The great camellia fightback
A fungal invader is making a serious dent in the quality of their blooms but camellia fanciers are fighting back.
About 40 per cent of entries at the national camellia show in New Plymouth on Saturday were showing signs of the brown spots caused by petal blight, a fungal disease.
This, along with the ravages of recent very wet weather and the ever advancing age of regular competitors, made it a fairly small show, New Zealand Camellia Society president and show organiser Tony Barnes said.
Many of the flowers with brown spots were clear of them when they were put out for judging, Barnes said. ‘‘That’s how fast it develops. ‘‘The Camellia Society has spent a couple of hundred thousand dollars on research with Massey PhD students to try to find a cure,’’ Barnes said.
Their allies in the quest have names like Sweet Jane, and Sugar and Spice.
‘‘Some of these smaller species camellias are resistant to it; what we have to do is breed another round of new resistant varieties,’’ he said.
‘‘Then we will have to develop some new hybrids to increase the range of colour and flower size. It’s a long-term project.’’ The camellias are also getting help from a Russian PhD student, Nikolai Kondratev, who spoke about his research after the show.
‘‘He’s doing ground-breaking work on the interaction between the fungi and their host. He’s working at molecular level on RNA and DNA to isolate which gene is responsible for resisting the blight,’’ Barnes said.
In most varieties, the blight produced an enzyme that ‘‘tricked’’ the plant into killing cells in its healthy flowers in self defence, which caused the brown patches and provided nourishment for the fungus which feeds on dead plant tissue. ‘‘It’s certainly showing promise in our understanding of how the fungus attacks the plant and why some species resist it,’’ Barnes said.