Plant Diversity in the Indigenous Home Gardens in the Eastern Himalayan Region of Mizoram, Northeast India

Abstract

The eastern Himalayan region of Northeast India is well known for its traditional home gardens, which are considered to play important roles in the maintenance of livelihoods of indigenous communities and conservation of biological diversity. This study determines the plant diversity in home gardens and their importance in conservation of plant genetic resources (PGR) through utilization. We studied 90 home gardens in detail located in six villages. Different aspects of the home gardens and plant species were observed directly and through discussion with the farmers. A total of 333 plant species (133 trees, 92 shrubs, and 108 herbs) belonging to 128 plant families with an average of 78 species per home garden were recorded. The size of home gardens ranged between 0.10 and 0.60 ha and showed significant (P<0.001) positive correlation between the garden size and plant species diversity. The species diversity index for trees, shrubs, and herbs was 4.76, 4.39, and 4.58, respectively. The species similarity within each life form was high with 50% for trees, 38% for shrubs, and 49% for herbs. Plant species in the home gardens could be grouped into 11 major use categories with the majority of plants in the medicinal or multiple use category. These home gardens are reservoirs of PGR and play a vital role in sustaining the livelihood of local inhabitants. They are also functioning as domestication and conservation centers of many crop relatives.