Globodera pallida is a major nematode pest of potato and is of great economic importance for the potato industry. Assessing potato yield loss caused by the Idaho G. pallida population under field conditions was not performed due to its quarantine status in Idaho where it is prohibited by regulatory statutes to grow potato in any infested fields.
A predictive risk model analysis was performed to: (i) determine the effect of the Idaho population of G. pallida on potato yield; (ii) estimate reproduction rate from different initial nematode densities; and (iii) simulate potato yield losses in Idaho field conditions by integrating the coefficients of potato yield into the SUBSTOR-DSSAT crop simulation model.
Experiments were conducted under greenhouse conditions using five levels of initial densities in soil (0, 10, 20, 40 and 80 eggs/g soil).
The model showed that fresh tubers reached a maximum yield of 96 ton/ha in non-infested soil. Based on the greenhouse trials, the model predicted a minimum yield of 12 and 58 ton/ha in trial 1 and trial 2/3 respectively, when initial nematode density was 80 eggs/g soil.
In trial 1, fresh tuber weight was significantly reduced by 44% at 40 eggs/g soil and by 87% at 80 eggs/g soil, and 20% at 40 eggs/g soil and by 39% at 80 eggs/g soil in trial 2/3.
The researchers say the outputs of this study should facilitate common understandings between regulators, policymakers and potato growers on the challenges and opportunities for controlling this economically important pest in Idaho.
Source and further details: APS Publications