28 I EUROPEAN SEED I EUROPEAN-SEED.COM INTRODUCTION Tea plants are native to East Asia, and probably originated in the borderlands of north Burma and southwestern China. By annual per capita consumption of tea, the countries with the highest con- sumption are Northern Ireland (6.9 kg), Ireland (2.19kg) and United Kingdom (1.94kg). After China and India, Kenya is the largest tea producer in the world, with an annual production of 0.5 million tonnes. The crop was first introduced in Kenya in 1903, and first commercial- ization started in 1924. Since then the country has become a major producer of black tea and the crop is a major cash crop for Kenya. Kenyan tea has been the leading major foreign exchange earner for the country. Most tea produced in Kenya is black tea, with green tea, yellow tea, and white tea produced on order by major tea producers. There is a large diversity in tea varieties, the UPOV PLUTO data- base lists close to 1000 tea varieties. All the more reason to look into interesting crop. So European Seed sat down with Dr. Samson Kamunya, Chief Research Officer and Dr. Richard Chalo, geneticist at the Tea Research Institute in Kericho, Kenya to learn more about what it takes to develop new tea varieties. ES: TEA IS NOWADAYS A VEGETATIVELY PROPAGATED CROP. HOW DOES TEA BREEDING COMPARE TO THE BREEDING OF A SEED PROPAGATED CROP? SAMSON KAMUNYA (SK): The pioneer tea plantations were established using seedling tea plants comprising of mixed random collections from India and Sri Lanka. As these seedling populations comprised unique genotypes, uniform- ity in yields and tea quality could not be established, in addition to maintenance of good leaf picking table. This resulted in visual selection, on basis of general vigour, plucking point density and large shoot size, of elite bushes for vegetative propagation and commercialization. Thus, the only difference between seed- ling tea and vegetatively propagated tea fields is only in propagation. The mode of breeding is the same, only that current breeding efforts entail use of parents with known disparate attributes, and once seedling plants are fully established and evaluated for one pruning cycle consist- ing of four years, the best performing bushes are cloned by collecting cuttings from them and advanced to clonal field trials (CFT). The CFTs are evaluated for two pruning cycles (at least 8 years) with the best clones in terms of high yields and black/green tea quality are released to farmers for commercial utilization. Pictorial presentation of tea breeding scheme at the TRI is presented above. ES: WHAT ARE THE MOST IMPORTANT BREEDING GOALS IN YOUR TEA BREEDING PROGRAM? RICHARD CHALO (RC): The current glut of black tea in world market in the face of increased cost of production has resulted into dwindling revenue base from tea enterprise. As it has been projected that the market for black CTC tea will decline, while that for specialty tea will increase in the next 10 years, our primary focus is to develop tea varieties that are suitable for novel specialty tea products. Thus, availability of the requisite raw mate- rial for diversification of tea products is being given serious consideration for the Kenyan tea business to remain relevant. ES: TEA IS ATTACKED BY OVER ONE HUNDRED DISEASES, SUCH AS SEVERAL BLIGHTS, CANKERS, ROOT ROT AND MANY OTHERS. WHICH DISEASES ARE MOST IMPORTANT AND WHERE DO YOU FIND THE GENETIC DIVERSITY FOR THE RESISTANCES? SK: The most important disease is Armillaria root rot and Hypoxylon wood rot. The greatest diversity for genetic resistance is however found within seed- ling populations as each plant is a distinct genotype. In Kenya, these diseases are a major problem so long as growers pre- pare their lands properly during planting and practice good agricultural practices during the lifetime of the tea crop. EVER HEARD OF PURPLE TEA? A CLOSER LOOK AT TEA BREEDING IN KENYA. BY: MARCEL BRUINS Richard Chalo Samson Kamunya