Experiment confirms that insects play a key role in the pollination of cultivated plants
A lack of bees and other wild insects to pollinate crop plants can reduce harvest yields more drastically than a lack of fertilizer or a failure to provide the crops with sufficient water.
A bee of the genus Panurginus leaves an almond blossom in Northern California.
Photo: Alexandra-Maria Klein
When crops are adequately pollinated, on the other hand, the plants bear more fruit and their nutrient content changes. These are the findings of an experiment on almond trees conducted in California by the Freiburg ecologist Prof. Dr. Alexandra-Maria Klein and her colleagues from the USA.
The team published articles presenting their findings in the journals Plant Biology and PLoS ONE. Alexandra-Maria Klein will receive the 25,000-euro CULTURA Prize on Tuesday, 17 June 2014, for this and other research projects on the importance of insects for the pollination of crop plants. Conferred by the Alfred Toepfer Foundation, the prize recognizes European scientists for innovative and exemplary research approaches in the areas of nature conservation, agriculture and forestry, and related sciences.
Together with students and colleagues at the University of California, Berkeley, Alexandra Klein manipulated almond trees by preventing bees from pollinating blossoms with the help of cages, allowing the bees to pollinate the blossoms, or pollinating them by hand. In addition, the researchers watered and fertilized trees in accordance with local practices or gave them only little water or no fertilizer.
In the case of several almond trees, they combined the various manipulations in order to study in isolation and in combination the effects on harvest yield and the composition of nutrients in the nuts. The almond trees that were pollinated by hand produced the most nuts, but they were also very small.
By contrast, a tree that was left unpollinated hardly produced any nuts at all – but the few that it did produce were very large. The yield of the trees pollinated by bees was roughly 200 percent higher than that of self-pollinatedtrees.
Fertilization and watering only had an effect on harvest yield in combination with the pollination manipulations. However, the inadequately watered trees lost more leaves, and the leaves of the unfertilized trees increasingly turned yellow.
This led the scientists to the conclusion that an almond tree can compensate for a lack of nutrients and water in the short term by directing stored nutrients and water to the fruits but cannot compensate for insufficient pollination. Furthermore, the scientists demonstrated that the composition of nutrients differs depending on the pollination mode: Nuts from the self-pollinated trees contained a lower proportion of linoleic acid but a higher proportion of vitamin E.
Prof. Dr. Alexandra-Maria Klein | University of Freiburg
Perseus translates proteomics data
27.07.2016 | Max-Planck-Institut für Biochemie
Severity of enzyme deficiency central to favism
26.07.2016 | Universität Zürich
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.
While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.
Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.
Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...
Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases
Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...
15.07.2016 | Event News
15.07.2016 | Event News
11.07.2016 | Event News
27.07.2016 | Earth Sciences
27.07.2016 | Materials Sciences
27.07.2016 | Earth Sciences