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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

“cabernet sauvignon”: the principal grape cultivar of Bordeaux, France, producing the red wine known as “claret” in England hort

cacao: the tree is often called cacao, while the product is called cocoa, from which chocolate is manufactured; the cacao plant is a evergreen flowering tree native to wet, warm forests of South and Central America; the centre of origin of cacao is on the eastern equatorial slopes of the Andes, and it occurs throughout the Amazon Valley where it provides an interesting example of a cline; all the wild trees in the centre of origin are self-incompatible; as one moves down the Amazon, self-compatible types become increasingly common and, at the river mouth, they are all self-compatible; all the cacao in West Africa is self-compatible and very uniform, with a very narrow genetic base; this tree grows to 40 feet (12 m) tall; after flowering, 10 to 14-inch long red fruit pods develop; in each pod are almond-shaped cacao beans and pulp; chocolate is made from the beans in the pods of the cacao plant, Theobroma cacao (Sterculiaceae), 2n = 2x = 20 hort

.......... much more on CD-ROM

caliper: an instrument to measure diameters of trees or logs fore >>> hypsometer

capture probe - Fangsonde f: phage or antibody probes that bind proteins in a sample such that their relative expression levels can be detected biot

cash crops: a readily salable crop that is grown and gathered for the market (as vegetables or cotton, tobacco, coffee, sisal etc) agr >>> truck crop

catch crop: a method of increasing agricultural or horticultural productivity by filling in the empty spaces, for example, it is created when slower-growing vegetables are harvested with fast-growing crops; in general, a short duration crop grown in between two main crops in a rotation to maximize cropping intensity, e.g., summer >>> greengram grown in between two main cereal crops (wheat-greengram-maize); usually grown without any extra nutrient application and expected to feed on the residues of nutrients applied to the main crops agr >>> stubble crop >>> under­plant crop

cavity: a tunnel left inside the maize stalk, e.g. from European corn borer feeding, or a hole or hollow area, especially inside a tree phyt

chimera - Chimäere f: a tissue containing two or more genetically distinct cell types, or an individual composed of such tissue; chimeral plants may originate by grafting, spontaneous mutation, induced mutation, sorting-out from variegated seedlings, mixed callus cultures, or protoplast fusion; one of the earliest described cases of a graft chimera was the “Bizzaria” orange, which arose after a scion of sour orange had been grafted onto a seedling of citron late in the 17th century; the vast majority of variegated-leaf chimeras have arisen by spontaneous nuclear or plastid mutation; colchicine has been widely used to induce cytochimeras of fruiting plants; structural classification of chimeras includes periclinal, mericlinal and sectorial chimeras; periclinal describes the stable, “hand-in-glove” arrangement of the tunica-corpus region; mericlinal, describes a type of periclinal where only part of a layer is mutant; and sectorial, describes a form where a solid sector through all apical layers is mutant; the conventional method of describing the genotypes of the tunica and corpus regions is the use of the abbreviations L.I, L.II, and L.III, which represent the outermost layer, the next tunica layer in, and the corpus, respectively; a plant chimeral for ploidy level, or a cytochimera, with a diploid L.I, tetraploid L.II, and tetraploid L.III would be 2-4-4; a variegated chimeral plant possessing a mutant chlorophyll deficient (albino) outer tunica layer overlying normal inner tissue would be labeled a WGG chimera (W indicating white, or albino, tissue; G indicating green tissue); while a plant with the outer layer normal, the next layer in mutant, and the inner corpus normal, would be designated GWG, and so on; such designations are, in the case of chlorophyll chimeras, generally based on the appearance of leaves and other organs produced by derivatives of the apical meristem, and thus may not refer to precise meristem cell layers, since chlorophyll is not synthesized and therefore is not detectable in the tunica and corpus cells of the meristem itself bot >>> ectochimera >>> endochimera >>> mesochimera >>> mutation >>> xenia >>> valence cross >>> Figure 56 >>> Picture 001

chromosome - Chromosome n: a DNA-histone protein thread, usually associated with RNA, occurring in the nucleus of a cell; it bears the genes, which constitute the hereditary material; each species has a constant number of chromosomes; in 1999, a first plant chromosome of the weed Arabidopsis thaliana was genetically decoded; the eukaryotic chromosome is a single DNA molecule complexed with chromatin proteins; it is organized to allow for a hierarchical packing scheme, i. e. (a) DNA helix is wound twice around a core particle of histone proteins, (b) 30 nm fiber: six histone core particles per turn, and (c) loops of 30 nm fibers are formed by attachment of chromatin to the nuclear matrix roughly every 30 to 100 kb; it is important to make the distinction between de-condensed interphase chromosomes and condensed mitotic chromosomes; during interphase, most of the chromosomal material needs to be in an open configuration, to allow for gene expression to occur; during mitosis, the chromatin needs to be condensed; the term was proposed by WALDEYER (1888) for the individual threads within a cell nucleus cyto gene

class (of seed and seed crop): refers to the generations of pedigreed seed and seed crops, such as breeder, select, foundation, registered, and certified which have met the standards prescribed by recognized seed and seed crop certification agencies seed

class-uniform (resolvable design): a resolvable design in which the multiset of block sizes in each parallel class of the resolution is the same stat

clean cultivation: the practice of periodic soil tillage to eliminate all vegetation other than the crop being grown; all plant residues are taken off the field and are not recycled in situ agr meth

cleaning crop: a crop, such as potatoes or sugarbeet, that is used in the crop rotation to help suppress weeds; it does this by shading out the young weeds, which can be finally destroyed by cultivation agr phyt

