Author
NYANKANGA, RICHARD - CORNELL UNIVERSITY | |
WIEN, HANS - CORNELL UNIVERSITY | |
Olanya, Modesto |
Submitted to: Potato Research
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/8/2008 Publication Date: 8/12/2008 Citation: Nyankanga, R.O., Wien, H.C., Olanya, O.M. 2008. Effects of Mulch and Potato Hilling on Development of Foliar Blight (Phytophthora infestans) and Control of Tuber Blight Infection. Potato Research. 51:101-111. Interpretive Summary: Foliar and tuber blight caused by Phytophthora infestans accounts for significant losses in potatoes in field and storage environments, however; there is limited documentation of the utility of cultural practices such as mulching and potato hilling for late blight management. In this research, straw mulch application and potato hilling effects on blight development on Allegany and Katahdin cultivars were assessed in field experiments in New York in two year experiments. Potato hilling and mulching had no significant effect on foliar blight development. Foliar blight differed significantly (P<0.05) between cultivars, and ‘Allegany’ had lower disease compared to ‘Katahdin’. The mean tuber blight incidence for ‘Allegany’ and ‘Katahdin’ were 25% and 3%, respectively; in hilled plots. In the mulched plots, incidence of tuber blight averaged 33% for ‘Allegany’ and 10% for ‘Katahdin’, indicating that straw mulch was ineffective in tuber blight control. Tubers set at a soil depth of > 7 cm had lower tuber blight incidence than shallow tubers set at a depth of < than 7 cm. In both years, hilling provided partial protection of tubers and its effectiveness was limited, when favorable conditions for late blight development exist. These studies suggest that the use of cultivars with differences in foliar resistance to late blight in combination with potato hilling may be partially effective for tuber blight management. Technical Abstract: Foliar and tuber blight caused by Phytophthora infestans accounts for significant losses in potatoes in field and storage, however; limited research has documented the effect of cultural practices on late blight control. Field experiments were conducted for two years on Howard gravely loam soil in New York State to evaluate the effectiveness of mulching and hilling in preventing tuber blight infection for Allegany and Katahdin cultivars. Potato hilling and mulching had little effect on foliar blight development. The cultivar treatment significantly (P<0.05) affected foliage disease development and ‘Allegany’ had lower foliar late blight compared to ‘Katahdin’. Tuber blight incidence averaged 25% for ‘Allegany’ and 3% for ‘Katahdin’ in hilled plots while in the mulched plots, incidence of tuber blight averaged 33% for ‘Allegany’ and 10% for ‘Katahdin’, indicating that straw hay mulch was ineffective in tuber blight control. Tubers set at a soil depth of > 7 cm had lower tuber blight incidence than shallow tubers set at a depth of < than 7 cm. In both years, hilling provided partial protection of tubers but its effectiveness was limited in the presence of favorable conditions for late blight development. Even though large hills had numerically lower tuber blight than the medium hill size, tuber blight incidences among hill size treatments varied slightly. These studies suggest that the use of cultivars with foliage resistance to late blight in combination with cultural practices may provide partial effectiveness for tuber blight management. |