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S0: a symbol used to designate the original selfed plant meth
S1, S2, S3, etc.: the representation for continued selfing (self-fertilization) of plants; S1 designates the generation
obtained by selfing the parent plant, S2 the generation obtained by selfing the S1 plant, etc. meth
S1 nuclease: a nuclease that cuts single-stranded DNA and RNA; used for S1 protection experiments in transcript mapping biot
saccharide: an alternative term for sugar chem phys
saccharose: a sweet, crystalline substance, C12H22O11, obtained from the juice or sap of many plants (e.g., from
sugarcane and sugarbeet) chem phys
sacrificial crop: crop planted to distract pests safely agr
safranin >>> GRAM’s stain
SAGE >>> serial analysis of gene expression
S-allele:
an allele of a gene controlling incompatibility in many allogamous plants; alleles present in both style and pollen are referred to as matching S-alleles; S-alleles usually belong to a series of multiple alleles gene
sagittate: arrow-shaped bot
salicin >>> glucoside
salicylic acid:
a phenolic substance, which is accumulated in many plants as part of the defence response; it is shown, in some plants, to be necessary for the accumulation of pathogenesis-related proteins; treatment of plants with salicylic acid can induce resistance biot
saline soil: a soil containing enough salts to reduce plant fertility agr >>> crop rotation
salinization - Versalzung f: the accumulation of soluble salts at the surface or at some point below the surface of the soilprofile
to levels that have negative effects on plant growth and/or on soils; this occurs due to water evaporation leaving behind salts that were dissolved in soil water agr eco
Salmon procedure:
a method for producing haploids in hexaploid wheat; “Salmon” is a name of an alloplasmic wheat variety carrying a 1RS.1BL chromosome translocation together with cytoplasm of Aegilops kotchyi; the interaction of cytoplasmically genetic determinants with, possibly, a parthenogenesis-inducing gene on chromosome arm 1RS of rye results in haploid progeny meth >>> Figures 17, 26 >>> Table 7
saltation: a mutation occurring in the asexual state of fungal growth, especially one occurring in vitro culture phyt
saltational speciation >>> quantum speciation
samara: a fruit similar to an achene except that the entire seed coat is tightly fused with the pericarp (e.g., ash, elm, tree of heaven, etc.) bot >>> winged fruit
sample: a finite series of observations taken from a population meth stat
sample size:
the number of experimental units on which observations are considered; it may be less than the number of observations in a data-set, due to the possible multiplying effects of multiple variables and/or repeated measures within the experimental design stat
sampling: the method by which a representative sample is taken from a seed lot or something else meth
sampling error: variability due to the limited size of the sample stat
sanitation: plant disease control involving removal and burning of infected plant parts and decontamination of tools, equipment, etc. phyt
sanitation cut:
a cutting made to remove trees killed or injured by fire, insects, fungi, or other harmful agencies, for the purpose of preventing the spread of insects or disease phyt fore
sap: the exudate from ruptured tissues emanating from the vascular system or parenchyma bot
saponin:
any member of a class of glycosides that form colloidal solutions in water and foam when shaken; it occurs in many different plant species; in cereals, only oats are known to produce these compounds; in oats, the resistance to infection by the take-all fungus, Gaeumannomyces graminis var. tritici, has been attributed to the family of antifungal saponins known as avenacins, which are present in roots chem phys
saprophyte: an organism that lives on or in dead or decaying organic matter bot
sapwood: the living, softer part of the wood between the inner bark and the heartwood bot fore
sarment: a slender running stem bot >>> runner
sarmentous plant >>> runner
SAT chromosome >>> satellite(d) chromosome
satellite: a distal segment of a chromosome that is separated from the rest of the chromosome by a chromatic filament cyto
satellite(d) chromosome:
each chromosome with a secondary constriction; this constriction divides a satellite part from the rest of the chromosome (arm) cyto
satellite DNA:
a highly repetitive DNA, composed of repeated hepta- to deca-nucleotide sequences; DNA of different buoyant density; a minor DNA fraction that has sufficiently different base composition from the bulk of the DNA in order to separate distinctly during cesium chloride density gradient centrifugation; it can derive from nucleus, plastid, or mitochondrial DNA biot
http://wheat.pw.usda.gov/ITMI/Repeats/index.shtml
SAT-zone: the secondary constriction of a satellite chromosome cyto >>> nucleolar zone
savanna: a plain characterized by coarse grasses and scattered tree growth eco
scab: a general term for any unrelated plant disease in which the symptoms include the formation of dry, corky scabs phyt
