Differential effects of gibberellic acid on the growth of Botrytis cinerea isolated from various ornamental plants

摘要

Various hormones are involved in the growth of Botrytis cinerea Pers.: Fr., and they are generally the same as those found in plants. It has been shown that this fungus produces ethylene and indolacetic acid but, so far, gibberellic acid (GA_3) and abscisic acid production in Botrytis spp. has not been proved unequivocally (Sharon et al., 2004). Although hormones play an essential role in fungal growth, further studies are necessary to understand the pathways of phytohormone biosynthesis in Botrytisspp., their effects on fungal growth, and their interactions with plant growth. GA_3 is a commonly occurring hormone found in plants and some fungi, including Gibberella fujikuroi and Sphaceloma manihoticola. GA_3 promotes cell division and/or cell elongation in plants, and is relatively abundant in juvenile plant tissues. Exogenous application of GA_3 to plants can reduce their susceptibility to infection by Botrytis but, rarely, it has been shown to promote disease (Sharon et al., 2004).