Effect of vehicular traffic on pollen size and viability of Apocynaceous plant species

Abstract

Vehicular traffic adds up different kinds of contaminants like heavy metals, polyaromatic hydrocarbons, gaseous toxins etc. to the atmosphere. Pollen grains of different plants have been found to be sensitive to these pollutants, which show varied effects on their viability, and size and hence can be used as bioindicators of air pollution. Keeping this in mind, the present work was designed to measure the pollen viability and pollen size of three common roadside plants, namely Alstonia scholaris, Nerium oleander and Tabernaemontana divaricata belonging to Apocynaceae family growing at seven sites of Amritsar city with varying levels of traffic stress. Pollen viability and pollen size were studied using 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining method. The percentage of pollen viability of A. scholaris ranged from 32.45% to 65.74%, for N. oleander it ranged from 30.3% to 45.11% and for T. divaricata it ranged from 14.31% to 49.62%. Pollen size ranged from 22.86 to 23.94 µm for A. scholaris, 29.58 to 32.17 µm for N. oleander and 29.83-32.43 µm for T. divaricata. Pollen viability was found to be inversely proportional to a load of traffic at a given site whereas no remarkable variation was found in pollen size. For A. scholaris, a significant negative correlation (r= -0.762, p≤0.05) was observed between pollen viability and traffic load, while for other two species correlation between pollen viability and traffic load was not statistically significant at p≤0.05.

Response of Sweet Cherry (Prunus Avium L.) Pollen Grains to Vehicular Exhaust Pollution at Quetta, Balochistan, Pakistan

“…Many other researchers, including Gottardini et al (2004), Higashitani (2013), Rezanejad (2013), Paupiere et al (2014), have concluded that the vehicular emission and other atmospheric generated pollutants significantly influence the pollen grain production, pollen size, structure and its viability of different plant species. Kaur and Nagpal (2017) reported inversely proportion between number of traffic and pollen viability for Alstonia scholaris, Nerium oleander and Tabernaemontana divaricata at selected study sites.…”

“…Pollen size was determined by micrometry method. A visual micrometer was fixed on light microscope and measurements of pollen grain size were determined under the magnification of 400×, as per procedure carried out by (Kaur and Nagpal, 2017). A minimum of 500 pollen grains were examined from each plant species.…”

“…to the atmosphere. Pollen grains of different plants have been found to be sensitive to these pollutants, which show varied effects on their viability, and size and hence can be used as bioindicators of air pollution (Kaur and Nagpal, 2017). This research directed to the knowledge that the downcast growth and developmental potential of pollen in reply to many poisonous environmental pollutants released by traffic can be introduced as a good directory of air cleanliness.…”

“…Hungarywhich were rounded in shape, were counted as viable pollen grains. At least 500 pollen grains were studied by each plant (separately from polluted and control sites) and the experiment was repeated for three times and an average was calculated(Kaur and Nagpal, 2017). Further the viability of pollen grains was also tested by the germination of pollen grains(Iyer and Bholay, 2015) and percentage of viable pollen grains was calculated by the following formula:…”

Climate change and allergic diseases: An overview

“…Cassia sophera is the most widely distributed and common variety growing in the tropical region (62) and can be used as an indicator species because of its relative abundance and the effect imposed on it by the reduction in viable pollen formation (63)(64)(65)(66)(67)(68)(69). Moreover, this herb has been selected for its wide use, ready availability under controlled and environmentally stressed conditions, and its height being below the exhaust pipe of vehicles.…”