scald: a necrotic condition in which tissue is usually bleached and has the appearance of having been exposed to high temperatures phyt
scale: any thin, scarious body, usually a degenerated leaf bot
scale stick:
a flat stick, similar to a yardstick, which is calibrated so log volumes can be read directly when the stick is placed on the small end of the log of known length meth fore
scalping: the removal of material larger than the crop seed during the processing of seeds seed
scanning electron microscopy:
a microscope used to examine the surface structure of biological specimens; a three-dimensional screen image is acquired through focusing secondary electrons emitted from a sample surface bombarded by an electron beam micr
SCAR >>> sequence characterised amplified region
scarification:
the process of mechanically abrading a seed coat to make it more permeable to water; this process may also be accomplished by brief exposure to strong acids (sulfuric acid); it may enhance germination seed
scatter diagram: a diagram in which observations are plotted as points on a grid of x- and y-coordinates to see if there is any correlation stat
SCE >>> sister chromatid exchange
“Schiave”: collectively refers to grapevine cultivars presently grown on the Southern and Northern slopes of the Eastern Alps and
bearing different names, such as Schiava, Trollinger, Rossara, Rossola, Geschlafene, Gansfüsser, Urban, etc.; their common origin has been suggested by historic, linguistic and ampelographic considerations;
however, a dendrogram constructed from an AFLP analysis of the 33 Schiave cultivars shows different and in some cases relevant degrees of genomic dissimilarity; the analyzed cultivars cluster into at least
five taxonomic groups with specific geographic distribution along the valleys of Valtellina, Bergamo and Brescia and those of South Tyrol and Swabia; it is concluded that the common definition
''Schiave'' refers to a similar cultivation practice in contiguous regions rather than to a common genetic background (FOSSATI et al. 2001) hort
SCHIFF’s reagent:
a reagent consisting of fuchsin bleached by sulfurous acid that produces a red color upon reaction with an aldehyde; it is used for chromosome staining micr
schizocarp:
a dry, two-seeded fruit of some plants that separates at maturity along a midline into two mericarpes; each mericarp has a dry, indehiscent pericarp enclosing a loose-fitting ovule (e.g., carrot) bot
scion: a portion of a shoot or a bud on one plant that is grafted onto a stock of another hort
scion rooting: covering a low graft with soil so that the plant develops roots directly from both the rootstock and the scion meth hort
scission >>> fission
sclerenchyma: tissue composed of cells with thickened and hardened walls bot
sclerophyllous: having leaves stiffened by sclerenchyma bot
sclerotium (sclerotia pl): a dense, compact mycelial mass capable of remaining dormant for extended periods bot
scorch: “burning” of leaf margins as a result of infection or unfavorable environmental conditions phyt
scorpiod cyme:
a determinated inflorescence in which the lateral buds on one side are suppressed during growth, resulting in a curved or coiled arrangement bot
screening:
examining the properties, performance responses of individuals, lines, genotype, or other taxa under an assortment of conditions in order to evaluate the individuals or groups; a routine testing for particular properties meth
screening overkill: when screening a large population for horizontal resistance, there is a danger, in the early breeding cycles, that every
individual will be killed and the entire breeding population lost; it can be prevented by using natural crop protection late in the season, to ensure that the least susceptible plants produce at least a few
seeds phyt
scutellum: a shield-shaped organ of the embryo of grasses; it is often viewed as a highly modified cotyledon in monocots bot
scutiform: platter-shaped bot
SDS >>> sodium dodecyl sulfate-polyacrylamide
SDS gel electrophoresis (sodium dodecyl sulfate-polyacrylamide) (SDS-PAGE): in SDS-PAGE, SDS masks protein charge and separations depending only
on size as compared to common gel electrophoresis meth >>> gel electrophoresis
SDR >>> second division restitution
SE >>> standard error
secalotricum: a cross combination of rye (Secale) and wheat (Triticum) in which rye serves as the donor of the cytoplasm (mother plant), as opposed to triticale bot agr >>> triticale
secondary constriction >>> SAT-zone
secondary crop: a crop that originated as a weed of a primary crop (e.g., rye) evol; in agronomy, a crop grown after a primary crop agr
secondary gene pool:
species in the secondary gene pool include those from which genes can be transferred to the cultivated species, however with more difficulties as compared to species of a primary gene pool evol
secondary infection: any infection caused by inoculum produced as a result of a primary or a subsequent infection and/or an infection caused by
secondary inoculum phyt
secondary pairing:
