) was a high productivity crop plant while low was Trigonella foenum-graecum (2.09±0.68

kg ha -1 ). The response of crop plants was varied in species, studied sites, and level of pollution. Hence, this study helps to identify the tolerant crop plant which can act as a good absorbent of air pollutants.