Chickpea (Cicer arietinum ‘Anna CP’) S. Halley and J. Lukach

Ascochyta blight; Ascochyta rabiei Langdon Research Extension Center

North Dakota State University

Langdon, ND 58249

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 North Dakota, NDSU Extension, were followed. Fungicides were applied by pressurized CO₂ backpack sprayer at 18 GPA at 40 psi with hydraulic XR8002 nozzles oriented vertical. Plots were harvested with a Hege plot combine 5 Sep. The grain sample was cleaned and processed for yield. Data was analyzed with the general linear model in SAS. Least significant differences were used to compare means at the 5% probability level.

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.