The new generation of hybrid plants in the greenhouse. Credit: UZH In today's agriculture, hybrid plants are crucial for the sufficient production of food, feed, fuel and fiber. These crosses between two different varieties are deemed particularly hardy and far more productive than their thoroughbred parent generations. Thanks to hybrid plants, the harvests from types of cereal crop, such as corn, can be more than doubled. However, the positive properties are already lost in the next generation, which is why hybrid seeds need to be reproduced annually. These crosses are costly and time-consuming and farmers are reliant on new seeds every year. Back in the 1930s, two Russian scientists came up with a proposal to simplify this elaborate process: If the first generation of crosses, the so-called F1 hybrid, were able to reproduce asexually, it would retain their increased efficiency. Some plant species naturally reproduce by cloning their seeds, which is referred to as apomixis. The theory that apomixis might preserve the properties of hybrid plants, however, had never been tested in an experimental setup - until now: Professor Ueli Grossniklaus and his team from the Department of Plant and Microbial Biology at the University of Zurich have found proof. "Based on hybrid plants that reproduce apomictically, we demonstrated that the offspring also exhibit the desired biological properties," explains first author Dr. Christian Sailer. "We managed to fix the hybrids' particular efficiency." The plants achieve the same size and yield for at least two more generations. This is in stark contrast to the individual plants of the following generation of conventional F1 hybrids used in agriculture, which differ significantly. Sailer's publication is a key, much-anticipated contribution towards apomixis research and its potential application as it was previously unclear whether the fixation of the genotype would suffice to preserve the advantageous properties of hybrids for generations. For their experiments, the research team created 11 new hybrids using natural apomictic mouse-ear hawkweed (Hieracium pilosella) and reproduced them for two generations through the natural cloning of the seeds. 20 different properties were measured and tested to see if they changed from one plant generation to the next. Moreover, both generations of the same clone were grown in the greenhouse at the same time to expose them to the same environmental conditions and exclude various factors, such as temperature, water and light. More affordable and hardy seeds for small farms "If this special reproduction method could be used in crops, it would slash the cost of producing F1 hybrid seeds," explains Professor Ueli Grossniklaus. "It's not just seed producers who stand to bene-fit, but also subsistence farmers in developing countries." Nowadays, these small farmers usually use less productive native crops for their own personal use. Apomictic reproduction would offer them more affordable access to more productive and hardy hybrid strains. And they would be able to use the seeds from the current harvest for sowing the following year without affecting the yield. According to Grossniklaus, however, its actual use in crops still needs to be tested in detail. More information: Christian Sailer, Bernhard Schmid, Ueli Grossniklaus. Apomixis allows the transgenerational fixation of phenotypes in hybrid plants. Current Biology, 28. Januar 2016. DOI: 10.1016/j.cub.2015.12.045
Lindow S.,Microbial Biology |
Newman K.,Microbial Biology |
Chatterjee S.,Microbial Biology |
Baccari C.,Microbial Biology |
And 2 more authors.
Molecular Plant-Microbe Interactions | Year: 2014
The rpfF gene from Xylella fastidiosa, encoding the synthase for diffusible signal factor (DSF), was expressed in 'Freedom' grape to reduce the pathogen's growth and mobility within the plant. Symptoms in such plants were restricted to near the point of inoculation and incidence of disease was two- to fivefold lower than in the parental line. Both the longitudinal and lateral movement of X. fastidiosa in the xylem was also much lower. DSF was detected in both leaves and xylem sap of RpfF-expressing plants using biological sensors, and both 2-Z-tetradecenoic acid, previously identified as a component of X. fastidiosa DSF, and cis-11-methyl-2-dodecenoic acid were detected in xylem sap using electrospray ionization mass spectrometry. A higher proportion of X. fastidiosa cells adhered to xylem vessels of the RpfF-expressing line than parental 'Freedom' plants, reflecting a higher adhesiveness of the pathogen in the presence of DSF. Disease incidence in RpfFexpressing plants in field trials in which plants were either mechanically inoculated with X. fastidiosa or subjected to natural inoculation by sharpshooter vectors was two- to fourfold lower in than that of the parental line. The number of symptomatic leaves on infected shoots was reduced proportionally more than the incidence of infection, reflecting a decreased ability of X. fastidiosa to move within DSFproducing plants. © 2014 The American Phytopathological Society. Source
News Article | April 22, 2008
Fujitsu released today a new desktop and refreshed most of its notebook line in Japan. Akihabara News has details on all of the changes. The Deskpower FMV F/A50 is an all-in-one PC with a 16-inch widescreen LCD. The design is clearly inspired by Apple. Specs for the F/A50 include 2.1GHz Core 2 Duo T8100, 2GB of memory a 250GB hard drive, and Intel integrated graphics. The LOOX R series 12.1-inch, Biblio MG series 13.3-inch and 14.1-inch, and NF series 15.4-inch models get updated processors, 2- to 4GB of memory, and larger hard drives. The tiny LOOX U series 5.6-inch UMPC and the NX series 17-inch model are unchanged. The LOOX R series also gets an LED-backlit display and comes in seven colors including . . . golden retriever?