Leaf spot and dieback of Buxus caused by Cylindrocladium buxicola

Abstract

AbstractŠafránková I., Holková L., Kmoch M. (2013): Leaf spot and dieback of Buxus caused by Cylindrocladium buxicola. Plant Protect. Sci., 49: 165-168.Leaf blight symptoms were observed on potted box plants (Buxus sempervirens cv. Suffruticosa and B. microphylla) in a nursery in South Moravia in August 2010. These symptoms were suggestive of box blight on Buxus spp. Characteristics of the visual symptoms, microscopic features, and identification of the isolates using DNA sequencing are described. The causal agent was isolated and identified as Cylindrocladium buxicola Henricot by means of morphological, cultural, and molecular characters. The effect of five commercial fungicides on C. buxicola in vitro was studied. The most effective fungicides (kresoxim-methyl, azoxystrobin, and mancozeb) inhibited conidia germination and mycelial growth (kresoxim-methyl, myclobutanil, and penconazole) of C. buxicola more than 96%. Keywords: box blight; box; fungicidesIn August 2010, we received ten potted Buxus sempervirens cv. Suffruticosa and B. microphylla plants from a nursery in South Moravia. These plants were affected by disease and exhibited dark spots on the leaves. As a result of the infection, the plants defoliated and dieback ensued. The sporulation covered the abaxial surface of infected leaves and we found two independent pathogens, pink sporodochia of Volutella buxi (DC.) Berk. and fuzzy white spore masses of the second pathogen, which was identified as Cylindrocladium buxicola. V. buxi is usually regarded as a wound pathogen causing dieback on box or considerable damage in nurseries.Box blight, caused by C. buxicola, was reported from Europe and New Zealand in the 1990s (Henricot et al.

Combined Application of Bio-PF and Synthetic Fungicide Suppress Soil Borne Disease Caused by Cylindrocladium sp. in Leather Leaf

“…These conditions inferred that the disease development and spread under UV plastic + 70% shading net shelter was actually inhibited. Additional UV plastic for shelter cover avoided the rain splashing thus reduced the moisture around the plants in which these were considered to be the main pathogen carrier of the disease (Šafránková, Holková, & Kmoch, 2013). Under less rain splashing, the active ingredient of bio-and synthetic fungicides were more persistent on phyllosphere (Suhardi, 2007) and biological adaptation of PF might undergo more optimally, thus supressed the disease effectively (Shternshis, Shpatova, & Belyaev, 2016) than those under 70% black-net shelters.…”