Effects of Ozone and Sulfur Dioxide on Tuber Yield and Quality of Potatoes

Abstract

Air pollution injury of the potato plant (Solanum tuberosum L.) has been documented previously, but potato yield losses have not been estimated in replicated experiments having controlled exposures to ozone (O3) and sulfur dioxide (SO2) A controlled‐environment study involving the speckle‐leaf‐sensitive cultivar ‘Centennial Russet’ was conducted to examine the effects of chronic exposure to O3 and SO2 on plant growth and tuber yield and quality.Ozone, at the highest seasonal dose (44.2 ppm‐h), reduced leaf dry weight 48%, root dry weight 58%, tuber number 38%, and total tuber yield 45%. Lower exposures affected these parameters in linear proportion to the O3 dose. Mean stem (minus leaves) dry weight, tuber dry weight, tuber dry matter percentage, partitioning of dry matter to tubers, and tuber sugar concentrations were not affected. Tuber N concentration increased linearly by up to 21% as the O3 dose increased. Plants grown outside of chambers in ambient air showed effects consistent with results obtained within the chambers. The plants grown outside received a total seasonal O3 dose of 50.4 ppm‐h and produced 58% less tuber yield than filtered air control plants.Plant responses to SO2 exposure were much less pronounced than their responses to exposure to O3. However, leaf symptom development in O3‐treated plants was markedly intensified by the presence of SO2. Small reductions in tuber yield and mean tuber size, but not in tuber number, were observed in SO2‐treated plants. Tuber N concentration increased slightly in SO2‐treated plants.A significant O3 × SO2 interaction was observed in the case of tuber N concentration only; SO2 accentuated the O3‐induced increase in N content.

Elevated CO2 increases biomass and tuber yield in potato even at high ozone concentrations

“…These changes reduced the total weight of tubers produced under elevated O 3 in the absence of effects on overall tuber number. Ozone‐induced reductions in total tuber number have also been observed in experiments using container‐grown plants (Foster et al. , 1983b; Pell & Pearson, 1984), although Foster et al .…”

“…In tests of the O 3 sensitivity of 12 potato cultivars in the United States, Heggestad (1973) concluded that the more sensitive varieties originated from areas experiencing low ambient O 3 concentrations. In OTC experiments in California, Foster et al . (1983b) showed that a cumulative dose of 44.2 µmol mol −1 h O 3 induced severe foliar damage and reduced tuber yield by 45%; however, other studies of defoliation by Colorado beetle indicate that potato is capable of compensating for extensive foliar damage (Hare & Moore, 1988) as no yield losses occurred even after 50% defoliation.…”

“…, 1998). Exposure to ozone may also decrease tuber number and yield at maturity (Foster et al. , 1983b).…”

“…Although the detrimental effects of ozone may vary greatly between species and cultivars (Barnes et al , 1999;Black et al , 2000), exposure generally induces premature leaf senescence, so reducing the green leaf area available for assimilate production and hence crop yield (Soja & Soja, 1995;Finnan et al , 1998). Exposure to ozone may also decrease tuber number and yield at maturity (Foster et al , 1983b).…”

Effects of Tropospheric Ozone on Potato Plants Protected by the Antioxidant Diphenylamine (DPA)

“…Severely injured leaves became chlorotic, followed by progressive necrosis, defoliation and accelerated plant death (Foster et al, 1983). However, estimates of visual injury did not correlate with yield reduction for wheat (Decoteau et al, 1986) and spinach (Heagle et al, 1979).…”