clinometer >>> hypsometer

C3 plants - C3-Pflanze f: a class of plants in which the first product of CO2 fixation is the 3-carbon compound, phosphoglyceric acid; these are usually temperate plants and are characterized by lower dry matter per unit water used, occurrence of photorespiration and need for greater CO2 concentration as compared to C4 plants; photosynthetically these plants are less efficient than C4 plants; among C3 plants are wheat, rice, barley; biofertilizers for C3 plants include Rhizobium or Azotobacterphys agr

codominant - kodominant adj: a heterozygote that shows fully the phenotypic effects of both alleles at a gene locus gene; in forestry, a tree receiving full light from above, but comparatively little from the sides; such trees usually have medium sized crowns fore

cole (crops) - Kohl m: vegetables of the genus Brassica,including cauliflower, broccoli, cabbage and turnips hort>>> Figure 8

column-complete Latin square: a >>> Latin square is column-complete if each ordered pair of distinct symbols occurs precisely once in consecutive positions in a column of the square stat

column diagram >>> histogram

column-quasi-complete Latin square: a >>> Latin square is column-quasi-complete if each unordered pair of distinct symbols occurs precisely twice in consecutive positions in a column of the square stat

comparative genomic hybridization (CGH) - vergleichende Genomhybridisierung f: a molecular cytogenetic technique that allows detection of DNA sequence copy number changes throughout the genome in a single hybridization meth biot cyto

complementary herbicide: herbicides used in conjunction with a specially designed, herbicide tolerant crop; if a soybean cultivar is genetically modified to have tolerance to an herbicide, the herbicide is considered that soybean cultivar's complementary herbicide; complementary herbicides for herbicide tolerant plants developed with genetic engineering are generally "non-selective" or "broad-spectrum" herbicides; these affect central sites of plant metabolism and are thus effective against a wide range of plants; an herbicide tolerant crop and its respective complementary herbicide constitute an herbicide tolerance system; in this combination, wide-spectrum herbicides like “Roundup” can be applied to kill nearly all weeds without harming the crop biot agr

complete digest:  the treatment of a DNA preparation with an endonuclease for sufficient time for the entire potential target sites within that DNA to have been cleaved biot

complete flower - vollständige Blüte f: a flower that has pistils, stamens, petals, and sepals bot

complete Latin square: a Latin square is complete if it is both row-complete and column-complete stat

complete penetrance - vollständige Penetranz f: the situation in which a dominant gene always produces a phenotypic effect or a recessive gene in the homozygous state always produces a detectable effect gene

complex heterozygous - komplexheterozygot adj: special type of genetic system based on the heterozygosity for multiple reciprocal translocations cyto

complex locus: a cluster of two or more closely linked and functionally related genes constituting a pseudoallelic series gene

component of variance >>> variance

component weight: for each stage of sampling, the component weight is equal to the reciprocal of the probability of selecting the unit at that stage stat

composite: a plant of the immense family Compositae, regarded as comprising the most highly developed flowering plants bot; a mixture of genotypes from several sources, maintained by normal pollination seed

composite cross: a population derived from the hybridization of several parents, either by hand-pollination or by the use of male sterility meth

composite fruit: a seed distribution unit that includes many ovaries connected by fruit walls or other suitable tissue; if the flower basis (receptacle) or other flower components are thick and fleshy (e.g., in strawberry, apple, or fig), it is called false fruit or pseuduocarp bot

composite mixture: breeder seed obtained by mechanically combining seed from two or more strains; the mixture is increased through successive steps in a certified seed program and distributed as a synthetic variety seed

compost - Kompost m: plant and animal residues that are arranged into piles and allowed to decompose agr hort

compound cross: a combination of desirable genes from more than two inbred lines, breeding strains, or varieties meth

compound cyme: a determinate inflorescence where there is secondary branching, and each ultimate unit becomes a simple cyme bot

concatemer: tandem repeats of identical DNA molecules; lamda phage DNA must be concatemer in order to be packaged biot >>> lamda phage

http://wheat.pw.usda.gov/ITMI/Repeats/index.shtml

concatenate: interlocked circles (e.g., plasmids) biot

concave: shaped like the inside of an egg bot

condensation of chromosomes >>> chromosome contraction >>> coiling

condenser: a lens or combination of lenses that gathers and concentrates light in a specified direction, often used to direct light onto the projection lens in a projection system micr

condenser iris diaphragm: the substage iris diaphragm located at the front focal plane of the condenser lens of a microscope; with KOEHLER illumination, the iris lies in a plane conjugate with the rear focal plane of the objective lens micr

conditional mutation: a mutation that has the wild-type phenotype under certain environmental conditions (temperature, age, nutrition) and a mutant phenotype under other conditions gene

conditioned dominance: dominance affected by the presence of other genes or by environmental influence gene

conditioned storage: storage of seed under controlled conditions of temperature and relative humidity seed meth

conditioner: a material or substance added to a fertilizer that keeps it flowing free meth agr

conditioning: the term used to describe the process of cleaning seed and preparing it for market; sometimes called processing seed >>> Table 11

conduction: plasmid mobilization involving cointegrate formation biot

conductivity test: an electrical conductivity test that associates the concentration of leachates from seeds, after soaking in water, to their quality seed

cone - Zapfen m: a fruit with overlapping scales in which seeds are formed fore

cone collection: harvesting of cones after seed maturation but before their dispersal fore hort

confidence belt >>> confidence limit

confidence limit: a term for a pair of numbers that predict the range of values (confidence interval) within a particular parameter stat

confocal optics: a microscope optical system in which the condenser and objective lenses both focus onto one single point in the specimen micr

congenic strain: a variant plant strain that is obtained by backcrossing a donor plant strain to an inbred parental strain for at least eight generations while maintaining by appropriate selection the presence of a small genetic region derived from the donor strain gene

conical divider: an inverted metal cone below a spout from a hopper; the seeds fall over the cone to be evenly dispersed; a series of bugle or riffle dividers separate the seeds into channels seed

