High Level Of Genetic Diversity Research Articles

Molecular Evidence of the West-to-East Dispersal of Puccinia striiformis f. sp. tritici in Central Shaanxi and the Migration of the Inoculum from Gansu

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is an airborne disease. In China, it frequently develops initially in central Shaanxi and southwestern Gansu, and from there, inoculum spreads to the eastern wheat production regions. Field investigations have suggested that Pst could spread from the west to the east within central Shaanxi and that Gansu could serve as the inoculum source for central Shaanxi, but there is no direct evidence for this hypothetical dispersal route. In the current study, 321 Pst isolates collected from central Shaanxi and Gansu in the 2019-2020 and 2020-2021 winter wheat cropping seasons were genotyped using 23 pairs of KASP-SNP markers. The dispersion among subpopulations was analyzed using several approaches, and overall, the populations were found to exhibit high levels of genetic diversity. There was little genetic divergence (0.05 >Fst 0) within central Shaanxi. However, significant gene flow (Nm > 4) driven by wind-oriented dispersal from west (Baoji) to east (Weinan) occurred. There was also gene flow among the 4 Gansu subpopulations of Tianshui, Longnan, Pingliang, and Qingyang. Migration of the pathogen occurred between central Shaanxi and Gansu. Migration from Gansu to central Shaanxi was major compared with that from central Shaanxi to Gansu that was minor. Genetic variation occurred among isolates, instead of among subpopulations and within isolates. Linkage disequilibrium revealed that there was strong genetic recombination in the subpopulations from Gansu and central Shaanxi. Therefore, the present study provides molecular evidence that Pst spread from west to east in central Shaanxi and showed that Gansu (especially Longnan and Tianshui) was one of the major origins of the pathogen inoculum of wheat stripe rust in central Shaanxi. The results revealed the west-to-east transmission route of wheat stripe rust in central Shaanxi, being used to guide integrated management of the disease.

김해 야생차 군락지들의 차나무에 대한 유전적 다양성 분석

This study examined the genetic diversity of 13 tea tree samples to establish a variety discrimination system for the three Gimhae wild tea colonies using ISSR markers and to provide basic data for genetic diversity analysis. Seven primers that showed polymorphic and reproducible results among 100 ISSR universal primers were selected and used to amplify the genomic DNA of the 13 tea trees from three Gimhae wild tea colonies. The results demonstrated that all seven primers generated 117 bands with a 100% polymorphic band ratio. The average observed number of alleles was 2.0. The average effective number of alleles was 1.5323, while the average Nei's gene diversity was 0.3271. The average Shannon's Information index was 0.5001. The genetic similarity among the 13 tea tree samples ranged from 0.4444 to 0.8718, while the genetic distance ranged from 0.1372 to 0.8109. The 13 tea trees in three Gimhae wild colonies displayed a high level of genetic diversity, and the Dongsangdong and Sangdong samples in the three Gimhae wild colonies had a genetic similarity greater than 0.8 with Chinese tea species, indicating a close relationship with Chinese tea. Overall, these findings provide a theoretical basis for preserving and cultivating Gimhae wild tea trees.

Genetic connectivity and population expansion inferred from multilocus analysis in Lutjanus alexandrei (Lutjanidae-Perciformes), an endemic snapper from Northeastern Brazilian coast.

Previous studies about the genetic diversity, connectivity and demographic history in Lutjanidae fishes have reported a common pattern of genetic homogeneity and expansion in populations from Western South Atlantic. In the present work, we inferred the population structure, the levels of genetic diversity and the demographic history of the Brazilian snapper Lutjanus alexandrei, a recently described and endemic species from Northeastern coast of Brazil. Five different fragments, including mitochondrial DNA (Control Region, Cyt b and ND4) and nuclear DNA (Myostatin and S7) regions were analyzed in 120 specimens of L. alexandrei from four localities in Northeastern Brazil, representing the first study of population genetics in this species. High levels of genetic diversity were observed following a panmictic pattern, probably related to the larval dispersal by the current tides along the Brazilian coast. In addition, both demographic history and neutrality tests indicated that L. alexandrei has undergone population expansion during Pleistocene. In this sense, the sea level variation from this period could have increased the available resources and suitable habitats for the Brazilian snapper.

