Bioassaying for ozone with pollen systems.

Abstract

Sensitivity to ozone of pollen germinating in vitro is closely correlated with ozone sensitivity of the pollen parent. Ozone-sensitive and tolerant pollen populations have been identified in tobacco, petunia, and tomato cultivars. The rate of tube elongation can be reversibly slowed or stopped by exposure to low concentrations of ozone. Tube growth rates in the presence of a range of ozone dosages, of pollen populations exhibiting differing ozone sensitivity can be measured and different growth rates can be correlated with ozone dosages. The performance of selected pollen populations can then be used to bioassay ozone in ambient air by introducing the air sample into a growth chamber where ozone-sensitive pollen in growing. Petunia and tobacco pollen are especially useful because they store well at ordinary freezer temperatures and do not require special preparation prior to storage. Modified Brewbacker's growth medium is suitable for growth of both these pollen types. Four useful cultivars are Bel W-3, ozone-sensitive and Bel B, ozone-tolerant tobacco, and White Bountiful, ozone-sensitive and Blue Lagoon, ozone-tolerant petunia. Observations can be made directly by using a TV scanner, or by time lapse or interval photography. Year-round pollen production can be achieved in the greenhouse. Harvested pollen can be tested, packaged, and transported to user facilities without loss of vigor. Pollen populations are inexpensive to produce, respond reliably, and are simple to use as a bioassay for air quality.ImagesFIGURE 2.FIGURE 3.FIGURE 4.

A Review of the Effects of Major Atmospheric Pollutants on Pollen Grains, Pollen Content, and Allergenicity

“…For example, when artificially polluting Ambrosia artemisiifolia pollen with O 3 , Pasqualini et al could clearly show that the viability was rather low on 7-day O 3 − fumigated pollen (39%) compared to the control sample (56%) [ 157 ]. On pollen of cultivated plants (tomato, tobacco, and petunia), Feder showed that the pollen viability can be reversibly slowed or stopped by exposure to low concentrations of O 3 [ 158 ]. O 3 effect can also be observed in Lolium perenne pollen.…”

Quantifying the effects of ozone on plant reproductive growth and development

“…Ozone entry into the apoplastic space in reproductive structures leads to ROS production, which can lead to changes in the stigmatal surface and cell membranes (Feder & Shrier, ). The ROS also affect the ability of pollen to germinate on the stigmatal surface (Mumford et al ., ; Harrison & Feder, ; Krause et al ., ; Feder, ; Feder et al ., ; Benoit et al ., ; Hormaza et al ., ). Moreover, ROS‐mediated changes in the cellular redox environment can potentially lead to changes in pollen tube growth and guidance, which is critical for fertilization of the embryo.…”

A first test of elemental allelopathy via heterospecific pollen receipt

“…Such tests are especially important because metal hyperaccumulators occur in many systems across the globe and are increasingly used in phytoremediation (Sarma, 2011) where they may transfer pollen to native species if shared pollinators are not deterred by metals (Meindl and Ashman, 2014; Hladun et al, 2013). Moreover, because gametophytes and sporophytes share many genes and have similar responses to environmental stressors (such as temperature and salinity) (e.g., Herrero and Johnson, 1980; Feder, 1981; Rutley and Twell, 2015) this study opens the window on an underappreciated possibility that chemical mediation of sporophyte interactions also plays a role in pollen interactions on the stigma.…”