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The purpose of the article is to provide and an exemplar of an inquiry-based unit on pollination for designing and implementing constructivist instructional practices while simultaneously providing outstanding teacher preparation. The unit on pollination was developed by preservice teachers through a partnership between the Monmouth Conservation Foundation and the Monmouth University School of Education. Through collective action, these institutions were able to enhance student learning on a vital part of the science curriculum, provide a rich clinical experience for pre-service teachers, and familiarize teachers with a more constructivist approach to pre-school science instruction.

We present a chromosome-level assembly of the Cascade hop (Humulus lupulus L. var. lupulus) genome. The hop genome is large (2.8 Gb) and complex, and early attempts at assembly were fragmented. Recent advances have made assembly of the hop genome more tractable, transforming the extent of investigation that can occur. The chromosome-level assembly of Cascade was developed by scaffolding the previously reported Cascade assembly generated with PacBio long-read sequencing and polishing with Illumina short-read DNA sequencing. We developed gene models and repeat annotations and used a controlled bi-parental mapping population to identify significant sex-associated markers. We assessed molecular evolution in gene sequences, gene family expansion and contraction, and time of divergence from Cannabis sativa and other closely related plant species using Bayesian inference. We identified the putative sex chromosome in the female genome based on significant sex-associated markers from the bi-parental mapping population. While the estimate of repeat content (~64%) is similar to the estimate for the hemp genome, syntenic blocks in hop contain a greater percentage of LTRs. Hop is enriched for disease resistance-associated genes in syntenic gene blocks and expanded gene families. The Cascade chromosome-level assembly will inform cultivation strategies and serve to deepen our understanding of the hop genomic landscape, benefiting hop researchers and the Cannabaceae genomics community.

The transcriptome from lupulin glands and associated bracts from cone tissue of hop (Humulus lupulus) c.v. ‘Cascade’, during three stages of development: early, mid, and late or near-harvest, was s...

Hops are valued for their secondary metabolites, including bitter acids, flavonoids, oils, and polyphenols, that impart flavor in beer. Previous studies have shown that hop yield and bitter acid content decline with increased temperatures and low-water stress. We looked at physiological traits and differential gene expression in leaf, stem, and root tissue from hop (Humulus lupulus) cv. USDA Cascade in plants exposed to high temperature stress, low-water stress, and a compound treatment of both high temperature and low-water stress for six weeks. The stress conditions imposed in these experiments caused substantial changes to the transcriptome, with significant reductions in the expression of numerous genes involved in secondary metabolite biosynthesis. Of the genes involved in bitter acid production, the critical gene valerophenone synthase (VPS) experienced significant reductions in expression levels across stress treatments, suggesting stress-induced lability in this gene and/or its regulatory elements may be at least partially responsible for previously reported declines in bitter acid content. We also identified a number of transcripts with homology to genes shown to affect abiotic stress tolerance in other plants that may be useful as markers for breeding improved abiotic stress tolerance in hop. Lastly, we provide the first transcriptome from hop root tissue.

SummaryWe present a chromosome-level assembly of the Cascade hop (Humulus lupulus L. var. lupulus) genome. The hop genome is large (2.8 Gb) and complex, and early attempts at assembly resulted in fragmented assemblies. Recent advances have made assembly of the hop genome more tractable, transforming the extent of investigation that can occur.The chromosome-level assembly of Cascade was developed by scaffolding the previously-reported Cascade assembly generated with PacBio long-read sequencing, and polishing with Illumina short-read DNA sequencing. We developed gene models and repeat annotations, and used a controlled bi-parental mapping population to identify significant sex-associated markers. We assess molecular evolution in gene sequences, gene family expansion and contraction, and time divergence using Bayesian inference.We identified the putative sex chromosome in the female genome based on significant sex-associated markers from the bi-parental mapping population. While the estimate of repeat content (~64%) is similar to the hemp genome, syntenic blocks in hop contain a greater percentage of LTRs. Hop is enriched for disease resistance-associated genes in syntenic gene blocks and expanded gene families.The Cascade chromosome-level assembly will inform cultivation strategies and serve to deepen our understanding of the hop genomic landscape, benefiting hop researchers and the Cannabaceae genomics community.

Hop is used primarily for bittering and flavoring of beer although new uses of hop have been implemented in poultry production, sugar processing and pharmaceuticals. Traditional hop breeding is a lengthy, expensive process. Modern selection methods such as marker-assisted selection are needed to greatly improve genetic gains per selection cycle as well as reduce the number of experimental lines evaluated in the field. Recent implementation of next generation sequencing enables the scanning of whole genomes for markers linked to traits of interest using an analysis called genome-wide association studies (GWAS). This study was initiated to identify markers associated with expression of 10 different traits in hop. Illumina Inc. technology sequencing of 116 genetically distinct hop cultivars from multiple regions of the world was performed. SNP marker identification was achieved using the TASSEL v3.0 UNEAK pipeline. Filtering of SNP markers resulted in a working group of 32,206 SNP markers screened across all 116 cultivars. Phenotypic data for all cultivars were collected over a 35-year period and data from four years were used. Mixed linear models analyses in TASSEL v5.0.0 were used for five of the traits while the remaining five traits were evaluated using general linear models. A total of 86 SNP markers were identified and reported as significantly associated with one of the 10 traits. Heritability for traits matched with those previously published. This is the first reported genome wide association study in hop and as such represents an important step forward in aiding marker assisted selection. Nevertheless, it remains that further validation of these SNP markers is needed prior to implementation in a breeding program.

