A Sampling Strategy to Develop a Primary Core Collection of Miscanthus spp. in China Based on Phenotypic Traits

Abstract

Core collections can act as a genetic germplasm resource for biologists and breeders. Thirty-seven phenotypic traits from 471 Miscanthus accessions in China were used to design 203 sampling schemes to screen the genetic variations in different sampling strategies. The sampling was analyzed using the unweighted pair group method with arithmetic mean (UPGMA) and the Euclidean distance (Euclid). Several parameters including the variance of phenotypic value (VPV), Shannon–Weaver diversity index (H), coefficient of variation (CV), variance of phenotypic frequency (VPF), ratio of phenotype retained (RPR), the mean difference percentage (MD%) and the variance difference percentage of traits (VD%), the range coincidence rate (CR%) and the variable rate of quantitative traits (VR%) were used to evaluate the level of representation of the primary core collections developed by the different sampling schemes. Based on the optimal sampling strategies of prior selecting accessions, a primary core collection was constructed that maintained > 99.5% of the VPV and a CR% of 100%. This study indicates that the optimal sampling scheme consisted of prior and deviation sampling methods (PD) combined with a logarithmic proportional sampling strategy (LG) of 37.4% of the actual sampling ratio. Sampling before clustering can improve several parameters including the H, CV, RPR, VPF, and CR%. Sampling strategies including the genetic diversity index (G), logarithmic proportional (LG) and the square root proportional strategy (SG) can improve the H, whilst the constant strategy (C) can improve the RPR and VPF when the sampling scale was >30%. Furthermore, the proportional strategy (P) can improve the VPV.

Social-Ecologically More Sustainable Agricultural Production

“…In terms of bioenergy crops for combustion, woody species such as aspen (Populus tremula L.), Siberian elm (Ulmus pumila), and willow (Salix spp.) are among the commonly used species [9,10], followed by perennial herbaceous crops such as miscanthus (e.g., Miscanthus × giganteus Greef et Deuter) [11][12][13] and Sida (Sida hermaphrodita L. var. Rusby) [14].…”

“…For optimal cultivation of bioenergy crops, it is advisable to ensure that genetic material is always adapted to the growing economic and environmental challenges [2]. In this context, Liu et al [11] applied a sampling strategy on a miscanthus primary core collection to evaluate its role in reducing the size of the initial collection whilst retaining genetic diversity in the collection. This approach was found to improve the range of the coincidence rate without affecting the mean difference percentage.…”