Photosynthetic, metabolic and growth responses ofTriumfetta rhomboideato coal-smoke pollution at different stages of plant ontogeny

Abstract

Coal-smoke emissions affected photosynthesis, N-metabolism and growth characteristics of Triumpfetta rhomboidea, as observed at pre-flowering, flowering and post-flowering stages of plant growth. The net photosynthetic rate and stomatal conductance decreased, whereas intercellular CO 2 concentration increased under pollution stress. The amounts of photosynthetic pigments in leaves were consistently less, up to 35% for chlorophylls and 84% for carotenoids. Nitrate level was raised while NR activity and protein contents in leaves declined at the polluted site at each growth stage. Sugar content was always lower at the polluted site in roots and stem but sizably higher in leaves, thus showing a failure of the process of photosynthate translocation. The sulphur level in roots, stem and leaves increased consistently. The leaf area was conspicuously reduced, leading to a significant loss in the total photosynthetic surface, despite an increase in the stem length and the number of leaves in the stressed population.

Assessing the Indoor Pollutants Effect on Ornamental Plants Leaves by FT-IR Spectroscopy

“…In accordance with the results of other studies by Iqbal et al [45], for the plants maintained in polluted environment the overall plant height and number of new leaves per plant was higher (for example, the height mean values increased with 2, 1.8, and 2 cm for polluted Ficus elastica, Dracaena deremensis, and Sansevieria trifasciata, respectively). This may be due to the increased age of the plant and stress pollution.…”

The Effect of Air Pollution on some Biochemical Parameters of Leaves of Three Tree Species Growing in the Industrial Area in Jeddah, Saudi Arabia

“…The lower amount of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids under polluted environment were also noted in several other studies (Singh et al 1985;Singh et al 1990;Malabari et al 1991;Dhir et al 1999;Nighat et al 1999Nighat et al , 2000Saquib, 2008;Iqbal et al 2010;Chauhan and Joshi, 2010). Several researchers have reported reduced carotenoid content under air pollution (Joshi et al, 2009;Tiwari et al, 2006…”

Behavioral responses of leaves and vascular cambium ofProsopis cineraria(L.) Druce to different regimes of coal-smoke pollution

“…The increase may be due to a greater allocation of photosynthates towards the apical meristem, as was the case with Triumfetta rhomboidea (Iqbal et al 2009). It is also likely that sulfur requirement of plants is better met in the SO 2 -rich environment, given that much of our soil is sulfur deficient (Wali et al 2007).…”

“…Chlorophyll a may be more sensitive to pollution effect than chlorophyll b in some species (Mandre and Tuulmets 1997), while the reverse may apply to others (Ali et al 2008;Nighat et al 2008;Iqbal et al 2009). Both the chlorophylls may also show a comparable sensitivity (Singh et al 1990).…”

“…Internal CO 2 concentration, normally higher under polluted conditions, attained the maximum in pre-monsoon season. This could facilitate stomatal closure, thus lowering the stomatal conductance (Swanepoel et al 2007;Iqbal et al 2009). …”