the association of bivalents in polyploids due to genetic, evolutionary, or structural factors; by any reason those bivalents appear in groups; sometimes it seems that the bivalents of a certain genome are closer together than at random or the bivalents of a certain genome occupy certain domains (spatial order) within the meiotic cell (prometaphase and metaphase) cyto
secondary root >>> lateral root
secondary tiller:
it can arise from the prophyll node and leaf node of the primary tillers in cereals; in the same manner, tertiary tillers may occasionally be produced by secondary tillers; the primary tillers are usually the smallest of the tillers that emerge bot
second division: second meiotic division, which is a mitotic division of chromosomes cyto
second division restitution (SDR):
it is due to premature cytokinesis before the second meiotic division takes place; sister chromatids end up in the same nucleus cyto
section cutting: sections are cut from a block of wax around a plant material, usually by microtome cyto prep
sectorial chimera: a chimera in which the distinct meristem is cross-sectional present, like sectors of a circle bot >>> chemera
>>> Figure 72
sedimentation test: a test for evaluating wheat protein quality flour is suspended in an aqueous solution of lactic acid and held for a time under
specified conditions, then the volume occupied by sediment is measured meth >>> ZELENY test
seed: a mature ovule consisting of an embryonic plant together with a store of food, all surrounded by a protective coat bot >>> Table 13
seed bank: a place or storage in which seeds of rare plants or obsolete varieties are kept, usually vacuum-packed and under cold conditions in
order to prolong their viability meth fore agr hort >>> gene bank
seedbed: a plot of ground prepared for seeds or seedlings agr
seedborne: carried on or in seeds phyt
seedborne pathogens: carried on or in seeds; for example, in wheat, the streak mosaic virus of barley, the fungi, such as snow mold (Fusarium nivale), Septoria spike blotch (Septoria nodorum), Helminthosporum leaf blotch or spot blotch (Cochiobolus sativus, Helminthosporum sativum, syn Bipolaris sorokiana, Drechslera sorokiana), loose smut (Ustilago nuda or U. tritici),
common smut or stinking smut (Tiletia caries), dwarf smut (Tiletia controversa); in barley, the stripe mosaic virus, the fungi, such as snow mold (Fusarium nivale), leaf stripe disease (Pyrenophora graminea), Helminthosporum leaf blotch (Helminthosporum
gramineum, syn Drechslera graminea), net blotch disease (Pyrenophora teres, syn Helminthosporum teres, syn Drechslera teres), loose smut (Ustilago nuda), black smut (Ustilago nigra), hard smut (Ustilago hordei); in rye, the streak mosaic virus of barley, the fungi, such as snow mold (Fusarium nivale, syn Griphosphaeria nivalis), Septoria spike blotch (Septoria nodorum), stalk bunt (Urocystis
occulata syn Tuburcinia occulata), ergot (Claviceps purpurea); in oats, the streak mosaic virus of barley, the fungi, such as loose smut (Ustilago avenea); and in maize, the fungi, such as common smut (Ustilago maydis), seed rots (Fusarium spp., Penicillium spp.), seedling rots (Pythium spp., Fusarium spp., Helminthosporum spp., Penicillium spp., Rhizopus spp., Rhizoctonia spp., Deploida spp.) phyt
seed breeder’s rights:
national and international rules and laws that provide plant breeders a legal means to apply for proprietary rights to cultivated plant varieties they have bred; “breeder”means the person who bred or discovered and developed a variety; “variety” means a plant grouping within a single botanical taxon of the lowest known rank, whose grouping, irrespective of whether the conditions for the grant of a breeder’s right are fully met, can be defined by the expression of the characteristics resulting from a given genotype or combination of genotypes, distinguished from any other plant grouping by the expression of at least one of the said characteristics and considered as a unit with regard to its suitability for being propagated unchanged agr
seed certification: a procedure developed as a means of assuring that the seeds have a high standard of purity and quality seed meth
seed cleaning:
it is done to eliminate weed seeds and various insects; grain that is intended for milling, or marketing as food, must be cleaned of all foreign matter, such as chaff, soil, stones, etc. meth phyt
seed coat: the protective covering of a seed usually composed of the inner and outer integuments bot
seed conditioning: for marketing, seeds are usually cleaned, sized, treated with fungicides, insecticides, or inoculant, and finally bagged seed >>> Table 11
seed counting:
important when determining the >>> hundred seed (grain) weight or the >>> thousand seed (grain) weight to ensure that high yields of grain crops are due to many large seeds, rather than to very many small seeds; the manufacturers of seed testing equipment have various designs of equipment for counting and weighing seeds seed
seed divider: a device that divides a seed lot and puts subsamples directly into a various number of planting envelopes seed >>>
Table 11
seed dormancy >>> dormancy
