Lentils instead of lupins? Trials underway in Merredin to grow lentils in higher pH soils across Wheatbelt

Vast tracts of WA land could be opened up to “hardy, high-value” lentil crops over low-value lupins if a genetic acid tolerance study in the central Wheatbelt proves successful. Traditionally grown on the more alkaline, sandy soils of the Esperance region, researchers are hoping to identify genetic lines which can handle the more acidic soils further north. With prices hovering around $600/t to $700/t and production across Australia booming — with 780,000 tonnes harvested in 2021, up from 360,000 tonnes in 2018 — researchers are hoping more growers can add the pulse to their “toolkit”. Paddock preparations are underway at the Department of Primary Industries and Regional Development’s Merredin Dryland Research Facility, with strips of fine lime applied to increase the pH of the soil from five to six. It is one of several genetic projects across wheat, lentils, canola and barley being run by the Department’s genetic improvement group at the Merredin site in collaboration with universities and industry organisations. DPIRD research scientist Rosemary Smith said the project would screen 48 lines of lentils — as well as two field pea lines — for lower pH tolerance. “They’ve got quite a specific niche in where they grow,” she said. “The site here has a pH of five, which is slightly outside the lentil desirable soil range. “What we’ve done is set up a site where we’ve created lime strips... and next year, the lentils will be grown in both ameliorated and non-ameliorated strips. “We’re not trying to get a lentil that grows in pH three. We’re just trying to increase the area that lentils might be able to grow.” It is being held across two sites to test the impact of rainfall, with the Merredin site averaging 300mm a year and a site in Shackleton averaging 350mm. The trial forms part of two national five-year lentil breeding and selection projects with Grains Research and Development Corporation and Agriculture Victoria. Lentils are successfully grown in Australia’s southern, medium-rainfall cropping zones and it is hoped varieties which can be grown in the hotter, drier and more acidic Wheatbelt, Mallee (Victoria) and northern NSW regions can be identified. GRDC oilseeds and pulses manager Dr Francis Ogbonnaya said while some regions across Australia had been able to incorporate lentils into their systems and turn good profits, farmers in other parts of the country were “missing out”. “This new GRDC investment is to boost the pre-breeding programs of lentils to expand their geographical range and to ensure that in every part of the country there will now be a lentil variety that suits those conditions and can grow well in a crop rotation system, expanding the options to growers for legumes they can use,” he said. Australia is the second biggest exporter of lentils, exporting $535 million in 2020 and accounting for 13.3 per cent of world trade behind Canada, which accounts for more than half. Agriculture Victoria researcher Garry Rosewarne said they had become “much more than just another legume” to put nitrogen back into the soil. “Lentils are where the money is and we now have some farmers growing them year on year as their main crop,” he said. Mrs Smith believed there would be a swing from lupins to lentils if the study — which aims to have commercial varieties available down the track — was successful. “A lot of the growers here grow lupins and prices have remained low, so they’re actually making a loss on them,” she said. “This year they’ve pulled a lot of them out and replaced them with canola, chasing the higher prices.” On top of the two trial sites being prepared for 2023 sowing, Mrs Smith said they had this year sown lentils with the same genetics as the upcoming trial on a paddock in Merredin with a slightly higher pH. As inputs skyrocket, she said lentils would become a more attractive option for growers. “While fertiliser prices are high, growers are looking for something to add into their rotation which adds nutrition and can also get better prices and yields,” Mrs Smith said. “They might end up with 500 tonnes of lentils instead of 340 tonnes of lupins.”