- I.J. Froneman, J. Husselman, S. Rheeder, C.F. Human, and A.D. Sippel
- Institute for Tropical and Subtropical Crops, Private Bag XI 1208, Nelspruit 1200
- 2002
It is well known that a very short litchi marketing season occurs in South Africa due to a- lack of cultivars. This need for cultivars prompted the initiation of a cultivar improvement programme in 1992. The South African litchi improvement programme consists of two interlinked strategies, namely evaluation of imported cultivars and the breeding of new material, adapted to local conditions. The main aims of the programme are to obtain early and late cultivars with improved fruit and tree characteristics. This paper deals with new developments and strategies to improve the efficiency of the improvement programme as well as progress being made. A report on seedling evaluation at the ARC-ITSC is presented. Methods to accelerate the evaluation and distribution of new material throughout the industry are discussed.
Summary:
The South African litchi industry faces a short marketing season primarily due to limited cultivar variety, prompting a cultivar improvement program started in 1992.
The improvement program has two strategies: evaluation of imported cultivars and breeding new cultivars adapted to local conditions aiming for earlier and later ripening varieties with better fruit and tree traits.
Historically, only two cultivars dominated South Africa: HLH Mauritius and McLeans Red, causing a narrow harvest window competing with large volumes from Madagascar.
International market dynamics highlight the importance of extending the season to fill supply gaps occurring worldwide, particularly mid-March to end-April and early October to mid-November.
The breeding project faces challenges such as the long juvenile phase (5-10 years) of seedlings and low success rates but aims to overcome these with controlled environment growth, improved nutrition, high-density planting, and growth regulators to stimulate flowering.
Increased collection of germplasm and introduction of controlled pollination improve breeding efficiency.
New methods like irradiation and colchicine treatments are used to induce mutations and produce seedless or improved cultivars.
Cultivar evaluation, ongoing since 1992, is being consolidated to one location to reduce costs and increase efficiency, including grafting promising selections onto rootstocks to study performance and hasten maturity.
Cultivation practices like mulching, irrigation, nutrition, vegetative flush control, and pruning support better flowering and yield.
Budget constraints have shifted more financial responsibility to the industry, requiring more efficient research and evaluation methods.
New cultivars are continuously imported from sources like China, Israel, Australia, and Taiwan to broaden genetic diversity.
The program has started providing promising selections, but further evaluation and industry release will take place in coming years with continued emphasis on developing cultivars with varied ripening times, better fruit size, color, and quality.
The program aims to help growers maximize returns by supplying litchis during periods of low global supply and high demand.