conidiophore: a threadlike stalk upon which conidia (spores) are produced; a specialized hypha upon which one or more conidia may bear bot

conidium (conidia pl): any asexual spore formed on a conidiophore bot

conifer - Nadelbaum m: a species of plant that bears it naked seeds in cones (a woody strobilus); their flowers are in cones, and male and flower cones are separate; the oldest (bristlecone pine) and the largest (sequoia) extant organisms belong to this class; it belongs to the Gymnospermae which includes needle-leafed trees such as pines and cypresses; most conifers are evergreen trees and shrubs, e.g., pine, fir, larch, and spruce trees; mesozoic era conifers included redwoods, yews, pines, the monkey puzzle tree (Araucaria), cypress, and Pseudofrenelopsis (Cheirolepidiaceae); towards the end of the Mesozoic, flowering plants flourished and began to overtake conifers as the dominant flora; their unique feature is the inheritance of cytoplasmic DNA (chloroplasts) via pollens bot

coniferous tree >>> conifer

conjugate (of a Latin square): a >>> Latin square obtained by permuting the roles of "rows", "columns", and "symbols" stat

conjugation: a process whereby organisms of identical species, but opposite mating types, pair and exchange genetic material (DNA) gene; in molecular biology, natural process of DNA transfer between bacteria in which the DNA is never exposed; it is insensitive to externally added DNase biot

connective: the tissue joining the two cells of an anther bot

conoidal: nearly conical bot

consanguinity >>> coancestry

consensus sequence: if a particular nucleotide sequence is always found with only minor variations, then the usual form of that sequence is called consensus sequence; the term is also used for genes that encode the same protein in different organisms gene

conservation: maintenance of environmental quality and resources seed

conservation tillage: seed bed preparation systems that have about 30 % or more of the residue cover on the surface after planting agr

constitutive heterochromatin: the material basis of chromosomes or segments that exhibit heterochromatic properties under most conditions (e.g., centromeric or telomeric heterochromatin) cyto

constitutive mutation: causes genes that usually are regulated to be expressed without regulation gene

constriction - Einschnürung f: an unspiralized segment of fixed position in the metaphase chromosomes (nucleolar ~ , primary or centric ~ , secondary ~ ) cyto

containment: measures taken to prevent release of recombinant DNA molecules into the natural environment; biological and physical methods are applied biot

contiguous (contig) map: the alignment of sequence data from large, adjacent regions of the genome to produce a continuous nucleotide sequence across a chromosomal region biot

continuous culture: an in vitro suspension culture continuously supplied with nutrients by the inflow of fresh medium; the culture volume is normally constant biot >>> closed continuous culture

continuous scale: a scale for scoring quantitative data for which the number of potential values is not predefined and is potentially limitless (e.g., seed weight in grams) stat

continuous variation: variation in the expression of inherited traits in which a series of nondiscrete, intermediate types, which cannot be divided into separate categories, connect the extremes with no obvious breaks between them gene >>> quantitative character

contour ploughing: a system of ploughing in which the furrows follow the land contours in order to minimise soil erosion meth agr

contrasting genetic character: a character with marked phenotypic differences gene

control: an economic reduction of crop losses caused by plant diseases phyt agr

controlled breeding: the reproduction of desired characteristics >>> breeding

controlling element: a mobile (autonomous or nonautonomous) genetic component capable of producing an unstable, mutant target gene gene

controlling gene: a gene that is involved in turning on or off the transcription of structural genes; two types of genetic elements exist in this process; a regulator and a receptor element; the receptor elements is one that can be inserted into a gene, making it a mutant, and can also exit from the gene; both of these functions are under control of the regulator element gene

control pollination: in horticulture and forestry, to purposely pollinate the female flowers of a tree with pollen from a known source; usually the flowers are isolated from undesirable pollen by covering them with a pollen-tight cloth or paper bag before they are receptive; it is a way to produce full-sib families meth hort fore

convariety (convar.): a group of similar cultivars within a variable species or hybrids between two species; the term has now been replaced in most cases by the word "group" tax

convergence: the evolution of unrelated species occupying similar adaptive areals, resulting in structures bearing a superficial resemblance evol

convergence breeding: a breeding method involving the reciprocal addition to each of two inbred lines of the dominant favorable genes lacking in one line and present in the other; backcrossing and selection are performed in parallel, each of the original lines serving as the recurrent parent in one series meth >>> Figure 31

convergence-divergence selection: a breeding scheme in which selection of promising genotypes is made in a bulk population at different locations followed by massing of selection and allowing mating among them in a pollination field; the harvested bulk seeds constitute the basis for the next propagation cycle meth

convergent crossing >>> convergence breeding

convex: shaped like the outside of an egg bot

coorientation >>> centromere orientation

COP >>> coefficient of parentage

copper (Cu): a malleable ductile metallic element having a characteristic reddish brown color; as a trace element it is needed by plants; deficiency can cause severe problems of growth; as iron efficiency, copper efficiency is genetically controlled (e.g. on rye chromosome arm 5RL a dominant gene and/or gene complex is located, increasing Cu efficiency not only in rye but also in wheat when the gene is transferred into the recipient) chem phys >>> white leaf disease >>> mugeinic acid >>> chelate

coppice: natural regeneration originating from stump sprouts, stool shoots, or root suckers fore hort

coppice-of-two-rotations method: a coppice method in which some of the coppice shoots are reserved for the whole of the next rotation; the rest being cut fore

coppice method: a method of regenerating a forest stand in which the cut trees produce sprouts, suckers, or shoots fore

coppice selection method: a method in which only selected shoots of usable size are cut at each felling, leading to uneven-aged stands fore

