Optimum Non-host Rotation Length for Nematode Management
Nov 30, 2001
- For any starting nematode population level, e.g., 5, 15, 50, 150 (panels
A,B,C,D), the population will increase at a predictable rate on a given host
crop, and then decline at a predictable rate under non-host crops.
- At some time in the future, the population will decline to, or below, the
level of the starting population. If a host crop is planted at that time, the
population should undergo the same increase and decline pattern as before
unless conditions in the field have changed in some dramatic way.
Consequently, a length of non-host rotation can be determined that will always
bring the population back to its starting level.
- So, if we calculate the length of non-host rotation necessary to achieve
this steady-state cycle for different starting population levels, we can
determine the returns from that number of years of non-host production. We can
also calculate the returns from the host crop at that starting population
- That allows determination of the population level and years of non-host
rotation for which average annual returns are maximized. The result will vary
with crop values of host and non-host crop, damage effect of the nematode on
the host crop, multiplication rate of the nematode on the host, and survival
rate of the nematode on the non-host.
Burt, O. R. and H. Ferris. 1996. Sequential decision rules for managing
nematodes with crop rotations. Journal of Nematology 28:457-474.