Pollen control

Forest systems also act as sources of CO2 when controlled or uncontrolled burning and decay of litter occur. In addition, release of ethylene occurs during the flowering of various species. One additional form of emission to the atmosphere is the release of pollen grains. Pollen is essential to the reproductive cycle of most forest systems but becomes a human health hazard for individuals susceptible to hay fever. The contribution of sulfur from forests in the form of dimethyl sulfide is considered to be about 10-25% of the total amount released by soils and vegetation (12). 

Air treatment Any technique used to control the temperature, moisture content, or levels of dusts, gases, vapors, pollens, bacteria or viruses in air. 

Remarkably, Brassica napus pollen was reported to have a 22 kDa cutinase that cross-reacted with antibodies prepared against F. solani f. pisi cutinase [134]. Although a 22 kDa and a 42 kDa protein that catalyzed hydrolysis of p-nitrophenyl butyrate were found in this pollen, only the former catalyzed cutin hydrolysis. Immunofluorescence microscopic examination suggested that the 22 kDa protein was located in the intine. Since the nature of the catalytic mechanism of this enzyme has not been elucidated, it is not clear whether this represents a serine hydrolase indicating that plants may have serine and thiol cutinases. The role of the pollen enzyme in controlling compatibility remains to be established. 

Murphy, S.D. (1999). Is there a role for pollen allelopathy in biological control of weeds. In Allelopathy Update, (Ed., S.S. Narwal) Vol. 2 321-332. Science Publishers, Enfield, Plymouth, USA. 

Other compounds are used, however sulphates are avoided (e.g. as in MgS04) and nitrates (e.g. as in CaNOs) due to the risk of forming more acids that make the pH hard to control. For some pollen, this makes little difference but other species are more sensitive to changes in pH. 

Little is known about the effect of leaching on distribution of SOM with depth, which is unfavorable for evaluating the potential capacity of soil to sequester carbon. Sporopollen (pollen and spores) are abundant in upper soils, and their vertical distributions are controlled substantially by leaching (Zheng et al. 2002). The distribution of sporopollen with depth may be a useful index of leaching potential. We intended to evaluate the effect of leaching on SOM vertical distribution, based on variations in SOC concentration and SOM 14C apparent age with depth. The distribution of sporopollen with depth can serve as a reference for our evaluation. 

Protocol updated from Krolak et al. (49) and Dashek and Mills (50). Controls (a) Germinate pollen without [14C]-pro and process as before, (b) Construct a radioautographic sandwich with collodion lacking pollen, (c) Expose a slide coated with Kodak NTB-2 Nuclear Track Emulsion to light and develop emulsion with D-19. (Sample autoradiographs are presented in Fig. 3.)... 

Fig. 3. Lightmicroscope radioautographs ofintact tubes from pollen germinated 4 h in a medium containing [14C]-proline with or without the proline analogue, azetidine-2-carboxylic acid (AZC). A = 1.0 mM AZC, B = 0.1 mM AZC, C = 0.01 mM AZC, D = 0.001 mM AZC, E = Control. From Dashek and Mills (50), with permission. 

Pollen allelopathy can find utilization in field cultivations that could contain pollen of allelopathic crops or weeds. Pollen allelopathy could be an effective method for annual weed control that reproduce, at least in part, via wind pollination and flower concurrently with the allelopathic species. The effects of allelopathy should result in the loss of genetic variation and so in reduction of reproductive ability, but some plants are probably able to detoxify the pollen allelochemicals (Murphy and Aarssen 1995a, b). Murphy and Aarssen (1989) suggested possible delaying of weed flowering at later, less favorable times of the season or diurnal period, so decrease in weed pressure. However, infestation by perennial weeds can worsen due to compensation of pollen allelopathy through increase in the formation of rhizomes. 

Denture stomatitis. Coconut soap, associated with 05% sodium hypochlorite, used by patients for 15 days, significantly reduced clinical signs of denture stomatitis and was effective in controlling denture biofilm . Desensitization effect. Saline extract of the dried pollen, administered subcutaneously to 96 allergic adults at variable doses, produced a clinical improvement and decreased IgE levels ". 

Placebo-controlled immunotherapy with Cocos nucifera pollen extract. Int Arch Allergy Immunol 1994 103(2) 194-201. 

OE231 Casanovas, M., E. Guerra, C. Moreno, R. Miguel, E. Maranon, andj. C. Daza. Double-blind, placebo-controlled clinical trial of preseasonal treatment with allergenic extracts of Olea europaea pollen administered sublingually. J Investig Allergol Clin Immunol 1994 4(6) 305-314. 

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