The cultural importance of indices: A comparative analysis based on the useful wild plants of Noorpur Thal Punjab, Pakistan

Introduction The use of cultural significance index (CSI), as a tool to calculate the use value of plants, is a growing trend in quantitative ethnobotany research. Researchers have developed several indices to estimate the significance of plants for humans. The evaluation of the cultural significance (CI) of plants in ethnobotanical studies is an essential quantitative method used in various types of investigations, including research on folk uses, naming and classification of plants. Methods Ethnobotanical data was collected from September 2014 to July 2016 through weekly and biweekly visits to the study area and interviewing people in the local communities. “Snowballing” and semi-structured interviews (socioeconomic issues and ethnobotany) methods were used for collecting ethnobotanical and ethnopharmacological data, regardless of age or gender. Results An index of cultural significance was applied to data of 129 wild plants from the Noorpur Thal. Logit regression showed that most of the medicinal plants were used as pot herbs in the study area, logit also showed that vegetable, fruit, fuel and ethnoveterinary results are statistically significant. From 129 wild plants 63 highly useful plants were selected for the CI studies. In addition to CI, we used other quantitative methods, such as the number of use reports (UR), use value index (UV), relative frequency of citation (RFC), relative importance index (RIs), and cultural value index (CV), for ethnobotanical and statistical analysis. The results showed a strong positive correlation between RFC/CI, CI/RIs (0.95) and a weak association between NU and RI at p < 0.05 (n = 261). The CI index indicated potential practical applications of each plant ranked according to the contribution of each separate application to survival in traditional cultures, together with estimates of intensity and exclusivity of the use for each. A CI-based dendrogram clearly depicted closely related species in the same place in the cluster. Conclusion The present study demonstrates that the area is rich in medicinal plant knowledge. The information reported by the traditional healers of this region is invaluable for further research in the field of cross-cultural ethnobotany and ethnopharmacology.