Population structure and genetic differentiation analyses reveal high level of diversity and allelic richness in crop wild relatives of AA genome species of rice (Oryza sativa L.) in India.

Crop wild relatives (CWRs) are vital sources of variation for genetic improvement, but their populations are few in genebanks, eroded in natural habitats and inadequately characterized. With a view to explore genetic diversity in CWRs of AA genome rice (Oryza sativa L.) species in India, we analyzed 96 accessions of 10 Oryza species by using 17 quantitative traits and 45 microsatellite markers. The morpho-quantitative traits revealed a high extent of phenotypic variation in the germplasm. Diversity index (H') revealed a high level of within-species variability in O. nivara (H' = 1.09) and O. rufipogon (H' = 1.12). Principal component (PC) analysis explained 79.22% variance with five PCs. Among the traits related to phenology, morphology, and yield, days to heading showed strong positive association with days to 50% flowering (r = 0.99). However, filled grains per panicle revealed positive association with spikelet fertility (0.71) but negative with awn length (- 0.58) and panicle bearing tillers (- 0.39). Cluster analysis grouped all the accessions into three major clusters. Microsatellite analysis revealed 676 alleles with 15.02 alleles per locus. High polymorphism information content (PIC = 0.83) and Shannon's information index (I = 2.31) indicated a high level of genetic variation in the CWRs. Structure analysis revealed four subpopulations; first and second subpopulations comprised only of O. nivara accessions, while the third subpopulation included both O. nivara and O. rufipogon accessions. Population statistics revealed a moderate level of genetic differentiation (FST = 0.14), high gene diversity (HE = 0.87), and high gene flow (Nm = 1.53) among the subpopulations. We found a high level of molecular variance among the genotypes (70%) and low among populations (11%) and within genotypes (19%). The high level of molecular and morphological variability detected in the germplasm of CWRs could be utilized for the improvement of cultivated rice.

Genetic inference of orchid colonization of a Costa Rican lava flow

AbstractThe dispersal and colonization of plant populations allow species to occupy novel habitats, migrate, and undergo range shifts in response to changing environmental factors and, as such, are fundamental ecological processes for ensuring the long‐term persistence of species. Natural landscape disturbance often generates habitats available for colonization. Patterns of colonization and population expansion can be inferred from the levels and partitioning of genetic variation of plant populations with known disturbance histories, such as recent volcanic eruptions. We sampled and mapped 496 individuals from two populations of the colonizing terrestrial orchid, Sobralia chrysostoma, on the 1992 lava flow of Volcán Arenal in central Costa Rica. We used neutral co‐dominant markers to genotype individuals and estimate population genetic statistics. Both populations had high mean levels of genetic diversity (P = 100%; AP = 3.31; He = 0.259) suggesting that the lava flow was colonized by numerous individuals that likely originated from multiple source populations. However, significant spatial genetic structure (SGS) was only present in one population at the smallest distance class (≤2 m) and was low (r = 0.032). That these large and genetically diverse populations had such low SGS and an absence of SGS, respectively is contrary to expectations and differs significantly from the pattern in Epidendrum radicans (Orchidaceae), with which S. chrysostoma is growing sympatrically. Our results suggest that these two populations either consist primarily of immigrant individuals or that seeds produced in situ dispersed over longer distances, thereby producing larger seed shadows and greater overlap of seed shadows.

Zoonotic simian malaria parasites in free-ranging Macaca fascicularis macaques and human malaria patients in Thailand, with a note on genetic characterization of recent isolates

