Skip the navigation header

K-State Logo K-State Research and Extension logo
go to Research and Extension home page go to News go to Publications and Videos ask a question or make a comment search the Research and Extension site

body

Sunflower Scene Logo  
May June July
August September October

August 19

August 5

August 8

August 11

August 15

August 19

August 20

August 26

 

 

General view Aug19,2003Well, the heat and lack of rain have finally caught up with our field.  Even though it's only about 11:00 AM the plants don't have that nice crisp, turgid appearance.  This drought, combined with the heat will likely cause some yield losses.  Kernels will not develop normally and they will be lighter. 

Dry leavesThese are classic symptoms of drought damage. The lower leaves are yellowing and drying up.  Note the cracks in the soil.  It has been miserably hot and dry. 


Head frontThis head doesn't appear to have any drought symptoms.  I dusted off the dried-up floral parts in a small area to expose some seeds.


Back of headThe back of the head including the bracts is almost completely yellow now.  This plant is in late R8 or early R9 stage of maturity.  When the bracts are brown it will be in the R9 stage, which is physiological maturity.  I don't see any Rhizopus head rot damage.


Cross sectionThis is a cross section of the head we were just looking at.  You can see the brown areas across the head where head moth larvae have been burrowing.  It appears to be a little more severe on the left side.


Close up cross sectionThis is a closeup of the left side. There's considerable burrowing and damage. I'm surprised there's not more
Rhizopus head rot in some of these heads, especially considering all the head moth damage.  I'm wondering now if we made the right decision when we choose not to spray for the sunflower head moth. 


Head moth larvaeIt's pretty easy to find the head moth larva.  This one didn't want his/her picture taken and is trying to escape.  Notice the longitudinal (lengthwise) brown and light stripes and brown head capsule.