Seed biology imperative for conservation and restoration of Swertia thomsonii C.B. Clarke-an endemic medicinal plant of Himalaya.

Endemic medicinal plants deserve immediate research priorities as they typically show a limited distribution range, represent few and fragmented populations in the wild and are currently facing anthropogenic threats like overharvesting and habitat degradation. One of the important aspects of ensuring their successful conservation and sustainable utilization lies in comprehending the fundamental seed biology, particularly the dormancy status and seed germination requirements of these plants. Here, we studied the seed eco-physiology and regeneration potential of Swertia thomsonii-an endemic medicinal plant of western Himalaya. We investigated the effect of different pre-sowing treatments, sowing media and sowing depth on seed germination parameters of S. thomsonii. Seeds of S. thomsonii exhibit morphophysiological dormancy (MPD), i.e. when the embryo of the seed is morphologically and/or physiologically immature. Wet stratification at 4 °C for 20 days, pre-sowing treatment with 50 ppm GA3 and pre-sowing treatment with 50 ppm KNO3 were found ideal for overcoming dormancy and enhancing the seed germination of S. thomsonii. Furthermore, seed germination and seedling survival were significantly influenced by pre-sowing treatments, sowing media and sowing depth. The percentage of seed germination and seedling survival got enhanced up to 84-86% and 73-75% respectively when seeds were pre-treated with GA3 or KNO3 and then sown in cocopeat + perlite (1:1) at a depth of 1 cm. The information obtained in the present study outlines an efficient protocol for large-scale cultivation of S. thomsonii thereby limiting the pressure of overexploitation from its natural habitats and may also help in the restoration and conservation of this valuable plant species.

Integrating human footprint with ensemble modelling identifies priority habitats for conservation: a case study in the distributional range of Arnebia euchroma, a vulnerable species.

Climate change-driven rapid alteration of ecosystems globally is further complicated by growing anthropogenic pressures, especially in the ecologically sensitive mountainous regions. However, these two major drivers of change have largely been considered separately in species distribution models, thus compromising their reliability. Here, we integrated ensemble modelling with the human pressure index for predicting distribution and mapping priority regions across a whole range of occurrences for vulnerable species, Arnebia euchroma. Our results identified 3.08% of the study area as 'highly suitable', 2.45% as 'moderately suitable', and 94.45% as 'not suitable' or 'least suitable'. Compared to current climatic conditions, future RCP scenarios of 2050 and 2070 showed a significant loss in habitat suitability and a slight shift in the distribution pattern of the target species. By excluding the high-pressure areas of the human footprint from the predicted suitable habitats, we were able to identify the unique areas (70% of the predicted suitable area) that need special attention for conservation and restoration. Such models, if well implemented, may play a pivotal role in achieving the effective targets under the aegis of the current UN decade on ecological restoration (2021-2030) in accordance with SDG 15.4.