Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-10T10:12:57.971Z Has data issue: false hasContentIssue false

Effect of Alternaria cassiae, Pseudocercospora nigricans, and Soybean (Glycine max) Planting Density on the Biological Control of Sicklepod (Senna obtusifolia)

Published online by Cambridge University Press:  12 June 2017

Robinson A. Pitelli
Affiliation:
Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil
R. Charudattan
Affiliation:
University of Florida, Gainesville, FL 32611
James T. Devalerio
Affiliation:
University of Florida, Gainesville, FL 32611

Abstract

The interactions of two fungal biocontrol agents, Alternaria cassiae and Pseudocercospora nigricans, and soybean planting density on sicklepod mortality and dry weight were studied in the field over 2 yr. The experimental field was divided into three equal areas: one without soybean and two where the soybean was sown in densities of 20 and 36 seeds per meter row with a 0.95-m row spacing. The fungi were sprayed alone or in a mixture at three growth stages of sicklepod plants grown at three levels of crop interference resulting from the three soybean planting densities. The fungal treatments were: an untreated control, A. cassiae (105 spores/m2), P. nigricans (3.3 g mycelium/m2), and the mixture of these two fungi. Sicklepod was at the cotyledonary leaf, two-leaf, and four-leaf stages when treated. Alternaria cassiae was most effective in reducing both sicklepod survival and dry weight. The mixture of P. nigricans and A. cassiae was generally comparable to but not better than A. cassiae alone in killing the weed (mortality) and reducing its growth (dry weight). Soybean density did not have significant effects on the mortality or the dry weight of sicklepod. Thus, there is no advantage to combining the highly effective biocontrol agent A. cassiae with the less effective P. nigricans or with soybean interference to control sicklepod. However, the results validate the efficacy of A. cassiae by itself as a bioherbicide.

Type
Research
Copyright
Copyright © 1997 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

Barreto, R. W., and Evans, H. C. 1992. Fungal pathogens of weeds collected in the Brazilian tropics and subtropics and their biocontrol potential. <i>In</i> Delfosse, E. S. and Scott, R. R., eds. Proceedings of the Eighth International Symposium on Biological Control of Weeds, Feb. 2–7, 1992, Lincoln University, Canterbury, New Zealand. Melbourne. Australia: DSIR/CSIRO. pp. 679691.Google Scholar
Charudattan, R., Walker, H. L., Boyette, C. D., Ridings, W. H., TeBeest, D. O., Van Dyke, C. G., and Worsham, A. D. 1986. Evaluation of <i>Alternaria cassiae</i> as a Mycoherbicide for Sicklepod (<i>Cassia obtusifolia</i>) in Regional Field Tests. Southern Cooperative Series Bull. 317. Auburn, AL: Auburn University. 19 p.Google Scholar
Cock, M.J.W., and Evans, H. C. 1984. Possibilities for biological control of <i>Cassia tora</i> and <i>C. obtusifolia.</i> Trop. Pest Manage. 30:339350.Google Scholar
Crowley, R. H., Teem, D. H., Buchanan, G. A., and Hoveland, C. S. 1979. Responses of <i>Ipomoea</i> spp. and <i>Cassia</i> spp. to preemergence applied herbicides. Weed Sci. 27:531535.Google Scholar
Gossett, B. J., 1981. Sicklepod—how to control in soybeans. Weeds Today 12:2930.Google Scholar
Griffin, J. L., Reynolds, D. B., Vidrine, P. R., and Bruff, S. A. 1993. Soybean (<i>Glycine max</i>) tolerance and sicklepod (<i>Cassia obtusifolia</i>) control with AC 263,222. Weed Technol. 7:331336.Google Scholar
Hofmeister, F. M., and Charudattan, R. 1987. <i>Pseudocercospora nigricans</i>, a pathogen of sicklepod (<i>Cassia obtusifolia</i>) with biocontrol potential. Plant Dis. 71:4446.Google Scholar
Holm, L., Doll, J., Holm, E., Pancho, J., and Herberger, J. 1997. World Weeds: Natural Histories and Distribution. New York: J. Wiley. 1129 p.Google Scholar
Jurair, A.M.M., and Khan, A. 1960. A new species of <i>Alternaria</i> on <i>Cassia holosericea</i> Fresen. Pak. J. Sci. Ind. Res. 3:7172.Google Scholar
Krista, L. J., Banks, P. A., and Karnok, K. J. 1988. Interference of soybean. <i>Glycine max</i>, cultivars with sicklepod. <i>Cassia obtusifolia.</i> Weed Technol. 2:404409.Google Scholar
Murray, D. S., Thurlow, D. L., and Buchanan, G. A. 1976. Sicklepod in the Southeast. Weeds Today 7:1214.Google Scholar
Pitelli, R. A., 1992. Weed–soybean interference studies in Brazil. <i>In</i> Cooping, L. G., Green, M. B., and Rees, R. T., eds. Pest Management in Soybean. London: Elsevier. pp. 282290.CrossRefGoogle Scholar
Rodrigues, B. N., and Almeida, F. L. 1995. Manual de Herbicidas. 2nd ed. Londrina, Parana, Brazil: IAPAR. 323 p.Google Scholar
Schott, P. E., Hanf, M., Schelberger, K., John, T., O'Neal, D., Schroeder, M., and Ware, T. 1994. Soybean: BASF code in decimal scale to define plant developmental stages. Parsippany, NJ: BASF 6 p.Google Scholar
E, Sherman. M., Thompson, L. Jr., and Wilkinson, R. E. 1983. Sicklepod (<i>Cassia obtusifolia</i>) management in soybeans (<i>Glycine max</i>). Weed Sci. 31:622627.Google Scholar
Walker, H. L., 1982. Seedling blight of sicklepod caused by <i>Alternaria cassiae</i>. Plant Dis. 66:426428.Google Scholar
Walker, H. I., and Boyette, C. D. 1985. Biocontrol of sicklepod (<i>Cassia obtusifolia</i>) in soybeans (<i>Glycine max</i>) with <i>Alternaria cassiae</i>. Weed Sci. 33:212215.Google Scholar