Photo of Maori potato’s (Taewa), (Science learning hub, 2016, 2018)
Above left: Psyllids (University of California riverside, center for invasive species research, 2020)
Above right : Zebra chip disease (Plant and food research, 2013)
Pesky insects create problems in the potato field :
- Worldwide potato/tomato psyllid’s have become a problem to crop growers. The psyllid is a small insect that carries bacteria causing zebra chip disease. This disease causes discoloured leaves and stunted plant growth as well as less crop return. It also affects the flesh inside the potato during the growing stage, this is not noticed until the potatoes for e.g. are turned into potato chips where the discolouration becomes more obvious.
And the research begins:
- Plant and food research in New Zealand are doing research to find out if Maori potato’s (Taewa) are resistant to the disease. The potato’s are not commercially grown in New Zealand and are often grown by Maori in isolated areas, such as “their gardens,” (Science learning hub, 2016, 2018), these potatoes may hold the key to making commercial variety’s more resistant to zebra chip disease, if resistant varieties can be found they may be able to cross bred these, and make commercial varieties more resistant. This could mean they may be able to use fewer insecticides to control the disease, which growers favour as they “want a more economic and environmentally friendly option” (Science learning hub, 2016, 2018).
- The trial’s that were conducted in 2015 showed that “a full or low insecticide spray does not fully protect against the tomato/potato psyllid” (Science learning hub, 2016, 2018). They also found that the disease when they done the trials was present in “some of the north island” (Science learning hub, 2016, 2018) varieties but, “was not found in any of the south island” (Science learning hub, 2016, 2018) varieties.
More experimentation needs to be done:
- Possibly a useful way to help control the potato psyllid’s would be to introduce Predator bugs such as “damsel bugs and minute pirate bugs” (Colorado state university extension 1998, 09, updated 2019, 01) as they are a natural predator to psyllid’s. Another option could be to grow the potato’s in the south island as the “psyllids do not survive outdoors in areas with severe cold winters” (Colorado state university extension 1998, 09, updated 2019, 01). A good method of detection to see if the psyllids are present might be to plant some pepper plants amongst the potato crops as “the nymphs are often more easily observed on the smooth leaves of the pepper’s” (Colorado state university extension 1998,09,updated 2019,01).
Ways Matauranga Maori can contribute to sustainability goals:
- Quality Education= whakapapa used a moon phase calendar to garden with as they believed that they got better crop return from this could be applied to modern day farming.
- Industry Innovation and Infrastructure= they may be able to use the ideas of kaitiakitanga and use a more traditional way of fertilizing crops by using ash like whakapapa would have many years ago, therefore reducing the nitrates being applied to the soil.
- Economic growth= Scientists could work with Kaitiaki (e.g. Maori elder’s) to establish crops on a Marae and create work for people in the local area by selling the produce as well as having a science research project in place.
Works cited list:
1. Butler,Casey,Trumble, John, Lewis, Mike, Brown Jr,William M (2020), University of California riverside, center for invasive species research, “Potato Psyllid”, accessed on 6/05/2020.
https://cisr.ucr.edu/invasive-species/potato-psyllid
2. Colorado state university extension (1998, 09, updated 2019, 01), “Potato or Tomato Psyllids-5.540”, accessed on 05/05/2020.
https://extension.colostate.edu/topic-areas/insects/potato-or-tomato-psyllids-5-540/
3. Plant and food research (2013) “Maintaining quality in the wake of a pest”, accessed on 6/05/2020.
4. Science learning hub(2016,02,23, updated,2018,03,11), “Taewa and psyllid resistance”, accessed on 05/05/2020
https://www.sciencelearn.org.nz/resources/1067-taewa-and-psyllid-resistance