In this article we will discuss about aeropalynological survey in India and in abroad.
1. Aeropalynological Survey In Abroad:
Systematic aeropalynological survey is carried out in various parts of the world. A list of scientists is given below (Table 10.3) who extensively surveyed the airborne allergic pollen in atmosphere.
The distributional pattern of the atmospheric pollen grains with their peak pollen seasons at different countries are given in the Table -10.4.
2. Aeropalynological Survey In India:
The first report of a comprehensive aerobiological work in India was published in 1873 by Dr. D.D. Cunningham dealing with the atmosphere of Calcutta, the then capital of India.
There was no coordinated national programme in India till 1979. In 1980 aerobiologists from different parts of India assembled to attend the workshop on “Modern Trends in Aerobiology with particular reference to Plant Pathology and Medicine” held at Bose Institute, Calcutta, where the Indian Aerobiological Society (IAS) was formed and started functioning from 31st January, 1980.
After this, the significance of aerobiological studies and the importance of pollen and spores as aeroallergens were eventually realized and such investigations were undertaken by scientists in many laboratories of India. The timing and intensity of pollen seasons differ greatly according to the local vegetation and geography, though grass pollen count is high during September to January, tree pollen during October to January and weeds between September to February.
In view of the climate, topographical and ecological diversities, the country has been divided into four biozones namely, Eastern, Western, Northern and Southern regions. The scientists who have been actively involved in aeropalynological works in different bio-zones of India are listed below. The common dominant airborne pollen types in each zone are also noted.
I. Eastern Zone:
Scientists:
S. Chanda, S. Mandal, K. Bhattacharya, S. Gupta Bhattacharya, M.R.Majumdar, N.C.Barui S. Kundu, S. Banik (all from West Bengal), K.B. Mishra (Bihar), N.I. Singh (Manipur), H.B. Baruah, B. K. Datta, G. Sharma (all from Assam).
Common pollen types:
Plains:
Acacia auriculiformis, Areca catechu, Azadirachta indica, Bombax ceiba, Borassus flabellifer, Carica papaya, Cassia sp., Casuarina equisetifolia, Cheno-Amaranths, Cocos nucifera, Dillenia indica, Eucalyptus sp., Madhuca indica, Mangifera indica, Morus sp., Phoenix sylvestris, Psidium guajava, Ricinus communis, Terminalia sp., Trema orientalis, Xanthium strumarium and grass.
Hills:
Alnus sp.; Acer sp., Betula sp., Cryptomeria japonica, Cupressus sp; Duabanga sp., Ilex sp., Pinus sp., Quercus sp., Rhododendron sp., Salix, Urticaceae and grass.
II. Western Zone:
Scientists: S.T. Tilak, G.V. Patil, S.D. Chitaley, B. N. Pande, P.B. Deodikar, P.D. Chaubal, A.R. Kulkarni, A.A. Saoji, S.A. Kalkar (all from Maharastra), R.M. Kasliwal (Rajasthan).
Common pollen types:
Azadirachta indica, Parthenium hysterophorus, Moringa oleifera, Cheno-Amaranths Prosopis sp., Casuarina equisetifolia, Eucalyptus sp., Sizygium sp., Phoenix sp., Acacia sp. and grasses.
III. Northern Zone:
Scientists:
D.N. Shivpuri, M.K. Agarwal, S.V. Gangal, A.B. Singh, B.P. Singh, C.R. Babu (all from Delhi), Vishnu-Mittre, M. Chaturvedi, K. Datta, R.D. Gaur, A. Khandelwal (all from Uttar Pradesh), A.H. Munshi (Jammu & Kashmir), Karuna S, Verma, A.K. Jain (Madhya Pradesh).
Common pollen types:
Holoptelea sp., Azadirachta indica, Casuarina equisetifolia, Cheno-Amaranthus, Ailanthus sp., Morus sp., Mimusops sp., Ricinus sp. Eucalyptus and grass.
From Jammu & Kashmir, Platanus orientalis, Narcissus, Salix are reported.
IV. Southern Zone:
Scientists:
S.N. Agashe, P.V. Subbarao, K. Manjunath, A.H. Rajasab (all from Karnataka), C. S. Reddi, Atluri J.B., R.C. Rao (all from Andhra Pradesh), B.P.R. Vittal (Tamil Nadu), P.K.K. Nair (Kerala).
Common pollen types:
Parthenium hysterophorus, Cocos nucifera, Eucalyptus sp., Casuarina sp., Ricinus communis, Cassia, Madhuca sp., Sizygium sp., Borassus flabellifer, Moringa and grass.
In India, five more or less defined seasons, i.e., Autumn, Winter, Spring, Summer and Rain are demarcated. The total number of pollen grains recorded in different months demonstrate a relatively significant variance. The changes in the frequency of pollen are probably related to the length of flowering period, pollen productivity and their extent of dispersal.
The frequency of tree pollen dominates over the other groups. The pollen grain types i.e., the constituent members, has each a peak month of occurrence. Accordingly, the dominant types can be arranged in different groups in relation to their respective high values and the corresponding seasons. These pollen types in groups can be used as marker pollen in respect to a specific season (Table 10.5).
The several works published by various researchers and the survey jointly sponsored by CSIR Centre for Biochemicals, Delhi and National Botanical Research Institute, Lucknow revealed that the Indian airborne pollen spectra demarcates three distinct Aerobiological zones.
(a) Himalayan Region:
It includes Shillong, Gauhati, Darjeeling, Kurseong of Eastern Himalaya and Almora, Srinagar of North-Western Himalaya. The index pollen types are Pinus, Cryptomeria japonica, Cedrus, Cupressus, Artemisia, Aesculus, Alnus, Betida and Quercus.
(b) Gangetic Region:
It covers different biozones like Amritsar, Bareilly, Jaipur, Lucknow, Delhi, Kolkata, Kalyani, Berhampur, Santiniketan, Howrah, Burdwan, Durgapur. The index pollen are Holoptelea, Azadirachta, Ailanthus, Morus, Cedrella, Acacia, Eucalyptus, Trema, Cassia, Peltophorum and Leguminosae.
(c) Peninsular Region:
It covers many localities like Bombay, Waltair, Vijaywada, Hyderabad, Mysore, Gulberga, Tiruchirapally, Vellore, Calicut, Bangalore. The common index types are Cocos nucifera, Borassusflabellifer, Parthenium hysterophorus, Cassia, Casuarina and Eucalyptus.