NZ: Progress made in red kiwifruit breeding program

A new red kiwifruit with a unique taste could finally be commercially grown in a matter of years, after Psa severely impacted the Zespri Plant and Food Research red kiwifruit breeding programme. Since the Psa outbreak in New Zealand, breeders have made significant progress in developing Psa-tolerant red kiwifruit cultivars, and these have reached advanced stages in the cultivar testing programme.

"When Psa first hit New Zealand in 2010 we were close to releasing a red kiwifruit product that we thought was very exciting," Zespri Operations Manager for kiwifruit new cultivar development Bryan Parkes said. "But it turned out the genetics of red kiwifruit is very susceptible to Psa. Psa reset the programme when 80 per cent of our red elite plant material died as a consequence of the Psa outbreak. We have been working to develop Psa tolerant breeding lines and individuals from the remaining 20 per cent that were left alive, and building the red program up again."

Mr Parkes says the new product, which is yet to be specifically chosen or named, needs to provide something different for the consumer. Research will be undertaken around New Zealand and internationally to find the desired flavour for a red kiwifruit to guide cultivar development.

"From a marketing perspective we don't want to just sell a red kiwifruit product that only differs in colour but tastes the same as other kiwifruit in the Zespri portfolio," Mr Parkes said. "Each red cultivar is not the same flavour; there are a vast range of flavours that we can select from amongst the red kiwifruit cultivars in the programme. So we can have reds that taste like gold fruit. But we are looking for something different, generally something that the consumer expects to see in a red kiwifruit, which is usually a berry or a jam flavour. But we also get tamarillo and melon and tropical flavours. We will select something which has a different flavour, but also very desired by the consumer."

The red breeding program has been running since 2000, with wild kiwifruit that were naturally red providing the parents for future generations. Four generations on from that material has produced around 25,000 seedlings, which is then screened for what individual plants show promising signs for the next stage. The top selections are identified and tested in different environments. The final stage is pre-commercial trials, over 40 growers in quarter hectare blocks. Mr Parkes says the selection of new Zespri cultivars is very consumer driven, but has to also meet the needs of the growers and the supply chain.

"We have to look at the product from a consumer’s perspective, so taste is number one followed by convenience" he said. "Then the health proposition is important, because kiwifruit is such a healthy fruit and our consumers are looking for what health properties the new kiwifruit will have. The red variety also has to be exceptionally red to be red in the eyes of the consumer."

Just as important are the agronomic considerations, such as disease resistance and production efficiency.

"It does need to stay alive and with Psa around that is something that cannot be taken for granted," Mr Parkes said. "The team at Plant and Food Research screen all the different seedlings and cultivar selections to see if they are sufficiently tolerant to Psa and commercially viable. Then we have to look at growth rate and productivity, as well as other disease issues that it may have. Ultimately we ask, does the consumer desire the product and can we deliver a quality product through the supply chain?"

Although the new red varieties under development come from the same program as the SunGold, Mr Parkes says due to the characteristics of the red kiwifruit, it is not expected to have as big of an impact as its predecessor.

"Over the 25 year PVR life of Zespri SunGold we will probably generate about $40billion in sales, and will create about 29,000 jobs in New Zealand from this one variety" he said. "Will the Zespri red variety be as successful as that? My guess is probably not, because the storage life of a red cultivar is a bit shorter than Zespri SunGold, so we can't have that product in the market as long. Therefore we are less likely to sell the same volume of Zespri red kiwifruit as Zespri SunGold. But it's hard to predict what premium consumers are prepared to pay for an amazing tasting red. In saying that Zespri SunGold has created eye-watering results and even if we achieve 30 per cent of that it's still a huge success."

Zespri says a lot of research and monitoring still needs to be conducted, so it is difficult to predict the time to market for a new Zespri red product.

"You have to make sure everything is perfect with the cultivar, and if there is any fatal flaw then you really have to go back to the beginning," Mr Parkes said. "But we have got a number of boats in the race, we had a few sink when Psa came along, but hopefully we will get one over the finish line in the next few years."