Spontaneous hybridisation between vegetable crops and weeds. 1: Garden radish (Raphanus sativus L.) and wild mustard (Sinapis arvensis L.)

Abstract

In order to assess the risk of commercial F1 hybrid seed contamination due to outcrossing on male sterile radish line pollinated by Wild mustard, two isolated field experiments were performed in the presence or absence of garden radish pollen. Additionally, spontaneous wild radish plants were observed under 200 m away from both fields. Seeds were harvested on the female radish line and sieved. Isozyme analyses combined with cytogenetical characterisation revealed that morphological observations were not efficient enough to distinguish the interspecific hybrids among the seedlings obtained. The radish-wild mustard interspecific hybrid production was higher without than with radish pollen competition: 42 and 3 interspecific hybrid seeds per 1 000 seeds were observed, respectively. Numerous cultivated-wild radish hybrids were observed from the two experiments without and with radish pollinator: 551 and 144 per 1 000 seeds, respectively. Sieving seems to be efficient m preventing the commercialisation of cultivated radish-wild mustard hybrids.