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

Efficacy of seed treaters on the germination of ergot (Claviceps purpurea (Fr.) Tul.) sclerotia and stroma formation

R. Mikaliūnaitė and Z. Dabkevičius

Šiauliai University, Višinskio 19, Šiauliai, 77156, Lithuania; e-mail: OIKOS@fm.su.lt

Abstract:

The effects of the fungicidal seed treaters Baitan-Universal 19,5 WS and Divident Star 036 FS, Divident Star with bioactivator Penergetic-p and Penac as well as biopesticide Bionature R2000 applied alone on the germination of ergot (Claviceps purpurea (Fr.) Tul.) sclerotia and stroma formation were studied in the laboratory and field conditions in 2004 and 2005. Rye (Secale cereale L.) seed, contaminated with ergot sclerotia, was used for the tests. The rates recommended for rye seed treatment were applied.In the experiments 45.5–79.0% of untreated sclerotia germinated, and each sclerotiumformed on average 3.7–7.5 stromas. The fungicidal seed treaters tested inhibited and delayed sclerotia germination. In the laboratory conditions Baitan-Universal and Divident Star gave 86.1-100% suppression of sclerotia germination and 90.1–100% of stroma formation. Under the field conditions this suppression was lower: 46.2–68.8 % and 57.4–84.3%, respectively. Bioactivators did not exert any effect on sclerotia germination and stroma formation in the laboratory conditions, but they increased sclerotia germination by 3.3–15.3% and stroma formation by 19.5–96.0 units per 100 sclerotia in the field conditions. The biopesticide Bionature significantly inhibited stroma formation only in 2005.

Key words: