Pg. 13-17 Status of the ARC-Institute for Tropical and Subtropical Crops’ Litchi Improvement Programme, as well as the commercialisation process for new cultivars

For many years only two cultivars formed the basis of the South African commercial litchi industry, namely ‘HLH Mauritius’ (Tai So) and ‘McLean’s Red’. The traditional harvest period of South African litchis coincides with the harvest times of countries such as Mauritius, Madagascar, Reunion and Australia, resulting in competition effects. Since 2002, based on results obtained from the Agricultural Research Council-Institute for Tropical and Subtropical Crops’ (ARC-ITSC) litchi evaluation project, ‘Third Month Red’ (TMR) and ‘Wai Chee’ are recommended for extending the early and late season markets respectively. Litchi improvement in South Africa aims to extend the harvesting period even more and at the same time deliver a cultivar of improved quality.

The South African ARC’s Litchi Improvement Programme is based on four phases, these being (1) breeding and selection, (2) description and registration, (3) climatic adaptability assessment and (4) commercialisation. This paper gives a description of the current status of this programme and the commercialisation process of new cultivars.

Summary:

• The South African commercial litchi industry historically depended on two main cultivars: HLH Mauritius Tai So and McLeans Red, facing competition due to overlapping harvest seasons with countries like Mauritius and Australia.
• Since 2002, the ARC-Institute for Tropical and Subtropical Crops (ARC-ITSC) recommended two new cultivars, Third Month Red (early season) and Wai Chee (late season), to extend market availability.
• The ARC-ITSC Litchi Improvement Programme aims to develop cultivars with large fruit size, small seed, good taste, long shelf life, high annual yields, and wind resistance.
• The breeding program started in 1993, involving open and controlled pollinations resulting in over 10,000 seedlings planted across multiple sites for evaluation.
• The program has four phases: breeding and selection; description and registration; climatic adaptability testing; and commercialisation.
• Seedlings are scored on fruit quality criteria, and promising selections are propagated by grafting onto rootstocks for further evaluation and eventual Plant Breeders Rights registration.
• Mid-season, early-season, and late-season selections with improved qualities compared to standard cultivars were identified and are undergoing further evaluation.
• The climatic adaptability phase involves testing new cultivars in different climatic regions through co-operative growers and a cultivar management agent to determine the regional suitability.
• The commercialisation phase focuses on release to industry, establishment of growers clubs to manage cultivar distribution and royalties, and marketing protocols to protect intellectual property.
• The program faces challenges like a long juvenile period for seedlings (5-10 years), slow propagation, and the need for large populations to increase success rates.
• New breeding tools, including cross-pollination, irradiation for mutation, and grafting techniques, are being used to diversify the gene pool and improve success.
• The entire process from breeding to full commercialisation can take approximately 30 years, but existing seedling blocks may shorten this timeline by several years.
• The ARC-ITSC Litchi Improvement Programme is progressively expanding its genetic base and breeding methods, showing promise for consistent release of improved litchi cultivars.