Verification of clonal identity of hop (Humulus lupulusL.) cultivars within breeding programs and germplasm collections is vital to conserving genetic resources. Accurate and economic DNA-based tools are needed in dioecious hop to confirm identity and parentage, neither of which can be reliably determined from morphological observations. In this study, we developed two fingerprinting sets for hop: a 9-SSR fingerprinting set containing high-core repeats that can be run in a single PCR reaction and a kompetitive allele specific PCR (KASP) assay of 25 single nucleotide polymorphisms (SNPs). The SSR set contains a sex-linked primer pair, HI-AGA7, that was used to genotype 629 hop accessions from the US Department of Agriculture (USDA) National Clonal Germplasm Repository (NCGR), the USDA Forage Seed and Cereal Research (FSCR), and the University of Nebraska-Lincoln (UNL) collections. The SSR set identified unique genotypes except for 89 sets of synonymous samples. These synonyms included: cultivars with different designations, the same cultivars from different sources, heat-treated clones, and clonal variants. Population structure analysis clustered accessions into wild North American (WNA) and cultivated groups. Diversity was slightly higher in the cultivated samples due to larger sample size. Parentage and sib-ship analyses were used to identify true-to-type cultivars. The HI-AGA7 marker generated two male- and nine female-specific alleles among the cultivated and WNA samples. The SSR and KASP fingerprinting sets were compared in 190 samples consisting of cultivated and WNA accession for their ability to confirm identity and assess diversity and population structure. The SSR fingerprinting set distinguished cultivars, selections and WNA accessions while the KASP assays were unable to distinguish the WNA samples and had lower diversity estimates than the SSR set. Both fingerprinting sets are valuable tools for identity confirmation and parentage analysis in hop for different purposes. The 9-SSR assay is cost efficient when genotyping a small number of wild and cultivated hop samples (

Hop (Humulus lupulus L. var Lupulus) is a diploid, dioecious plant with a history of cultivation spanning more than one thousand years. Hop cones are valued for their use in brewing and contain compounds of therapeutic interest including xanthohumol. Efforts to determine how biochemical pathways responsible for desirable traits are regulated have been challenged by the large (2.8 Gb), repetitive, and heterozygous genome of hop. We present a draft haplotype‐phased assembly of the Cascade cultivar genome. Our draft assembly and annotation of the Cascade genome is the most extensive representation of the hop genome to date. PacBio long‐read sequences from hop were assembled with FALCON and partially phased with FALCON‐Unzip. Comparative analysis of haplotype sequences provides insight into selective pressures that have driven evolution in hop. We discovered genes with greater sequence divergence enriched for stress‐response, growth, and flowering functions in the draft phased assembly. With improved resolution of long terminal retrotransposons (LTRs) due to long‐read sequencing, we found that hop is over 70% repetitive. We identified a homolog of cannabidiolic acid synthase (CBDAS) that is expressed in multiple tissues. The approaches we developed to analyze the draft phased assembly serve to deepen our understanding of the genomic landscape of hop and may have broader applicability to the study of other large, complex genomes.

The earliest years’ experiences of children can ensure their future success, and parenting is noted to be an influential factor (Bronfenbrenner, 1979; Lamb et al., 2002). Many researchers theorized that parental involvement could encourage children to actively engage and improve their academic achievement in schools (Epstein, 2018). However, less attention was paid to the significance of parental involvement in infants’ development. This paper explores the role of parental involvement in infants’ development by reviewing and discussing abundant relevant studies. This study recommends that parental involvement should be considered as an affluent resource and a useful tool because it could provide rich information about infants’ individual needs and positively help infant teachers to improve their instructional skills.

The purpose of the study was to investigate differences in writers’ abilities to perceive global text organisation in self-, peer- and teacher/researcher-authored essays. Eight student participants...

This study explored the extent to which teachers integrate environmental education and local environmental knowledge into the curriculum of a secondary school in the Okavango Delta of Botswana. In doing so, the study explored the potential value of place-based education in redressing concerns brought to light in postcolonial critiques of education in southern Africa. The study found that teachers sought to integrate environmental education into the curriculum through lessons that included references to local place names and local flora and fauna, lessons addressing issues related to environmental resource management in the region, and the acknowledgment and celebration of traditional lifestyle activities in the schools. The study also found that efforts to integrate environmental education into the curriculum were limited by a lack of educational resources needed to support these endeavors as well as a lack of adequate teacher training promoting this educational goal. The results also illustrate t...