Despite the natural occurrences of human infections by Plasmodium knowlesi, P. cynomolgi, P. inui, and P. fieldi in Thailand, investigating the prevalence and genetic diversity of the zoonotic simian malaria parasites in macaque populations has been limited to certain areas. To address this gap, a total of 560 long-tailed macaques (Macaca fascicularis) and 20 southern pig-tailed macaques (M. nemestrina) were captured from 15 locations across 10 provinces throughout Thailand between 2018 and 2021 for investigation of malaria, as were 15 human samples residing in two simian-malaria endemic provinces, namely Songkhla and Satun, who exhibited malaria-like symptoms. Using PCR techniques targeting the mitochondrial cytb and cox1 genes coupled with DNA sequencing, 40 long-tailed macaques inhabiting five locations had mono-infections with one of the three simian malaria species. Most of the positive cases of macaque were infected with P. inui (32/40), while infections with P. cynomolgi (6/40) and P. knowlesi (2/40) were less common and confined to specific macaque populations. Interestingly, all 15 human cases were mono-infected with P. knowlesi, with one of them residing in an area with two P. knowlesi-infected macaques. Nucleotide sequence analysis showed a high level of genetic diversity in P. inui, while P. cynomolgi and P. knowlesi displayed limited genetic diversity. Phylogenetic and haplotype network analyses revealed that P. inui in this study was closely related to simian and Anopheles isolates from Peninsular Malaysia, while P. cynomolgi clustered with simian and human isolates from Asian countries. P. knowlesi, which was found in both macaques and humans in this study, was closely related to isolates from macaques, humans, and An. hackeri in Peninsular Malaysia, suggesting a sylvatic transmission cycle extending across these endemic regions. This study highlights the current hotspots for zoonotic simian malaria and sheds light on the genetic characteristics of recent isolates in both macaques and human residents in Thailand.

Geography, climate and shifts in host plants distribution explain the genomic variation in the cactus moth

Landscape heterogeneity and the host plant use are factors suggested to play determinant roles in shaping the evolutionary history of herbivorous insects. However, the role of the reconfiguration of host plants distributions linked to Quaternary climate oscillations as drivers of contemporary population genetic structure is still poorly understood. Here, we formally examine the relative contribution of such factors on intraspecific diversification using the South American cactus moth, Cactoblastis cactorum, an herbivore insect specialized in the use of cacti as host plants. We assessed genomic variation using genome-wide SNPs and mitochondrial data in populations sampled across a broad geographical gradient where moths feed on different cactus species. We integrated demographic simulations and ecological niche modeling into a landscape genomics framework, to test alternative hypotheses of past and current population connectivity for both C. cactorum and its host plants. Regions exhibiting higher genomic diversity were evaluated for congruence with areas where suitable climatic conditions remained stable through time. Our results revealed that past spatial configuration of suitable habitat conditions and shifts of host plants distributions are the factors that better explain the intraspecific diversification. Genomic data also supported the hypothesis that areas of long-term habitat stability served as refugia for C. cactorum, enabling the maintenance of high levels of genetic diversity over time. Overall, our study highlights the importance of integrating inter-specific interactions and their spatio-temporal dynamics to better understand the relative importance of abiotic and biotic factors driving the diversification processes in herbivorous insects with broad geographical and restricted host ranges.

I Like This New Me: Unravelling Population Structure of Mediterranean Electric Rays and Taxonomic Uncertainties within Torpediniformes.

The present study focused on the three species of electric rays known to occur in the Mediterranean Sea: Torpedo torpedo, Torpedo marmorata and Tetronarce nobiliana. Correct identification of specimens is needed to properly assess the impact of fisheries on populations and species. Unfortunately, torpedoes share high morphological similarities, boosting episodes of field misidentification. In this context, genetic data was used (1) to identify specimens caught during fishing operations, (2) to measure the diversity among and within these species, and (3) to shed light on the possible occurrence of additional hidden species in the investigated area. New and already published sequences of COI and NADH2 mitochondrial genes were analyzed, both at a small scale along the Sardinian coasts (Western Mediterranean) and at a large scale in the whole Mediterranean Sea. High levels of genetic diversity were found in Sardinian populations, being significantly different from other areas of the Eastern Mediterranean Sea due to the biotic and abiotic factors here discussed. Sardinian torpedoes can hence be indicated as priority populations/areas to be protected within the Mediterranean Sea. Moreover, sequence data confirmed that only the three species occur in the investigated area. The application of several 'species-delimitation' methods found evidence of cryptic species in the three species outside the Mediterranean Sea, as well as in other genera/families, suggesting the urgent need for future studies and a comprehensive revision of the order Torpediniformes for its effective conservation.

