Possible rôle of sugars in restriction of lesion development in finger millet leaves infected with Helminthosporium tetramera

Plasticity of Phymatotrichopsis omnivora infection strategies is dependent on host and nonhost plant responses

“…In addition, the current transcriptome profiling study is more comprehensive than the previous one where an Affymetrix microarray (Affymetrix, Santa Clara, CA, USA) was used, which did not have all the M. truncatula genes on it. Nevertheless, both the studies strongly suggest that P. omnivora turns down the defence signalling pathways for success- (Vidhyasekaran, 1974). In a more recent study, cold acclimatized grasses accumulated sugars that enhanced their resistance to fungal pathogens (Rapacz, Pla_ zek, & Niemczyk, 2000).…”

“…Several studies have indicated that sugars act as signalling molecules during fungal attack. Finger millet leaves with enhanced levels of carbohydrates from plants grown in continuous light or 12‐hr photoperiod cycle had enhanced carbohydrates and enhanced resistance to Helminthosporium tetramera (Vidhyasekaran, ). In a more recent study, cold acclimatized grasses accumulated sugars that enhanced their resistance to fungal pathogens (Rapacz, Plażek, & Niemczyk, ).…”

The role of sugar signaling in plant defense responses against fungal pathogens

“…Some abiotic stresses at the same time reduce the level of sugar and plant resistance to fungal infections. Vidhyasekaran (1974) tested the influence of photoperiod on carbohydrate content in finger millet leaves and their resistance to the disease caused by Phytophthora infestans. In plants kept in continuous light, carbohydrate content was twice as high and the disease index was 20-fold lower than in plants kept in continuous darkness.…”

Plant Responses to Sugar Starvation

“…For example, the link between low sugar content and plant sensitivity to fungal diseases known as "low-sugar diseases", was first reported over 50 years ago by Horsfall and Dimond (1957). It must be emphasized that many environmental factors, such as insufficient light, high humidity, excessive nitrogen fertilization, and excessively deep sowing, may cause a decrease in the level of carbohydrates in host plant tissues, contributing to an increase in plant sensitivity to fungal infection (Vidhyasekaran 1974a, 1974b, Morkunas et al 2004, Huber and Thompson 2007, Yoshida et al 2008, Morkunas et al 2010, Morkunas et al 2012. By contrast, low temperature can induce plant resistance to specific pathogens, because it results in accumulation of soluble carbohydrates, affecting the cell water potential and other osmotically-active molecules, as well as accumulation of pathogenesis-related (PR) proteins (Tronsmo 1993, Thomashow 1998, Hiilovaara-Teijo et al 1999, Płażek and αur 2003, Yuanyuan et al 2009).…”