1. A method for selective plant breeding for a continuous target phenotypic feature in plants, the method comprising: determining by direct DNA sequencing the genotype of the plants of a plant population for at least one molecular genetic marker selected from the group consisting of a DNA molecular marker and an RNA molecular marker; providing an original data set comprising a set of variables, wherein at least one of the variables in the original data set comprises a value representing the genotype of each of the plants for the molecular genetic marker(s); determining at least one association rule associating the continuous target phenotypic feature with the variables from the original data set utilizing a computer and one or more association rule mining algorithms; utilizing the association rule(s) to create one or more new variables; adding the new variable(s) to the original data set to produce a larger data set that contains more variables than the original data set; developing a plurality of models for prediction or classification of the continuous target phenotypic feature using all the variables of the larger data set; utilizing cross-validation to compare the predictive value of each of the plurality of models, and selecting the model that gives the most accurate prediction of the presence or classification of the continuous target phenotypic feature; utilizing the selected model and the larger data set to predict the presence of or classification of the continuous target phenotypic feature in plants comprising specific values for each of the variables in the larger data set; utilizing the predicted presence or classification of the continuous target phenotypic feature in plants comprising specific values for each of the variables in the larger data set to select a first parental plant and a second parental plant from the plants of the plant population; and breeding the first and second parental plants, thereby forming a progeny plant population comprising the continuous target phenotypic feature.