coppice shoot: any shoot arising from an adventitious or dormant bud near the base of a woody plant that has been cut back fore hort

coppice-with-standards method: regenerating a forest stand by coppicing; selected trees grown from seed are left to grow to larger size than the coppice beneath them; the method is used to provide seeds for natural regeneration of standards in subsequent rotations fore

copulation: the fusion of sexual elements gene

copy-choice hypothesis: the interpretation of intrachromosomal genetic recombination that is not regarded as a physical exchange of preformed genetic strands gene

copy error: an error in the DNA replication process giving rise to a gene mutation gene

copy gene: genetic material incorporating the genetic code for a desirable trait which has been copied from DNA of the donor to the host organism biot

copy number: the number of molecules per genome, of a plasmid or a gene, that a cell contains gene biot

cordage: ropes agr

cordon: an extension of the grapevine trunk, usually horizontally oriented and trained along the trellis wires; it is considered permanent (or perennial) wood hort

core collection: the basic sample of a germplasm collection; it is designed to represent the wide range of diversity in terms of morphology, geographic range, or genes; it contains, with a minimum of repetitiveness, the genetic diversity of a crop species and its wild relatives; it is not intended to replace existing gene banks collections but to include the total range of genetic variation of a crop in a relatively small and manageable set of germplasm accessions meth seed

corepressor: a metabolite that in conjugation with a repressor molecule binds to the operator gene present in an operon and prevents the synthesis of a repressible enzyme gene

coriaceous: leathery bot

cork - Kork n: in woody plants, a layer of protective tissue that forms below the epidermis bot

cork cambium >>> phellogen

cork layer - Korkschicht f: layer of dead protective tissue between the bark and cambium in woody plants bot

http://rootgenomics.missouri.edu

corm(us): an underground storage organ formed from a swollen stem base, bearing adventitious roots, and scale leaves; it may function as an organ of vegetative reproduction or in perennation bot

corn - Korn n: the edible seed of cereal plants other than maize bot >>> caryopsis

corn - Mais m: US maize

corn bran: the fibrous outer coating of the maize kernel, regarded as a low-grade food for cattle or a high-grade food for humans bot

corneous: it refers to hard, vitreous, or horny endosperm in cereal grains bot agr

corn-loft >>> granary

corolla: a collective term for all the petals of a flower; a nonreproductive structure; often arranged in a whorl; encloses the reproductive organs bot

correlation - Korrelation f: the degree to which statistical variables vary together; measured by the correlation coefficient, which has a value from zero (no correlation) to –1 or +1 (perfect negative or positive correlation) stat

correlation breaker >>> outlier

correlation coefficient - Korrelationskoeffizient m: a measure for the degree of association between two or more variables in an experiment; it may range in value from –1 to +1 stat >>> correlation

corresponding gene pair: a pair of genes in a parasite that corresponds with a pair of genes in a host, which function together to bring about a specific outcome phytcortex >>> rind

corymb: a racemose inflorescence in which the lower pedicels are longer than the upper so that the flower lies as a dome or dish, and the outline is roundish or flattish bot

cosmid - Kosmid n: a synthetic word derived from the designations cos and plasmid; a cosmid is a plasmid (e.g., pBR322) with so-called cos-sites of the DNA; they offer the chance of incorporation of alien DNA fragments of sizes between 32-45 kb gene >>> cos site

cosmopolite: plant of worldwide distribution eco

cosmopolitan cultivar(s): cultivars that have a wide geographical and environmental range agr eco

cos site: the site of the circular form of phage lamda or others that is cleaved by the terminase to generate the cohesive 12 bp 5' overhang ends of the linear phage as it is packaged into the capsid biot >>> cosmid >>> lamda phage

cosuppression: silencing of a gene by addition of transgenic DNA copies or infection by a virus; this term, which can refer to silencing at the post-transcriptional (PTGS) or transcriptional (TGS) level, has been primarily adopted by researchers working with plants biot >>> post-transcriptional silencing

cotransformation: an event of two plasmids entering the same cell by transformation biot

Cot curve: graphic representation of the progress of a (liquid) hybridization experiment; used to determine the complexity of DNA mixtures (e.g., the size of the genome) gene biot

Cot value: an expression for the rate of DNA renaturation (annealing-reannealing); DNA renaturing at low Cot is composed of highly repetitive sequences and DNA renaturing at high Cot values is minimal or nonrepetitive gene biot

cotyledon - Keimblatt n: the leaf-forming part of the embryo in a seed; it may function as a storage organ from which the seedling draws food, or it may absorb and pass on to the seedling nutrients stored in the endosperm; once it is exposed to light it develops chlorophyll and functions photosynthetically as the first leaf bot >>> Table 16

cotyledonary node: the point of attachment of the cotyledons to the embryonic axis bot

coulter: a sharp blade or wheel attached to the beam of a plough, used to cut the ground in advance of the ploughshare agr

coumarin - Kumarin n: a white crystalline compound (C9H6O2) with a vanilla-like odor; it gives sweetclover its distinctive odor; it is also known as a chemical growth inhibitor that has germination-inhibiting capability phys

couple method (of breeding): a breeding method exclusively used in breeding of allogamous plants; from an original population (e.g., of sugarbeet), single plants are selected and, subsequently, pair-wise crossed, preventing unwished pollination; the crossing partners should be as similar as possible in spite of color, growth habit, etc.; the offspring is grown in separate plots during the following year; the selection of individuals from the plots and a repeated pair-wise crossing can be realized during the fourth year; during the fifth year offspring is grown in plots and again selected for progeny testing meth >>> Figure 41 >>> Table 35

coupling of factors: linkage in which both dominant alleles are in the one parent gene >>> linkage

covariance analysis: an analysis of the mean of the product of the deviation of two variates from their individual means; it measures the interrelationship between variables stat

coverage error: in an estimate results from the omission of part of the target population stat

cover crop: a crop grown between orchard trees or on fields between the cropping seasons of a main crop, to protect the soil against erosion and leaching and for improvement of soil agr

