Imbibitional chilling injury is
an annual issue associated with field corn but we rarely associate this damage
to soybean. Why am I raising this red flag in 2013… many reports of soybean seed containing
low seed water content (dependent upon the area where the seed was grown). Bedi and Basra (1993), defined imbibitional
chilling injury as sensitivity of seed to a combination of low seed water
content and imbibition at cold temperatures. As we all know some of our 2013
soybean seed is of decreased seed quality caused by the drought of 2012.
We couple this fact with the current forecast and our eagerness to plant and I foresee
potential issues on the near horizon. The
challenge for growers and agronomists is the strong genetic predisposition for this phenomenon. Bramlage et al (1979)
screened soybean cultivars for sensitivity to imbibitional chilling injury. All
were susceptible to some injury but that susceptibility varied greatly. Some
showed no injury at 45° F (7 C) whereas others were damaged at 63° F (17 C).
This means as your scouting and trying to deduce stand issues your suspect field may look like a train wreck whereas neighboring fields look great.
Lastly I know the question of
seed treatments will arise. It is unclear to me the role that todays seed treatments
or polymer coatings have in mitigating imbibitional chilling injury. Therefore
unless you are absolutely certain you have high quality seed that is 13%
moisture with a perfect seed coat I would suggest we just wait a week for
warmer weather before we start pounding our seed into this cold wet soil.
WI Soy Podcast with Pam Jahnke: Soybean Seed Quality and Chilling Injury
Literature cited.
Bedi,
S. and A.S. Basra. 1993. Chilling injury in germinating seeds: basic mechanisms
and agricultural implications. Seed Science Research. 3:219-229.
Bramlage,
W.J., A.C. Leopold, and J.E. Specht. 1979. Imbibitional Chilling Sensitivity
Among Soybean Cultivars. Crop Sci. 19:811-814.
