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... more 10.000 glossed keywords and links to more than 100 figures and schemes, about 100 tables etc. can be obtained in addition to this limited INTERNET version either on CD-ROM or in modified design as book by CRC Press, Taylor & Francis Group, Boca Raton, USA

label >>> plant label

labeling: incorporation of an easily detectable signal into a DNA molecule; radioactive labeling is increasingly replaced by nonradioactive methods biot; in seed science, attaching labels to seed lots with information on variety identity, purity, and seed quality seed

labellum: in Orchidaceae, the lowest of the three flower petals, which differs from the other two; in lipped flowers, the platform formed by the lowest petal or fused petals bot

labiate: a member of the botanical family Labiateae bot

lablab: syn Bonavist bean, Dolichos lablab syn Lablab purpureus syn Lablab purpureus ssp. purpureus (Leguminosae), 2n = 2x = 22 hort >>> Table 16 >>> pulse

Lac operon: a cluster of structural genes specifying the enzymes acetylase, permease, and beta-galactosidase gene

lacinate: deeply cut, into irregular, narrow segments or lobes bot

laggard: a chromosome, which is not included in the daughter nuclei after anaphase cyto >>> lagging

lagging (of chromosome): delayed movement from the equator to the poles at anaphase of a chromosome so that it becomes excluded from the daughter nuclei cyto

lagging strand: DNA strand growing in the 3' to 5' direction, synthesized discontinuously biot

lamda phage: lamda temperate bacteriophage, size: 48.5 kb; it infects Escherichia coli biot

lamina: a flat, sheetlike structure (e.g., the blade of a leaf) bot

laminarin: a beta-1,3-glucan reserve phys

lampbrush chromosome: a particular type of chromosome shape, usually found in diplotene stage of animals including flies; it is a type of puffed chromosome; the loops of DNA strands form a lampbrush-like shape; puffed chromosome regions may also occur in plants (e.g., in Phaseolus beans) cyto >>> polyteny >>> polytene chromosome >>> puff

land classification: soil that is grouped into special units, subclasses, and/or classes according to their capability for use and treatments that are required for sustained agriculture, horticulture, and forestry agrlandmark: a labeled stick of different length and manufacturing used for marking fields, experimental plots, paths, or margins, usually after seed bed preparation prep meth

landrace: a set of populations or clones of a crop species produced and maintained by farmers; in breeding, a mixture of a great number of different genotypes, which are well adapted to the environmental conditions of its habitat; it shows only average, but reliable yield; in countries of highly developed agriculture, landraces have been superseded by highly advanced varieties; however, for selection landraces are a suitable material in which a great diversity of useful genotypes may be found tax >>> Figure 5

land use inspection: an official inspection of a non-pedigreed crop to determine the degree of contamination in the crop which may pose a varietal purity problem in a pedigreed seed crop planned to be grown on the same land the following crop season seed

larva: the wormlike immature form of certain insects; some are called caterpillars, grubs, or maggots zoo phyt

LASER >>> light amplification by stimulated emission of radiation

late crop: a crop or plant showing late maturation within a given season agr hort

latency: the state of being latent; the interval between exposure to a toxin or disease-causing organism and development of a consequent phyt

latency period >>> latency

latent >>> latency

latent infection: a chronic infection in which a host-pathogen equilibrium is established without any visible symptoms of disease phyt

latent period: the period between infection and the sporulation of the pathogen on the host phyt >>> latency

latent virus: a virus that does not induce symptom development in its host phyt >>> latent infection

lateral: belonging to or borne on the sides bot

lateral meristem: a meristem giving rise to secondary plant tissues, such as the vascular and cork cambia bot biot

lateral nerve(s): for example, in wheat, the nerves, which run along the length of the broad and narrow wings of the glume; in barley, the two pairs of nerves (inner and outer) lying toward the margins of the lemma and on either side of the median nerve bot

lateral root: roots arising from the main root axis bot


lateral shoot: shoots originating from vegetative buds in the axils of leaves or from the nodes of stems, rhizomes, or stolons bot

late replicating: ( often) heterochromatic regions of chromosomes, which show a later replication than the euchromatic once biot cyto

late replication: in microbiology, the rolling circle of replication of phage lamda, producing concatemers suitable for packaging in lamda heads bio; in cytology, heterochromatic regions of chromosomes, which show a later replication of DNA than the euchromatic ones cyto >>> lamda phage >>> heterochromatin