C3 pathway: most common pathway of carbon fixation in plants; this photosynthesis produces at first a 3-carbon (C3) compound (phosphoglyceric acid); in C3 plants, about 25 % of the net carbon uptake is reevolved immediately in photorespiration phys

C4 pathway: a carbon fixation found in some plants that have high rates of growth and photosynthesis and that are adapted to high temperatures, strong light, low carbon dioxide levels, and low water supply; this photosynthesis produces at first a 4-carbon (C4) compound (phosphoenolpyruvate, PEP); in C4 plants, photorespiration is suppressed to a very large extent due to the presence of a very efficient C2-concentrating mechanism phys

C3 plants: a class of plants in which the first product of CO2 fixation is the 3-carbon compound, phosphoglyceric acid; these are usually temperate plants and are characterized by lower dry matter per unit water used, occurrence of photorespiration and need for greater CO2 concentration as compared to C4 plants; photosynthetically these plants are less efficient than C4 plants; among Ce plants are wheat, rice, barley; biofertilizers for C3 plants include Rhizobium or Azotobacterphys agr

C4 plants: found principally in hot climates whose initial fixation of carbon dioxide in photosynthesis is by the Hatch Slack Kortshak (HSK) pathway; the enzyme responsible is PEP carboxylase (carboxylates phosphoenolpyruvate, PEP, to give oxaloacetate), whose products contain four carbon atoms; subsequently the carbon dioxide is released and refixed by the Calvin Benson cycle; the presence of the HSK pathway permits efficient photosynthesis at high light intensities and low carbon dioxide concentrations; most species of this type have little or no photorespiration; among C4 plants are sugarcane, maize, tropical grasses; Azospirillum is the main biofertilizer for C4 plants phys

crease: the fold on a cereal grain bot

criss-crossing: a continuous, rotational crossbreeding system alternately using males or pollinators of two different breeds; this system is simple to manage and breeds its own replacements; it utilizes the benefit of hybrid vigor; compared to the common F1, some hybrid vigor can be lost, but that loss is more than compensated for by reduced management effort and cost meth

criss-cross inheritance: the transmission of a gene from mother to son or father to daughter gene >>> criss-crossing

cristae >>> mitochondrion

critical difference: a value indicating least significant difference at values greater than which all the differences are significant stat

critical set (in a Latin square): a set of entries in a square grid which can be embedded in precisely one >>> Latin square, with the property that if any entry of the critical set is deleted, the remaining set can be embedded in more than one Latin square stat

crop: a plant species expressly cultivated for use agr >>> Table 35 >>> crop plant

crop calendar: a list of the standard crops of a region in the form of a calendar giving the dates of sowing and the agricultural operations and various stages of their growth in years of normal weather agr meth

crop divider (at the harvester): separates the standing crop from the material being cut agr

crop evolution: the adaptation of a crop over generations of association with humans evol

cropping pattern: the yearly sequence and spatial arrangement of the crops or of crops and fallow on a given area; it includes sequential or multiple cropping, intercropping, mixed cropping, relay cropping etc., e.g., rice followed by wheat, maize followed by wheat followed by greengram agr meth >>> crop rotation

crop plant - Kulturpflanze f: a plant expressly cultivated for use; the majority of crops can be classified as (1) root and tuber crops (potato, yams), (2) cereals (e.g., wheat, oats, barley, rye, rice, maize), (3) oil and protein crops (rapeseed, pulses), (4) sugar crops (sugarbeet, sugarcane), (5) fiber crops (cotton, jute), or (6) forage crops (grasses, legumes); agronomic crops can be classified as (a) green manure crops, (b) cover crops, (c) silage crops, or (d) companion crops; about 2 % of the 250,000 higher plant species are used in agriculture, horticulture, etc.(about 1,700-2,000); economically, the most important families are the legumes and the grasses, which account for more than a quarter of the total species; they are followed by Rosaceae, Compositae, Euphorbiaceae, Labiatae, and Solanaceae, all with more than 100 taxa; among the families with 50 to 100 crop species, Liliaceae, Agavaceae, and Palmae are worth mentioning, whereas more than 50 % of the families have fewer than ten crop species agr >>> Tables 1, 35 >>> crop plants

crop residue - Pflanzenrückstand m: that portion of a plant left in the field after harvest (maize stalk or stover, stubble) agr

crop rotation - Fruchtfolge f: the alternation of the crop species grown on a field; usually this is done to reduce the pest and pathogen population or to prevent one-track exhaustion agr

crop ferality: feral plants are often semi-domesticated, escaped from the field a long time ago, having been domesticated and now  growing wild (Cyperus rotundus, Cynodon dactylon, Echinochloa crus-galli, Echinochloa colonum, Eleusine indica, Sorghum  halepense, Imperata cylindrica, Portulaca oleracea, Chenopodium album, Digitaria  sanguinalis, Convolvulus arvensis, Avena fatua, Amaranthus hybridus, Amaranthus spinosus, Cyperus esculentus, Paspalum conjugatum, Rottboellia exaltata); but growing wild has to be circumscribed properly: only in exceptional cases a feral crop really grows in the wild, usually such populations stick to ruderal places, to disturbed habitats, in the dense competitive environment of natural habitats such as dry meadows it is very difficult for weeds and feral plants to establish permanently; weeds and feral crops are perfectly adapted to life conditions in anthropogenically disturbed areas; thus, surviving strategies of weeds and feral crops are very diverse (germination requirements, discontinuous germination, rapid growth through vegetative phase to flowering, continuous seed production for as long as growing conditions permit; self-compatible but not completely autogamous or apomictic; when cross-pollinated, unspecialized visitors or wind-pollinated; very high seed output under favourable environmental circumstances, adaptations for short- and long-distance dispersal, if a perennial, vigorous vegetative reproduction or regeneration from fragments etc.) agr biot

