Chlorosis, Photosynthesis, and Transpiration of Azalea Leaves After Azalea Lace Bug (Heteroptera: Tingidae) Feeding Injury

Abstract

Feeding injury caused by nymphs, males and females of the azalea lace bug, Steplwnitis pyrioides (Scott), reduced rates of photosynthesis and transpiration in 'Delaware Valley White' azalea, RllOdodendron mucronatulIl leaves. Females caused substantially more leaf feeding injury than males or nymphs. S. pyrioides was observed to insert stylets through stomata on the lower leaf surface and to feed almost entirely on upper palisade parenchyma tissue by piercing and removing cell contents. Lace bug feeding increased leaf stomatal resis tance which indicated that gas exchange was restricted by stomatal closure. Feeding injury also reduced leaf chlorophyll content and photosynthetic capacity of remaining chlorophyll, but did not consistently affect chlorophyll a:b or specific leaf weight. Net leaf photosynthesis was negatively correlated with stomatal resistance and positively correlated with both chloro phyll content per unit leaf area and photosynthetic rate of remaining chlorophyll. These results indicated that S. pyrioides reduced leaf photosynthesis in azalea by damaging palisade paren chyma which restricted gas exchange through stomata and reduced leaf chlorophyll content and photosynthetic capacity of remaining chlorophyll.

Impact of scale insect infestation on the content of photosynthetic pigments and chlorophyll fluorescence in two host plant species

“…Losses of chlorophyll content due to insect herbivory have been quantified in other hemipterans using similar chlorophyll analyses. Other researchers (Buntin et al 1996;Morales et al 2002;Goławska et al 2010) have explored the leaves of stressed plants apparently with less synthesised chlorophyll content, and these changes may be part of the adaptive responses. Chlorophyll a and b concentrations can be significantly higher in non-infested leaves with both short and long infestations of plants compared to the infested ones (Goławska et al 2010).…”

“…They confirmed that the permanent impairment of photosynthetic photochemistry was restricted to the damaged areas on the leaf. Buntin et al (1996) showed that feeding injury caused by Stephanitis pyrioides (Scott) reduced the chlorophyll content and adversely affected net leaf photosynthesis and transpiration in azalea. The feeding of Bemisia tabaci Gennadius reduced the leaf photosynthesis in tomato leaves by decreasing the content and photosynthetic capacity of chlorophyll (Buntin et al 1993).…”

Seasonal population fluctuations of the diamondback moth,Plutella xylostella(L.) (Lep.: Plutellidae) on different cauliflower cultivars

“…Shuster et al (1980) showed tolerance of strawberry cultivars to two spotted spider mites and concluded that content of chlorophyll in tolerant cultivars is not significantly decreased despite the high density of the pest. Buntin et al (1996) by studying the effect of pear lace bug damage on photosynthetic rate and leaf's gas exchange concluded that the effects of pear lace bug feeding on parenchyma tissue and causing damage are increased stomatal resistance and limiting of gas exchange and decreased leaf chlorophyll rate.…”

Development and population growth of Stephanitis pyri (F.) (Heteroptera: Tingidae) at five temperatures

“…There are more studies on Stephanitis pyrioides (Scott), the most important pest of azaleas (Braman et al 1992;Shrewsbury and Raupp 2000;Klingeman et al 2000aKlingeman et al , b, 2001aStewart et al 2002) and some other species, like Corythucha sp., (Braman and Pendley 1993;Rédei et al 2004;Bernardinelli 2006) in the USA and Eastern Europe. Buntin et al (1996) observed that S. pyrioides insert stylets through stomata on the lower leaf surface and feed almost entirely on upper palisade parenchyma tissue by piercing and removing cell contents. Forecasting models based on heat accumulation units should be developed for S. pyri like those reported for the azalea lace bug by Braman et al (1992).…”