Increased Incidence of Erwinia Soft-rot on Calla Lilies in the Presence of Phosphorous |
| |
| Authors: | JA Gracia-Garza TJ Blom W Brown DP Roberts K Schneider M Freisen D Gombert |
| |
| Institution: | (1) Institute of Plant and Microbial Biology, Academic Sinica, Nankang, Taipei, 11529, Taiwan, ROC;(2) Department of Life Science, National University of Kaohsiung, Kaohsiung, 811, Taiwan, ROC; |
| |
| Abstract: | Erwinia soft-rot is an important disease of many ornamental potted crops and is one of the most limiting factors in greenhouse calla lily (Zantedeschia spp.) production. Experiments were conducted to test the effect of phosphorous added to soil-less mixes or to nutrient solutions used for irrigation on soft-rot caused by Erwinia carotovora subsp. carotovora (Ecc). Soft-rot incidence increased to 51% when soil-less mix was amended with superphosphate in comparison to regular soil-less mix (no superphosphate added) (31%). In contrast, addition of phosphorous in the nutrient solution met the phosphorous needs of the plant without enhancing soft-rot. Plant height, fresh mass, and number of flowers per plant were greater in calla lilies irrigated with nutrient solution containing phosphorous than no phosphorous treatments. Similar results were obtained in tests conducted in a commercial greenhouse with larger sample size. No statistical differences were found between tubers sprayed with water (control) or with a 0.5 mM solution of KH2PO4 in laboratory experiments to determine the effect of phosphorous on tuber root development. In other experiments, tubers were sprayed with either water, a bacterial cell suspension 1 × 102 cfu ml–1, a solution of 0.5 mM KH2PO4, or a suspension of bacteria in KH2PO4. The results from these tests showed a significant increase of soft-rot development in tubers treated with the suspension of Ecc prepared in a solution of KH2PO4 relative to other treatments. Further laboratory tests indicated that enzymatic activity (polygalacturonase and pectate lyase) of Ecc increased when grown in the presence of phosphorous. These experiments suggest that increased soft-rot in the presence of phosphorous is due to increased virulence of Ecc. |
| |
| Keywords: | calla lily Erwinia carotovora subsp carotovora nutrient solution superphosphate Zantedeschia spp |
| 本文献已被 SpringerLink 等数据库收录！ |
|