laterite: a weathering product of rock, composed mainly of hydrated iron and aluminum oxides, hydroxides, and clay minerals but also containing some silica agr

late selection: it is applied in self-pollinating crops, i.e, in the variable progeny of a cross for 3-4 generations, using either the >>> bulk breeding method or >>> single seed descent, and producing a mixed population of relatively homozygous individuals; the selection is made among these homozygous individuals;it is efficient because it produces plants with a reduced hybrid vigour, which can be misleading during the screening process, and it also produces a greater expression of recessive alleles, which are exhibited only in the homozygous state; llate selected plants have a higher heritability than those of >>> early selected plants; the advantage of late selection must be equated with the longer breeding cycle required meth >>> early selection

late-sown: sowing date later than the optimal time for a given crop or variety agr

latest safe sowing date: the date till which seeds can be sown without severe yield lost during the following year, usually in cereal crops agr

late wood: a result of secondary plant growth; very young branches have hardly any fascicular cambium; interfascicular cambium develops very early during the year, even before the beginning of secondary growth; the activity of the cambium increases branch diameter and the vascular bundles become elongated in cross section; far more xylem than phloem elements are produced; annual rings become clearly visible because at the beginning of each vegetation period (in spring) vessels (conducting function) and fibers (supporting function) with a wide lumen are assembled first, the so-called early wood; in the following season, elements with steadily narrowing volumes are produced; in autumn, only a few vascular elements with narrow lumina (late wood) form bot hort fore

latex: a white, commonly sticky substance produced in specialized tissues within a plant bot

latifoliate: broad-leafed bot

Latin square: in general, a set of symbols arranged in a checkerboard in such a fashion that no symbol appears twice in any row or column; it is used or subdividing plots of land for agricultural and breeding experiments, so that treatments could be tested even though the field had soil conditions, which might vary in an unknown fashion in different areas; it requires that the field is subdivided by a grid into subplots and the differing treatments be performed at consecutive intervals to plants from different subplots stat >>> Figure 9 >>> Table 26

Latin rectangle: a field design that is similar to the Latin square, just differentiated by the number of replication, which is not equal to the number of variants; the number of replications may be a third, a quarter, or a fifth of the number of variants; thus the number of replications is reduced stat >>> Figure 9

lattice: either lattice is a partially ordered set in which any two elements have a greatest lower bound and a least upper bound, or lattice is a discrete subgroup of the additive group of a Euclidean space, i.e., the lattice is closed under addition and negation, and that there is a non-zero minimum distance between two points of the lattice stat >>> lattice design

lattice design: an incomplete block design in which the number of treatments must be an exact square; there several types of lattice designs, e.g. alpha lattice, partially blalanced square lattice; the lattice design is “simple” if r=2; square lattice designs are also called nets; they are partially balanced with respect to an association scheme of >>> Latin square type; first associates concur once in blocks, second associates never; for a “rectangular” lattice design, there are n(n - 1) treatments in rn blocks of sizen-1; the construction is similar to that for a square lattice design, except that n cells are removed from the square array; for a “cubic” lattice design, there are n3 treatments in 3n2 blocks of size n; the treatments form a cube of order n; the blocks are the 1-dimensional slices stat >>> alpha lattice design >>> lattice square

lattice square: an experimental design for n2 treatments in r blocks, each of which is a n x n square array; the construction uses a square lattice design in 2r replicates; pairs of replicates in the old design are combined so that their blocks form the rows and columns, respectively, of squares in the new design stat meth>>> lattice design

lawn: a stretch of open, grass-covered land (e.g., one closely mowed, as near a house, on an estate, or in a park) agr

laws of inheritance >>> MENDEL’s laws of inheritance

layering: covering stems, runners, or stolons with soil causing adventitious roots to form at the nodes, enabling propagation by rooted cuttings; this procedure is used commercially to propagate many plants hort; in vitro layering, the horizontal placement of cultured shoots or nodal segments on agar growth medium in order to produce axillary bud formation biot

leaching: the washing out of material from the soil, both in solution or suspension agr

leader: a terminal leader is the uppermost branch or vertical tip of the tree; it eventually becomes the tree stem or trunk fore hort

leader sequence: a nucleotide sequence of the mRNA on which the ribosomes bind; inother words, nontranslated sequence at 5' end of mRNA, or N-terminal sequence of a protein constituting a signal for transport through a membrane, which is later removed biot

