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The North African catfish (Clarias gariepinus) is a significant species in aquaculture, which is crucial for ensuring food and nutrition security. Their high adaptability to diverse environments has led to an increase in the number of farms that are available for their production. However, long-term closed breeding adversely affects their reproductive performance, leading to a decrease in production efficiency. This is possibly caused by inbreeding depression. To investigate the root cause of this issue, the genetic diversity of captive North African catfish populations was assessed in this study. Microsatellite genotyping and mitochondrial DNA D-loop sequencing were applied to 136 catfish specimens, collected from three populations captured for breeding in Thailand. Interestingly, extremely low inbreeding coefficients were obtained within each population, and distinct genetic diversity was observed among the three populations, indicating that their genetic origins are markedly different. This suggests that outbreeding depression by genetic admixture among currently captured populations of different origins may account for the low productivity of the North African catfish in Thailand. Genetic improvement of the North African catfish populations is required by introducing new populations whose origins are clearly known. This strategy should be systematically integrated into breeding programs to establish an ideal founder stock for selective breeding. [ABSTRACT FROM AUTHOR]

Species of lichen-forming fungi (LFF) display an array of geographical distribution patterns. Among the broadly distributed lichen-forming fungal species, the degree of reproductive isolation and genetic substructure among populations varies widely, in some cases masking unrecognized diversity or meaningful biogeographical patterns. Lecidea atrobrunnea (Raymond ex Lam. & DC.) Schaer. s. lat. (Lecideaceae) is a widespread species complex that has been studied for over two centuries since its initial description. The diversity of the L. atrobrunnea group is highest in western North America, where a dizzying array of morphologies and chemistry can occur at local scales. Here we investigate whether the assumed cosmopolitan distribution of L. atrobrunnea s. lat. is an artifact of taxonomic limitations and masks biogeographical patterns in this species complex. To address these questions, we compiled sequence data from the standard fungal barcoding marker (ITS) for over 100 specimens within this complex, in addition to genome-scale data from a subset of these representing over 1600 single-copy nuclear genes spanning over 3 Mb of the genome. Our study corroborates the perspective that the morphologically and chemically variable Lecidea atrobrunnea group reflects a complex of distinct species-level lineages, with 42–83 candidate species inferred from the ITS region and high levels of diversity inferred from a subset of specimens using genome-scale data. However, both phenotype- and molecular-based species boundaries remained unsettled, with the most common nominal taxa recovered as highly polyphyletic and with conflict among different molecular species delimitation approaches. Our study also highlights the potential for geographically restricted species, with fascinating biogeographical patterns, challenging, in part, the assumed cosmopolitan distribution of L. atrobrunnea s. lat. This study provides valuable direction for future research that will be crucial in understanding diversification and establishing a robust taxonomy for this well-known species complex. [ABSTRACT FROM AUTHOR]

Cassava breeding is a critical aspect of sustainable agriculture to address the challenges of food security and climate change. The present study aimed to assess the combining ability of six Thai cassava elite varieties for four key traits, including fresh root yield (FRY), fresh shoot yield (FSY), harvest index (HI) and starch content (SC) through an analysis of the diallel mating design over two years. Parental lines HB80 and R5 showed significant positive general combining ability (GCA) effects for high SC; R1 and HB80 for low FSY; and R1 for high FRY and HI. The genetic effects for FSY, SC and HI were primarily influenced by the GCA of the progenitors, while specific combining ability (SCA) was more important for the FRY than the other three traits. Cultivation conditions were also found to impact the evaluation of genetic effects, with a poor growing environment affecting the expression of the genotype. This study provides a useful basis for the selection of parental lines for cassava breeding programs and insights into the genetic control of yield and related traits in the Thai elite cassava germplasm. [ABSTRACT FROM AUTHOR]

Leucobryum scalare was described in 1904 but its taxonomic status has been disputed, being reduced to a variety of Leucobryum aduncum or synonymized with Leucobryum aduncum. The taxonomic confusion of this taxon has remained unresolved. Hence, we revisited the taxonomic status of the taxon using phylogenetic and morphometric approaches. A total of 27 samples from Leucobryum aduncum var. aduncum and Leucobryum aduncum var. scalare were used to generate data from four markers, including ITS1, ITS2, atpB-rbcL spacer, and trnL-trnF. The concatenated dataset was used to reconstruct a phylogenetic tree. Both qualitative and quantitative morphological characters were measured and analyzed with Principal Component Analysis (PCA) and PERMANOVA. The results showed that the two taxa are closely related but they are reciprocally monophyletic. Both qualitative and quantitative characters could also separate Leucobryum aduncum var. scalare from Leucobryum aduncum var. aduncum as shown with PCA and PERMANOVA. We propose the resurrection of the species rank for Leucobryum scalare as separate from Leucobryum aduncum. This work highlights the need for a more thorough revision of Leucobryum to clarify the actual level of diversity in this genus. [ABSTRACT FROM AUTHOR]