crop tree: a tree identified to be grown to maturity and which is not removed from the forest before the final harvest cut; it is usually selected on the basis of its location with respect to other trees and its quality fore meth

cross: bringing together of genetic material from different individuals in order to achieve genetic recombination meth

cross back >>> backcrossing

crossability: the ability of two individuals, species, or populations to cross or hybridize bot eco

crossbred >>> self

crossbreeding: outbreeding or the breeding of genetically unrelated individuals; this may entail the transfer of pollen from one individual to the stigma of another of a different genotype meth >>> Figure 7 >>> Picture 013 >>> Table 35

crossbreeding barrier: a pre- and/or postfertilization condition (i.e., progamous or postgamous incompatibility) that prevents or reduces crossbreeding or any form of gene transfer; it is caused by genetic, environmental, physical, or chemical influences >>> Table 35

cross classification - Kreuzklassifizierung f: classification according to more than one attribute at the same time stat

cross coancestry: refers to the average of the elements in a coancestry matrix excluding the self-coancestry on the diagonal;  thus the expected inbreeding following random mating in a population without inbreeding stat meth >>> pairvise coancestry >>> group coancestry  >>> coancestry

cross-fertilization: the fusion of male and female gametes from different genotypes or individuals of the same species, as base of genetic recombination bot >>> allogamy >>> cross-pollination >>> Table 35

cross-hybridization: in biotechnology, the hydrogen bonding of a single-stranded DNA sequence that is partially but not entirely complementary to a single-stranded substrate; often, this involves hybridizing a DNA probe for a specific DNA sequence to the homologous sequences of different species biot

crossing barrier: any of the genetically controlled mechanisms that either entirely prevent or at least significantly reduce the ability of individuals of a population to hybridize with individuals of other populations gene >>> crossbreeding barrier

crossing block: a crop plant nursery containing the parental stocks for a breeder's crossing program meth

crossing group(s): any group of individuals that comprises a unique set of parents: (1) diallel crossing group—controlled crosses are made between each pair of parents in the group but crosses with parents outside the group are excluded, (2) factorial crossing group—a limited number of parents are used as male testers in controlled crosses with an unlimited number of female parents, (3) open-pollinated crossing group—all parents in a breeding population are included in a progeny test or series of tests meth fore hort >>> Table 35

crossing-over: the exchange of genetic material between homologous chromosomes by breakage and reunion; it occurs during pairing of chromosomes at prophase I of meiosis; the temporary and visible joins between chromosomes during crossing-over are called chiasmata gene cyto >>> Figure 24

crossing-over map: a genetic map made by utilizing crossing-over frequencies as a measure of the relative distances between genes in one linkage group (chromosome) gene

cross(ing)-over unit: a 1 % crossing-over value between a pair of linked genes gene >>> MORGAN unit

cross-inoculation: inoculation of one legume species by the symbiotic bacteria from another agr

cross-pollinating crop >>> crossbreeding >>> cross-pollination >>> xenogamy >>> Table 35

cross-pollination: the transfer of pollen from the stamen of a flower to the stigma of a flower of a different genotype but usually of the same species, with subsequent growth of the pollen tube bot >>> allogamy >>> Picture 013 >>> Table 35

cross-protection: plant protection conferred on a host by infection with one strain of, for example, a virus that prevents infection by a closely related strain phyt

cross-resistance: resistance associated with a change in one genetic factor that results in resistance to different chemical pesticides that were never applied phyt

cross-sterility: the failure of fertilization because of genetic or cytological conditions (incompatibility) in crosses between individuals >>> crossing barrier >>> Table 35

crown: the stem-root junction of a plant (e.g., the overwintering base of an herbaceous plant) hort; the term is also used for the treetop bot fore

crown cover: the canopy of green leaves and branches formed by the crowns of all trees in a forest fore

crucifer: a plant belonging to the Brassicaceae or mustard family, a large dicotyledonous family of important crop and ornamental plants (turnip, cabbage, etc.) bot >>> Figure 8

crust: a surface layer of soil that becomes harder than the underlying horizon when dry agr

cryoability: the ability of plant material (seeds, tissue, organs) to preserve or store under very low temperatures, usually in liquid nitrogen (–196°C) phys

cryobank: the preservation or storage under very low temperatures, usually in liquid nitrogen (–196°C) meth seed

cryodamage: damage caused by exposure to cold conditions agr

cryopreservation: the preservation or storage in very low temperatures, usually in liquid nitrogen (–196°C) meth

cryoprotectant: a chemical, which is used to protect seeds, cultured material, tissue, organs or cells from the low temperature in cryopreservation (e.g., glycerol) prep

cryoscopy: a technique for determining the molecular weight of a substance by dissolving it and measuring the freezing point of the solution meth

cryostat: a device designed to provide low-temperature environments in which experiments may be carried out under controlled conditions prep

cryptochrome >>> photomorphogenesis

cryptogam: a plant (e.g., fern) that reproduces by means of spores rather than seeds bot

cryptogam(ous): reproduction by spores or gametes rather than seeds bot

cryptogams >>> cryptogam(ous)

cryptomeric gene >>> cryptomerism

cryptomerism: the phenomenon that a gene or an allele does not show a phenotypic effect unless it is activated by another genetic factor, which leads to a sudden change of qualities in the progeny, not recognized among the ancestors gene

crystallography: the determination of, for example, the protein structure; the protein is crystallized and the crystals examined using X rays; the diffraction angles of the X rays are used to compute the relative positions of components of the protein, and thus its structure phy

