Variety is the Spice of Life for Corn, Too

Scientific matchmaking in cornfields on more than 40 Minnesota farms indicates farmers should consider moving away from the traditional approach of growing only one or two hybrids in large blocks, with little cross pollination between them.

Research tests last year found small but significant yield increases from allowing different hybrid pairs to cross-pollinate.

The tests, continuing this year, were run by Agricultural Research Service scientists in collaboration with farmers, seed companies and a crop consulting firm. When hybrids from different companies were paired, they yielded an average four bushels more corn per acre. The highest-yielding pairs produced kernels up to 3 percent larger with up to 0.4 percent more protein.

The yield advantage of pairing hybrids from different companies implies that each hybrid in the pair had different parents. Inbreeding--pollination between plants of the same or very similar genetics--is known to weaken crop vigor.

To implement the new approach, farmers need only plant two unrelated hybrids in alternating rows or mix them in the seed hopper.

Click here for a November 1997 Agricultural Research magazine feature that gives more background about the corn-hybrid studies, as well as other research at the Morris, Minn., lab.

ARS plant physiologist Mark E. Westgate at Morris, Minn., is leading the tests. He's collaborating with several seed companies and CENTROL Crop Consultants, Inc., of Morris. The ARS scientists are growing about 80 corn hybrids this year to determine which pairs synchronize their pollen-shedding and silk emergence--and thus could be fruitful matches.

If the results hold, CENTROL will recommend paired hybrids to its network of consultants and farmers in time for the 1999 season. Eventually, breeders might add a new criterion for selecting a hybrid: How well does it cross-pollinate with other hybrids?

Scientific contact: Mark E. Westgate, ARS North Central Soil Conservation Research Laboratory, Morris, Minn., phone (320) 589-3411, Ext. 132, Fax (320) 589-3787, mwestgate@mail.mrsars.usda.gov.