Papers presented by researchers at the recent round of Grains Research and Development Corporation (GRDC) crop updates, reported considerable progress in chickpea breeding for improved cold tolerance, disease resistance and yield of future varieties.
Improved disease management via fungicide use was also highlighted.
Cold spells in late winter and spring are often a big issue for chickpeas.
Mean day temperatures of 15 degrees or lower cause flower sterility and poor pod set.
All too commonly, late cold spells set crops back enormously and result in flowering to pod fill being delayed, compared to when conditions are much warmer.
Improved cold tolerance would allow earlier successful flowering and pod development with potentially higher yields.
Research led by NSW Department of Primary Industries (DPI) Tamworth's Neroli Graham, indicates improved cold tolerance has the potential to lift yields, but the potential benefit has yet to be determined.
Currently, cool spells after temperatures have begun to rise interrupt flowering and seed set and reduce yield potential.
Pre-breeding investigations in Western Australia have found one especially promising wild relative of chickpea, that has shown more than six times greater pod numbers under cold temperatures, than current NSW varieties.
It is hoped that this can be used in the breeding program to improve future varieties.
Other crosses with wild types with improved cold tolerance are being assessed.
Experimental chickpea lines with improved phytophthora root rot resistance - a major disease risk after high rain events, especially on heavy poorer drained soils - have also been identified.
Even with the most resistant current variety (MR rating) yield losses have been more than 40 per cent.
Pre-breeding investigations in Western Australia have found one especially promising wild relative of chickpea, that has shown more than six times greater pod numbers under cold temperatures, than current NSW varieties.
- Bob Freebairn
Research led by NSW DPI agronomist Sean Bithell has noted yield losses from the most promising breeding lines lose very little yield under high phytophthora conditions.
In contrast current varieties lost 40 to 70 per cent yield.
Experimental lines with improved phytophthora resistance have also yielded competitively, with current varieties in nil or low phytophthora disease situations.
A couple of these lines are being considered for commercial release.
Current NSW DPI advice is to avoid chickpeas in paddocks prone to waterlogging or poor drainage.
Also avoid areas with a history of lucerne, medics or past disease affected chickpeas, as these paddocks favour phytophthora root rot.
NSW DPI plant pathologist, Dr Kevin Moore, leads another important program investigating best fungicide management of ascochyta blight, a disease also capable of decimating chickpea yields.
While sowing varieties with the best resistance rating is an important part of management, ascochyta outbreaks still cause major yield losses.
Dr Moore and colleagues research finding stresses the importance of treating sowing seed with appropriate fungicide and continue to apply fungicides, chlorothalonil and mancozeb, ahead of rainfall events.
Research has shown these products are rain fast even with heavy rain events and protect existing vegetation from ascochyta blight.
As these products are protectants only, they are not effective applied post rain to limit fungal infections in chickpea crops.
If a pre-rainfall event is missed for fungicide treatment, Dr Moore and colleagues' research has shown that new chemistry and formulations offer the possibility of limited salvage fungicide sprays for ascochyta control, if applied soon after rainfall (infection) events.
Dr Moore stresses that pre-rainfall applications with appropriate fungicides remains the most effective option.
All these programs involve GRDC and NSW DPI funding as well as interstate collaborations.
Full details of the papers are available from proceeding of the 2019 GRDC Dubbo and Goondiwindi updates, as well as on the GRDC website.
Next week: Grazing management to hasten drought recovery.
- Bob Freebairn is an agricultural consultant based at Coonabarabran. Email robert.freebairn@bigpond.com or contact (0428) 752 149.