The agricultural civilization that originated in the Yangtze River Basin is an important part of Chinese civilization. Being one of the world-famous crop origin centers, the Yangtze River Basin is rich in biodiversity, and has bred many cultivated plants. This review has collected data of crops that originated in the Yangtze River Basin and information of plant remains found in Neolithic archaeological sites. By summarizing the environmental features and tracking the changes of vegetation since the Holocene in the Yangtze River Basin, we attempt to dissect the dynamics of plant use in this area and investigate the relationship between local cultivated plants and biodiversity. Our results indicate the agricultural civilization in the Yangtze River Basin greatly relied on rice production, and domesticated a large amount of fruit and aquatic vegetable crops, which reflects the adaptation and dependence to local subtropical evergreen broad-leaved forests and wetlands. When compared to other basins, the Yangtze River Basin is advantageous in allocation of ecological factors, and the characteristic of domesticated crops shows a typical feature of subtropical humid forest vegetation areas. Studying the natural and human factors related to crop domestication can help us to better understand the origin of agriculture civilization in the Yangtze River Basin. This work not only provides a reference for the conservation and utilization of plant genetic resources, but also plays a guiding role in promoting the construction of ecological civilization and sustainable development in the Yangtze River Basin.

Rice (Oryza sativa) is one of the most important crops in the world and serves as a staple food source for more than half of the world’s population. Research into when, where, and how rice was initially cultivated and eventually domesticated is essential. Research on these questions has been greatly advanced recently, along with nearly continuous research in both genetics and archaeology using newly developed analytical techniques. Here, we review the scientific understanding of rice domestication in the Yangtze River valley from both an archaeological and genetic perspective, and discuss the relationship between rice domestication and the Yangtze River civilization. Recent genetic research suggests that domesticated rice (O. sativa ssp. japonica) first occurred in southern China, including the Yangtze River valley and the Pearl River Basin. Current findings from archaeology support the view that O. sativa ssp. japonica was firstly domesticated in the Yangtze River valley ca.10,000-8,000 BP, and rice cultivation and agricultural development triggered the Yangtze River civilization. These findings enhance our understanding of rice domestication and related cultivation culture and also have implications for conservation of plant resources in the Yangtze River valley.

Tea is the most popular non-alcoholic beverage in the world. The domestication origin of cultivated tea plants has always been a focus of ecological research. This article summarizes the recent research progress, discusses remaining questions and makes suggestions for future research directions. Many wild relatives of cultivated tea plants are distributed in the Yangtze River Basin and its southern reaches, particularly in Yunnan, Guizhou, and Guangxi provinces. The pronunciation of “cha” is similar in the languages of southern ethnic groups, implying a single domestication origin of cultivated tea plants, most likely from ancient Bashu or Yunnan. However, studies on genetic structure reveal that multiple centers occur in the domestication origin of cultivated tea plants. For example, cultivated Camellia sinensis (L.) O. Kuntze, including some varieties, may have multiple domestication events. According to research from historical text, the cultivation center of tea plants migrated from west to east and then to south, which is supported by changes in genetic diversity. However, the first cultivated tea plant might have arisen in the most eastern region of the Yangtze River Basin based on a recent archaeological finding. We speculate that during the spread of tea knowledge, cultivated varieties introgression occurred from wild relatives to cultivars, or new cultivated tea plants were directly domesticated from local wild tea plants, leading to the genetic complexity and the language consistency of cultivated tea plants. More evidence is needed to confirm the ancestral types, origin sites and time, and domestication processes of cultivated tea plants, and the integration anaylysis of multiple disciplines such as tea culture, population genetics, phylogeography, anthropology, climate change, and archaeology should be more encouraged.

The Yangtze River Basin is key distribution area involved in the origin and evolution of kiwifruit as it possesses more important resources of wild kiwifruit species and populations of Actinidia chinensis-A. deliciosa species complex in the world. The seeds of kiwifruit were brought from Yichang, Hubei to Shanghai along the Yangtze River and reached New Zealand more than 100 years ago. Through cultivation and domestication, the initial seedlings gradually developed as a new fruit crop industry. In recent decades, great progress has been made on kiwifruit studies in China including genomic sequencing for diploid Actinidia chinensis cv. Hongyang, resequencing for interspecific relationships among the Actinidia species, molecular phylogeny and infrageneric classification of the genus Actinidia, and population genetic structure of certain species. However, more results are still needed to understand the origin, domestication and speciation of the kiwifruit species. Resource assessment on the base of the latest research is still lacking. It is of great importance to strengthen the protection and sustainable utilization of wild kiwifruit resources. Here we review the domestication history of cultivated kiwifruit, advances of systematics and classification in Actinidia, analyze the potential value and the present situation of wild kiwifruit resources in the Yangtze River Basin, and summarize distribution characteristics and threats to the endangered species of Actinidia in the basin. Finally, corresponding protection strategies for the existing problems are suggested, including the establishment of long-term protection mechanisms, the enhancement of basic scientific research and systematic evaluation of genetic resources, and the improvement of conservation standards of the germplasm resources for the sustainable utilization of wild kiwifruit resources.