seed drill >>> drill
seed flat >>> flat
seed grower (pedigreed): an individual or institution who applies for the inspection of a crop offered for pedigree, grows the crop in
accordance with the official regulations and who accepts full responsibility for the production and management of the seed crop and all related financial obligations agr seed
seed health test: specific tests to determine the absence or presence of certain microorganisms known to cause economic loss to crop yield are
carried out in numerous forms; seeds are generally surface sterilized and placed onto agar plates or other substrates, which are known to promote the growth of the disease; the percentage of seeds exhibiting the
disease are used as measure of seed health seed
seed incompatibility: a postgamous sterility due to failure of tissue development involved in the formation of the seed seed
seed increase >>> increase
seed index: the 100-g-weight of seeds seed >>> thousand-grain weight
seeding lath:
commonly a wooden device for obtaining uniformly spaced drills in a seedbed and aiding the even distribution of hand-sown seed in them meth
seeding machine >>> drill
seedling: a young plant grown from seed bot
seedling guard: a row cover to protect seeds indoors or out meth hort
seed leaf >>> cotyledon
seed lot: usually a batch of seed that has all come from one farm or one crop; the whole of one seed lot can be covered by one seed certificate,
and it can be expected to behave uniformly seed
seed mixture: either seed of more than one kind of cultivar or a combination of seed of two or more species seed
seed multiplication: all methods required to grow plants to maturity and produce seeds, including those practices necessary for harvesting,
processing, and preparing seeds for subsequent plantings seed
seed orchard: plantation of fruit or forest trees, assumed or proven genetically to be superior; it is isolated in order to reduce pollination
from genetically inferior outside sources; it is managed to improve the plants and produce frequent, abundant, and easily harvestable seeds hort fore
seed parent:
the strain from which seed is harvested in the hybrid seed field; also commonly used to designate the female parent in any cross-fertilization meth
seed plant: an individual plant that is or was used for seed production and/or maintaining the genotype seed
seed plants >>> sperma(to)phyta
seed potato: a potato tuber that is used for the next growing season in order to produce next generation for selection and experimental testing seed
seed processing: the operations involved in preparing harvested seed for multiplication or marketing seed >>> Table 11
seed production area: in forestry and horticulture, a stand or plantation designated for collection of seeds for reforestation
purposes; it may be rogued of inferior trees and treated in such a manner as to produce large quantities of seed; the wood harvest is usually also an important consideration and the establishment and management
is similar to commercial stands, usually seed production was not an initial consideration at establishment meth fore
seed protein(s) (in wheat) - Samenprotein(e) n: consist of glutenin and gliadin, which belongs to prolamin superfamily; the prolamin
superfamily also includes rice >>> prolamins, rye >>> secalins, maize zeins and barley >>> hordeins; among these prolamin proteins, only wheat prolamins can form a gluten macropolymer;
based on a DNA sequence comparison, it was shown that glutenin, gliadin, hordein and secalin but rice prolamins contained glutamine-rich tandem repetitive sequences; this structure might be involved in protein
elasticity; the number of cysteine residues in these proteins involved in inter- and intra- disulfide bonds varies even within a same species; fractionation of seed proteins by aqueous alcohol with DTT
(insoluble polymeric proteins) or without DTT (soluble polymeric and monomeric proteins) shows that barley hordeins does not form insoluble polymers, probably due to a very low amount of D-hordein, which shared
a similar structure to wheat high-molecular-weight glutenin subunits (HMW-GSs); since HMW-GSs is known to be important to form a structural framework of gluten polymers, the amount of D-hordein might be critical
for hordein polymerization phys
seed quality control: control of physiological, sanitary, and genetic seed quality characteristics seed
seed regulation: the total set of rules and protocols related to variety development and release, seed production, quality control, and delivery seed
seed set: the process of producing seeds after flowering bot agr
seed source: the location where a seed lot was collected; usually defined on an eco-geographic basis by distance, elevation, precipitation,
latitude, etc. fore >>> provenance
seed spacing >>> population density
seed stack:
the erect stem on a plant that produces flowers and seed; it is particularly applied to root crops and leafy vegetable crops that produce seed after the desired product (root, head, leaves) has fully developed agr
seed stand: any stand used as a source of seed fore hort
