Association of stomatal frequency and morphology in Lycopersicon species with resistance to Xanthomonas campestris pv. vesicatoria

Abstract

Study of the stomata and leaf epidermis of eight Lycopersicon species has revealed a relationship between frequency of stomata, stomatal size and some morphological leaf characteristics, and resistance to bacterial leaf spot caused by Xanthomonas campestris pv. vesicatoria. Significant correlations were found between the stomatal frequency in both adaxia! and abaxial leaf epidermis and the number of bacterial lesions per leaf area (/-= 0-70 and 0-68, respectively) and the frequency of stomata in both adaxial and abaxial epidermis and disease incidence (percentage of diseased plants) {r -0-^1 and 080, respectively) for all the Lycopersicon species and one hybrid tested. A correlation was also found between disease incidence and number of bacterial lesions per leaf area (/'^O-SS). The length and width of stomata were correlated with frequency of stomata in adaxial and abaxial epidermis (/• = 0-85, 0-75. 0-89 and 090, respectively). The stomatal width was correlated with the number of bacterial lesions per cm-(/• = 0'82; P = 0-0065). Scanning electron microscopic studies of the leaf surface and stomata indicated that other morphological features such as the raised stomatal complex in L. hirsutwn and persistent, hydrophobic waxy coating of the epidermis in L. peruvianum may also be relevant in disease response.

Leaf Waxes of Cassava (Manihot Esculenta Crantz) in Relation to Ecozone and Resistance to Xanthomonas Blight

“…Thus, slightly lower numbers of stomata between veins on the abaxial surface of the resistant genotype which are additionally occluded by wax in both genotypes might contribute to lower numbers of bacteria entering the intercellular space in the resistant plant. In bacterial leaf spot of tomato, stomatal frequency and morphology were shown to be associated with resistance to the disease (Ramos et al, 1992). For a conclusive interpretation of the role of leaf stomata in cassava bacterial blight infection it should be considered, that stomata distribution might change under differing environmental conditions.…”

Xanthomonas

“…Thus, a peach cultivar with high susceptibility towards X. c. pv. Ramos et al (1992) found a correlation of the stomatal width as well as the stomatal frequency with the number of lesions caused by X. c. pv. Similar Initial events in pathogenesis 201 differences in stomatal aperture have been reported in X. c. pv.…”

“…vesicatoria was obtained by Ramos et al (1992). Evidence for a structurally conditioned resistance of Lycopersicon species to X. c. pv.…”

Padrão estomático de Capsicum ssp. resistentes e suscetíveis a Oidiopsis haplophylli

“…Resultados similares foram observados nos patossistemas Lycopersicon spp.-Xanthomonas campestris pv. vesicatoria (14), amendoim-Phaeoisariopsis personata (18) e triticale-Tilletia indica (7).…”