Fresh produce workers in South Africa are to be given greater protection from workplace abuse after a major funding boost.

UK trade body the Ethical Trading Initiative (ETI) has been awarded £300,000 by Comic Relief to help prevent bullying, discrimination and sexual harassment of workers on fruit and vegetable farms and vineyards.

The funding will allow the ETI to provide training materials and send staff to farms to help workplace supervisors develop anti-harassment procedures and teach them how to deal with HR issues. "These supervisors are the people who manage workers on a daily basis, and yet often lack the skills to do so most don't even see themselves as managers," said an ETI spokeswoman.

The three-year project aims to give retailers who are ETI members and source fresh produce from South Africa greater peace of mind that suppliers are acting responsibly.

M&S, Tesco and The Co-operative Group have all helped to develop the training materials.

The agricultural industry represented a huge challenge in terms of worker abuse, and South Africa was a key strategic sourcing market for ETI retailer members, said the spokeswoman. Citrus fruits, avocados, flowers, apples, plums and grapes are among the products sourced from the region and sold by British retailers.

A blueprint for the South African training programme has already been trialled with suppliers in Kenya and the UK, and will be rolled out to South Africa from June next year. The ETI estimates that up to 5,000 workers on 150 farms will benefit.

Marks & Spencer said it welcomed the funding as supervisors had a significant role to play in achieving good labour standards in the supply chain.

"Marks & Spencer and our suppliers trialled the training in the UK and Kenya in a range of sectors and found it to be effective and motivational for both management and supervisors," said Louise Nicholls, the retailer's head of responsible sourcing.