Copy Number Variation in Acetolactate Synthase Genes of Thifensulfuron-Methyl Resistant (Shortawn Foxtail) Accessions in Japan.

Severe infestations of (shortawn foxtail), a noxious weed in wheat and barley cropping systems in Japan, can occur even after application of thifensulfuron-methyl, a sulfonylurea (SU) herbicide. In the present study, nine accessions of growing in a single wheat field were tested for sensitivity to thifensulfuron-methyl. Seven of the nine accessions survived application of standard field rates of thifensulfuron-methyl, indicating that severe infestations likely result from herbicide resistance.

Cytochrome P450 genes induced by bispyribac-sodium treatment in a multiple-herbicide-resistant biotype of Echinochloa phyllopogon.

Background: Incremental herbicide metabolism by cytochrome P450 monooxygenases (P450s) has been proposed as the basis for resistance to bispyribac-sodium (bispyribac) in a multiple-herbicide-resistant biotype of Echinochloa phyllopogon. Upon exposure to bispyribac, strong induction of bispyribac-metabolising P450 activity has been reported in the resistant line, indicating that P450s induced by bispyribac are involved in the bispyribac resistance.

Results: A polymerase chain reaction (PCR)-based cloning strategy was used to isolate 39 putative P450 genes from the bispyribac-resistant line of E.

Three-dimensional prediction of maize pollen dispersal and cross-pollination, and the effects of windbreaks.

With the extensive adoption of transgenic crops, an understanding of transgene flow is essential to manage gene flow to non-GM crops. Thus, a flexible and accurate numerical model is required to assess gene flow through pollen dispersal. A three-dimensional atmospheric model combined with a diffusion transport model would be a useful tool for predicting pollen dispersal since it would be flexible enough to incorporate the effects of factors such as the spatial arrangement of crop combinations, land use, topography, windbreaks, and buildings.

Germination characteristics of native Japanese dandelion autopolyploids and their putative diploid parent species.

Germination characteristics of native Japanese Taraxacum lineages of Taraxacum platycarpum (diploid), T. venustum (triploid and tetraploid), and T. albidum (pentaploid) have been studied at different temperatures.

Hybridization between European and Asian dandelions ( Taraxacum section Ruderalia and section Mongolica)2. Natural hybrids in Japan detected by chloroplast DNA marker.

Natural hybridization in Taraxacum between native sexual diploids and introduced agamospermous triploids occurring in Japan was studied by means of chloroplast DNA (cpDNA) marker. We first determined the nucleotide sequences between trnT (UGU) and trnF (GAA) of cpDNA for 22 plants obtained from Japan and Europe. The sequences analyzed were about 1,574 base pairs long.