PHYTOTOXIC ACTIVITY OF TOX0 LEPTOSPHAERIA MACULANS METABOLITES TO MICROSPORE-DERIVED EMBRYOS AND PROTOPLASTS OF OILSEED RAPE
W ZHANG1, P KACHLICKI2, T CEGIELSKA-TARAS3 and M JEDRYCZKA2
1Genetic Engineering Laboratory, College of Biotechnology, South China Agricultural University, Guangzhou, China; 2Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, 60-479 Poznan, Poland; 3Institute of Plant Breeding and Acclimatization, Strzeszynska 36, 60-479 Poznan, Poland
Background and objectives
Several compounds causing necrotic spots on cotyledons or leaves of different plant species (barley, wheat, pea, lupin, beet, oilseed rape) were found in culture filtrates of different Polish Tox0 isolates. For one of these isolates (PL18) the active compound was identified as benzoic acid . A partially purified phytotoxic fraction from the other isolate (PL68) contained large amounts of succinic acid presumed to be the active principle. The objective of this work was to study the interaction of fungal metabolites with different plant tissues grown in vitro.
Materials and methods
Protoplasts were isolated from leaves of 2-month-old plants of rape cv. Leo and grown on semi-solid D2a medium with 0.65 M of glucose, NAA, 6-BA and 2,4,5-T. The purified protoplasts were placed in petri dishes at the final density of 3-5x105 per ml. The petri dishes were incubated in the dark without shaking at 26°C. Compounds tested were dissolved in media of respective cultures, sterilised using Millex filters and added to final concentrations ranging from 0 to 50 mM. Damaged protoplasts were identified by staining with Evans Blue and observation under an inverse microscope.
Results and conclusions
The above results show that in vitro cultures of oilseed rape, including microspore-derived embryos and protoplasts, are useful tools for the bioassay of phytotoxic effects of metabolites from the Tox0 Leptosphaeria maculans isolates.