CsCl2 gradient: a method used to separate DNA or phages according to buoyant density biot

CSSA: Crop Science Society of America

CTD >>> canopy temperature depression

cuckoo chromosome: an alien chromosome that shows a preferential transmission during generative reproduction; found in certain wheat-Aegilops crossing progenies cyto

cuckoo gene: it refers to a gene conferring preferential transmission from the maternal parent, e.g., in Lablab purpureus (KONDURI et al., 2000) gene

cucullate: hood- or cowllike in form bot

culled >>> off-grade

culling: the postharvest removal of pathogen-infected or damaged fruit, seeds, or plants by screening procedures; the culled or off-graded material can later be individually analyzed or discarded meth

culm - Halm m: the jointed stem in cereals, grasses, or sedges; filled with pith or solid bot

cultigen: a cultivated plant or group of plants for which there is no known wild ancestor (e.g., maize Zea mays) bot tax

cultivar - Sorte f: a contraction of “cultivated var iety” (abbreviated cv.); refers to a crop variety produced by scientific breeding or farmer’s selection methods; after International Code of Nomenclature for Cultivated Plants (ICNCP-1995): "cultivar" is synonymous with "Sorte" (German), "variety" (English), or "variété" (French); Chapter 3: "A cultivar is a taxon that has been selected for a particular attribute or combination of attributes, and that is clearly distinct, uniform and stable in its characteristics and that, when propagated by appropriate means, retains those characteristics." bot >>> variety

cultivar identification system: a classification system based on sequence-tagged microsatellite loci analysis with fluorescent primers and suitable computer software; allows unequivocal identification of varieties, paternity testing, and duplicate identification meth biot

cultivar mixture: a mixture of different varieties in order to improve the environmental adaptability or the resistance to pathogens seed

cultivation: the art or process of agriculture agr

cultivator - Kultivator m: an implement drawn between rows of growing plants to loosen the earth and destroy weeds agr

culture - Kultur f: a growth of one organism or of a group of organisms for the purpose of production, trade, and utilization or for experiments agr

culture collection: a collection of cultures of more or less defined or characterized viruses, bacteria, and other organisms; usually used for reference and comparison with new isolates phyt

culture medium: medium on or in which tissues, organs, or cells are cultured; supplies the mineral and hormonal requirements for the growth meth biot

culture tube: a tube in which tissue, organs, cells, or organisms are cultured prep

cumulative genes: polymeric non-allelic genes gene

cupule: a cup-like structure at the base of some fruits bot

current agriculture: science-based area-specific agriculture which makes use of mineral fertilizers, organic manures, bioinoculants and plant protection chemicals adopting best management practices; it is also termed as conventional agriculture agr >>> agriculture

curry powder: in India, any good cooks make their own curry powders, and there are as many recipes as there are good cooks; m ost curry powders contain about 25% >>> turmeric (Cucurma domestica), 25% >>> coriander (Coriandrum sativum) seeds, and various amounts of >>> cumin (Cuminum cyminum) seeds, >>> cardamoms (Elettaria cardomomum), >>> fenugreek (Trigonella foenum-graecum) seeds, >>> chillies (Capsicum annum), >>> ginger (Zingerber officinale), >>> black pepper (Piper nigrum), and dill (Anethum graveolens) seeds hort

cushion plants: have small, hairy, or thick leaves borne on short stems and forming a tight hummock bot

cut-and-come-again: applied to any plant that is cut or sheared after flowering and blooms again (e.g., Petunia spp., pansy) hort

cut flowers: flowers that are cut off the plant and used as decoration hort

cuticle: a thin, waxy, protective layer covering the surface of the leaves and stems bot

cutin: the complex mixture of fatty-acid derivatives with waterproofing qualities of which the cuticle is composed bot

cutinize: to impregnate a cell or a cell wall with cutin, a complex fatty or waxy substance, which makes the cell more or less impervious to air and moisture bot

cutout: the occurrence of physiologically indeterminate growth (e.g., in cotton) agr

cut surface >>> cutin >>> cutinize

cutting:a section of a plant that is removed and used for propagation; cuttings may consist of a whole or part of a stem (leafy or nonleafy), leaf, bulb, or root; a root cutting consists of root only; other cuttings have no roots at the time they are made and inserted; as opposed to division, a kind of propagation that consists of part of the crown of a plant or of its above-ground portion and roots; several  types of cuttings can be taken from the parent stock, which depends on the point on the parent stock the cutting is taken from; four major categories of cuttings are (1) stem cuttings, (2) leaf cuttings, (3) leaf-bud cuttings, and (4) root cuttings; stem cuttings are severed twigs that have been placed into growing medium and encouraged to develop roots; stem cuttings are broken down into sub-classes consisting of hardwood, semi-hardwood, softwood, and herbaceous cuttings; hardwood cuttings are taken from the current seasons growth; this portion of the tree offers young tissue; cuttings should be taken during the winter season; semi-hardwood cuttings are produced from woody, broadleaf evergreens, and leafy summer cuttings; they are taken from partially matured portion of the plant, usually taken during the summer growing months just after new shoot development, and partially matured; softwood cuttings are taken from new, soft, succulent spring growth from either deciduous or evergreen species; although softwood cuttings usually root easier and quicker than other cuttings, they also require more labor and equipment; this is because the cuttings are made with their leaves still attached; herbaceous cuttings are taken from succulent, herbaceous plants; this type of cutting roots fast, but is not used in forestry practice; leaf cuttings are not used extensively in forestry applications; this form of propagation utilizes the leaf to promote new plant growth; a root and shoot will form and develop, from the leaf cutting, into a new plant; the original leaf cutting does not remain as part of the new formed plant; leaf-bud cuttings is not used extensively in forestry applications; the leaf-bud cutting includes the leaf itself, petiole, and a small piece of stem with the axially bud; this form of cutting propagation is useful when material is scare, because the same amount of stock will produce twice as many new plants as that of stem cuttings; root cuttings, which are used in forestry propagation, should be taken from the young plant stock during the winter and spring months to ensure that they are saturated with stored foods; this time frame also prevents cutting during the time the parent plant is rapidly expanding shoot growth; cutting during active expansion will take food stores away from the root system hort fore meth

