The term phenotype is derived from the Greek words phainen (“to show”) and typos (“type”). A phenotype is essentially the composite of an organism’s observable characteristics and traits, including the morphology, development, biochemical and physiological properties, behavior, phenology, and various products of behavior of the organism. Phenotypes come from the expression of an organism’s genes, as well as the influence that the environment extends on the organism and the interactions between environment and organism.
The genotype of the organism contains the inherited “instructions” that will dictate its genetic code. However, not all organisms with the same genotype will look or act the same way, as the environmental and developmental conditions that the organism has been subjected to. Also, it is important to note that not all organisms that look alike have the same genotype.
In 1911, the Danish geneticist Wilhelm Johannsen proposed a distinction between genotypes and phenotypes in order to make clear the difference between the heredity of the organism and what this heredity produces. Johannsen’s genotype-phenotype distinction is very similar to that proposed by an evolutionary biologist, August Weismann. In his distinction proposal, Weismann stated the differences between the germ plasm (which is involved with heredity) and the somatic cells (referring to the body).
While it might seem that anything that depends on the genotype is a phenotype (including molecules such as proteins and the RNA). This is because most molecules and structures that are coded by the genetic material are not visible in the appearance of the organism, but they are observable and can be considered as part of the phenotype. Human blood groups are an example of an invisible yet observable phenotype.
This category contains scientific information on phenotype, the composite of an organism’s observable characteristics and traits, including the morphology, development, biochemical and physiological properties, behavior, phenology, and various products of behavior of the organism.
Rocha, Jl; Baker, Jf; Womack, Je; Sanders, Jo; Taylor, Jf, 1992: Statistical associations between restriction fragment length polymorphisms and quantitative traits in beef cattle. Journal of animal science 70(11): 3360-3370 Data on 41 traits from 677 animals produced in a five-breed diallel were matched with genotypes for five marker-loci provided by restriction fragment length polymorphisms [...]
Knapp, Eric E.; Teuber, Larry R., 1994: Selection progress for ease of floret tripping in alfalfa. Crop Science. 34(2): 323-326 Breeding alfalfa (Medicago saliva L.) for florets that are more easily tripped by honey bees (Apis mellifera L.) has been proposed as a means of increasing efficiency of pollination and improving seed yield. The purpose [...]
Kmiec, Marek, 1993: Segregation of transferrin alleles in a flock of long-wool sheep. Genetica Polonica. 34(3): 273-285 Studies on transferrin polymorphism in the flock of long-wool sheep from the State Animal Breeding Station in Bobrowniki were carried out. Genetic structure of the population consisting of 6832 animals (171 rams, 3050 ewes and 3611 lambs) was [...]
Cooper, M; Delacy, Ih, 1994: Relationships among analytical methods used to study genotypic variation and genotype-by-environment interaction in plant breeding multi-environment experiments. Theoretical and applied genetics 88(5): 561-572 Following the recognition of the importance of dealing with the effects of genotype-by-environment (G X E) interaction in multi-environment testing of genotypes in plant breeding programs, there [...]
Ceccarelli, Salvatore; Grando, Stefania; Hamblin, John, 1992: Relationship between barley grain yield measured in low- and high-yielding environments. Euphytica. 64(1-2): 49-58 The paper addresses the general question of identifying the optimum environment for selection in plant breeding programs for low input agricultural systems. After defining low-yielding and high-yielding environments based on the average grain yield [...]
Kelly, Carol A., 1993: Quantitative genetics of size and phenology of life-history traits in Chamaecrista fasciculata. Evolution. 47(1): 88-97 Despite numerous adaptive scenarios concerning the evolution of plant life-history phenologies few studies have examined the heritable basis for and genetic correlations among these phenologies. Documentation of genetic variation for and covariation among reproductive phenologies is [...]
Gonzalez, J. M.; Lopez, L. A.; Bernard, S.; Jouve, N., 1993: Prolamin analysis of progenies from androgenetic plants of triticale. Plant Breeding. 111(1): 42-48 The present work reports results of the analysis of variability of prolamins in five breeding lines of triticale and 61 androgenetic progenies obtained from them by in vitro culture of the [...]
Johansson, Kjell; Kennedy, Brian W.; Quinton, Margaret, 1993: Prediction of breeding values and dominance effects from mixed models with approximations of the dominance relationship matrix. Livestock Production Science. 34(3-4): 213-223 A simulation study was performed to evaluate the performance of mixed model equations for estimation of additive and dominance effects with two different dominance relationship [...]
Villanueva, B.; Wray, N. R.; Thompson, R., 1993: Prediction of asymptotic rates of response from selection on multiple traits using univariate and multivariate best linear unbiased predictors. Animal Production. 57(1): 1-13 Predicted rate of genetic response for multiple trait breeding objectives from multivariate analyses is compared with that from univariate analyses for a range of [...]
Hopkins, Andrew A.; Vogel, Kenneth P.; Moore, Kenneth J., 1993: Predicted and realized gains from selection for in vitro dry matter digestibility and forage yield in switchgrass. Crop Science. 33(2): 253-258 Improved forage yield and quantity, which can lead to more efficient livestock production, are important goals in switchgrass (Panicum virgatum L.) breeding. of this [...]