Scientists decode impact of El Nino on crop production

Syed Akbar
Hyderabad:  City scientists have decoded the impact of El
Nino phenomenon on the overall farm productivity in Andhra Pradesh. El
Nino is a pervasive climatic event that triggers changes in climate at
regional level primarily affecting agricultural production.

In a first of its kind study on the El Nino effect on Indian
agriculture, a team of researchers from the city-based Central
Research Institute for Dryland Agriculture (Crida) has found that El
Nino is more pronounced in Rayalaseema compared to
Telangana followed by coastal Andhra. Districts like Anantapur and
Kurnool experience negative departure in average southwest monsoon
rainfall by more than 20 per cent.

The team comprised VUM Rao, AVM Subba Rao, B Bapuji Rao, BV Ramana
Rao, C Sravani and B Venkateswarlu. According to Crida scientists, the
performance of southwest monsoon in the country has a tele link with
El Nino phenomenon. They analysed long-term data and found an inverse
relationship between El Nino and southwest monsoon rainfall in India.
The research study included the impact on the productivity of crops
like rice, groundnut, castor, pigeonpea, chickpea and pearl millet.

The average southwest monsoon rainfall received during the years with El Nino
was found to be less compared to normal years and the average rainfall
during the northeast monsoon is higher in coastal Andhra. Either the
southwest monsoon rainfall or the annual rainfall will be less during
the years with El Nino.

Barring SPS Nellore district, the average total food grain production
throughout
the State declined during El Nino years. The decrease in production
was more than 10 per cent in several districts. Anantapur recorded 10
per cent fall in groundnut production. During kharif season, there was
a decline in average production of rice by 12 per cent in the State.
When the total food grain production excluding rice was examined, the
decline in production and productivity appeared to be more than 25 per
cent.

The Crida study suggested inter-cropping systems with long duration
base crop and short duration inter-crop in traditional rain-fed
mono-cropping areas, and increase in productivity of rabi crops by
judicious use of fertilizers and adoption of pest and disease control
during the early stages of its growth. It also recommended system of
rice intensification (SRI) during Khariff in case of El Nino, and
moisture conservation practices for mango, cashew and coconut to
increase their yields.