Regulatory Mechanisms in Biosystems (E-Journal - Dnipro National University)
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Identifying migration flexibility and the environmental factors that influence variation in recruitment success in partially migratory Hawaiian fishes
No full textBehavior flexibility during the larval stage influences differential mortality, recruitment, and population dynamics; recruitment is poorly understood, yet important for understanding population persistence. The purpose of this dissertation was to examine fishes for migration flexibility and to identify factors at different spatiotemporal scales that are influential to differential survival within and across populations. I found that four underexplored native freshwater fishes of Hawai‘i exhibited a larval migratory strategy, but many were flexible. One species (Sicyopterus stimpsoni) showed all individuals made a migration, and the others showed 25 – 40 % did not migrate. Next, I examined if migrant (S. stimpsoni) and flexible species (Awaous stamineus) showed lunar rhythmicity at hatching and settlement. Migrants of the flexible species showed more hatching around the full moon and settlement around the new moon, and residents showed the opposite pattern. The divergence in life-history timing appears to be a balance between ecological costs and benefits. Next, I examined the influence of variation in localized conditions on the ratio of migrant to resident contingents (A. stamineus) in adult populations. Residents were least represented when stream flow and nutrients were low; however, the abundance of a common invasive predator showed a negative relationship with resident abundance. Highly urbanized systems may impose such stressful conditions that resident recruitment is diminished, which underscores the importance of stream management to conserve vulnerable native species. Lastly, I examined the frequency of contingents (A. stamineus), larval duration, and growth rates across ENSO. The proportion of migrants was highest during La Niña, and resident proportions were highest during weak La Niña and strong El Niño; once El Niño became very strong, resident proportions decreased. Migrants had faster growth than residents across all growing stages. Migrant growth rates in the early larval stage were highest during El Niño, and pre-settlement growth was highest during La Niña. Resident growth was fastest during neutral conditions. The duration of the early fast-growing period was shortest during El Niño, and the larval duration was longer. These dissertation findings show the importance of evaluating multiple influential scales to understand life-history strategies of individuals, especially those that inhabit multiple ecotypes.Life SciencesCollege of Science and Engineerin
La Feria De Las Flores August 1988
No full textFour Contestants on the stage at the La Feria De Las Flores in August 198
Letter from President Bush
No full textLetter from President Bush written to Irene Cipriano Congraulations on her Retirement in July 2,199
Developing growth-associated molecular markers via high-throughput phenotyping in spinach
No full textHigh-throughput imaging and genomic information can be combined to optimize marker development. Genome-wide association studies identified loci associated with plant growth traits. We identified candidate genes associated with plant growth and development. Despite advances in sequencing for genotyping, the lack of rapid, accurate, and reproducible phenotyping platforms has hampered efforts to use genetic analysis to predict traits of interest. Therefore, the use of high-throughput systems to phenotype traits related to crop growth, yield, quality, and resistance to biotic and abiotic stresses has become a major asset for breeding. Here, we assessed the efficacy of unmanned aircraft system (UAS)-based high-throughput phenotyping to obtain data for molecular marker development for spinach (Spinacia oleracea L.) improvement. We used a UAS equipped with a red-green-blue sensor to capture raw images of 284 spinach accessions throughout the crop cycle. Processed images generated orthomosaic and digital surface models for estimating canopy cover, canopy volume, and excess greenness index models. In addition, we manually recorded the number of days to bolting. Genome-wide association studies against a single-nucleotide polymorphism (SNP) panel obtained by ddRADseq identified 99 SNPs significantly associated with growth parameters. Some of these SNPs are in transcription factor and stress-response genes with possible roles in plant growth and development. The results underscore the utility of combining aerial imaging and genomic data analysis to optimize marker development. This study lays the foundation for the use of UAS-based high-throughput phenotyping for the molecular breeding of spinach.High-throughput imaging and genomic information can be combined to optimize marker development. Genome-wide association studies identified loci associated with plant growth traits. We identified candidate genes associated with plant growth and development. Despite advances in sequencing for genotyping, the lack of rapid, accurate, and reproducible phenotyping platforms has hampered efforts to use genetic analysis to predict traits of interest. Therefore, the use of high-throughput systems to phenotype traits related to crop growth, yield, quality, and resistance to biotic and abiotic stresses has become a major asset for breeding. Here, we assessed the efficacy of unmanned aircraft system (UAS)-based high-throughput phenotyping to obtain data for molecular marker development for spinach (Spinacia oleracea L.) improvement. We used a UAS equipped with a red-green-blue sensor to capture raw images of 284 spinach accessions throughout the crop cycle. Processed images generated orthomosaic and digital surface models for estimating canopy cover, canopy volume, and excess greenness index models. In addition, we manually recorded the number of days to bolting. Genome-wide association studies against a single-nucleotide polymorphism (SNP) panel obtained by ddRADseq identified 99 SNPs significantly associated with growth parameters. Some of these SNPs are in transcription factor and stress-response genes with possible roles in plant growth and development. The results underscore the utility of combining aerial imaging and genomic data analysis to optimize marker development. This study lays the foundation for the use of UAS-based high-throughput phenotyping for the molecular breeding of spinach
The Spotted Cleaner Shrimp, Periclimenes yucatanicus (Ives, 1891), on an Unusual Scleractinian Host
No full textThe spotted cleaner shrimp, Periclimenes yucatanicus (Ives, 1891), forms symbioses with sea anemones that may serve as cleaning stations for reef fishes [1]. This Caribbean palaemonid shrimp has usually been reported in symbiotic association with several species of actiniarian hosts, such as Condylactis gigantea (Weinland, 1860) and Bartholomea annulata (Le Sueur, 1817), or even with some corallimorpharians and a scyphozoan jellyfish [2]. During a field survey at Alacranes coral reef (26 June 2016; 22°27.14’ N, 89°45.79’ W; 13 m depth) on the Campeche Bank, Yucatán Peninsula, México, two spotted shrimps were observed swimming and walking above the polyps of the head coral Montastraea cavernosa (Linnaeus, 1767). Because none of the usual hosts of P. yucatanicus were detected nearby, we hypothesize that the shrimps were using the scleractinian coral as a host. Some other shrimp species commonly associated with actiniarians were previously reported to be living on stony corals, such as Ancylomenes holthuisi (Bruce, 1969) on Heliofungia actiniformis (Quoy and Gaimard, 1833) in New Guinea [3], and Periclimenes rathbunae Schmitt, 1924 on Dendrogyra cylindrus Ehrenberg, 1834 in Curaçao [4]. The observation (see Figure 1) of Montastraea cavernosa hosting Periclimenes yucatanicus is the second report of a palaemonid shrimp in association with a scleractinian coral in the Atlantic Ocean. The ecological implications of this association are unknown but could be related to a low local availability of usual hosts