Camellia oleifera is the dominant woody oil crop in China. According to current records, the cultivation history of C. oleifera as an oil crop may be less than 1,000 years, and the Yangtze River Basin may be one of the earliest cultivation areas. Wild relatives of C. oleifera are valuable genetic resources for breeding. Camellia oleifera belongs to Sect. Oleifera of the genus Camellia in the family Theaceae. Wild relatives of C. oleifera may include species in Sect. Oleifera and Sect. Paracamellia. However, the division of Sect. Oleifera and Sect. Paracamellia is still under debate, and the phylogenetic relationships among species remain unresolved. Sect. Oleifera and Sect. Paracamellia have the highest frequency of polyploids in the genus Camellia, and the same species may have various ploidies, which may be promoted by artificial selection and interspecies hybridization. The Yangtze River Basin is the main production area of C. oleifera, and the main distribution area of wild C. oleifera, thus containing rich genetic resources of wild C. oleifera. This study analyzed the distribution of species in Sect. Oleifera and Sect. Paracamellia of the genus Camellia and compared the results with the potential distribution areas of wild C. oleifera. Results show that drainage divides between the Yangtze River Basin and Pearl River Basin (Nanling Mountain, Miaoling Mountain, and adjacent regions) have the highest diversity of species in Sect. Oleifera and Sect. Paracamellia. Meanwhile, these regions are also potential highly suitable growing regions for wild C. oleifera, where there may be potential interspecies hybrid zones between C. oleifera and its wild relative species. Species diversity decreases from the south to the north, likely representing the dispersal direction from south to north. The potential interspecies hybrid zones between C. oleifera and its wild relative species may contain rich genetic diversity and provide natural breeding stations for selective breeding. These regions should be priority areas for research and conservation in order to explore and utilize genetic resources with important economic values.

Buckwheat is a pseudo-cereal with high nutritional and officinal value, a food crop outside of Poaceae. Cultivated buckwheat includes two species: sweet or common buckwheat (Fagopyrum esculentum), a self-incompatible, distylous annual and bitter or tartary buckwheat (F. tartaricum), a self-compatible, homostylous annual herb; the former depends on insect pollination for seed production. Thirty species have been named in the genus Fagopyrum (Polygonaceae) in the world. Investigations of morphology and genetic diversity suggest that Southwest China is the diversity center of Fagopyrum, especially in the area of Three Parallel Rivers, the upper Yangtze River Valley, where ancestral species of the two buckwheat crops were originated. Previous studies of basic biology on the buckwheat crops are briefly summarized here. Future studies of the taxonomical revision on the genus Fagopyrum, collections of wild germplasm resources, exploration of the interspecific relationships and the breeding of cultivars with superior agronomic traits are strongly needed. Palynological and archaeological evidences imply that the buckwheat crop has been cultivated at least 4,500 years in the Yangtze River Valley, and might have ever been a main food for local populations in the mountain areas, providing food resource for emerging of Yangtze River civilization. Deep understanding of the basic biology of buckwheat with modern techniques of genomics could clarify the origin of cultivated buckwheat and factors limiting seed production. The buckwheat could be a superior crop in the mountain areas if the traits with high agronomic and medicinal value can be excavated and exploited.

The Yangtze River Basin in China has abundant forest resources, including high species diversity, endemism, and genetic diversity. According to archaeological evidence, forest resources played a substantial role during the formation and development of Yangtze River Civilization in the Paleolithic and Neolithic Age. Food, energy, tools, architecture, and boats were all derived from forest resources. At present, the Yangtze River Basin and Pearl River Basin have become the domestic center of wood supply in China. Faced with insufficient timber supply and shortages of large diameter timber, responsible management of the Yangtze River Basin forest resources is crucial to guarantee domestic timber security in the future. Understanding the status of remaining resources and creating an improved preservation system are needed to effectively conserve forest germplasm resources in the Yangtze River Basin. A comprehensive investigation of forest germplasm resources and diversity analyses of important tree species and a preservation system that is composed of in situ, ex situ and vitro preservation is urgently needed.

Cultivated plants are the most important material basis for human survival and development. Growing global human population and personal demands result in increasing consumption of plant resources. The low genetic diversity of cultivated plants is a key factor that restricts production and quality improvements. Wild relatives of cultivated plants have accumulated rich genetic variations and adaptive traits during the process of long-term adaptive evolution, thus can be used as genetic donors in germplasm innovation and improvement of cultivated plants. However, the persistence and evolution of wild relative populations are threatened by habitat destruction and anthropogenic climate change. This review summarizes the progress of in situ and ex situ conservation of wild relatives of cultivated plants and offers conservation suggestions for wild relatives of cultivated plants based on the current situation in China. Moreover, technologies for the utilization of wild relatives of cultivated plants are reviewed and new insights on the sustainable use of genetic resources of wild crop relatives are also discussed. Finally, the status of conservation and utilization of the main cultivated plants that originated from the Yangtze River Basin are investigated, with four plants of different uses used as representatives.