Genetic and Haplotype Diversity of Manila Clam Ruditapes philippinarum in Different Regions of China Based on Three Molecular Markers.

China has the largest production yield of Manila clam Ruditapes philippinarum in the world. Most of the clam seeds for aquaculture are mainly derived from artificial breeding in southern China, likely resulting in the loss of genetic variation and inbreeding depression. To understand the genetic and haplotype diversity of R. philippinarum, 14 clam populations sampled from different regions of China were analyzed by three molecular markers, including COI, 16SrRNA and ITS. Based on the results of the COI and ITS genes, the 14 populations showed a moderate to high level of genetic diversity, with an average haplotype diversity of 0.9242 and nucleotide diversity of 0.05248. AMOVA showed that there was significant genetic differentiation among all populations (mean FST of the total population was 0.4534). Pairwise FST analysis showed that genetic differentiation reached significant levels between Laizhou and other populations. Two Laizhou populations showed great divergence from other populations, forming an independent branch in the phylogenetic tree. The shared haplotypes Hap_2 and Hap_4 of COI appeared most frequently in most clam populations. In contrast, 16SrRNA analysis of the clam populations revealed the dominated haplotype Hap_2, accounting for 70% of the total number of individuals. The haplotype diversity of the Laizhou population (Laizhou shell-wide (KK) and Laizhou dock (LZMT)) was relatively higher than other populations, showing multiple unique haplotypes (e.g., Hap_40, Hap_41 and Hap_42). These findings of genetic and haplotype diversity of clam populations provide guiding information for genetic resource conservation and genetic improvement of the commercially important R. philippinarum.

Genetic structure and gene flow in Myocastor coypus (Rodentia: Echimyidae) populations inhabiting a highly modified agroecosystem of the Pampas region

Abstract Assessing the genetic diversity and gene flow among populations in combination with ecological data provides valuable insight into the spatial use and genetic structure of wildlife. Anthropic impact generates landscape changes that threaten species by favouring their isolation in small patches and limiting their connectivity. However, in some cases, it can increase genetic exchange among wild populations. Here, we used a set of 16 microsatellites to study the genetic diversity, population genetic structure, and historical and current gene flow of coypu (Myocastor coypus) populations, a semi-aquatic rodent that inhabits watercourses of the highly anthropized agroecosystems of the Pampas region. Our results showed moderate to high levels of genetic diversity and revealed the existence of genetic structure among populations. Bayesian analysis showed different patterns of genetic structure among and within sampling sites. Also, the patterns of historical gene flow differed from that seen today. These results, together with previous studies, suggest that anthropic pressure, habitat fragmentation and ephemeral landscapes in a highly modified ecosystem could alter the dispersal patterns of coypus in their native range, which would otherwise be different in an environment with low anthropic impact. The results provide new information that could be used in effective conservation programmes.

Distribution, inducibility, and characteristics of Latilactobacillus curvatus temperate phages.

Aim: Temperate phages are known to heavily impact the growth of their host, be it in a positive way, e.g., when beneficial genes are provided by the phage, or negatively when lysis occurs after prophage induction. This study provides an in-depth look into the distribution and variety of prophages in Latilactobacillus curvatus (L. curvatus). This species is found in a wide variety of ecological niches and is routinely used as a meat starter culture. Methods: Fourty five L. curvatus genomes were screened for prophages. The intact predicted prophages and their chromosomal integration loci were described. Six L. curvatus lysogens were analysed for phage-mediated lysis post induction via UV light and/or mitomycin C. Their lysates were analysed for phage particles via viral DNA sequencing and transmission electron microscopy. Results: Two hundred and six prophage sequences of any completeness were detected within L. curvatus genomes. The 50 as intact predicted prophages show high levels of genetic diversity on an intraspecies level with conserved regions mostly in the replication and head/tail gene clusters. Twelve chromosomal loci, mostly tRNA genes, were identified, where intact L. curvatus phages were integrated. The six analysed L. curvatus lysogens showed strain-dependent lysis in various degrees after induction, yet only four of their lysates appeared to contain fully assembled virions with the siphovirus morphotype. Conclusion: Our data demonstrate that L. curvatus is a (pro)phage-susceptible species, harbouring multiple intact prophages and remnant sequences thereof. This knowledge provides a basis to study phage-host interaction influencing microbial communities in food fermentations.