cutting cycle: the planned time interval between major harvesting operations in the same tree stand; the term is usually applied to uneven-aged stands; e.g., a cutting cycle of 10 years means that every 10 years a harvest would be carried out in the stand fore

cv. >>> cultivar

C value - C-Wert m: the DNA quantity per genome (i.e., per chromosome set); the content of diploids is referred to as the 2C; haploid cells contain the 1C amount of DNA cyto

cybrid: the hybrid formed from the fusion of a cytoplast and a whole cell; the cytoplast may transmit cytoplasmic components independently of the cell genome bot

cyclical parthenogenesis: a life history in which a sequence of apomictic generations is followed by amphimictic generations bot

cyclic design - zyklische Versuchsanlage f: an incomplete-block design is a cyclicdesign if its blocks can be partitioned into sets of blocks such that each set is a thin cyclic design stat >>> an incomplete-block design

cycling: a round of recombination, testing and selection; it may often refer to the mating breed

cycling strategy: choice of methods of recombination, testing and selection in repeated cycling meth breed >>> breeding strategy

cyclohexanedione(s) (CHDs): as aryloxyphenoxypropionates (APPs), it is a specific graminicide herbicide; chloroplastic acetyl CoA-carboxylase (ACCase) is the target of the chemical reaction; with the wide application resistance to these compounds became a worldwide, increasing problem phyt phys

cycloheximide (actidione): an antibiotic from Streptomyces griseus; antibacterial and antifungal biot

cyme: an inflorescence in which each axis ends in a flower bot

cysteine (Cys): an aliphatic, polar alpha-amino acid that contains a sulfydryl group chem phys

cytochimera: different tissues or parts of them differ in chromosome number cyto >>> chimera >>> Figure 72

cytochrome (Cyt) - Zytochrom n: an iron-containing pigment that plays a major role in respiration; more detailed, one of a group of haemoproteins, which are classified into four groups designated a, b, c, and d; they function as electron carriers in a variety of redox reactions in virtually all aerobic organisms phys

cytodifferentiation: the sum of processes by which during the development of the individual the zygote specialized cells, tissue, and organs are formed cyto

cytogamy - Zytogamie f: the fusion or conjugation of cells cyto

cytogenetic map - zytogenetische Karte f: a map showing the locations of genes on a chromosome, i. e. the visual appearance of a chromosome when stained and examined under a microscope; particularly important are visually distinct regions, called light and dark bands (or colored bands), which give each of  the chromosomes a unique appearance cyto gene

http://www.desicca.de/Rye gene map

cytogenetics - Zytogenetik f: scientific discipline that combines cytology with genetics gene cyto

cytogenic male sterility >>> cytoplasmic male sterility

cytogony: the reproduction by single cells cyto

cytohet: a cell containing two different cytoplasmic genomes (e.g., mitochondria) that differ in one or more genes contributed by two parents; thus, the individual is cytoplasmatically heterozygous gene

cytokinesis - Zytokinese f: during the division of a cell, the division of the constituents of the cytoplasm; it usually begins in early telophase with the formation of a cell plate, which is assembled within the phragmoplast across the equatorial plane; the phragmoplast is a complex array of GOLGI-derived vesicles, microtubule, microfilaments, and endoplasmatic reticulum that assembles during the late anaphase and is dismantled upon completion at the new wall cyto

cytokinin - Zytokinin n: one of a group of hormones, including kinetin, that act synergistically with auxins to promote cell division but, unlike auxins, that promote lateral growth phys

cytology - Zytologie f: the branch of biology dealing with the structure, function, and life history of the cell cyto

cytolysis - Zytolyse f: breaking up or solution of the cell wall cyto

cytomixis - Zytomxis f: the extrusion or passage of chromatin from one cell into the cytoplasm of an adjoining cell cyto

cytoplasm - Zytoplasma n: the part of a cell that is enclosed by the plasma membrane, but excluding the nucleus cyto

cytoplasmic inheritance - zytoplasmatische Vererbung f: a non-Mendelian (extra-chromosomal) inheritance via genes in cytoplasmic organelles (mitochondria, plastids) gene

cytoplasmic male sterility (CMS): pollen abortion due to cytoplasmic factors, which are maternally transmitted, but which act only in the absence of pollen-restoring genes; this type of sterility can also be transmitted by grafting gene >>> Figure 2

cytoplasmon - Zytoplasmon n: all cytoplasmic hereditary constituents of a cell excepting those localized in the plastids and mitochondria cyto

cytoplasm-restorer >>> cytoplasmic male sterility

cytoplast - Zytoplast m: the cytoplasm as a unit, as opposed to the nucleus bot

cytosine (C) - Zytosin n: a pyrimidine base that occurs in both DNA and RNA chem gene

cytosol - Zytosol n: the water-soluble components of cell cytoplasm, constituting the fluid portion that remains after removal of the organelles and other intracellular structures bot

cytostatic - zytostatisch adj: any physical or chemical agent capable of inhibiting cell growth and cell division phys

cytotaxonomy - Zytotaxonomie f: the study of natural relationships of organisms by a combination of cytology and taxonomy tax >>> Table 17

cytotype - Zytotyp m: any variety of a species whose chromosome complement differs quantitatively or qualitatively from the standard complement of that species cyto

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