seed stock: seed used as a source of germplasm for maintaining and increasing seed of crop varieties seed >>> stock seeds
seed testing:
seed offered for sale is usually tested in a seed testing laboratory; the main test is for germination percentage, but other tests can include seed health, freedom from weed seeds, identity and purity of cultivar, etc. seed
seed trap: a device for catching the seeds falling on a small area of ground, from trees or shrubs; it is set for determining the amount of
seedfall and the time, period, rate, and distance of dissemination fore hort
seed-tree method: a method of regenerating a forest stand in which all trees are removed from the area except for a small number of seed-bearing
trees that are left singly or in small groups fore
seed vessel: the pericarp (wall of the ripened ovary), which contains the seeds bot
seed viability testing:
all methods to determine the potential for rapid uniform emergence and development of normal seedlings under both favorable and stress conditions meth seed
http://www.plantstress.com
seed vigor: seed properties that determine the potential for rapid uniform emergence and development of normal seedlings under both favorable and
stress conditions seed
http://www.plantstress.com
segmental allopolyploids: a partial homology or so-called homoeology of chromosome sets combined in an allopolyploid cyto
segregate >>> segregation
segregation: the separation of alleles during meiosis so that each gamete contains only one member of each pair of alleles gene >>> Figure 6 >>> Tables 2, 3, 4, 6, 7, 8, 19, 20, 21
segregation distortion:
the distortion of the 1:1 segregation ratio produced by a heterozygote; it can arise because of abnormalities of meiosis, which results in an Aa individual producing an unequal number of A and a bearing gametes or it may arise from A and a bearing gametes being unequally effective in producing zygotes gene
select (synthetic):
a category for a specific combination of seed lots from inspected breeder or foundation of crop used in the production of a certified seed crop seed meth
selectable marker:
a physiological or morphological character, which may easily be determined as marker for its own selection or for selection of other traits closely linked to that marker gene
selection:
the process determining the relative share allotted individuals of different genotypes in the propagation of a population; natural selection occurs if zygotic genotypes differ with regard to fitness meth evol >>> clonal
selection >>> differential selection >>> index selection >>> mass selection >>> recurrent selection >>> tandem selection >>> Figures 38, 39 >>> Table 7
selection after flowering:
a selection that is only possible after flowering since the critical selective characters are expressed after flowering time, seed and/or fruit formation period (e.g., grain size, spike length, fruit color, etc.) meth
selection coefficient: a measure of the disadvantage of a given genotype in a population stat >>> Figure 38
selection criteria: the specific characters and plant reactions on which the selection is focused during the breeding cycles meth
selection differential:
in artificial selection, the difference in mean phenotypic value between the individuals selected as parents of the following generation and the whole population meth stat >>> Figure 38
selection gain:
in artificial selection, the difference in mean phenotypic value between the progeny of the selected parents and the parental generation gene meth >>> Figure 38
selection intensity: the ratio of the number of genotypes selected divided by the number of genotypes tested meth gene stat >>>
Figure 38
selection limit: the exhaustion of genetic variance in a population, so that no further selection response can be expected gene
selection pressure: the effectiveness of natural selection in altering the genetic composition of a population over a series of generations stat meth >>> Figure 38
selection prior to flowering: a selection that is possible before flowering since the critical selective characters are already expressed (e.g.,
seedling resistance, tillering capacity, head size in cabbage, etc.) meth
selection response: the difference between the mean of the individuals selected to be parents and the mean of their offspring; it is expressed by
the formula R = h2 × S (h2 = heritability, S = selection coefficient = phenotypic difference between the mean of all selected fractions and the mean of total population) gene stat >>> Figure 38
selective advantage:
an advantage for survival of a genotype in a population and for production of viable progeny as compared to other genotypes, which may show a selective disadvantage with respect to fitness and viability meth stat >>> Figure 38
selective agent:
an environmental or chemical agent that imposes a lethal or sublethal stress on growing plants, or portions thereof in culture, enabling selection of resistant or tolerant individuals biot
http://www.plantstress.com
selective breeding: selecting and mating species with characteristics that were chosen from past performance meth