Genetic response in hop to fungal pathogen infection has been evaluated at the chromosomal level through QTL analyses but very little information exists on the expression of genes during infection periods. Raw GBS reads and phenotypic data from a previously published QTL analysis along with a newly assembled PacBio-derived hop reference genome were used to re-evaluate resistance to races v4/v6 of powdery mildew (PM; Podosphaera humuli). QTL analyses revealed two tightly linked regions of association on a single linkage group. The three SNP markers most tightly linked to PM resistance (found on contig 000559F) were observed downstream from a putative R-gene locus for powdery mildew resistance. This 230 kb region contained a series of seven putative R-genes surrounded by seven putative peroxidase-3 genes downstream and seven putative glucan endo-1,3-beta-glucosidase upstream and an expressed F-box domain protein. RNAseq data showed all putative R-genes along with all putative glucan endo-1,3-beta-glucosidase genes were expressed under diseased conditions, while none of the peroxidase genes were expressed. The second region contained three SNPs found on contig 002916F next to two putative R-genes. RNAseq data showed complex expression of exons contained in putative isoforms of R-genes. This preliminary information will prove valuable information for development of precise markers located either within or next to genes responsible for race v4/v6 PM resistance.

Hop (Humulus lupulus L. var Lupulus) is a diploid, dioecious plant with a history of cultivation spanning more than one thousand years. Hop cones are valued for their use in brewing, and around the world, hop has been used in traditional medicine to treat a variety of ailments. Efforts to determine how biochemical pathways responsible for desirable traits are regulated have been challenged by the large, repetitive, and heterozygous genome of hop. We present the first report of a haplotype-phased assembly of a large plant genome. Our assembly and annotation of the Cascade cultivar genome is the most extensive to date. PacBio long-read sequences from hop were assembled with FALCON and phased with FALCON-Unzip. Using the diploid assembly to assess haplotype variation, we discovered genes under positive selection enriched for stress-response, growth, and flowering functions. Comparative analysis of haplotypes provides insight into large-scale structural variation and the selective pressures that have driven hop evolution. Previous studies estimated repeat content at around 60%. With improved resolution of long terminal retrotransposons (LTRs) due to long-read sequencing, we found that hop is nearly 78% repetitive. Our quantification of repeat content provides context for the size of the hop genome, and supports the hypothesis of whole genome duplication (WGD), rather than expansion due to LTRs. With our more complete assembly, we have identified a homolog of cannabidiolic acid synthase (CBDAS) that is expressed in multiple tissues. The approaches we developed to analyze a phased, diploid assembly serve to deepen our understanding of the genomic landscape of hop and may have broader applicability to the study of other large, complex genomes.

The purpose of the study was to examine the differences among significant changes in the practice of individual teachers. Seventeen US teachers were interviewed about the most successful change in their teaching career. The differences in teacher change were based primarily on the source and impact of the change. The sources of change were divided into two categories: other-initiated or self-initiated. The level of impact was determined in three ways: by whether teachers described a new practice, a new direction, or a change in their beliefs. By organizing according to both the source and impact of the change, four types of change were identified: Response to School Initiatives, Professional Development Initiatives, Student-Centered Changes, and Self-Designed Changes. Self-Designed changes were further distinguished based on the time required for the change process. Implications for developing new strategies to foster teacher development are discussed.

The purpose of this chapter is to define gifted practitioners, to describe how they develop, and to show how their development can be fostered. Gifted practitioners are teachers who have continued to grow in their practice until they have become widely recognized as extraordinary teachers. The authors begin by examining the creative process, then showing how the creative process and teacher development are very similar processes. Both involve tacit learning through experience, the discovery of new ideas by making tacit knowledge explicit, and the further development of those ideas through design and evaluation. These ideas will be used as a basis for fostering giftedness in teaching. A case example will be used to provide an illustration of the gifted practitioner, followed by a discussion of the implications for the profession of teaching.

Hop is one of the few dioecious plants with dimorphic sex chromosomes. Because the entire Cannabaceae family is dioecious, hop and other members of this family are thought to have a relatively older sex chromosomal system than other plant species. Hop cones are only produced in female hops with or without fertilization. This has lead to most genomic research being directed toward female plants. The work we present provides genomic resources surrounding male plants. We have produced a draft genome for the male hop line USDA 21422M using a novel genome assembly method. In addition, we identified a 1.3 Mb set of scaffolds, which appear to be the male specific region based upon specificity with male hop accessions. This set includes a smaller high confidence total length 18 Kb set of scaffolds, which are supported by over 500 individuals, including the USDA world collection of hop varieties and two mapping populations, with genotyping by sequencing. We also have identified a portion of the Teamaker × 21422M linkage map to be associated with the pseudo-autosomal region (PAR). Within the genomic scaffolds, we identified a set of genes that are sex-linked and likely located in the PAR.