Population dynamics of Globodera pallida (Nematoda: Heteroderidae) on two potato cultivars in natural field conditions in Balearic Islands, Spain

Abstract

Globodera pallida is a serious economic pest in worldwide planting of potatoes due to the severe crop losses they can cause. This study aimed to determine the relationship between soil temperature [degree-day accumulation (DD4)]and population development of G. pallida under the agroecological conditions of the Balearic Islands, Spain. Population changes were studied in ‘Marfona’ and ‘Maris Peer’ potato cultivars for three growing seasons. Differences in thepattern of occurrence of nematode life stages on the two potato cultivars were observed. In Maris Peer trials,  secondstage juveniles (J2) hatching occurred about one month after planting (29 and 35 days), J2 root invasion at 57-56 days, and females in roots at 77 days with 540 DD4. In Marfona trials, these nematode stages occurred at 18-31days, 45-52 days and 59-73 days, the last one with 400 DD4. Hence, in Mallorca, G. pallida populations require at least 100 DD4 more in Maris Peer early potato than in the Marfona to reach the adult stage. Senescence in Maris Peer crops happened before most of the females have become brown cyst, suggesting that in this area the Maris Peer early cultivar could exert trap crop effects. The Marfona crop yield obtained at highest level of nematode infestation may indicate thatMarfona seems to be more tolerant to G. pallida than Maris Peer. The results contribute to the knowledge of thermaltime requirements of G. pallida populations under Mediterranean environmental conditions and can be a valuable tool to develop potato cyst nematode control strategies.