Genotyping and epidemiological distribution of diarrhea-causing isolates of Giardia duodenalis in southeastern part of West Bengal, India.

The prevalence and genetic diversity of the protozoan pathogen Giardia duodenalis have been extensively studied worldwide. There is currently a lack of data regarding the genetic variability of the organism in eastern India. Understanding the circulating genotypes and associated risk factors is crucial for effective planning and implementing control measures. Therefore, the objective of the study was to conduct an epidemiological study to determine the prevalence and identify the various genotypes present. This survey adds to our knowledge on the occurrence and distribution of Giardia genotypes in the studied region. The overall prevalence was found to be 6.8%. This parasitic infection was significantly associated with two age groups, i.e., >0-5 years and >5-12 years. Using a multilocus genotyping method, we genotyped 52 human Giardia isolates that were obtained from diarrheal patients. Two distinct assemblages were found in the population-30.8% belonged to assemblage A; 63.5% belonged to assemblage B, prevalent in the population; and 5.7% belonged to a combined assemblage A+B. Sub-assemblage AII was found in 17.3% of the cases, followed by sub-assemblage AI (13.5%). High levels of genetic diversity were found within the population of assemblage B undergoing balancing selection. Overall, the high prevalence of the parasite observed, particularly among children, raises a major concern and necessitates implementation of robust control measures. Furthermore, we report the presence of numerous unique genotypes, circulating in this limited geographical boundary, which can be useful dataset for future studies.

Analysis of global Napier grass (Cenchrus purpureus) collections reveals high genetic diversity among genotypes with some redundancy between collections

Genetic diversity amongst genotypes of several Napier grass collections was analyzed and compared with the diversity in a set of open pollinated progeny plants. A total of 114,881 SNP and 46,293 SilicoDArT genome-wide markers were generated on 574 Napier grass genotypes. Of these, 86% of the SNP and 66% of the SilicoDArT markers were mapped onto the fourteen chromosomes of the Napier grass genome. For genetic diversity analysis, a subset of highly polymorphic and informative SNP markers was filtered using genomic position information, a maximum of 10% missing values, a minimum minor allele frequency of 5%, and a maximum linkage-disequilibrium value of 0.5. Extensive genetic variation, with an average Nei’s genetic distance value of 0.23, was identified in the material. The genotypes clustered into three major and eleven sub-clusters with high levels of genetic variation contained both within (54%) and between (46%) clusters. However, we found that there was low to moderate genetic differentiation among the collections and that some overlap and redundancy occurred between collections. The progeny plants were genetically diverse and divergent from the germplasm collections, with an average FST value of 0.08. We also reported QTL regions associated with forage biomass yield based on field phenotype data measured on a subset of the Napier grass collections. The findings of this study offer useful information for Napier grass breeding strategies, enhancement of genetic diversity, and provide a guide for the management and conservation of the collections.

The Role of Reproduction and Genetic Variation in Polish White-Backed Cows in the Breed Restoration Process.

Local breeds are the main reservoir of biodiversity of farm animals. According to FAO, they account for 87% of all described breeds in the world. To ensure that they are adequately protected, they should be continually monitored for genetic variation. Another crucial factor is reproduction, which is the most important guarantee of population growth. In the present study, genetic variation in 372 Polish White-Backed cows was determined using DNA microsatellite sequences, taking into account their parentage. Reproductive parameters were analysed as well, based on data from 3658 lactations of 1128 Polish White-Backed cows. The results indicate that despite the small initial population and the implementation of a moderate selection of animals, the existing population of Polish White-Backed cattle has a high level of genetic variation, reflected in the degree of heterozygosity (0.761). Regarding reproductive traits, despite their late age at first calving, Polish White-Backed cows were shown to be distinguished by very good fertility parameters in comparison to other breeds raised in Poland. These findings not only confirm the value of protecting local cattle breeds around the world but may also be of importance in developing selection indices for highly productive breeds, in which reproductive functioning should be one of the most important factors considered.

