New field trials to help identify the cause of yellowing cane commence

22 April 2013
Two new field trials conducted by leading scientists from BSES Limited (BSES) will commence in Tully and the Mulgrave area as part of the ongoing investigation into the cause of yellowing cane.

Dr Andrew Ward, Manager Professional Communication and Extension Unit, BSES said that these  trials are part of a structured and rigorous approach being followed to accurately identify the  condition.

“To date our thorough investigations of affected fields have failed to identify any potential causal  agent that is common to all fields and there are no obvious conclusions as to what is causing the  yellowing. As such, the next step is to investigate the cause or causes of the problem in a systematic  and controlled manner with field trials and laboratory trials,” said Dr Ward.

“With planting season upon us local productivity service boards are being asked by growers whether  the yellowing disorder can be transmitted via planting material.

“At this stage, we don’t believe that the yellowing is caused by a systemic disorder but this has not  conclusively been ruled out. In an attempt to rule this out a trial will be established in Tully this  week under controlled conditions.

“Until the results of this trial are known we recommend that growers stick to the basic principle of  using the best quality planting material that they have. Cane that is severely affected and not  growing actively is unlikely to germinate well and establish vigorously so should be avoided.”

The second trial which will be established in the Mulgrave region aims to rule out linear bugs as a  cause of the yellowing.

“We are investigating all possibilities and one of our leading entomologists will conduct a trial,” he  said.

Cane crops showing yellowing symptoms in the Burdekin were visited on April 17 by a working group  that included a broad-knowledge research team from BSES, growers and representatives from the  Burdekin Productivity Services Limited; Herbert Cane Productivity Services Limited; and the Sugar  Research Development Corporation.

“This group included the industry’s most experienced plant pathologists, entomologists, agronomists  and crop nutrition experts who have a combined knowledge base built from over 200 years’  experience in sugarcane research,” said Dr Ward.

“The group agreed that some crops which are healthy and have been grown using best management  practices are likely to have excellent yield, even though they have some yellowing. On the other  hand, other crops which were not so well maintained are likely to yield less due to their poor  condition, regardless of the yellowing.”

Following the tour, the working group wanted to reassure industry that all steps are being taken to  diagnose the condition.

“A correct diagnosis is vital to understand the cause of the yellowing and finding a solution for growers that will work. This will take time, as we saw some years ago when Northern Poor root  syndrome was first identified. In this situation it was several years before Pachymetra root rot was  identified as the causal agent,” said Dr Ward.

“A rushed diagnosis runs the risk of being wrong and this outcome could potentially waste growers’  time and money.”

The trials are expected to be completed over the coming weeks.

A newsletter about the yellow cane situation can be accessed by selecting Subscribe to Updates on the homepage of the BSES website http://www.bses.com.au/