
TY  - JOUR
A1  - McKay, AG 
A1  - Floyd, RM 
A1  - Boyd, CJ 
T1  - Phosphonic acid controls downy mildew (<I>Peronospora parasitica</I>) in cauliflower curds
JF  - Australian Journal of Experimental Agriculture
JO  - Aust. J. Exp. Agric.
Y1  - 1992
VL  - 32
IS  - 1
SP  - 127
EP  - 129
KW  - 
UR  - https://doi.org/10.1071/EA9920127 
N2  - Postharvest development of downy mildew (Peronospora parasitica) symptoms in export cauliflower curds has resulted in economic losses to growers in south-western Australia. Neutralised phosphonic acid sprays applied onto cauliflowers in the field within 3 weeks of harvest reduced this disease. Two applications of 2.4 kg a.i./ha, 21 and 7 days before harvest, reduced the incidence of curds affected by downy mildew from 92% in untreated plots to 8%. The maximum phosphonate residue in curds at harvest was 12 µg/g, while control curds contained no detectable phosphonate. No effects of phosphonic acid on crop appearance or maturity were observed, and while a small (8%) reduction in curd weight was significant (P = 0.039), there was no yield trend with increasing phosphonic acid rate. 
ER  -

