Abstract

Pathogen buildup in vegetative planting material, termed seed degeneration, is a major problem in many low-income countries. When smallholder farmers use seed produced on-farm or acquired outside certified programs, it is often infected. We introduce a risk assessment framework for seed degeneration, evaluating the relative performance of individual and combined components of an integrated seed health strategy. The frequency distribution of management performance outcomes was evaluated for models incorporating biological and environmental heterogeneity, with the following results. (1) On-farm seed selection can perform as well as certified seed, if the rate of success in selecting healthy plants for seed production is high; (2) when choosing among within-season management strategies, external inoculum can determine the relative usefulness of 'incidence-altering management' (affecting the proportion of diseased plants/seeds) and 'rate-altering management' (affecting the rate of disease transmission in the field); (3) under severe disease scenarios, where it is difficult to implement management components at high levels of effectiveness, combining management components can be synergistic and keep seed degeneration below a threshold; (4) combining management components can also close the yield gap between average and worst-case scenarios. We also illustrate the potential for expert elicitation to provide parameter estimates when empirical data are unavailable.

Keywords

banana; cassava; environmental heterogeneity; positive selection; potato; root crops; seed degeneration; seed health; simulation models; sweetpotato; tuber crops; vegetative propagation; yam

Published in

Phytopathology
2017, Volume: 107, number: 10, pages: 1123-1135
Publisher: AMER PHYTOPATHOLOGICAL SOC

SLU Authors

• Yuen, Jonathan

  • Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network


Sustainable Development Goals

SDG13 Take urgent action to combat climate change and its impacts


UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1094/PHYTO-09-16-0340-R

Permanent link to this page (URI)

https://res.slu.se/id/publ/93199