Much has been written about theory and practice in the law, and the tension between practitioners and theorists. Judges do not cite theoretical articles often; they rarely "apply" theories to particular cases. These arguments are not revisited. Instead the Essay explores the working and interaction of theory and practice, practitioners and theorists. The Essay starts with a story about solving a legal issue using our intellectual tools - theory, practice, and their progenies: experience and "gut." Next the Essay elaborates on the nature of theory, practice, experience and "gut." The third part of the Essay discusses theories that are helpful to practitioners and those that are less helpful. The Essay concludes that practitioners theorize, and theorists practice. They use these intellectual tools differently because the goals and orientations of theorists and practitioners, and the constraints under which they act, differ. Theory, practice, experience and "gut" help us think, remember, decide and create. They complement each other like the two sides of the same coin: distinct but inseparable.

Of Theory and Practice

INTRODUCTION. Internal Organization of the Plant Body. Summary of Types of Cells and Tissues. General References. DEVELOPMENT OF THE SEED PLANT. The Embryo. From embryo to the Adult Plant. Apical Meristems and Their Derivatives. Differentiation, Specialization, and Morphogenesis. References. THE CELL. Cytoplasm. Nucleus. Plastids. Mitochondria. Microbodies. Vacuoles. Paramural Bodies. Ribosomes. Dictyosomes. Endoplasmic Reticulum. Lipid Globules. Microtubules. Ergastic Substances. References. CELL WALL. Macromolecular Components and Their Organization in the Wall. Cell Wall Layers. Intercellular Spaces. Pits, Primary Pit--Fields, and Plasmodesmata. Origin of Cell Wall During Cell Division. Growth of Cell Wall. References. PARENCHYMA AND COLLENCHYMA. Parenchyma. Collenchyma. References. SCLERENCHYMA. Sclereids. Fibers. Development of Sclereids and Fibers. References. EPIDERMIS. Composition. Developmental Aspects. Cell Wall. Stomata. Trichomes. References. XYLEM: GENERAL STRUCTURE AND CELL TYPES. Gross Structure of Secondary Xylem. Cell Types in the Secondary Xylem. Primary Xylem. Differentiation of Tracheary Elements. References. XYLEM: VARIATION IN WOOD STRUCTURE. Conifer Wood. Dicotyledon Wood. Some Factors in Development of Secondary Xylem. Identification of Wood. References. VASCULAR CAMBIUM. Organization of Cambium. Developmental Changes in the Initial Layer. Patterns and Causal Relations in Cambial Activity. References. PHLOEM. Cell Types. Primary Phloem. Secondary Phloem. References. PERIDERM. Structure of Periderm and Related Tissues. Development of Periderm. Outer Aspect of Bark in Relation to Structure. Lenticels. References. SECRETORY STRUCTURES. External Secretory Structures. Internal Secretory Structures. References. THE ROOT: PRIMARY STATE OF GROWTH. Types of Roots. Primary Structure. Development. References. THE ROOT: SECONDARY STATE OF GROWTH AND ADVENTITIOUS ROOTS. Common Types of Secondary Growth. Variations in Secondary Growths. Physiologic Aspects of Secondary Growth in Roots. Adventitious Roots. References. THE STEM: PRIMARY STATE OF GROWTH. External Morphology. Primary Structure. Development. References. THE STEM: SECONDARY GROWTH AND STRUCTURAL TYPES. Secondary Growth. Types of Stems. References. THE LEAF: BASIC STRUCTURE AND DEVELOPMENT. Morphology. Histology of Angiosperm Leaf. Development. Abscission. References. THE LEAF: VARIATIONS IN STRUCTURE. Leaf Structure and Environment. Dicotyledon Leaves. Monocotyledon Leaves. Gymnosperm Leaves. References. THE FLOWER: STRUCTURE AND DEVELOPMENT. Concept. Structure. Development. References. THE FLOWER: REPRODUCTIVE CYCLE. Microsporogenesis. Pollen. Male Gametophyte. Megasporogenesis. Female Gametophyte. Fertilization. References. THE FRUIT. Concept and Classification. The Fruit Wall. Fruit Types. Fruit Growths. Fruit Abscission. References. THE SEED. Concept and Morphology. Seed Development. Seed Coat. Nutrient Storage Tissues. References. EMBRYO AND SEEDLING. Mature Embryo. Development of Embryo. Classification of Embryos. Seedling. References. Glossary. Index.

