Chickpea (Cicer
arietinum ‘Anna CP’) S.
Halley and J. Lukach
Ascochyta
blight; Ascochyta rabiei
Chickpea
Response to Fungicide Application
Research results from 2002 indicate Chickpea is quite
susceptible to white mold, Sclerotinia
sclerotiorum (Lib) de Bary. Research on chickpea is complicated under wet
or humid environments because the species is very susceptible to Ascochyta
blight (Ascochyta rabiei (Passerini) Labrousse) making differentiation
between fungicide efficacies on the two diseases difficult to quantify. The
objective of this study was to evaluate fungicide applications to provide some
level of control of Ascochyta blight so studies to control white mold can
proceed.
A trial was designed as a randomized complete block
with 6 replicates to evaluate fungicides for control of Ascochyta blight.
Fungicides selected for evaluation included Ronilan (vinclozolin), Bravo
(chlorothalonil), JAU 6476 (prothioconazole), Headline (pyraclostrobin), Endura
(boscalid), Topsin M (thiophanate methyl), and Quadris (azoxystrobin). All the
treatments including the control received an application of Headline on 5 Jul
before flowering growth stage. Subsequent applications included an early flower
application (11 Jul), an application 7 days after early flower, or applications
at early flower and 7 days later. The cultivar ‘Anna CP’, a desi type, was
planted on a site previously cropped barley. Plots
were 7 rows wide spaced 6 inches 16 ft long. An additional row spaced 12 inches
from the plot border was included to reduce drift contamination to adjacent
plots. The seed was inoculated with Rhizobium
bacteria, 6 oz/1000 ft row. Recommended production practices for
RESULTS AND DISCUSSION
Ascochyta blight rating was the same on the control as
Ronilan, Headline, Endura, Topsin M, Bravo, and JAU 6476 applied at early
flower growth stage. Sequential fungicide applications of JAU 6476 and Quadris
at early flower and 7 days later reduced ascochyta from the control. No differences in yield or test weight were
detected. Further research will be needed to qualify effective fungicide
control of Ascochyta.
Fungicide |
Application |
Ascochyta |
Yield |
Test Weight |
|
Timing* |
Rating** |
|
|
|
|
0-9 |
cwt |
lb/bu |
Ronilan 50EG 12 oz/A |
Flower + 7 days |
5.2 |
1457 |
61.5 |
JAU 6476 480SC 5.7 fl oz/A |
Flower |
2.8 |
1716 |
62.0 |
Headline 2.09EC 8 fl oz/A |
7 days |
3.2 |
1736 |
61.4 |
JAU 6476 480SC 5.7 fl oz/A |
Flower + 7 days |
2.3 |
1965 |
62.2 |
Check |
|
4.2 |
1423 |
61.4 |
Endura 70DF 5.8 fl oz/A |
Flower + 7 days |
3.3 |
1792 |
62.1 |
Topsin M 70WP 1 lb/A |
Flower + 7 days |
3.0 |
1768 |
62.0 |
Bravo 82.5DF 1.6 lb/A |
Flower + 7 days |
3.5 |
1619 |
61.8 |
Quadris 22.9SC 9.6fl oz/A |
Flower + 7 days |
2.3 |
1991 |
61.8 |
|
|
|
|
|
LSD |
|
1.5 |
NS |
NS |
% C.V. |
|
39 |
22 |
1 |
*An application to control
ascochyta preceded flowering by about 5 days on all plots including the check.
**0-9 visual estimation, 0=no disease, 9=disease on all plants including stems, leaves, and pods.