leading strand: DNA strand synthesized in the 5' to 3' direction biot

leaf: a thin, usually green, expanded organ born at a node on the stem of a plant, typically comprising a petiole (stalk) and blade (lamina), and subtending a bud in the axil of the petiole; it is the main site of photosynthesis bot

leafage >>> foliage

leaf analysis: chemical analysis, usually of growing plants for their nutrient status and other characteristics; a diagnostic tool for taking corrective measures while the crop is still in the field agr phys meth

leaf area index (LAI): the total leaf surface area exposed to incoming light energy, expressed in relation to the ground surface area beneath the plant (e.g., LAI = 3, the leaf area exposed to light is three times of the ground surface area) phys

leaf axil: the angle between a petiole and the stem bot

leaf bud: a bud producing a stem and leaf, unlike a flower bud, which contains a blossom bot

leaf color chart: a tool to optimize the use of nitrogen in cereal (mainly rice) cropping; farmers generally use leaf color as a visual and subjective indicator of the crop's nitrogen status and need for nitrogen fertilizer; the chart provides a simple, easy-to-use and inexpensive tool for efficient nitrogen management; often, it contains six gradients of green color from yellowish green (1) to dark green (6) and can guide nitrogen top-dressing agr meth

leaf curling: a trait that is expressed in several plants caused either by abiotic stress, diseases or mutant genes, e.g., the soft red winter wheat varieties “Kaskaskia” or “Penjamo 62” (registered in USA) exhibit leaf rolling; this trait is pronounced under some heat or drought stress; the expression is most visible just prior to heading; the flag leaves curl up lengthwise; or some triticales that tightly roll the leaves to give the appearance of an onion leaf agr

leaf cutting: a cutting made from a single leaf; a method for propagation (e.g., of succulents); a leaf can be knocked off or cut off the plant; either it spontaneously roots on the ground or it is placed in certain media for rooting hort meth

leaf fall: leaf abscission

leaf posture: the characteristic position of the foliage leaves on the stem axis, which imprints the plant habit of the species; it may contribute to optimal utilization of light and thus photosynthesis; there were several approaches to breed for specific leaf posture in order to improve photosynthetic capacity of, for example, cereals bot

leaf primordium: a lateral outgrowth from the apical meristem that develops into a leaf bot biot

leaf propagation: method of reproducing some ornamental plants; it involves removing a leaf from a parent plant, along with 3-4 cm of the petiole; this is called a leaf cutting; this leaf cutting is placed stem-first (or heel-first) into potting soil, water or some other rooting medium; within 40 to 50 days, a plantlet will begin to emerge, complete with its own root system; this method produces a variety that is the same as the parent plant from which the leaf cutting came (>>> clone or cloning) hort meth

leaf rot synpetiole rot: a condition caused by the application of too much fertilizer; because normal watering is unable to leach them out, fertilizer salts begin to accumulate in the soil and around the rim of the pot; where leaves and stems come in contact with the pot, they begin to develop lesions; eventually, these leaves and stems will wilt and turn mushy, i.e., they rot hort phyt

leaf senescence: a type of programmed cell death, during which leaf cells undergo cocoordinated changes in cell structure, metabolism, and gene expression, resulting in a sharp decline in photosynthetic capacity; a cytokinin class of plant hormones plays a role in controlling leaf senescence because a decline in the cytokinin level occurs in senescing leaves; external application of cytokinin often delays senescence phys

leaf sheath: a tubular envelope, as the lower part of the leaf in grasses bot

leafstalk: the footstalk or supporting stalk of a leaf bot >>> petiole

leaf vein: vascular bundles in the leaves; in the petiole and the midvein of the leaf the veins are very large; farther out into the mesophyll the veins may consist of only one xylem or phloem element; in these regions, these very small veins are called veinlets bot

leaky mutation: mutation that is very prone to reversion gene

least squares method: a method of estimation based on the minimization of sums of squares stat

lectin: a generic term for proteins extracted from plants (e.g., legumes) that exhibit antibody activity in animals chem phys

leghaemoglobin: an iron-containing, red pigment produced in root nodules during the symbiotic association between rhizobia and leguminous plants phys phyt agr >>> legume(s)

legume(s): plants showing a simple or single pistil and characterized by a dry fruit pod that splits open by two longitudinal sutures and has a row of seeds on the inner side of the ventral suture (e.g., bean, pea, soybean, locust); there are many valuable food, forage, and cover species, such as peas, beans, soybeans, peanuts, clovers, alfalfas, sweet clovers, lespedezas, vetches, and kudzu; sometimes referred to as nitrogen-fixing plants; legumes are an important rotation crop because of their nitrogen-fixing property bot agr >>> crop plants

