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Premise of the study:Buchloë dactyloides (Poaceae) is an important component of Great Plains prairies and a popular drought-tolerant turfgrass alternative in North America. This species comprises an autopolyploid series, and microsatellite primers were developed to understand the distribution of genetic variation among cytotypes and across its large geographic range.Methods and Results:Fifteen microsatellite loci were designed and successfully amplified in six B. dactyloides populations. Within-population genetic diversity was comparatively high, consistent with B. dactyloides’ life history. Allelic variation at 13 loci was consistent with the cytotype established in chromosome-counted samples.Conclusions:This variable, interpretable set of loci allows for the determination of multilocus genotype in B. dactyloides individuals of varying cytotype. Data such as these from a range-wide sample set can provide important insights for germplasm conservation and crop improvement in this ecologically and economically important species.

Amphibian diseases, such as chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) and ranaviral disease caused by ranaviruses, are often linked to global amphibian population declines, yet the ecological dynamics of both pathogens are poorly understood. The goal of our study was to determine the baseline prevalence, pathogen loads, and co-infection rate of Bd and ranavirus across the Savannah River Site (SRS) in South Carolina, USA, a region with rich amphibian diversity and a history of amphibian-based research. We tested over 1000 individuals, encompassing 21 amphibian species from 11 wetlands for both Bd and ranavirus. The prevalence of Bd across individuals was 9.7%. Using wetland means, the mean (±SE) Bd prevalence was 7.9 ± 2.9%. Among toad species, Anaxyrus terrestris had 95 and 380% greater odds of being infected with Bd than Scaphiopus holbrookii and Gastrophryne carolinensis, respectively. Odds of Bd infection in adult A. terrestris and Lithobates sphenocephalus were 75 to 77% greater in metal-contaminated sites. The prevalence of ranavirus infections across all individuals was 37.4%. Mean wetland ranavirus prevalence was 29.8 ± 8.8% and was higher in post-metamorphic individuals than in aquatic larvae. Ambystoma tigrinum had 83 to 85% higher odds of ranavirus infection than A. opacum and A. talpoideum. We detected a 4.8% co-infection rate, with individuals positive for ranavirus having a 5% higher occurrence of Bd. In adult Anaxyrus terrestris, odds of Bd infection were 13% higher in ranavirus-positive animals and odds of co-infection were 23% higher in contaminated wetlands. Overall, we found the pathogen prevalence varied by wetland, species, and life stage.

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The hard, strong, very close-grained wood of common persimmon (Diospyros virginiana L.; Ebenaceae) is desirable for specialty products such as golf club heads, percussion sticks, billiard cues, and for wood turnery. The edible fruit of cultivated varieties is sold as pulp for use in puddings, cookies, cakes, and custards. Persimmon is usually propagated by grafting. Own-rooted clonal persimmon could offer several advantages to specialty fruit growers such as elimination of grafting, graft incompatibility issues, and improved rootstocks for variety testing. Four mature, grafted (male and female) persimmon genotypes and one hybrid were used for nodal explant culture. Nodal stem explants were cultured on Murashige and Skoog (MS) medium containing 10 μM zeatin, 3% (w/v) sucrose, and 0.7% (w/v) Bacto agar. Explants were routinely transferred to fresh medium every 3 weeks until shoot cultures were established. All nodal explants excised from grafted greenhouse plants produced at least one viable shoot. For in vitro rooting of microshoots, half-strength MS medium with 0, 5, 10, or 15 μM indole-3-butyric acid (IBA), 0.1 g·L−1 phloroglucinol, 3% (w/v) sucrose, and 0.7% (w/v) Bacto agar were tested with a 10-day dark culture treatment followed by culture in the light. Best rooting (14% to 87%) was achieved on medium containing 5 μM IBA for the common persimmon genotypes with means averaging from 0.5 to 3.9 roots per shoot. Ninety-one percent rooting with 5.3 ± 2.6 roots per shoot was achieved for the hybrid persimmon. Rooted plants were successfully acclimatized to the greenhouse.

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Ligumia nasuta (Say, 1817; Eastern Pondmussel) is an imperiled freshwater mussel (Unionidae) in eastern North America. Population declines in the Laurentian Great Lakes resulting from the introduction of dreissenid mussels and habitat destruction in the 20 th Century have greatly reduced and limited its distribution. To properly inform restoration and management efforts for L. nasuta, fine-scale genetic analyses must be performed on the remnant populations. This study used Illumina paired-end shotgun sequencing to identify potential microsatellite loci for L. nasuta, utilizing two samples to develop the Illumina paired-end shotgun library. Forty-eight primer pairs were tested on the remaining 24 samples. Twenty-nine of the 48 microsatellite primer sets screened were successfully amplified using 24 L. nasuta samples collected from the Great Lakes watershed. The estimated fragment size ranged from 167-445 base-pairs (bp) and the number of alleles per locus varied between 5 and 16 (mean = 9.7). Only five of the loci deviated significantly from Hardy-Weinberg expectations after Bonferroni corrections. Highlights  Microsatellite loci identified from two specimens using Illumina sequencing  48 primer pairs tested for amplification success on 24 L. nasuta specimens  29 loci were successfully screened and characterized