Morphological variability of Botrytis cinerea – causal agent of Japanese quince grey mould

I. Jakobija¹²*, B. Bankina¹ and A. Klūga¹²

¹Latvia University of Life Sciences and Technologies, Liela iela 2, LV–3001 Jelgava, Latvia
²Latvia University of Life Sciences and Technologies, Institute for Plant Protection Research, Paula Lejina iela2, LV–3001 Jelgava, Latvia
*Correspondence: inta.jakobija@llu.lv

Abstract:

Botrytis cinerea is a causal agent of grey mould that damages many species of plants including Japanese quince (Chaenomeles japonica (Thumb.) Lindley ex Spach). Grey mould has been found on Chaenomeles spp. flowers, fruits in all stages as well as on twigs. Morphological variability within Botrytis species has been previously reported in the literature, but no information is available about B. cinerea isolated from Chaenomeles spp. The aim of this study was to describe the symptoms of grey mould and clarify the morphological variability of B. cinerea isolates obtained from samples collected in commercial plantations of Japanese quince. Samples of plant parts with different fungal disease symptoms were collected in eight commercial plantations of Japanese quince during vegetation seasons of 2017 and 2018. Some samples were taken in Japanese quince plantations in Lithuania and Estonia. A total of 286 isolates of fungi were isolated from damaged shoots, leaves and fruits of Japanese quince plants, using potato dextrose agar. Botrytis cinerea isolates (39) were separated depending on the morphological characteristics and were proved by using methods of molecular biology. B. cinerea was isolated from shoots, leaves and fruits. The isolates of B. cinerea were described and classified into distinct morphological types depending on the characteristics of mycelia, sclerotia, reverse side of media and the presence or absence of sporulation.

Key words:

Chaenomeles spp., fruit rot, morphological type, sclerotia, sporulation

Effect of environmental conditions and inocolum concentration on sporulation of Peronospora destructor

V. Bulovienė and E. Survilienė

Lithuanian Institute of Horticulture, Kauno str. 30, LT - 54333 Babtai, Kaunas distr.,Lithuania; e-mail: v.bandzeviciute@lsdi.lt

Abstract:

The effect of inoculum concentration, incubation time, relative humidity (RH) and temperature on sporulation of Peronospora destructor on onion leaves was analyzed under controlled environmental conditions in a greenhouse. The shortest period for spore germination and sporulation was on onion leaves inoculated with 106 spores/ml distilled water suspension. The intensity of infection and the sporulation of infected plants were affected greatly by the time and temperature of incubation. Exposure of inoculated plants at 15°C for 8 days and then at 22°C for 5 days resulted in the percentage of infection and the most abundant sporulation. Results of this experiment indicated that the period of P. destructor sporulation on one plant lasted 4–8 days.

Key words: