Effects of Cherry Leaf Spot on Photosynthesis in Tart Cherry ‘Montmorency’ Foliage

Abstract

Results described here span a total of three field seasons and quantitatively depict the effects of an economically important fungal pathogen (Blumeriella jaapii) on tart cherry (Prunus cerasus 'Montmorency') leaf physiology. For the first time, leaf photosynthesis, stomatal conductance (g(s)), maximum ribulose-1,5-bisphosphate carboxylation rate (V(cmax)), and maximum electron transport (J(max)) were measured as functions of visible cherry leaf spot disease (CLS) severity. Defined as the proportion of chlorotic and necrotic tissue per leaf, CLS severity was estimated from leaves of mature 'Montmorency' trees in 2007, 2008, and 2009. Briefly, as visible disease severity increased, all of the leaf-level physiological parameters decreased significantly (P < 0.01) and disproportionately. Thus, the effects of visible symptoms on leaf photosynthetic metabolic function encroached upon asymptomatic tissue as well. Impairment of photosynthetic metabolism in 'Montmorency' tart cherry leaves due to CLS appears to be mediated through disproportionately large perturbations in g(s), V(cmax), and J(max). These findings offer a new perspective on the amount of damage that this serious disease can inflict.

Cherry Leaf Spot Disease Management in Ornamental Cherries in Mid-Tennessee.

“…Host resistance is the most recommended method for controlling CLS, and the sources of resistance are available in fruiting cherries (McManus et al 2007;Gruber et al 2012;Stegmeir et al 2014). Use of non-chemical control methods such as the destruction of previously infested leaf debris has also been studied as a potential method for eliminating the source of inoculum in leaf debris (Holbs 2013;Holb et al 2014).…”

Changes in leaf gas exchange and chlorophyll a fluorescence on soybean plants supplied with silicon and infected by Cercospora sojina

“…Overall, the infection of leaves of plants from cultivar Conquista which estimates the ratio of the opened reaction centres of the PSII (Schreiber, Bilger, & Neubauer, 1994 1991; Berger et al, 2007;Gruber, Kruger, & McManus, 2012;Pinkard & Mohammed, 2006;Rahoutei et al, 2000;Resende et al, 2012). oryzae and C. sublineolum, respectively, impaired photosynthesis, but for a lesser extent on plants supplied with Si (Dallagnol et al, 2013;Resende et al, 2012).…”

“…The negative effect of pathogens infection on the physiology of their hosts was extended to nonsymptomatic leaf tissue (Bastiaans, ; Berger et al., ; Gruber, Kruger, & McManus, ; Pinkard & Mohammed, ; Rahoutei et al., ; Resende et al., ). However, in sharp contrast with the results of the present study, Gao et al.…”

Assessing the Consequences of Microbial Infection in Field Trials: Seen, Unseen, Beneficial, Parasitic and Pathogenic

“…Disease symptoms can have direct impacts on key host metabolic processes such as photosynthesis or nutrient uptake largely through loss of leaf area for plant processes e.g., [4,5]. However, infection prior to symptom expression (or even incompatible host-pathogen interactions) can have significant effects on host metabolism [6][7][8], whilst disease symptoms on crop structures that are not yield limiting may have little or no effect [9]. As such, it is becoming clear that relying solely on visible disease symptoms as a proxy for disease severity or to inform yield loss models will impose significant limitations on our understanding of microbial interactions with crop plants and their effects.…”