Temperature-based Prediction of egg-mass production by Meloidogyne incognita.
A maturation-rate relationship for Meloidogyne incognita on Lycopersicon esculentum 'Rutgers' was derived and used to estimate harvest dates for maximum egg hatch from laboratory cultures at ambient temperatures. Daily maturation increments were totaled (nematode maturation total, NMT) and correlated with hatch from isolated white, yellow, and amber egg masses. Hatch per mass fluctuated periodically from ca. 1.0 NMT, when egg masses were first visible, to 2.5 NMT by which time plants showed stress. Maximum yields from white and yellow masses occurred, with a shorter than expected periodicity, at 1.5-1.8 and 2.1-2.2 NMT. White masses decreased from 90% of the total masses at 1.0 NMT to 5% at 2.5 NMT, as the proportion of yellow and amber masses increased concomitantly. Harvested masses per gram of root varied from 97 to 276; hatch per gram of root, 11,000 to 86,000.
Carlson
D G
DG
U.S. Department of Agriculture,Peoria, Illinois 61604, USA.
Rothfus
J A
JA