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Oilseed rape (Brassica napus) is an economically important crop. In a temperate climate, powdery mildew Erysiphe crucifertaum can drastically reduce its yield. Nevertheless, cultivars resistant to this fungal disease have not yet been selected. Glutathione S-transferase GSTF11 is involved in glucosinolate (GSL) biosynthesis and response to stress, including fungal deceases. However, the impact of exogenous GSTF11 gene expression on resistance to powdery mildew has not yet been confirmed and requires further investigation. Transgenic B. napus was generated for this purpose. It demonstrated increased GST activity and a higher GSH:GSSG ratio under normal conditions. Powdery mildew Erysiphe crucifertaum caused 50% mortality in wild type (WT) plants. In most of transgenic plants, mycelium growth was inhibited. The infection contributed to higher GSTF11 expression and increased levels of glutathione (GSH) and oxidized glutathione (GSSG) in both transgenic and WT plants. In contrast, GSTF11 mRNA content, GST activity and GSSG level were lower only in WT plants. In transgenic plants, increased resistance to powdery mildew correlated with a lower GSH:GSSG ratio, indicating a higher content of neutralized toxic molecules. GSTF11 expression was also affected by cold stress, but not drought. At −1 °C, the expression level increased only in transgenic plants. Therefore, GSTF11 appears to be nonspecific and is able to protect plants under several types of stress. This gene could be used as a target in the production of stress tolerant cultivars.

We identified Populus nigra auxin-regulated gene involved in organ size (PnARGOS)-LIKE encoding one of organ size related (OSR)-proteins in black poplar which is homologous to AtARGOS and AtARGOS-LIKE genes of Arabidopsis thaliana. ABRE-like, G-box, GATA and Ibox motifs were discovered in the promoter region of poplar ARGOS-LIKE gene. In wild type aspen (Populus tremula) plants, ortholog of PnARGOS-LIKE gene (PtrARGOS-LIKE) was noticeably expressed in the actively dividing and expanding young leaves and calli, whereas its mRNA content increased in response to exogenous 6-benzylaminopurine, 1-naphthaleneacetic acid, and 24-epibrassinolide. The expression of PtrARGOS-LIKE gene was reduced under salinity treatment. In addition, we generated transgenic tobacco and aspen plants with up-regulated expression of PnARGOS-LIKE gene. Constitutive expression of the gene contributed to an increase in size of stems and leaves of transgenic tobacco plants. In transgenic aspen constitutive expression of PnARGOS-LIKE gene promoted an increase in the frequency of leaf initiation and in the leaf length and area. The size of transgenic tobacco and aspen leaves increased due to the enlargement of individual cells. The results show the significance of PnARGOS-LIKE gene for the control of leaf initiation and organ growth by cell expansion in poplar.

Background. The peculiarities of transcription activity of genes taking part in Colorado potato beetle diapause regulation have been investigated under the laboratory conditions in winter diapause initiation phase and in the middle of winter. Materials and Methods. Excerpt of summer generation (2015 year.) adults divided in active and inactive individuals in groups treated or untreated by fipronil in sublethal concentration (0.0001% a.i.) in the diapause initiation and maintenance phases. Quantitative real-time PCR used for comparing evaluation of transcription activity in muscles and gonads tissues for genes DP1, fer, DAT1, DAT2, EcR, Ldace-1 and rdl.  Results. In gonads of active adults unlike the quiescent ones detected presence of rdl subunit of GABA-А receptor mRNA. In the middle of diapause maintenance phase in fipronil-treated adults revealed the increasing of mRNA content in muscles and gonads for genes of reserve proteins DP1, defensive proteins DAT1, DAT2, ferritin fer, gene of ecdysone receptor EcR and gene coding the acetylcholinesterase Ldace-1. Conclusion. The assumption advanced about the fipronil blocking the GABA-receptor binding thereby has significant impact to regulation processes accompanying the development of diapause states.