Temperature Dependent Reproduction and Survival of the Soil Nematode Pristionchus maupasi In Vitro

ABSTRACT

In the present study, the reproduction potential and survival capability of the soil nematode Pristionchus maupasi was followed in 10 cm² Petri dishes at different constant temperatures: 5, 10, 15, 20, 25 and 30 °C. The experiment started by placing nematode eggs on each dish. The minimum number of days from eggs, at start, to adult egg producing nematodes, decreased from 7 days at 10°C to 3 days at 25°C. At 5°C no eggs hatched, and at 30°C the released larvae did not develop into egg producing adults. After 7 days all eggs had hatched in the interval between 15 and 30 °C and 87 % at 10 °C. From hatched eggs the 1^st generation nematodes evolved.

At day 4, the number of 1^st generation nematodes was almost similar at temperatures ranging from 10 to 25 °C, while the number at 30 °C was significantly lower. The 1^st generation adult nematodes gave rise to a 2^nd generation, which did not develop to fertility, but became arrested 3^rd stage “dauerlarvae”, maybe due to reduced food supplies and increased concentration of wastes. From 100 ‘eggs at start’, 10000 to 14000 2^nd generations “dauerlarvae” developed at temperatures between 10 and 20°C. In the interval from 10 to 25 °C, a substantial number of these survived more than 2 months.

Keywords: