No abstract

In sugar beet production, weed control is one of the most important and most expensive practices to ensure yield. Since glyphosate-resistant sugar beets are not yet approved for cultivation in the EU, little commercial experience exists with these sugar beets in Europe. Experimental field trials were conducted at five environments (Germany, Poland, 2010, 2011) to compare the effects of glyphosate with the effects of conventional weed control programs on the development of weeds, weed control efficiency and yield. The results show that the glyphosate weed control programs compared to the conventional methods decreased not only the number of herbicide applications but equally in magnitude decreased the dosage of active ingredients. The results also showed effective weed control with glyphosate when the weed covering was greater and sugar beets had a later growth stage of four true leaves. Glyphosate-resistant sugar beets applied with the glyphosate herbicide two or three times had an increase in white sugar yield from 4 to 18 % in comparison to the high dosage conventional herbicide systems. In summary, under glyphosate management sugar beets can positively contribute to the increasingly demanding requirements regarding efficient sugar beet cultivation and to the demands by society and politics to reduce the use of chemical plant protection products in the environment.

Sugarbeet apices were used as targets for particle bombardment with a microtargeting device. Before examining gene expression, particle penetration experiments were carried out. Transient GUS expression was detected within the first and second cell layers of the meristem. Dividing cells with GUS activity demonstrated that cells survived the bombardment procedure.

No abstract

The development and market introduction of H7-1, the first commercially relevant transgenic sugarbeet, is described. A gene which sequence had been modified to code for a glyphosate-insensitive 5-enolpyrovylshikimate-3-phosphate synthase (EPSPS) was transferred to sugarbeet cells using Agrobacterium-mediated transformation. Plants were regenerated from such cells and were submitted to rigorous testing of their molecular, physiological, agronomic, and ecological properties. Data from these analyses constituted the basis for the legal deregulation of an elite transformation event. As results of this registration process permits for the cultivation of H7-1 have been issued in the USA, Canada, and Japan. For import purposes, food and feed utilization permits are in place in more than 15 countries, including the EU. H7-1 plants were used as starting material for the development of varieties adapted to the respective agronomical requirements of the designated cultivation areas, making extensive use of markerassisted backcrossing (MABC) as one of the breeding tools. In addition to herbicide tolerance, numerous other transgenic traits are currently under development. Their prospects and technical concepts are briefly discussed.