selective culture medium >>> selective agent
selective disadvantage: inferior fitness of one genotype compared to others in the population meth stat >>> selective advantage
selective fertilization: the nonrandom participation of male or female gametes or different genotypes in the formation of zygotes and/or hybrids bot
selective gametocide: a treatment that inactivates certain gametes, such as one that produces male sterility but does not affect the female
gametes meth seed
selective herbicide:
a herbicide that acts against either monocots or dicots, against weeds and not against crop plants or even against species weeds phyt
selective medium >>> selective agent
select plot grower: a seed grower who has been approved by an official organization for the production of select seed crops; this person or
institution has completed a for example three-year probationary period of plot production after three recent years of pedigreed seed crop production seed agr
select seed: the approved progeny of breeder or select seed produced in a manner by seed growers authorized by an official organization to
maintain its varietal identity and purity; select seed may be produced from select seed for a maximum of five multiplications from breeder seed seed meth
.... and much more
sequence-tagged-microsatellite(s) (STMs) marker: >>>primers constructed from the flanking regions of >>> microsatellite
DNA which can be used in >>> PCR reactions to amplify the repeat region biot meth >>> sequence-tagged-site
sequential cropping: a multiple cropping pattern characterized by two or more crops growingin sequence on the same field within a year; the
succeeding crop is planted after the preceding one hasbeen harvested; there is no intercrop competition agr
set(t):
a short piece of a stem or a plantlet used for propagation, e.g., in >>> sugarcane it is used for >>> vegetative propagation; each set(t) usually has three nodes and the cut ends are often dipped in a mixture of insecticide and fungicide; the first >>> crop from these set(t)s is called the “plant crop” while all subsequent crops are called >>> ratoon crops, until replanting becomes necessary hort agr
shifting cultivation:
a type of farming in which fields are used for a few years, and are then left to grow in a wild state for many years; this allows the soil to recover and become rich and fertile again as well as allows to escape from >>> parasites; the method is used in areas of low population density; the system is also known as “slash and burn” agr eco
shuttle breeding:
a program that shuttles seed between two (or more) locations to be grown at each; this method was introduced by Dr. N. BORLAUG and is a proven contributor to success of CIMMYT (Mexico); shuttle breeding allows two breeding cycles per year instead of one, e.g., a winter cycle in the northern desert of Sonora and a summer crop in the central Mexican highlands; this not only fast-forwards selection, but also exposes test varieties to radically different day lengths, temperatures, altitudes, and diseases; resulting plants are broadly adapted; they grow well in numerous environments meth
silica gel: thesubstance absorbs water vapor and it is put into air-tight containers to keep the contents dry; it is particularly valuable for the
long-term storage of seeds in genetic conservation seed meth
.... and much more
silvics: the study of the life history and general characteristics of forest trees and stands with particular reference to locality factors, as a
basis for the practice of silviculture fore >>> silviculture
.... and much more
sinapate ester:
in rapeseed meal a high content of phenolic acid esters is common, mainly sinapate esters, which have been shown to cause a dark color and a bitter taste of meal and derived protein products; therefore, increasing the meal and protein quality of winter rapeseed (Brassica napus) is of importance in rapeseed breeding for food and feed purposes chem
single-cross hybrid: the first generation of a cross between two specified inbred lines seed meth
single-gene character:
any genetic trait whose inheritance is controlled by a single gene; the inheritance of a single-gene character follows MENDEL’s laws of inheritance gene
single-nucleotide polymorphisms (SNPs): it refers to variations (in individual nucleotides) that occur within DNA at the rate of
approximately one in every 1,300 bp in most organisms; SNPs usually occur in the same genomic location in different individuals biot
single-polymorphic amplified test (SPLAT): if sequence-tagged-site (STS) do not reveal polymorphism, it is usually converted into SPLAT;
individual STS products from different genotypes are themselves sequenced; any difference revealed can be sequences from nuclear ribosomal DNA; they can be exploited in the production of internal primers; in
general single-polymorphic amplified sequences are dominant markers biot
single-seed descent (SSD):
