. . . . .  Soybean Aphids May Have Caused Up to 13 Bushels Per Acre Yield Loss in Some Fields South of I-90 in 2004 . . . . Results of  2004 Research at USDA-ARS-NGIRL Confirmed Our Threshold Recommendations . . . . . Yield Loss Recorded Even at Initial 1 Aphid Per Plant at V5 and R2 . . . . . Hee-Yo, We Are Correct Sir . . . . . Ollie Two-Fifty Desperate . . . . . Tried To Convince Buford . . . . .

No Soybean Aphids, Eh Buford?   

Now that I have already presented our 2004 data in two meetings, I suppose I can slowly
post them on the Internet.  I still want you to attend our county meetings so I will not be posting
all the good stuff until our last meetings in March 2005.

We are still counting soybean aphids that we put in the freezer last August, so the aphid counts
are still incomplete.  So far, we have counted as high as 3,148 aphids per plant on August 19
in the untreated plots.

In terms of yield, not all insecticides are created equal.  We observed this in 2002.  We
confirmed it in 2004.  And I do not know the exact reason behind this observation.

Lastly,  time may be of the essence when deciding to spray or not.  Delaying the spray from
R2 to R3 may cost you over 1 bushel per acre.

Ten Glorious Years of Gilded Genes?    

Just before the Christmas break, a distinguished editor of a farm journal asked me
what I would recommend in terms of growing Bt corn in 2005.  In researching for my
response to him, I noticed that 2005 will in fact be the tenth year that we will be growing
Bt corn here in South Dakota.  And I have been keeping score on how Bt corn hybrids
perform here since 1996 both in counties to the north with the univoltine (one-peaked)
moth flight, as well as in the south with the bivoltine (two-peaked) moth flight.

Since it is the tenth year anniversary of Bt corn in South Dakota, and my data are just
gathering dust in my USB memory stick, I thought posting them on the Internet may
be a good idea and perhaps generate some discussion among Bt corn enthusiasts.

The word "Bt corn" has of course changed with the introduction of newer genes that
will work on insects besides corn borers.  Included in my tables above are only the Bt
corn that are meant to control European corn borer larvae.  Corn hybrids containing
Herculex I, YieldGard Rootworm, and YieldGard Plus are not included yet.

So, has it really been ten glorious years of Bt corn in SD? What is your experience
with growing Bt corn?  Does it make you money every single year?  Should you consider
Bt corn as insurance or investment?  Are you able to recoup the technology fee every
single time you grow Bt corn?


For more information:  http://plantsci.sdstate.edu/ent/ecb/ecb_mgmt_SD.htm

                                            Happy New Year!


© Copyright 2009 by South Dakota State University.  All Rights Reserved.
 

 Web Posted on Thursday, December 16, 2004 by Mike Catangui. Last updated on Friday January 7, 2005.