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Taller, J.

Publications and source records attributed to Taller, J..

2 recordsLinked to original sources

Evaluation of acaricidal activity of lithium-chloride against Tetranychus urticae (Acari: Tetranychidae)

Tetranychus urticae is a severe threat and a major source of yield loss in some agricultural and horticultural crops. Control is greatly complicated due to the hidden lifestyle of the species. In addition to its direct damage, it is considered a vector for several viruses. The number of active substances used against it is limited, and the development of resistance means that sustainable control is not achieved. Therefore, there is a continuous need for new active substances. Lithium salts have been shown to be a promising alternative to control Varroa destructor, an apicultural mite pest. Therefore, in the present study, we investigated whether the contact efficacy of lithium chloride extends to other agricultural mite pests, such as the two-spotted spider mite. In the present pilot study, we report for the first time that the efficacy of lithium chloride extends to the two-spotted spider mite, showing 100% mortality at concentrations of 5.52 M, 2.76 M, and 1.38 M. It is to note, however, that the experiments did not cover residue and practical application aspects, and further extensive studies are needed in this area to clarify the relevance of the practical sub-classification.

zoology↗

Mapping and DNA sequence characterisation of the Rysto locus conferring extreme virus resistance to potato cultivar ‘White Lady’

Virus resistance genes carried by wild plant species are valuable resources for plant breeding. The Rysto gene, conferring a broad spectrum of durable resistance, originated from Solanum stoloniferum and was introgressed into several commercial potato cultivars, including White Lady, by classical breeding. Rysto was mapped to chromosome XII in potato, and markers used for marker-assisted selection in breeding programmes were identified. Nevertheless, there was no information on the identity of the Rysto gene. To begin to reveal the identification of Rysto, fine-scale genetic mapping was performed which, in combination with chromosome walking, narrowed down the locus of the gene to approximately 1 Mb. DNA sequence analysis of the locus identified six full-length NBS-LRR-type (short NLR-type) putative resistance genes. Two of them, designated TMV2 and TMV3, were similar to a TMV resistance gene isolated from tobacco and to Y-1, which co-segregates with Ryadg, the extreme virus resistance gene originated from Solanum andigena and localised to chromosome XI. Furthermore, TMV2 of White Lady was found to be 95% identical at the genomic sequence level with the recently isolated Rysto gene of the potato cultivar Alicja. In addition to the markers identified earlier, this work generated five tightly linked new markers which can serve potato breeding efforts for extreme virus resistance.

plant biology↗