Introduction of tea plant

The introduction of tea trees is simple and effective. Since the 1950s, the planting area of improved varieties has been expanded. For example, Yunnan big-leaf species have been introduced to Guangdong, Guangxi, Sichuan, Guizhou and other provinces, with an area of more than 1 million mu. Fujian, Zhejiang and other provinces have bred a number of excellent and high-yielding new varieties by using Yunnan big-leaf species introduced and domesticated as raw materials. New progress has been made in the introduction of tea from the south to the north. The northernmost boundary of tea distribution in China has moved from 34 °40 °N to 37 °49 °N, advancing more than 350 km northward. It has also introduced some tea varieties from the former Soviet Union, Japan, India, Vietnam and other countries, such as Georgia No. 1, No. 4, No. 6, No. 8, Tabei species, Assam species and Vietnamese big-leaf species.

There are two main points of introduction and domestication:

First, it is easy to succeed in introduction from areas with similar ecological conditions. Before introduction, it is necessary to understand the differences in latitude, altitude, climate, soil and other ecological conditions between the introduction area and the original area, in which the absolute minimum temperature and soil pH value in winter are the main factors. If the degree of difference is small, it can be introduced directly, and if the degree of difference is large, the "step-by-step migration method" will be adopted.

Second, the success or failure of introduction and domestication depends not only on the age of plant ontogeny, but also on the age of phylogeny. Using seed seedlings as introduction material, the age of ontogeny is young, the adaptability is strong, and the possibility of success is high; the phylogenetic age of hybrids is much younger than that of purebred varieties, so they have a strong ability to adapt to the new environment.

After the introduction of tea from the south to the north, the tea tree changed from tall to short, the leaves changed from large to small, from thin to thick, the layer of palisade tissue increased from one layer to two and three layers, the content of tea polyphenols decreased, the water extract increased, the flowering and fruiting decreased, and the germination period in spring was postponed, while the cold resistance was gradually enhanced. After the northern tea moved to the south, it generally germinated earlier, blossomed and fruited more, and the content of tea polyphenols increased. When introduction, according to the natural conditions and production of tea, clear introduction objectives; before a large number of introduction, we must first carry out a small number of trials to reduce unnecessary losses; but also do a good job in seedling quarantine to prevent the spread of diseases, pests and weeds.