**1. Introduction**

Tropical plants are those that grow in warm climates. They typically grow best in areas where the temperature ranges consistently between 75 and 85 degrees Fahrenheit (24 and 29 degrees Celsius). The term "tropical" is used for a variety of plants, from palms to orchids. Tropical plants often have thick leaves that are waxy or shiny to help reduce evaporation and protect them from too much light. These plants also have flowers with colorful petals or leaves that attract pollinators like butterflies [1].

Tropical plants are among the most colorful and beautiful of all plant species. They are very diverse, ranging from small herbaceous plants to tall trees. Many tropical plants have been introduced in areas outside their natural range because they can tolerate colder temperatures than other species of the same genus or family. Tropical plants grow in a wide range of habitats, from the equator to the tropics. Tropical plants thrive in warm weather and grow in rainforests and deserts, and even on mountainsides [2]. These plants have adapted to their environment over time by developing unique features that help them survive in hot climates without suffering from heat stress or lack of moisture. Some tropical plants have thick stems that provide support during strong winds, while others still use their roots as storage organs called tubers or rhizomes that store nutrients until they are needed by the plant itself or by animals or humans [3].

The tropics have been a source of many new food crops that have been introduced to other regions of the world: sorghum (which originated in Africa, Winchell, [4]), soybean (from China, Singh, [5]), mung bean (from China, Shahrajabian, [6]), peanut (from South America, Ozias-Akins, [7]), cassava (from Brazil, Bester, [8]), lima bean, and fava bean (from Peru, [9] Santos, 2008). Several plant families have their center of diversity in the tropics. These include Arecaceae (palms), Lamiaceae (mint family), Lauraceae (laurel family), and Rubiaceae (coffee family). The largest family by the number of species is the Orchidaceae, with about 25,000 species.

Because most living forms thrive here, the tropical zone is home to the majority of plant and animal species in the world. The domestication of food crops is one of the most important developments in human history that made it possible for people to settle down and live in communities rather than wandering around with their herds and flocks.

#### **2. Tropical plants and ecosystem**

The tropics are usually defined as the area between the Tropic of Cancer and Tropic of Capricorn bounded by lines of latitude running through the Arctic and Antarctic circles, which is 23.5 degrees north and south of the equator, respectively. This area spans among Central America and South America, Africa, India, and Southeast Asia. Some tropical plants can also be found in subtropical regions such as California. The region lies beneath the intertropical convergence zone (ITCZ), a belt where tropical cyclones often form during their lifetime before moving into more temperate latitudes where they die out. However, they can be found year-round in some areas as well as at higher altitudes inside the tropics—like in Indonesia or Ecuador [10].

Tropical climates generally do not experience marked changes in temperature throughout the year, with average temperatures ranging from 18 to 24°C (64 to 75°F). The average annual rainfall varies greatly from region to region within this climate zone, with some areas receiving more precipitation annually, while other areas may receive less than that. Humidity is high throughout these regions, and climatic conditions are relatively constant throughout the year. Within tropical regions, distinct wet and dry seasons are caused by changes in the direction of wind flow that result in periods of more intense (wet) or weaker (dry) rainfall. The length and onset dates for wet and dry seasons vary by the geographic location within tropical zones [11].

The climate in the tropics is characterized by high temperatures and a nearly constant rate of evaporation. The evaporation results in a higher concentration of

#### *Emerging Trends to Improve Tropical Plants: Biotechnological Interventions DOI: http://dx.doi.org/10.5772/intechopen.108532*

water vapor in the air, which produces high relative humidity. The high temperature reduces the capacity of the air to hold water vapor so that even though there is high humidity, the air remains very dry. High temperatures also cause a lot of water to evaporate from the ocean's surface, which make it rain more on land and make the air even more humid [12]. The tropics are characterized by wide diurnal temperature variations with large day–night differences (diurnal range) and small annual ranges. The diurnal range is due to a strong daily heating-and-cooling cycle as well as large daily fluctuations in solar radiation on land surfaces (high solar intensity). Also, there are no big changes in the way the atmosphere moves, like seasonal winds or changes in cloud cover, that would have a long-term effect on the surface temperature, like months [13].

Tropical plants have a significant impact on the ecosystem. The tropics contain more than half of the world's species, and the majority of plants and animals live in this region. Tropical rain forests are vital to the planet because they act as carbon sinks and produce oxygen, which helps to regulate the global climate [14]. Tropical rain forests are also home to endangered species such as the Sumatran tiger, Bornean orangutan, Sumatran rhinoceros, sun bears, and Asian elephants, which need preservation. These animals depend on tropical rain forests for food and shelter. Tropical rain forests are also a valuable economic resource because they provide many useful things that people use every day [15]. Tropical plants are essential to the survival and preservation of other living organisms. One of the most important traits of tropical plants is that they purify water through their roots. This filtering of water through soil acts as a safeguard against many different diseases, such as cholera, dysentery, and typhoid. The roots grow deep into the ground and hold onto small amounts of water that can sustain plant life. Tropical plants also prevent soil erosion by acting as a natural buffer against strong winds, storms, floods, and wildfires. Due to their deep root systems, this allows for proper drainage of water from floods and droughts alike. Tropical plants also provide food for animals and people by acting as a natural canopy for fruits and nuts, which are used for both food and trade [16].
