9) Climate change making chickpea susceptible to new diseases

If you think that climate change is merely a drastic change in weather, think again. Scientists at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) found that higher temperatures are making chickpea susceptible to new diseases.

Recent studies by ICRISAT in India indicated that drought caused by prolonged high temperatures increase the vulnerability of chickpea (channa in Hindi) to dry root rot caused by a fungus known as Rhizoctonia bataticola. Dry root rot is one of the two diseases that affect chickpea production; the other is Fusarium wilt.

Commending the findings, Director General of ICRISAT, Dr William Dar said, “The revelation fortifies ICRISAT’s stand that climate change has far reaching impact on food security and the lives of the poorest of the poor. It also reminds us of our responsibility to further study the behavior of pathogens at different levels of temperature and soil moisture.”

Chickpea is a major food legume grown mostly by the poor and subsistence farmers in the semi-arid tropics of Asia and Africa. The studies indicated that under the emerging climate change, high temperature and the resultant rapid soil moisture deficit at reproductive growth stages predisposes chickpea to outbreaks of dry root rot.

There are substantial sources of resistance to Fusarium wilt for chickpea, but none against dry root rot, but dry root rot symptoms can easily be mistaken for Fusarium wilt. The confusion leads to questions about why Fusarium wilt resistant chickpeas are dying? Is Fusarium wilt resistance breaking? And whether a new disease has emerged?

Studying data from 2005 to 2010 during the postrainy season in India, scientists found that there is higher incidence of dry root rot in Fusarium wilt resistant chickpeas in the years when temperatures are over 330C.

Research under different soil moisture and temperature levels revealed that the pathogen infected chickpea plants and manifested dry root rot faster at 350C with soil moisture levels less than or equal to 60%. Fusarium wilt occurs at temperature 250C and soil moisture levels more than 60%.

ICRISAT’s studies clearly demonstrate the combined role of drought plus pathogen (Rhizoctonia bataticola) responsible for dry root rot infection and development.

For more information contact: Dr Suresh Pande at s.pande@cgiar.org or Dr Mamta Sharma at mamta.sharma@cgiar.org.

© by ICRISAT. All rights reserved.