Anatomy of Seed Plants

Phenology affects nearly all aspects of ecology and evolution. Virtually all biological phenomena—from individual physiology to interspecific relationships to global nutrient fluxes—have annual cycles and are influenced by the timing of abiotic events. Recent years have seen a surge of interest in this topic, as an increasing number of studies document phenological responses to climate change. Much recent research has addressed the genetic controls on phenology, modelling techniques and ecosystem-level and evolutionary consequences of phenological change. To date, however, these efforts have tended to proceed independently. Here, we bring together some of these disparate lines of inquiry to clarify vocabulary, facilitate comparisons among habitat types and promote the integration of ideas and methodologies across different disciplines and scales. We discuss the relationship between phenology and life history, the distinction between organismal- and population-level perspectives on phenology and the influence of phenology on evolutionary processes, communities and ecosystems. Future work should focus on linking ecological and physiological aspects of phenology, understanding the demographic effects of phenological change and explicitly accounting for seasonality and phenology in forecasts of ecological and evolutionary responses to climate change.

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Toward a synthetic understanding of the role of phenology in ecology and evolution

In mammals, cadmium is widely considered as a non-genotoxic carcinogen acting through a methylation-dependent epigenetic mechanism. Here, the effects of Cd treatment on the DNA methylation patten are examined together with its effect on chromatin reconfiguration in Posidonia oceanica. DNA methylation level and pattern were analysed in actively growing organs, under short- (6 h) and long- (2 d or 4 d) term and low (10 mM) and high (50 mM) doses of Cd, through a Methylation-Sensitive Amplification Polymorphism technique and an immunocytological approach, respectively. The expression of one member of the CHROMOMETHYLASE (CMT) family, a DNA methyltransferase, was also assessed by qRT-PCR. Nuclear chromatin ultrastructure was investigated by transmission electron microscopy. Cd treatment induced a DNA hypermethylation, as well as an up-regulation of CMT, indicating that de novo methylation did indeed occur. Moreover, a high dose of Cd led to a progressive heterochromatinization of interphase nuclei and apoptotic figures were also observed after long-term treatment. The data demonstrate that Cd perturbs the DNA methylation status through the involvement of a specific methyltransferase. Such changes are linked to nuclear chromatin reconfiguration likely to establish a new balance of expressed/repressed chromatin. Overall, the data show an epigenetic basis to the mechanism underlying Cd toxicity in plants.

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In Posidonia oceanica cadmium induces changes in DNA methylation and chromatin patterning

Gibberellins (GAs) function not only to promote the growth of plant organs, but also to induce phase transitions during development. Their involvement in flower initiation in long-day (LD) and biennial plants is well established and there is growing insight into the mechanisms by which floral induction is achieved. The extent to which GAs mediate the photoperiodic stimulus to flowering in LD plants is, with a few exceptions, less clear. Despite evidence for photoperiod-enhanced GA biosynthesis in leaves of many LD plants, through up-regulation of GA 20-oxidase gene expression, a function for GAs as transmitted signals from leaves to apices in response to LD has been demonstrated only in Lolium species. In Arabidopsis thaliana, as one of four quantitative floral pathways, GA signalling has a relatively minor influence on flowering time in LD, while in SD, in the absence of the photoperiod flowering pathway, the GA pathway assumes a major role and becomes obligatory. Gibberellins promote flowering in Arabidopsis through the activation of genes encoding the floral integrators SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), LEAFY (LFY), and FLOWERING LOCUS T (FT) in the inflorescence and floral meristems, and in leaves, respectively. Although GA signalling is not required for floral organ specification, it is essential for the normal growth and development of these organs. The sites of GA production and action within flowers, and the signalling pathways involved are beginning to be revealed.

