Summary: The breeding of plantation forestry trees for the possible afforestation of marginal land would be one approach to addressing global warming issues. Here, we developed novel transgenicEucalyptustrees (Eucalyptus camaldulensisDehnh.) harbouring anRNA‐Binding‐Protein(McRBP) gene derived from a halophyte plant, common ice plant (Mesembryanthemum crystallinumL.). We conducted screened‐house trials of the transgenicEucalyptususing two different stringency salinity stress conditions to evaluate the plants’ acute and chronic salt stress tolerances. Treatment with 400 mM NaCl, as the high‐stringency salinity stress, resulted in soil electrical conductivity (EC) levels >20 mS/cm within 4 weeks. With the 400 mM NaCl treatment, >70% of the transgenic plants were intact, whereas >40% of the non‐transgenic plants were withered. Treatment with 70 mM NaCl, as the moderate‐stringency salinity stress, resulted in soilEClevels of approx. 9 mS/cm after 2 months, and these salinity levels were maintained for the next 4 months. All plants regardless of transgenic or non‐transgenic status survived the 70 mM NaCl treatment, but after 6‐month treatment the transgenic plants showed significantly higher growth and quantum yield of photosynthesis levels compared to the non‐transgenic plants. In addition, the salt accumulation in the leaves of the transgenic plants was 30% lower than that of non‐transgenic plants after 15‐week moderate salt stress treatment. There results suggest thatMcRBPexpression in the transgenicEucalyptusenhances their salt tolerance both acutely and chronically.

Novel transgenic Eucalyptus camaldulensis trees expressing the bacterial choline oxidase A (codA) gene by the Cauliflower mosaic virus (CaMV) 35S promoter and the Arabidopsis thaliana heat shock protein (HSP) terminator was developed. To evaluate the codA transcription level and the metabolic products and abiotic stress tolerance of the transgenic trees, a six-month semi-confined screen house cultivation trial was conducted under a moderate-stringency salt-stress condition. The transcription level of the CaMV 35S promoter driven-codA was more than fourfold higher, and the content of glycine betaine, the metabolic product of codA, was twofold higher, with the HSP terminator than with the nopaline synthase (NOS) terminator. Moreover, the screen house cultivation revealed that the growth of transgenic trees under the salt stress condition was alleviated in correlation with the glycine betaine concentration. These results suggest that the enhancement of codA transcription by the HSP terminator increased the abiotic stress tolerance of Eucalyptus plantation trees.

除草剤耐性遺伝子組換えトウモロコシGA21系統を分析対象とした新規系統特異的定量分析法を開発した．本分析法では，GA21ゲノム1ハプロイド当たり1か所のみ存在する挿入遺伝子配列と隣接するトウモロコシゲノムの境界部位をPCR反応によって増幅する．さらに，このPCR反応の増幅効率は内在性対照となるトウモロコシSSIIb 遺伝子の増幅効率と極めて近似するため，その内標比は理論値に近い値が得られた．また統計学的な分析値の評価を行った結果，本分析法はわが国の公定法に定められた他のGM定量分析法と同等以上の分析精度を示した．これら特性から，本法は多重リアルタイムPCR法による高効率的GMトウモロコシスクリーニング定量分析法に応用可能であると考えられる．

Delignification is effective for improving the saccharification efficiency of lignocellulosic biomass materials. We previously identified that the expression of a fungal laccase (Lac) fused with a bacterial cellulose-binding module domain (CBD) improved the enzymatic saccharification efficiency of rice plants. In this work, to evaluate the ability of the Lac-CBD fused chimeric enzyme to improve saccharification efficiency in a dicot plant, we introduced the chimeric gene into a dicot model plant, Arabidopsis thaliana. Transgenic plants expressing the Lac-CBD chimeric gene showed normal morphology and growth, and showed a significant increase of enzymatic saccharification efficiency compared to control plants. The transgenic plants with the largest improvement of enzymatic saccharification efficiency also showed an increase of crystalline cellulose in their cell wall fractions. These results indicated that expression of the Lac-CBD chimeric protein in dicotyledonous plants improved the enzymatic saccharification of plant biomass by increasing the crystallinity of cellulose in the cell wall.