Ground Cover North : GroundCover 129 July-August 2017 - North
By Nicole Baxter n Effective weed management is a high priority for Keith Lord and his family in their drive to build a profitable and resilient farm business near Junee in southern NSW. With his wife Debra, sons Gregory and Andrew and assistant manager Jeffrey Breading, Keith has employed multiple weed-management tactics to manage herbicide resistance on the 2068 hectares of land under his care. Narrow windrow burning is the most recent tool added to the armoury against weeds. "Although we don't have a major problem with herbicide resistance, we have developed a blanket policy of narrow windrow burning our canola stubbles every year," Keith says. "It has kept weed numbers low and our four-year pasture phase is useful for cleaning up annual ryegrass. We try to hit weeds from every angle." Twice yearly, the Lords meet their agronomist -- Tim Condon from Delta Agribusiness -- to discuss rotation plans and refine weed management according to seasonal conditions. Generally, a pasture mix of lucerne, subclover, arrowleaf clover and chicory is undersown with the final crop of a canola/wheat/canola/wheat/canola/wheat or barley sequence. The pastures are grazed for two years before management of annual weeds starts with winter cleaning and spray fallowing in the two years before cropping. Keith likes to grow Clearfield® and triazine-tolerant canola varieties so different herbicide groups can be rotated. Faba beans have been tried to add diversity to the rotation, but Keith says he is finding them difficult to justify because of low prices. Nonetheless, the crop's sensitivity to acid soils has proved a valuable pointer to a problem that until recently had gone undetected -- stratified pH in the top 20 centimetres of soil. "Faba beans have been like a canary in a coalmine to us, alerting us to an issue we didn't know was throttling our grain yields and profits," Keith says. Although traditional composite zero to 10cm soil tests indicated the pH was adequate, faba beans in some parts of the paddock had failed to nodulate. Keith and Tim did not know why until Helen Burns, a pasture development officer at the NSW Department of Primary Industries, found the roots had hit a very acidic layer (pH of less than 4.5 in calcium chloride) at 5cm. To address the problem, Keith now applies higher rates of lime and mixes it through the topsoil with a scarifier fitted with sweep points. Keith is working with Ms Burns and NSW DPI senior research scientist Dr Mark Norton on a GRDC-supported project to monitor the impact of lime rate and application method on soil pH and subsequent crops. o Feature: Page 13 "IT HAS KEPT WEED NUMBERS LOW AND OUR FOUR YEAR PASTURE PHASE IS USEFUL FOR CLEANING UP ANNUAL RYEGRASS. WE TRY TO HIT WEEDS FROM EVERY ANGLE." KEITH LORD Weed strategy invests optimism into the future PHOTO: NICOLE BAXTER By Jo Fulwood The design of a new barley variety that can better handle heat, frost, drought, pests and diseases has been brought considerably closer by an international genetics research collaboration. Scientists from 10 countries have unravelled the genetic secrets of the barley plant, allowing them to understand which genes control barley's ability to adapt to a wide range of climatic challenges and environmental stresses. Western Barley Genetics Alliance director Professor Chengdao Li says the map of the barley genome will allow breeders and pre-breeders to develop molecular markers for the development of new barley varieties -- something until now largely thwarted by the size of the barley genome. "Barley has a large and complex genome, with 5.1 billion genetic letters assembled into seven chromosomes," Professor Li says. "This research was so large and complex that no single country had the capacity, so an international collaboration was essential." He says the genome map will give barley breeders and researchers confidence to manipulate relevant genes and reduce the time taken to develop new high-performance barley varieties tailored to Australian environments. The genome mapping clears the first hurdle GENETIC MAP POINTS THE WAY TO ADVANCED NEW BARLEY in variety development, which will now require extensive phenotyping (connecting genetics with environmental influences and performance). Eighty per cent of Australia's malting barley is exported, but fluctuating supply has led to increased competition from Europe and Canada. Professor Li says drought, heat, frost and disease mean Australia's annual barley production has varied from four to 13 million tonnes over the past decade. "Mapping the barley genome will provide an efficient tool to identify key genes controlling these traits and thus develop new barley varieties to tolerate these stresses." He says increased global competition has also recently come from the former Black Sea states and South American countries, which have lower production costs and/or freight advantages. "Australian barley not only needs to match the malting quality improvements of European and Canadian varieties, but we also have to improve productivity," he says. The Western Barley Genetics Alliance worked with scientists from Germany, the UK, the US, Finland, Denmark, China, the Czech Republic, Sweden and Switzerland. o GRDC Research Code DAW00233 More information: Professor Chengdao Li, 08 9368 3843 REGIONAL EXTENSION REPORT PAGES 41 TO 43 WITH THIS ISSUE 24 PAGE SUPPLEMENT Integrating livestock and cropping systems ISSUE 129 | July -- August 2017 Keith Lord (centre) with son Gregory (left) and assistant manager Jeffrey Breading (right) burning narrow windrows made from canola stubble.
GroundCover 128 May-June 2017 - North