Kolkata, March 1: Former President Pranab Mukherjee on Wednesday said the country has to overcome challenges in agriculture, employment and power to become a sustainable economy with a substantial growth rate. Claiming that the economy has the potential of growing at a rate of eight to nine per cent every year, Mukherjee urged the current government to work towards addressing not just the major challenges but also the related issues through "cooperative federalism". "By 2025, India would become a $5 trillion economy from $2.224 trillion now. But it would only be possible if all the points of deficiency are adequately addressed," Mukherjee said while addressing a session on prospects of economic growth in India organised by the Calcutta Chamber of Commerce here. "Hungry people, malnutritioned children, unemployed youth -- these three are the major challenges in the country. Also, the power generation and its impact on the environment has to be monitored." Hailing India's growth in the agricultural sector, Mukherjee said the government should keep working to protect the sector to feed a huge and growing population. "We must protect the agricultural sector. There is no room for complacency. We might take pride in the fact that India has become a great exporter of food grains. But we should not forget that ours is a growing population. "India's current population is 1.32 billion that would grow at a fast pace. Therefore this growing population needs to be fed. "But when we talk about agriculture, it is not just the production of the food grains alone. Rural infrastructure, irrigation, rural health, education, sanitation and housing should also be developed," he pointed out. He said the success of the Indian economy would heavily depend on its ability to train and skill the large number of youths and get them ready for the world market. "India has the youngest population in the world but unless we train them, give them employment, enhance their expertise and make them available for the market in the world... "It is the biggest challenge for our government to ensure how quickly we can skill and train our young generations," he added.