Constitutive overexpression of a protein involved in plant defense mechanisms to disease is one of the strategies proposed to increase plant tolerance to fungal pathogens. A hybrid endochitinase gene under a constitutive promoter was introduced by Agrobacterium-mediated transformation into a winter-type oilseed rape (Brassica napus var. oleifera) inbred line. Progeny from transformed plants was challenged using three different fungal pathogens (Cylindrosporium concentricum, Phoma lingam, Sclerotinia sclerotiorum) in field trials at two different geographical locations. These plants exhibited an increased tolerance to disease as compared with the nontransgenic parental plants.

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The impact of genetically modified oilseed rape (Brassica napus L.) on the foraging behaviour of honey bees (Apis mellifera L.) was evaluated on two different lines transformed to express constitutively heterologous chitinase in somatic tissue for enhanced disease resistance. Experiments were conducted in confinement in an indoor flight room with controlled conditions and in an outdoor flight cage with conditions more representative of the open environment. Foraging behaviour was analysed by observations of general bee behaviour (total number of visits) and of individual bee behaviour (using a video camera coupled with a special software program to process the data). The plants were analysed in terms of nectar quantity and quality (nectar volume and sugar content). The results showed no effects on bee foraging behaviour due to the modification of the genome of these plants by the introduction of a chitinase gene even though some differences between lines were found in the nectar. The methods applied in this original approach for the evaluation of the impact of genetically modified oilseed rape were shown to be sufficiently sensitive to detect changes in bee behaviour resulting from differences between plants.

The coding sequence of Δ9‐stearoyl‐(acyl carrier protein) desaturase from Ricinus communis was introduced into sunflower, under the control of seed‐specific promoter and terminator sequences of the late embryogenesis abundant gene from sunflower, Hads10. Two independent primary transformants contained three and six copies of the T‐DNA, as demonstrated by hybridization using nptII as a probe. The transgene proved genetically stable and was transmitted as a Mendelian trait. Transcript analysis of the heterologous Δ9‐stearoyl‐(acyl carrier protein) desaturase under control of the Hads10 promoter verified tissue‐specific expression in the developing embryos and not in the leaves. Fatty acid composition of the seed oil was followed over five generations under greenhouse and open field conditions. Some of the transgenic lines produced oil with a significantly reduced stearic acid content compared with non‐transformed plants under greenhouse and field conditions. However, additional studies need to be performed to assess whether or not physiologically stable lines can be developed from these transgenic lines.