Cytokinins are plant hormones regulating cell division and differentiation.
Most developmental events from germination, vegetative morphogenesis to seed
and fruit set are influenced by cytokinins. t,ns-Zeatin is the major natural
occurring cytokinin. Its isomer, cis-zeatin, and its derivatives are usually present in
low quantities and have traditionally been considered as...
Stable expression of transgenes is required for commercial uses of genetically engineered trees. To better understand the stability of transgene expression under field conditions, we studied transgene expression and RNA interference (RNAi)-induced transgene suppression in 2,480 transgenic poplars (460 transgene insertion events) over three years. Stability of expression was assessed...
To reduce the environmental impacts caused by gene flow from transgenic trees, reproductive sterility genes have been developed that use a floral regulatory element linked to a cell toxin. This results in dysfunction or ablation of floral tissues, causing sterility. However, floral promoters often permit low levels of expression in...
Wheat (Triticum aestivum L.) is one of the most important crops in the world. It has been and continues to be one of the main sources of food for humans and animals. Although traditional wheat breeding has contributed greatly to the improvement of wheat both in productivity and biotic/abiotic stress...
Creeping bentgrass (Agrostis stolonifera L.) is an outcrossing, small- seeded, perennial grass that can establish outside of cultivation and has several compatible relatives. Glyphosate is a nonselective, broad spectrum, herbicide. Transgenic glyphosate-resistant (GR) creeping bentgrass (GRCB) was developed by The Scotts Company and Monsanto, but is still under USDA-APHIS regulated...
Hybrid poplar plantations (Populus trichocarpa x Populus deltoides) are a relatively new feature on the landscape in the Pacific Northwest of the United States, and these plantations may soon include genetically engineered trees. Meanwhile, many wild poplar populations (Populus spp.) are highly degraded due in part to logging, dams, grazing,...
The effect of increased manganese superoxide dismutase (Mn-SOD) and cytosolic ascorbate peroxidase (cAPX) on various abiotic stresses was studied using transgenic tomato (Lycopersicon esculentum) plants. Transformants were selected in vitro based on kanamycin resistance, confirmed by PCR and northern blot analyses. Northern blots showed an enhanced gene expression of Mn-SOD...
Epigenetic mechanisms are important for control of plant development, and may play a particularly important role in trees given their long life cycles and distinctive and stable tissue types. To help understand the role of epigenetics in tree development, we produced transgenic poplars with reduced activity of the DDM1 genes,...
Society uses massive quantities of wood fiber in production of paper, and demand for fiber is projected to increase further as production of biofuels from fermentation of plant cellulosic materials increases. Because these end uses generally require the costly step of removing of lignin, wood with reduced or more easily...
Raspberries have been popular since the time of the ancient Greeks. Red raspberries are cultivated throughout the world, particularly in the Pacific Northwest region of the United States and Canada. The raspberry bushy dwarf virus (RBDV) causes significant reduction in yield and crumbly fruit in raspberries, blackberries and raspberry-blackberry hybrids....
In the Willamette Valley of Oregon, a combination of the need for rotational crops and an increased desire for biofuel production created interest in planting Brassica napus (canola). However, questions were raised arisen over the potential damage canola production could have on the preexisting Brassica vegetable seed industry. To address...