derivation of plants by a selection procedure in which F2 plants and their progeny are advanced by single seeds until genetic purity is achieved; single-seed descent methods (single-seed, single-hill, multiple-seed) are easy ways to maintain populations during inbreeding; natural selection cannot influence the population, unless genotypes differ in their ability to produce viable seeds; artificial selection is based on the phenotype of individual plants, not on the progeny performance meth >>> Figure 16
single sequence repeat (SSR) DNA marker technique: a genetic mapping technique that utilizes the fact that microsatellite sequences repeat
(appear repeatedly in sequence within the DNA molecule) in a manner enabling them to be used as markers biot
http://wheat.pw.usda.gov/ITMI/Repeats/index.shtml
single-strand conformational polymorphism (SSCP): this feature relies on secondary and tertiary structural differences between denatured
and rapidly cooled amplified DNA fragments that differ slightly in their DNA sequences; different SSCP alleles are resolved on non-denaturing acrylamide gels, usually at low temperatures; the ability to resolve
alleles depends on the conditions of electrophoresis and this requires DNA sequence data biot
sink: a term used for storage organs of a plant into which products of photosynthesis are translocated and stored (grain, fruit, tubers, roots as
in carrot, stem as in sugarcane) phys
SMITH model (for quantitative genetic analysis): selection and random genetic drift are the main forces affecting selection response in
recurrent selection programs; the correct assessment of both forces allows a better comparison of the efficiency of different recurrent selection schemes; the population diallel analysis proposed by HAMMOND
& GARDNER (1974) and the model proposed by SMITH (1979) with full consideration of inbreeding depression due to random genetic drift can also be applied to quantitative analysis; the effect of random genetic
drift is expected to be large, particularly in studies with many selection cycles and/or high rates of inbreeding; therefore, the extension of the population diallel allows a better assessment of the selection
response in recurrent selection stat meth
SMOOTH: a statistical method to remove genotyping errors from genetic linkage data during the mapping process; the program SMOOTH
calculates the difference between the observed and predicted values of data points based on data points of neighbouring loci in a given marker order; highly improbable data points are removed by the program in
an iterative process with a mapping algorithm that recalculates the map after cleaning; the method is able to detect a high amount of scoring errors and demonstrates that the program enables mapping software to
successfully construct a very accurate high-density map stat meth
soap insecticide:
a solution of soft soap, i.e., potassium soap, has been traditionally used to control aphids and similar insect pests; also water with a small content of dish detergent can be used; the affected insects are unable to breathe, and these insecticides are stable phyt
softwood:
one of the botanical groups of trees that in most cases have needle or scale-like leaves; the conifers; also, the wood produced by such trees bot fore
source identified: the seed certification class of pre-variety germplasm which provides third party assurance of geographic origin, usually for
perennial native forage grasses, legumes and forbs produced from parent populations which have not been selected; source identified class seed labels identify the original geographic location, of the collection
or production, that has been declared by the responsible plant breeder seed meth
SPLAT >>> single-polymorphic amplified test
.... and much more
spicula: a small or secondary spike bot >>> Picture 013
spicule(s): minute teeth occurring on the nerves and other parts of the lemma and glume of, for example, wheat, barley, oats, grasses, etc. bot >>> Picture 013
spike: a “flower” head on which the spikelets are borne without a stalk as, for example, in wheat, barley, rye or other grasses bot >>> Figure 34 >>> Picture 013
spike-bed method: a spike-bed is a seedbed in which the seeds from one spike are sown in same sequence in which they were arranged in the spike; thus the plants in the
>>> seedbed reflect the quality of the original spike; the method is applicable not only for cereals but also for other crops meth >>> selection method
spike density: the number of spikelets per unit of spike length; it is a distinctive character of certain cereal varieties bot agr >>> Figure 34 >>> Picture 013
spikelet: the unit of inflorescence in the cereals and in some grasses consisting of a pair of glumes and one or more florets bot >>> Picture 013
spikelet glume: a chafflike bract; specifically one of the two empty chaffy bracts at the base of the spikelet in the grasses bot >>> Picture 013
spindle: the set of microtubular fibers that appear to move the chromosomes of eukaryotes during mitotic and meiotic cell division cyto
spindle attachment >>> centromere
spindle poison: any poison affecting the correct formation or function of the spindle of the dividing cell cyto
.... and much more
