Disclaimer: The author accepts no responsibility for any use of the following tips.
They represent personal opinions only not proven or trialed data.
Nor are they necessarily approved by the chemical manufacturers.
The tips should be verified for relevance to your own situations / soil conditions /local regulations.
Tip of the month,(May/June) Winter wheat and barley crops:
Strobilurins still quite expensive but very cost effective. Consider splitting the dose and mix and matching.
for examlple a very robust flag leaf spray would be 0.4 litres of Landmark (kresoxim-methyl +epoxiconazole)
plus 0.4 litres of Opera (pyraclostrobin +epoxiconazole). This not only makes the spray cheaper than say
0.8 litres of landmark but gives the dual effect of the two different action modes of the strobs.
ie vapour movement of the kresoxim-methyl and robustness/stability of the pyraclostrobin.
Tip of the month,(Sept/Nov) Winter wheat and barley crops:
Isoproturon can be hot on lush new growth with frosts imminent,
especially in mixes with aphicide, more especially on barley.
however if weed growth matches crop growth take advantage of reduced rates to match application rate to weed size.
My Impirical Rule: apply interim dose of one litre of Isoproturon per hectare per leaf of crop, up to five litres per hectare maximum
(or less if local regulations apply)
Reasoning: small weeds are more susceptible especially so at one leaf stage, but crop could be scorced badly at full rate at this stage.
This rule allows spraying to proceed without waiting for the normal two /three leaf stage, trifuralin and aphicide can be added if required, which may benefit from earlier application..
Follow up: Don't forget to follow up later when crop more hardy with the remainder of the dose, as low rates will not control later emerging weeds
An exiting new range of agrochemicals is about to hit the market possible next spring (1997)
These have major advantages over present agrochemicals:
Increased active life on the crop.
Control for up to 8 weeks is being claimed.
Low toxicity
New chemicals based on strobilurin chemistry:
BASF: Strobilurin based fungicide mobile on wax layer moves to new growth though not truly systemic.(Mildew)
Bayer: Kresoxim (mildew , net blotch in barley and rynchosporium)
Bayer: Spiroxamine
Dow Elanco: Quinoxyfen (mildew)systemic action.
Ciba Geigy: Cyprodinil (eyespot wheat and rye strains net blotch of barley and mildew)
Zeneca: Strobilurin based broad spectrum
Copyright © 1996 Anthony Wooldridge
This Home Page was created by WebEdit, 10 November 1996
Most recent revision 10 November 2002