New research shows kūmara under threat from climate change

New research shows climate change is threatening one of New Zealand's favourite vegetables.

Peruvian researchers tested nearly 2000 strains of kūmara worldwide and found just 6.7 percent were heat tolerant, raising concerns for growers of the sweet potato in the face of global warming.

"Heat and drought stresses are among the most important climatic events aggravated by climate change that affect sweet potato productivity," the researchers wrote.

"The increase in intensity and frequency of heatwaves represents a serious threat to crop production worldwide."

Dargaville kūmara farmer Grant Suckling said growers had no choice but to "be resilient and prepared" as the effects of climate change become more apparent.

"We just have to be prepared for what's going to be thrown at us and we've been given plenty of experience over the previous years, right back to Cyclone Bola," Suckling told The Am Show on Tuesday.

"We've got to be resilient and prepared."

He said, "extreme events are always our concern" but when those weather events last for longer periods of time, it makes growing even more difficult.

"When we get a really, really wet season, if it's at the end of our season and harvest, that can be probably one of the biggest damaging parts of growing kūmara.

"Prolonged dry periods will decrease the amount of product grown and give us good shape which is not too bad for us all but it does increase the price, because of supply and demand."

Suckling said kūmara growers had invested a lot in recent years into automation technology and also to be able to have more staff on board "so we can actually get our crop out when the conditions are better".

And while that investment may make some things easier, growers had to be prepared for all sorts of weather conditions, he said.

"I suppose we've never not had extreme conditions here in New Zealand, that's the reality of it."