Key issues impacting on the profitability of lupin growers – including manganese deficiency and establishment rates – are the focus of two new research projects in Western Australia.
Grown across about 350,000 hectares in WA, lupins are the State's most widely grown pulse crop and plantings have increased in the past three years.
New Grains Research and Development Corporation (GRDC) research investments aim to provide lupin growers with information to help them maximise establishment, yields and grain quality, and to reduce the incidence of 'split seed'.
GRDC grower relations manager – west, Curtis Liebeck, said one of the projects was addressing manganese deficiency, an issue that had become more evident in recent years.
"Narrow leaf lupins have a poor ability to translocate manganese from the leaves to the grain, which can result in split seed and yield penalties as high as 70 per cent," Mr Liebeck said.
"Manganese deficiency can be corrected at seeding time with fertilisers that contain manganese or with foliar applications of manganese later in the season."
Mr Liebeck said trials conducted by Crop Circle Consulting would compare different types of foliar-applied manganese fertilisers, as well as application rates and timings, and their impact on manganese concentration in lupin seed and the incidence of split seed.
"The trials are being conducted on grower properties in the Geraldton port zone, with treatments including manganese formulations that are available to growers – including carbonates, chelates and sulphates," he said.
"The two times of application being tested will be prior to pod set and when pods on the primary stem are two-to-three centimetres long.
"By early 2020, the project is expected to generate information that may help growers improve overall manganese concentration in lupin seed and reduce the incidence of split seed."
Mr Liebeck said the second investment was being led by the Liebe Group and was addressing concerns raised about poor establishment of lupin crops, especially in newer varieties.
"Some agronomists and growers believe this could be caused by seed coat damage from machinery and handling techniques," he said.
"Research conducted in the 1990s found harvester drum speed had a negative impact on lupin establishment, but farming systems and techniques have changed since then, and it is thought increased handling of seed may be to blame for current issues.
"Poor establishment is important to address as it has a compounding negative impact on grower profitability, due to the effect on inoculation costs, seeding rates, paddock coverage and weeds, as well as discouraging growers from adopting new, higher yielding varieties."
Mr Liebeck said the new investment would test if lupin establishment rates for different varieties were reduced following a range of handling processes.
"Testing of seed coat integrity will also test if manganese deficiency is affecting seed coat thickness and subsequently lupin crop establishment, following handling," he said.
"The research will also investigate the overall cost to industry caused by decreased lupin establishment."