legumin >>> globulin

leguminous plant >>> legume(s)

lemma: flowering glume; the lower or outer of the two bracts of the floret bot

lenticular: shaped like a biconvex lens, lentil-shaped bot

lentiform >>> lenticular

leptodermous: thin-walled or thin-skinned bot

leptokurtic (distribution): a flat-topped, bell-shaped curve of frequency distribution of a given character in a population stat

leptonema >>> leptotene

leptotene: during the first meiotic division, the first stage, in which the chromosomes appear as long, widely uncoiled, and single strands; the DNA of each of the chromosomes has replicated; each chromosome consists of two identical members (chromatids) cyto

lesion: a visible area of diseased tissue on an infected plant phyt

lethal: a gene or genotype that is fatal for the individual gene

lethal doses (LD): the concentration of a poison that kills a certain amount of cells, individuals, etc., for example, LD50 = 50 % of the cells or individuals are killed meth

lethal gene: a gene whose expression results in the premature death of the organism carrying it; dominant alleles kill heterozygotes, whereas recessive alleles kill homozygotes only gene

lethal load: it is usual in many organisms that normal individuals are carrier of genes, which have little effect in heterozygotes, but are recessive and detrimental or harmful in homozygous form, e.g.,  conifers are often carriers of a genetic load which is released by inbreeding (in particular selfing), and actually reduces the amount of selfing (inbreeding) in vital seeds compared to the frequency of selfing pollen gene fore hort >>> lethal gene

lethal mutation: a gene mutation whose expression results in the premature death of the organism carrying it gene >>> lethal gene

leucine (Leu): an aliphatic, nonpolar, neutral amino acid that, unlike most amino acids, is sparingly soluble in water chem phys

leucoplast: a colorless plastid that is involved in the metabolism and storage of starches and oils bot

levulose >>> fructose

liber >>> bast

library: in biotechnology and molecular genetics, a collection of cells, usually bacteria or yeast, that have been transformed with recombinant vectors carrying DNA inserts from a single species (e.g., cDNA), expression, or genomic library biot

lid: the cap of a boxlike seed capsule bot

life cycle, life history: in fungi, the stage or series of stages between one spore form and the development of the same spore again; there are commonly two stages in the life cycle (the imperfect, which may have more than one kind of spore, and the perfect), but there may be no development of one or the other phyt

life span: the longest period over which the life of any organism or species may extend phys

ligand: an atom, ion, or molecule that acts as the electron donor partner in one or more coordination bonds or a molecule (e.g., antibody), which can bind to specific sites on cell membranes; or an organic molecule which can form a chelated complex with a metal cation; also called chelating agent, e.g., EDTA, DTPA, or EDDHA chem phys

ligase: an enzyme that catalyzes a reaction that joins two substrates using energy derived from the simultaneous hydrolysis of a nucleotide triphosphate; in general, a joining enzyme, which closes single-strand breaks in DNA phys gene

light amplification by stimulated emission of radiation (LASER): a device that produces a nearly parallel, nearly monochromatic, and coherent beam of light by exciting atoms and causing them to radiate their energy in phase; it can be used for the elimination or manipulation of cell particles via a special microscope device micr

light reaction: during photosynthesis, those reactions that require the presence of light phys

light soil: a soil that has a coarse texture and is easily cultivated agr

ligneous: woody bot

lignification: converting into wood; cause to become woody bot

lignin: a complex, cross-linked polymer, comprising phenyl propene units, that is found in many cell walls; its function is to cement together and anchor cellulose fibers and to stiffen the cell wall; it reduces infection, rot, and decay chem bot

ligula: a scalelike membrane that covers the surface of a leaf; in some Compositae, a strap-shaped corolla; sometimes, a fringe of epidermal tissue found at the boundary between the sheath and the blade of a maize leaf bot >>> Table 30

ligulate: straplike, tongue-shaped bot

ligulate flower >>> ligulate >>> ligula

ligule >>> ligula

likelihood: the state of being likely or probable; probability stat

lime: compounds of calcium used to correct the acidity in soils agr

liming >>> lime

limited backcrossing: instead of complete, at least six cycles of backcrossing, only two or three cycles are coupled with rigorous selection to gain the advantage of transgressive segregation meth