split plot design (synnested block design): it allows the testing of two factors in combination; one factor (the main effect) serves
as a replication for the second factor (the split effect); there are many split plot design options, but the basic principle involves assigning one set of treatments to the main plots that are arranged in
randomized complete blocks; the second set of treatments is assigned to subplots within each main plot; the statistical analysis is similar to that used with the randomized complete block design, i.e., an ANOVA
set up for a split plot is followed by a means comparison test such as the DUNN's test or DUNCAN's multiple range test agr meth stat
spreader row >>> spreader
spreader surround(s): they differ from >>> spreader row(s) in that they surround the screening population rather than run through
it; they are used when parasite gradients are not a problem phyt meth
square design: a design if it has equally many points and blocks stat
square lattice design >>> lattice design
SSCP >>> single-strand conformational polymorphism
SSLP >>> microsatellite marker
staple:
the main item of a diet, hence “staple crop” and ”staple food”; staple crops can be divided in to >>> major and >>> minor staples agr
StarLinkTM: an insect-resistant variety of maize that was not labeled for human consumption agr
starter culture: pure culture or mixture of microorganisms which is used for starting fermentation during commercial production of a biofertilizer biot
starter dose: a small dose of fertilizer given to a crop before planting so as to give it a head start even in fertile soil, e.g., 20-25 kg N/ha
to a grain legume till the N fixation system becomes operational or a small early application in a fertile soil or under adverse growth condition agr
stenospermocarpy - Samenlosigkeit f:
seedlessness in some fruits, e.g. , in some melons, squashes, table grapes, citrus fruits etc.; normal pollination and fertilization is required to set fruit in stenospermocarpic fruits; the near seedless condition results from subsequent abortion of the embryo that began growing following fertilization; the remains of the undeveloped seed are often visible in the fruit bot hort
stock seeds (parent ~): the supply of seeds, tubers, or other propagules reserved for planting, multiplication, or used as a source of
germplasm for maintaining and increasing seed of crop varieties or genetic tester lines seed meth
stone fruit: fruits of the botanical family Rosaceae that contain a single hard seed, called a stone, pit, or pip; the term includes >>> plums, >>> cherries, greengages, peaches, apricots, almonds, and sloes bot hort >>> drupe
sugarbeet root maggot (SBRM):
a major insect pest of sugar beet throughout much of North America; recently, two insecticides with the same mode of action are used almost exclusively for SBRM control; alternative control strategies would be required if insecticide-resistant SBRM developed or the insecticides were no longer available due to regulatory actions; germplasm lines with SBRM resistance are available, but information on the SBRM resistance of hybrid cultivars created by crossing these lines with a SBRM-susceptible cms parental line is still lacking, Tetanops myopaeformis phyt
sweep: tree defect resulting from a gradual curve in the main stem of the tree hort fore
synteny: chromosomal association of genes (linkage) established in somatic-cell culture phys gene; in biotechnology, the conservation of the gene order on the chromosomes; it allows understanding of the evolutionary relationships between species; until the 1980s it was imagined that each crop plant had its own genetic map; by using the first >>> RFLP markers it turned out that related species had remarkably similar gene maps; it demonstrated conservation over a few million years of evolution in syntenous relationships between potato and tomato in the broad-leafed plants and between the three genomes of bread wheat in the grasses; later it was shown that the same similarities held over the rice, wheat and maize genomes, which were separated by some 60 million years of evolution; the discovery of synteny has had an enormous impact on the way we think about plant genetics; there are great opportunities to predict the presence and location of a gene in one species from what it is known from another; for practical plant breeding, knowledge of synteny allows breeders access to all alleles in, for example, all cereals rather than just the species on which they are working; a key first example of this is the transfer to rice of the wheat dwarfing genes that made the >>> Green Revolution possible; in these experiments the gene was located in rice by synteny and then isolated and engineered with the alteration in DNA sequence that characterized the wheat genes before replacing the engineered gene in rice; this approach can be applied to any gene in any cereal, including the so-called >>> orphan crops that have not attracted the research interest that wheat, rice, or maize have over the past century biot evol
http://www.desicca.de/Rye gene map
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