**6. Tropical plant species—as a source of fruits and lumber**

In addition to flowering and herbaceous plants, tropical plant species are at the forefront to fulfill the fruit and lumber demands of the rapidly increasing population. The most valuable tropical fruits are jackfruit, dragon fruit, lychee, banana, passion fruit, papaya, acai, rambutan, coconut, and mango. They are not only an important source of nutrients, bioactive compounds, and primary as well as secondary antioxidants but also bring high economic returns to the growers. So, tropical fruit plants are in high demand worldwide owing to their nutritional and nutraceutical value. Recent updates in cultivation techniques, efforts to develop climate-resilient genotypes, control of fruit diseases, exploitation of postharvest physiology, and the discovery of bioactive compounds have further promoted the adoption and usage of tropical fruits. As a result, numerous fruit species have been explored that have the potential to be transformed from minor tropical fruits to major tropical fruits and can be introduced elsewhere [13].

Tropical lumber trees are also very important for domestic as well as industrial applications resulting in the substantial economic growth of lumber-producing areas. Furthermore, such areas not only contribute to the conservation of animal and plant biodiversity but are of central importance in the global trade of sawn wood, roundwood, and plywood too. They are so important that only rosewood has a market of 26 billion USD in China per annum. More than 600 species of lumber trees have been explored so far, in different tropical regions, worldwide. Though numerous tree species are on the verge of extinction, researchers are striving hard to protect and promote them using various interventions. Advancements in clonal propagation, micrografting, nodal culture, genetic transformation, development of DNA databases for the forensic identification of lumber [14], and establishment of seed banks have helped not only to secure endangered plant species but have also helped to improve their production and quality.