line: a group of individuals of a common ancestry and more narrowly defined than a strain of variety; in breeding, it refers to any group of genetically uniform individuals formed from the selfing of a common homozygous parent gene

lineage: a chart that traces the flow of genetic information from generation to generation meth gene

linear: long and narrow, with parallel margins bot

line breeding: a system of breeding in which a number of genotypes, which have been progeny tested in respect of some characters, are composited to form a variety; examples of line varieties are from normally self-fertilized crops, e.g.,  “Gaines” wheat, meth >>> line

line of breeding >>> line

line of descent >>> line

line of inbreeding >>> line

line variety >>> line breeding

lining out: transplanting seedlings or rooted cuttings in rows in a nursery bed hort fore meth

linkage (of genes): the association of genes that results from their being on the same chromosome; linkage is detected by the greater association in inheritance of two or more nonallelic genes than would be expected from independent assortment; the nearer such genes are to each other on a chromosome, the more closely linked they are, and the less often they are likely to be separated in future generations by crossing over; all genes in one chromosome form one linkage group gene >>> association mapping

linkage desequilibrium: the nonrandom association of alleles at different gene loci in a population (e.g., when two loci occur close together on the same chromosome and selection operates to keep the allele combinations together) gene >>> association mapping

linkage disequilibrium >>> linkage desequilibrium

linkage group: all genes in one chromosome form one linkage group gene >>> linkage

linkage map: an abstract map of chromosomal loci, based on experimentally determined recombinant frequencies, that shows the relative positions of the known genes or other (DNA) markers on the chromosomes of a particular species; the more frequently two given characters recombine, the further apart are the genes that determine them gene >>> linkage >>> association mapping

linkage value: recombination fraction expressing the proportion of nonparental or recombinant versus parental types in a progeny; in diploids, the recombination fraction can vary between zero to one half gene >>> linkage >>> association mapping

linked (genes): genes or alleles showing less than 50 % recombination, which is typical for unlinked (independent) genes; depending on the strength of linkage, the linked genes tend to be transmitted together gene >>> linkage >>> linkage value

Linola: a new form of linseed known by the generic crop name “solin,” which produces a high-quality edible polyunsaturated oil similar in composition to sunflower oil agr

lint (linters): the long fibers of cotton seed; the short fibers generally remain attached to the seed in ginning; sometimes called “fuzz“; they are used mainly for batting, mattress stuffing, and as a source of cellulose; presence or absence of lint and fuzz are controlled by the interaction of four gene loci on non-homologous chromosomes; these loci were designated as N1, N2, Li3 and Li4, where N1 N1 confers the presence of fuzzy, N2 N2 confers inhibition of fuzzy initiation and development, and duplicate gene pairs, Li3Li3 and Li4Li4, determine the presence of lint; homozygosity for li3li3 and li4li4 might also inhibit fuzz from development; in other words, they were recessive epistatic to fuzz genes (DU, X. M.  et al., 2001) agr

lipase: an enzyme that degrades fats to glycerol and fatty acids chem phys

lipid(e): a member of a heterogeneous group of small organic molecules that are sparingly soluble in water but soluble in organic solvents; included in this classification are fats, oils, waxes, terpenes, and steroids; the functions are equally diverse and include roles as energy-storage compounds, as hormones, as vitamins, and as structural components of cells, such as membranes chem phys >>> Table 48

lipid body >>> lipid(e)

liposome(s): membrane-bound vesicles experimentally constructed to transport biological molecules biot

liquid culture: the culturing of cells on or in a liquid medium on supports or in suspension; the culture can be stationary or agitated prep

liquid nitrogen: nitrogen gas that has been condensated to a liquid and has a boiling point of –195.79°C; it is used for storage of tissue, organs, cells, or suspensions and for several cytological and molecular preparations chem >>> cryopreservation

L-notch planting: a form of slit planting involving two slits at right angles with the seedling placed at the apex of the “L” meth fore hort

loam soil: a soil containing sand, silt, and clay agr

local >>> indigenous

local infection: an infection just affecting a limited number of a plants phyt

local population: a group of individuals of the same species growing near enough to each other to interbreed and exchange genes tax

locule: a cavity of the ovary bot

locus (loci pl): a specific place on a chromosome where a gene is located; in diploids, loci pair during meiosis and, unless there have been translocations, inversions, etc., the homologous chromosomes contain identical sets of loci in the same linear order; at each locus is one gene; if that gene can take several forms (alleles), only one of these will be present at a given locus gene

locus-specific: plant characters or genetic activity that is exclusively correlated with a particular chromosomal locus gene