Morphological characteristics and genetic diversity of floating and attached Ulva prolifera––A case study in the Yellow Sea, China

Green tides in the Yellow Sea have occurred periodically since 2007, impacting the ecological environment and green algal communities along the coasts of Jiangsu and Shandong provinces in China. To investigate the morphological characteristics and genetic diversity of Ulva prolifera, we conducted surveys and comparative analyses of both its floating and attached forms along the coastal areas of Jiangsu and Shandong. The results revealed that the external morphology of the floating U. prolifera was multibranched. The attached U. prolifera displayed significant morphological variation among individuals. Based on the analysis of the amplified characteristic bands of the chloroplast gene, it was shown that both floating and attached U. prolifera could hybridize with Ulva linza. The genetic diversity of U. prolifera was studied using mitochondrial and chloroplast genome fragments. All floating U. prolifera and three strains of attached U. prolifera belonged to the same haplotype. The genetic diversity of floating U. prolifera was low, and there were some genetic differences with attached U. prolifera. The attached U. prolifera displayed a higher level of genetic diversity with abundant sites of variation and haplotypes.

COMBINING ABILITY FOR YIELD, OIL CONTENT, AND PHYSIO-BIOCHEMICAL CHARACTERS OF CANOLA (BRASSICA NAPUS L.) UNDER SALT STRESS CONDITIONS

Creating a half-diallel cross succeeded among seven diverse canola genotypes. The obtained 21 F1 hybrids with their seven parents underwent three salinity stress levels exposure—3.91 dsm1 (Normal), 6.24 dsm-1 (S1), and 7.81 dsm-1 (S2) —during the 2020/2021 growing seasons. Salinity treatments significantly reduced days to 50% flowering, plant height, number of primary branches, pods/plant, 1000-seed weight, seed yield/plant, seed oil content, relative water content, calcium, potassium, and the ratio between K+ and Na+ compared with a normal condition. Proline content, osmotic pressure, and Na+ were considerably higher under salinity stress conditions. Highly significant differences showed among the parents and hybrids for all traits across the tested environments. General (GCA) and specific (SCA) combining ability effects were highly significant for all attributes. The parental genotypes Serw4 and Pactol resulted as good general combiners for increased seed oil content (SOC), seed yield/plant (SYPP), and some of its components in research environments. The hybrid combinations H2/S × Serw4 and Serw4 × Serw6 were good specific combiners for days to first flower (DTF), number of primary branches (NPB), number of pods per plant (NP), a thousand seed weight (TSW), seed yield per plant (SYPP), seed oil content (SOC), proline content (ProC), Ca++, and K+/Na+. The SDS-PAGE analysis of seed proteins indicated high levels of genetic variability and revealed some vital biochemical markers for salt tolerance.

Doğu Anadolu Habitatlarından Domuz ayrığı (Dactylis glomerata L.) Türlerinin Moleküler Çeşitliliğinin ve Dağılımının Analizinde Buğday SSR Markerlerinin Uygulanabilirliği

Türkiye is one of the world's nations with the greatest flora diversity in different plants. Moreover, it possesses a high level of plant genetic diversity. Orchardgrass (Dactylis glomerata L.) is one of the most important fodder species used during cool seasons since it is a hardy and perennial plant. The identification of Orchardgrass cultivars is essential for maximizing cultivar utilization, and safeguarding breeders' intellectual property. Dactylis glomerata L. is an allogamous, variable, monospecific genus with multiple subspecies distinguished by morphology, chromosomal count, and distribution. This genus has a single species, Dactylis glomerata L, which is comprised of multiple subspecies whose traits have not been exhaustively characterized. Using DNA assays that evaluated the transferability of nine SSR primers designed for wheat loci, the genetic diversity of 44 orchardgrass genotypes from eight naturally distributed locales in the Eastern Anatolia Area of Türkiye was calculated. On average, 6.78 alleles were discovered for each of the nine SSR primers, for a total of 61 alleles. A total of 54 polymorphic alleles were identified, with an average of 6.78 per primer. Polymorphism information content (PIC) values ranged from 0.320 (WMC96) to 0.626% (XBARC187). The average polymorphism rate of 88.89% suggests a high amount of genetic diversity among all studied genotypes. The average expected heterozygosity (He) ranged between 0.178 (Ağrı) to 0.882 (Erzurum). The genetic separation ranged from 0.01 to 0.66. In conclusion, our findings indicate that the Dactylis glomerata L genotypes gathered in Eastern Anatolia are a rich source of genetic variability, supplying a vast array of genetic material for orchardgrass breeding efforts.

