'Eskimo' chickpea comfortable on chilly nights by Eammon Conaghan
GroundCover™ Issue: 43
CAPTURING THAT lucrative but elusive $400 per tonne return for chickpea comes with unique challenges for WA graingrowers.
WA's low overnight inland temperatures interfere with early pod set in chickpea and cut yield by up to 15 per cent, robbing growers of over $60/ha. Attempts to avoid cool conditions during flowering by delaying sowing can push pod fill into the dry weeks of October, where moisture is too scarce to sustain good production.
This double jeopardy has prompted research at WA's Centre for Legumes in Mediterranean Agriculture (CLIMA) to develop more robust varieties that flower earlier and set pods while moisture is abundant. The new varieties will also incorporate better resistance to Ascochyta blight.
"WA is currently planting less than a sixth of the area to chickpea that it could sustain, which represents a lost opportunity given that the crop is our highest-paying pulse, " said CLIMA and University of WA researcher Heather Clarke.
Taking a new approach, CLIMA is developing 'Eskimo varieties' with a better cold tolerance.
How it works
Chickpea sets seed when a tube is sent from the pollen's landing point on the flower's reproductive surface to the egg 10 mm below. However, when the average daily temperature dips below 15°C, these tubes shudder to a stop before reaching the egg.
Working with germplasm from India and Syria, with some existing chilling tolerance, this GRDC-supported project has already developed locally adapted lines which will tolerate average temperatures of 13°C.
"We pollinate plants under controlled low temperature stress and retain only the survivors from generation to generation in the breeding program, " Dr Clarke explained.
"This approach takes much of the guesswork out and helps control other factors such as exposure to light, moisture and humidity, which can interfere with reproduction. "
At this critical level, the extra two degrees in chilling tolerance could result in pods setting two weeks earlier to broaden the planting window for WA growers.
In addition to chilling tolerance, some of the advanced lines are also showing greater tolerance to Ascochyta blight than standard varieties such as Sona and Heera.
While these varieties undergo field evaluation before release to WA growers, Dr Clarke has also developed molecular marker technology to help hasten the ongoing bid to drive the tolerable temperature for chickpea even lower.
Program 2 Crop Improvement Contact: Dr Heather Clarke 08 9380 1648