Statistical Methods in Seed Corn Product Selection

Abstract

Our purpose is to examine statistical methods, particularly field plot technique, hypothesis testing, and inference suggesting, from a seed corn (Zea mays L.) company viewpoint. Company managers must look beyond traditional statistical methods to develop systems that identify superior new products. These systems should mimic the processes used by farmers in selecting new hybrids that provide superior performance in the broad range of environments where they will be grown. This paper shows the evolution of seed company strategy to identify superior hybrids in product development and testing systems. Test resource allocation has changed to fewer replicates per location, to more locations per year, to more years per hybrid comparison, and to more data integration across test types. Experimental design has changed from sophisticated to simple designs, from experiment summaries to head‐to‐head comparisons (two hybrids compared in all tests in which both were grown) then to head‐to‐group comparisons (series of head‐to‐head comparisons for a hybrid with appropriate elite hybrids within a maturity group), and from analyses of variance to t‐test analyses. Stability regressions have become more popular. As improved statistical methods have been used, more genetic progress per unit of time has resulted; hybrids have become more stress tolerant, thus more widely adapted.

Using Interaction in Two-Way Data Tables

“…Twice as many genotypes, or twice as many environments, explored with nearly th~ same cost implies much flexible, efficient, informative expenments. Such advantages particularly significant given current, well-motivated trends toward replications and more test environments (Bradley et al 1988). more are fewer Furthermore, the option to impute missing cells accurately opens even ~reater possibilities for clever, efficient experiments.…”

Genetic gains in grain yield, morphological traits and yield stability of middle-late maize hybrids released in Serbia between 1978 and 2011

“…Hybrid yield stability increase in later breeding periods can be best explained on an example from the USA during the 1980s, when a turning point in the evaluation of hybrids occurred. Namely, the number of localities for hybrid combinations testing continued to grow which allowed the identification of maize hybrids that are characterized by ample adaptability, and therefore greater yield stability (Bradley et al 1988). A similar approach was adopted in Serbia during the early 2000s, after which the testing network of experimental hybrids was significantly expanded.…”

Advances in crop phenotyping and multi-environment trials

“…An analysis of the literature [72][73][74][75][76][77][78][79] , summarized here, identifies the main characteristics of MET in the USA at each stage of its development (Table 1).…”