Gibberellin as a factor in floral regulatory networks

Temperature records (1963–2009) from Alstonville, northern New South Wales, Australia, were examined for long-term trends using two methods: annual smoothing using a sine curve; and temperature-based phenological models applied to different parts of the year. Both methods indicated strong seasonality in warming, with winters increasing by 1.5°C over the period, but summers largely unchanged. Estimates of spring custard apple flower development time decreased by c. 13 days (20%) from 1963/64–2008/09; estimates of autumn litchi flush development decreased by c. 8 days (7%); estimates of winter macadamia flush development decreased by c. 17 days (12%) but summer flush development was not affected; and estimates of mango fruit development decreased by c. 12–16 days (7–8%) depending on variety.

https://www.tandfonline.com/doi/pdf/10.1080/01140671.2010.550627

Late 20th century warming in a coastal horticultural region and its effects on tree phenology

Macadamia (Macadamia integrifolia) is a recurrent flushing tree, with buds alternating between growth and quiescence. Here we report on factors governing bud release. We used staggered tip-pruning (equivalent to branch decapitation) to generate a range of trees with different flush maturities, but uniform maturity within any given canopy. We then tip-pruned the trees again to remove the most recent flush, and monitored the time taken for visible axillary bud emergence. New flushes appeared 9-16 days after tip-pruning. The slowest bud emergence was associated with flushes of intermediate maturity, approximately 7 weeks old. Overall, the variation in bud emergence was most closely related to the growth rate of the most recent flush at the time of pruning, and not related to the levels of stored carbohydrates.

On the control of bud release in macadamia (Macadamia integrifolia)

Yields of macadamia (Macadamia integrifolia, M. tetraphylla, and hybrids) orchards tend to increase with increasing tree size up to 94% light interception. Beyond this, there is some indication that crowding leads to yield decline, but the evidence is limited to one site. Increasing tree size and orchard crowding also present numerous management problems, including soil erosion, harvest delays, and increased pest and disease pressure. The aim of this study was to better characterize long-term yield trends in mature orchards and to assess the effects of manual and mechanical pruning strategies on yield, nut characteristics, tree size, and economics. We monitored yield at four sites in mature ‘344’ and ‘246’ orchards for up to seven years and confirmed a decline in yield with crowding for three of the sites. There was a small increase in yield over time at the fourth site, which may reflect the lower initial level of crowding and shorter monitoring period compared with the other sites, and highlights the need for long-term records to establish yield trends. Pruning to remove several large limbs from ‘246’ trees to improve light penetration into the canopy increased yield relative to control trees but the effect was short-lived and not cost-effective. Removal of a codominant leader from ‘344’ trees reduced yield by 21%. Annual side-hedging of ‘246’ trees reduced yield by 12% and mechanical topping of ‘344’ trees caused a substantial reduction in yield of up to 50%. Removal of limbs in the upper canopy to reduce the height of ‘344’ trees had less effect on yield than topping but re-pruning was not practical because of the extensive regrowth around the pruning cuts. Tree size control is necessary for efficient orchard management, but in this study, pruning strategies that controlled tree size also reduced yield. Research into the physiological response to pruning in macadamia is required to improve outcomes.

https://journals.ashs.org/downloadpdf/journals/horttech/23/1/article-p64.pdf

Production Trends in Mature Macadamia Orchards and the Effects of Selective Limb Removal, Side-hedging, and Topping on Yield, Nut Characteristics, Tree Size, and Economics

The effects of different levels of carbon limitation on the flower development of custard apple were studied in two defoliation experiments. The duration of flower development was unaffected by moderate carbon limitation, but increased with severe limitation. Both moderate and severe limitation caused a decrease in flower dry weight. Some of the data collected were combined with data from an earlier study to develop a model of the dependency of the duration of flower development on temperature. The model was applied to long-term weather records from Alstonville, northern New South Wales, to illustrate the effects of late 20th century warming on the duration of flower development.

Effects of defoliation on flower development in atemoya custard apple (Annona cherimola Mill. × A. squamosa L.) and implications for flower-development modelling

Trevor Olesen

Papers

Late 20th century warming in a coastal horticultural region and its effects on tree phenology

On the control of bud release in macadamia (Macadamia integrifolia)

Production Trends in Mature Macadamia Orchards and the Effects of Selective Limb Removal, Side-hedging, and Topping on Yield, Nut Characteristics, Tree Size, and Economics

Effects of defoliation on flower development in atemoya custard apple (Annona cherimola Mill. × A. squamosa L.) and implications for flower-development modelling

The Timing of Pruning Affects Flush Development and Flowering in 'Honey Gold' Mango