“The Group would require someone with experience and exposure to direct its growth amidst the challenges of the global economy,” the board of Tata Sons Ltd., which controls the Tata Group companies, said in a statement.

The salt-to-SUV conglomerate, founded in 1868, is one of India’s most successful family dynasties.

Its holdings include Tata Motors, the creator of the supercheap Nano car, and Tata Consultancy Services, India’s largest outsourcing company. It also owns Jaguar Land Rover and Corus Steel, making it the UK’s biggest manufacturing employer.

The board said it would consider candidates from within the Tata companies, as well as other Indian and foreign professionals.

Local speculation — which the company dismisses — has long centered on Noel Tata, Ratan Tata’s reclusive half brother as heir to the empire.

Noel Tata quietly served for years as head of the group’s small retail division, Trent. Last week he was appointed head of Tata International, the group’s unlisted international trading division, which deals in things like steel, leather and iron.

In fiscal year 2009, Tata Group revenues totaled $70.9 billion, two-thirds of which came from overseas. The group’s 28 listed companies have a market capitalization of around $60 billion.

Since he took over as chairman in 1991, Ratan Tata, who serves on the boards of Fiat SpA and Alcoa, has boosted group revenues nearly 12-fold.