Variable ITS-copy number at different developmental stages of Meloidogyne hapla and M. chitwoodi

Quantitative polymerase chain reaction (qPCR) can be used for the accurate quantification of plant-parasitic nematodes from soil samples. Unlike the traditional Baermann funnel and centrifugal flotation techniques followed by visual enumeration, all developmental stages of plant-parasitic nematodes can be detected and quantified by using qPCR. However, little is known about the amount of DNA between different stages of plant-parasitic nematodes. Here, we show that ITS-copy number varies with developmental stage of Meloidogyne chitwoodi and M. hapla . The number of copies of ITS was lower in cell-stage eggs (51 ± 7.4 for M. hapla and 31 ± 6.0 for M. chitwoodi ) than in second-stage juveniles (1345 ± 130.6 for M. hapla and 1036 ± 140.3 for M. chitwoodi ) and females (19,508 ± 3367.3 for M. hapla and 9049 ± 316.7 for M. chitwoodi ).