lodging: a state of permanent displacement of a stem crop from its upright position; it can cause considerable reduction in yield by storm damage, rots, insects, or excess of nitrogen agr >>> Table 34

lodging resistance: plants that can resist lodging by optimal root system, stiffer straw, or other characteristics (e.g., in cereal breeding, the introduction of “semi-dwarf genes” contributed to shorter plants and thus higher lodging resistance even when nitrogen fertilization is increased) >>> lodging >>> near-isogenic lines >>> semidwarf >>> Rht gene

lodiculae: two small, translucent, scale-like structures situated at the base of the floret bot

lodicule >>> lodiculae

loess (soil): unconsolidated, wind-deposited sediment composed largely of silt-sized quartz particles (0.015-0.05 mm diameter) and showing little or no stratification agr

loment(um): a dry schizocarpic fruit in the form of a legume or siliqua with constrictions formed between the seeds as it matures, so that the final fruit is composed of one-seeded, indehiscent loment segments bot

long-day plant: a plant in which flowering is favored by long days (>14 h daylight) and corresponding short dark periods; there are two types: species in which there is an absolute requirement for these conditions and others in which flowering is merely hastened by them bot

longevity: the persistence of an individual for longer than most members of its species, or of a genus and/or species over a prolonged period of geological time bot phys evol

long-plot design: a specific type of field experiment using preferentially long plots; a plot, the area to which an individual treatment is applied, can be any size, including a single plant growing in a pot, a five-acre field, or more; however, there are some considerations, including the equipment to be used in planting, harvesting, and treatment application, that determine size and shape of plots (e.g., space for the experiment, number of treatments, or specificity of character to be tested); if there is equipment to plant, harvest, and apply treatments to four rows at a time, then the logical plot width would be some multiple of four rows; the lengths of plots are more flexible than their widths (e.g., if the harvest from each plot has to be weighed, the scales may influence the length of plots; if the scales are designed to weigh hundreds of pounds, the plots must be large enough to provide a harvest weight that can be accurately determined by the equipment; increasing the length of plots is an easy way to do that); in general, once the plots are large enough to be representative of a much larger area, further increasing plot size will not significantly improve the accuracy of the results; plots that are larger than necessary take more field space and may increase the amount of work required for an experiment, but they usually will not adversely affect the test results unless the plots get so large that the plots within a block are no longer uniform; plots that are too small may prevent the accurate assessment of treatment effects; if the space available for an experiment is limited, more replications are usually more beneficial than having larger plots as long as plot size allows accurate assessment of treatment effects meth agr

long-term gene pool: a population with wide genetic variability established for long-term breeding objectives; lower selection pressure is applied when it is improved through recurrent selection; it can also provide genetic variability to other gene pools meth

long-term storage: storage of seeds in a gene bank longer than ten years seed

lopping: a procedure by which all the branches of a tree are cut off, except the leading shoot, as opposed to pruning, in which only some of the branches are cut hort meth

lower palea >>> lemma

low-input variety: a crop variety with low claims at macro- and micronutrient fertilizers, pest control, and agronomic measures agr

luciferin: a pigment of bioluminescent organisms that emits light while being oxidized chem phys

lumen: the central cavity of a cell or other structure bot

luminescence: the emission of light without accompanying heat phy

lunate: shaped like a half-moon bot

Lux: a unit of light measurement (= 0.0929 foot candles) once widely employed but now largely supplanted by photosynthetically active radiation units, such as µmolm–2s–1 (µmolEm–2s-1) and Wm–2 phy >>> measures

luxuriance: hybrids that are larger, faster growing, or otherwise exceed the parental forms in some traits; it is usually brought by complementary gene action present in the parents and combined in the hybrid gene >>> heterosis

lyase: an enzyme that catalyzes nonhydrolytic reactions in which groups are either removed or added to a substrate, thereby creating or eliminating a double bond, especially between carbon atoms or between carbon and oxygen phys

lyse: to destroy or disorganize cells by enzymes, viruses, or other means meth

lysimeter: an apparatus for electronically measuring water balance meth

lysis: cell rupture and death; it is applied if a bacterial cell is killed upon the release of phage progeny phys

lysosome: a membrane-bound vesicle in a cell that contains numerous acid hydrolases capable of digesting a wide variety of extra- and intracellular materials phys bot

lysozyme: an enzyme that is destructive of bacteria and functions as an antiseptic, found in certain plants phys

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