Seed Germination and Seedling Growth Influenced by Genetic Features and Drought Tolerance in a Critically Endangered Maple.

Understanding the adaptation of plant species will help us develop effective breeding programs, guide the collection of germplasm, and improve the success of population restoration projects for threatened species. Genetic features correlate with species adaptation. Acer yangbiense is a critically endangered plant species with extremely small populations (PSESP). However, no information was available on its seed germination and seedling growth in populations with different genetic characteristics. In this study, we investigated seed germination and compared the performance of 566 seedlings in 10 maternal half-sib families cultivated in Kunming Botanical Garden. The results showed that A. yangbiense seeds required an average of 44 days to start germinating, with a 50% germination rate estimated to take about 47-76 days, indicating slow and irregular germination. There is a trade-off between the growth and survival in A. yangbiense seedlings, with fast growth coming at the cost of low survival. Groups that were able to recover from a recent bottleneck consistently had higher relative growth rates. High genetic diversity and low levels of inbreeding are likely to be responsible for their improved survival during drought conditions and rapid growth under optimal environmental conditions. Our results suggest that maternal genetic traits might be used as indicators for conservation and population restoration. These findings provide us with new information that could be applied to support ex situ conservation and reintroduction of threatened species.

Conservation genetics of the steno-endemic Chorthippus lacustris (Orthoptera: Acrididae)

Invertebrate populations are amongst the most widespread species, inhabiting a variety of habitats, however there is limited conservation effort due to the scarce knowledge on their population genetics. Here, we assess levels of genetic diversity and population structure of the Epirus dancing grasshopper (Chorthippus lacustris), a steno-endemic species, located in Northwest Greece, exhibiting a fragmented distribution. By utilizing two mitochondrial genes and amplified fragment length polymorphisms (AFLPs), we detected moderate to high levels of genetic diversity of the focal populations. Haplotype network analysis revealed the existence of private haplotypes with low genetic differentiation suggesting a sudden expansion of the species in the study area with subsequent isolations on suitable habitats. Despite the low genetic differentiation between the studied populations, our data further suggest a subtle subdivision of the populations and the existence of three genetic clusters. Implications for insect conservation: Our study is the first to provide insights into the population genetics of the steno-endemic grasshopper C. lacustris, highlighting the importance of preserving focal populations. The species inhabits areas subject to high changes in land use and fragmentation. We argue that the preservation and management of suitable habitats is essential for the viability of the grasshopper populations.

Microsatellite Markers Based Molecular Variability among Locally Collected Cajanus cajan (L.) Millsp. Genotypes

Pigeonpea [Cajanus cajan (L.) Millsp.] is an important deep-rooted pulse crop, predominantly cultivated in rainfed areas by small and marginal farmers in India and South Africa. The crop’s productivity is severely constrained due to abiotic and biotic stresses in its agro-ecosystem. Molecular variability assessment in pigeonpea can be the key for successful breeding to mitigate the crop from future biotic and abiotic stresses. Molecular markers based genetic diversity analysis was done to evaluate locally collected 32 genotypes of pigeonpea. Total 20 microsatellite markers were used in the present analysis. Pigeonpea genotypes had higher level of genetic diversity. Microsatellite markers were able to discriminate the studied genotypes into three clusters. Most of the genotypes were grouped together according to their collection sites. The findings of the present study open the window of opportunity, for future research and exploitation of these locally collected genotypes for pigeonpea crop improvement.