The effect of non-native Solanaceous trap crops upon PCN Globodera pallida hatch induction under in vitro and in vivo conditions

摘要

Although the potato cyst nematodes (PCN), Globodera pallida (Stone) and Globodera rostochiensis (Wollenweber), are widely regarded as serious agricultural pests, progressive knowledge of their biology and distribution is necessitating a change in theway that PCN management is conducted. In the UK, the widespread cultivation of G. rostochiensis resistant potato varieties (ineffective for G. pallida) has selected for the multiplication of virulent G. pallida populations. Few fresh potato varieties areavailable with G. pallida resistance. Recent research by Trudgill etal. (2014) highlights the average crop rotation (6-7 years) to be unsustainable as a result of the species' low spontaneous hatch. Furthermore, with recent nematicide revocations, thereare a limited number of chemical control options left. Sustainable alternatives are urgently required. One strategy is trap cropping.Trap cropping involves the growth of a non-host or resistant plant, in advance of the main potato crop, to stimulate nematode hatch whilst suppressing further juvenile development and multiplication. In theory, this should allow for the gradual reductionof a PCN population. The first Solanaceous species to be explored as a trap crop was S. tuberosum. Early research demonstrated potato trap crops to achieve a 69-87% PCN reduction under Dutch conditions (Scholte, 2000). Resistant and non-resistant varieties were also successfully applied to a range of population densities (from 45^150 eggs g soil1) and soil types within the UK (Halford etal., 1999). However, an optimal growing period was critical to success. Potato trap crops must be grown long enough to induce a high degree of juvenile hatch but short enough to prevent accidental multiplication in the field. Volunteer potato plants (grown from unharvested tubers) may also act as a further point source for PCN multiplication.