Transformation and mineralization of soil organic nitrogen by the humivorous larva of Pachnoda ephippiata (Coleoptera: Scarabaeidae) |
| |
Authors: | Xiangzhen Li Andreas Brune |
| |
Institution: | (1) Department of Horticulture, Michigan State University, East Lansing, MI 48823, USA;(2) Department of Crop and Soil Science and W.K. Kellogg Biological Station, Michigan State University, East Lansing, MI 48823, USA;(3) Department of Plant Pathology, Michigan State University, East Lansing, MI 48823, USA;(4) USDA-ARS, 1691 S 2700 W, Aberdeen, ID 83210, USA |
| |
Abstract: | In common bean (Phaseolus vulgaris L.), Fusarium root rot (caused by Fusarium solani f. sp. phaseoli) disease severity is increased by environmental factors that stress the plant. The current study used reciprocal grafting
techniques with the resistant cultivar FR266 and the susceptible cultivar Montcalm to determine if the genetic control of
resistance is conferred by the rootstock (root genotype) or the scion (shoot genotype) and if root vigor played a role in
resistance. The influence of a compacted layer on root and shoot genotype response and root rot resistance was studied. Root
rot resistance was found to be controlled by the root genotype, such that on a scale of 1 to 7 (severe disease) the FR266
root had an average score of 2.3 and the Montcalm root had an average score of 4.4. However, when grafted plants were grown
in the presence of a compacted layer, the FR266 root and/or shoot genotype in any graft combination with the susceptible Montcalm
had reduced root rot (score = 2.4 average) than the Montcalm self graft (score = 4.5). Root mass was shown to be controlled
by the root genotype in the absence of compaction such that the FR266 root was 26% larger that the Montcalm root when grafted
onto a FR266 shoot or a Montcalm shoot. When a compacted layer was present the root and shoot genotype both contributed to
root mass. Average root diameter was controlled by the shoot genotype, as the FR266 shoot grafted to Montcalm or FR266 roots
had thicker roots (average diameter 0.455 mm) than the Montcalm shoot (average diameter 0.418 mm). This study shows evidence
that root vigor in the presence of Fusarium disease pressure should be evaluated to effectively develop common bean lines
resistant to Fusarium root rot across a range of environments. |
| |
Keywords: | Root length Root diameter Soil compaction Reciprocal grafting |
本文献已被 SpringerLink 等数据库收录! |
|