The CT trait appears to confer drought resistance. Under extreme levels of stress (the lowest-yielding 6 locations), the CT trait increased grain yield by 19 bushels per acre,provided that a second trait, ESY, was also present. (Click here to see data.) Additional research is needed to determine the effect of both CT and ESY, particularly in different genetic backgrounds and hybrid combinations.
Development of Cold Tolerant (CT) Trait
FCR is uniquely situated for the development of cold tolerant native traits. The research farm is approximately 30 miles east of Lake Michigan, just west of Kalamazoo in an area locals refer to as the “snow belt.” In other words, Oshtemo Township is in close enough proximity to Lake Michigan to experience lake effect snows. The same weather feature is also prevalent during the spring planting season. The practical benefit from a selection standpoint is a long period of moderately cool weather commencing in late April and continuing through May. The average date of the last frost is mid-May. Early-planted corn not only experiences cold soil conditions, but in most years must be able to re-emerge after a frost has killed the above-ground vegetation. We believe that having a sustained period of cold stress each year aided our effort to develop the CT trait.
A second contributing factor was a fortuitous choice of germplasm. The particular native strain used to develop CT was a late-maturing landrace that would not otherwise have been an obvious material to screen for cold tolerance. However, this open-pollinated variety had originally been grown in higher mountain elevations and is apparently a good source of cold tolerance. Transferring the trait to an elite genetic background is now the main challenge.
Development of ESY Trait
Enhanced Seed Yield (ESY) was the first trait developed using the SPS breeding methodology. (Click here for more information on SPS.) A composite of genetically-diverse strains was obtained from the GEM (Germplasm Enhancement of Maize) project. It was found that ESY improved per se yield under drought stress and under normal growing conditions as well. (Click here to see data.) Other research demonstrated that selection for per se performance could increase hybrid production as well. That is, the hybrid performance of B73ESY is essentially equal to the hybrid performance of LH132, an inbred that is supposedly more elite. (Click here for hybrid data.)
Future Development Activities
Please contact us if you would like additional information on either past or future development efforts.