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The aim of this study was to assess the effect of air pollution on road side fruit plants (Prunus avium L.) palynology. Flower samples were collected from polluted (1-2 m away from the edge of Quetta to Hunna Urak road) and for the comparison from non-polluted sites (250-300 m away from the same collection site). During the investigation different pollen parameters including pollen umbers/production, pollen size, pollen tube growth, pollen viability, pollen regularity and pollen protein contents were used through different methods. Results indicated that pollen grains of Prunus avium L. were very sensitive to automobile air pollution. Consequences showed significant reduction in numbers and sizes of pollen grains, pollen tube length and pollen viability of polluted site with respect to the control site. Maximum irregularity in pollen morphology and low pollen protein contents were also recorded from the polluted site. Moreover, results also designated that vehicular pollution increases the resting period of pollen grains for 1 to 3 h. So the different attributes of pollen grains can be used as sensitive bioindicators of adverse factors in botanical environment and this leads to the idea that reduction in the development and potential of pollen grains in response to various poisonous environmental pollutants can be exploited as a good index of air purity.

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On several alkaline calcareous soils, Zn and Cu deficiency occurred mainly ill lowland rice (Oryza sativa L.) and was rarely found in wheat (Trilicum aestivum L.). Zinc and Cu requirement of plants was not responsible as the critical Zn and Cu contents ill tops of the two plant species were almost similar i.e. 17.4, 6.5 and 14.5, 5.6 ppm respectively. Neither did rice absorb Zn and Cu less efficiently. On the contrary, their rates of absorption in rice were double than in wheat. They were 22.2, 6.3 and 10.2, 3.3 ng atoms/g fresh root/h respectively in the two plant species. Flooded soil conditions appeared to be responsible for Zn and Cu deficiency in rice as their deficiency was found maillIy in plant samples collected from continuously flooded fields. The mechanism is not known.Both Zn and Cu inhibited uptake of each other in wheat on most of the soils. In rice, only applied Zn depressed Cu uptake but Cu had generally little effect on Zn uptake. Little Cu inhibition of Zn uptake in lowland rice seems to be related to flooded soil conditions. The mechanism is yet to be known. The antagonising element accentuated the deficiency of the other element both in wheat and rice and severely reduced their yields on soils marginal to deficient in Zn or Cu supplies. I t is recommended that their soil availability status should be thoroughly considered before their fertilizers are applied.

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Indian siris, Albizia lebbeck (L.) Benth. (Fabaceae: Mimosoideae) has significant importance to human beings for its multipurpose use. Insects play a crucial role in the pollination biology of flowering plants. In the current study, we studied the pollination biology of A. lebbeck with special reference to insect floral visitors. The effectiveness of floral visitors was investigated in term of visitation frequency, visitation rate and pollen load during 2012 and 2013. In the second experiment, effect of pollinators on yield of A. lebbeck was studied in open and cage pollination experiments. Floral visitor fauna of A. lebbeck included eight-bees, two wasps, two flies, and two butterflies species. Among them, Apis dorsata, Apis florea, Amegilla cingulata, and Nomia oxybeloides had maximum abundance ranging from 349–492, 339–428, 291–342 and 235–255 numbers of individuals, respectively during two flowering seasons. A. dorsata had the highest visitation frequency (6.44 ± 0.49–8.78 ± 0.48 visits/flower/5min) followed by Amegilla cingulata (6.03 ± 0.43–7.99 ± 0.33 visits/flower/5min) and A. florea (3.61 ± 0.31–4.44 ± 0.18 visits/flower/5min). A. dorsata, N. oxybeloides, and Amegilla cingulata had the highest visitation rates (18.904 ± 1.53–11.43 ± 1.17 flower visited/min) and pollen load (15333 ± 336.22–19243 ± 648.45 pollen grains). The open pollinated flowers had significantly higher capsule weight (4.97 ± 0.21 g), seed weight (1.04 ± 0.05 g), seed numbers per pod (9.80 ± 0.34) and seed germination percentage (84.0 ± 1.78%) as compared to caged flowers. The results suggested bees especially A. dorsata, N. oxybeloides and Amegilla cingulata could be effective pollinators of A. lebbeck.

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