Corn Journal
  • Corn Journal
  • Author
  • Stalk Rot Booklet
  • Seed Testing
  • Corn Genetics
  • Pathology
  • Sponsors
  • Contact
"You can see a lot by just looking"-Yogi Berra

carbohydrate depletion in stalk

8/27/2020

 
Annual plants such as corn undergo physiological changes after flowering, especially in corn that is genetically selected to maximize capture of products of photosynthates in the grain. Flow of carbohydrates within the plant are directed by hormones produced in meristems.  Before flowering that flow went to growing leaves and roots near meristems.  Excess carbs were stored in parenchyma cells in stalk tissues.  After flowering, hormones direct the flow towards the developing kernels.
 
Genetics and environments influence the intensity of the flow. Hybrids that tend to have more total starch in the ear either because of more kernels or larger kernels are favored by humans but risk early death of roots and leaf tissue that still require the energy provided by carbohydrates for cellular metabolism.  Environments that reduce optimum photosynthesis during the grain fill period accelerate the depletion of carbohydrate reserves stored in the stalk tissue.  In some hybrids, perhaps all, the depletion becomes most evident in the stalk tissue near the flag leaf, eventually resulting in an abscission layer to form at the base of the flag leaf, cutting off water to that leaf and eventual wilting of the leaf.  Fungi such as Colletotrichum graminicolaare able to invade the outer rind of that small stalk tissue with typical anthracnose symptoms.  This loss of productive photosynthetic tissue in the small leaf is insignificant and could be indicating good grain fill. Loss of significant root tissue is more important.
 
The challenge of the corn breeder is to select hybrids that have the balance of maximum grain production capturing all carbohydrates available without causing too much damage to needed life functions in the plant.  The challenge of the grower is to provide environments that maximize this 
​

Comments are closed.

    About Corn Journal

    The purpose of this blog is to share perspectives of the biology of corn, its seed and diseases in a mix of technical and not so technical terms with all who are interested in this major crop. With more technical references to any of the topics easily available on the web with a search of key words, the blog will rarely cite references but will attempt to be accurate. Comments are welcome but will be screened before publishing. Comments and questions directed to the author by emails are encouraged.

    Archives

    December 2021
    November 2021
    October 2021
    September 2021
    August 2021
    July 2021
    June 2021
    May 2021
    April 2021
    March 2021
    February 2021
    January 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    July 2020
    June 2020
    May 2020
    April 2020
    March 2020
    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015

    Categories

    All

    RSS Feed

© COPYRIGHT 2023. ALL RIGHTS RESERVED
  • Corn Journal
  • Author
  • Stalk Rot Booklet
  • Seed Testing
  • Corn Genetics
  • Pathology
  • Sponsors
  • Contact