Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Apple trees resistant to fire blight and apple scab

20.02.2006
Apple scab and fire blight are two of the most important diseases affecting apple trees.

The Venezuelan biologist, Alejandro Martínez Bilbao, has undertaken research into more than 200 types of apple tree, indigenous to Spain, in order to select those varieties resistant to these pathogens. One of the main conclusions of the PhD thesis of this biologist is that, in Navarre, there are 12 apple tree varieties capable of resisting these highly damaging pests. This is the first time in Spain that such a study has been carried out.

The PhD defended at the Public University of Navarre is entitled, “Evaluation of the resistance of autochthonous varieties in Spain to Fire Blight (Erwinia amylovora) and to Apple Scab (Venturia inaequalis)”.

The first measures against apple scab and fire blight

In 1996 a focus of fire blight appeared in Spain. This led government authorities to take a number of eradication measures, given the threat that the disease posed if it spread to other trees such as the pear. One of the decisions taken was to set up a research project, in which the Universities of Gerona, Valencia and Pamplona took part, in order to determine the class of apple trees that offered resistance or had low sensitivity to this pathogen. Some years later the study of the apple scab was included in the study, this being the other disease that most frequently attacks these types of fruit trees.

Both pests are highly damaging, although the fire blight has more serious consequences, given that it attacks all the plant’s organs. The first symptom observed is that the buds appear to be burnt. If the fruit tree is very sensitive to the bacteria, it may die; but, if it is not very sensitive, it can halt the progress of the pest. The apple scab acts in a different manner, focusing on the leaves and the fruit and, therefore, easier to control. The fungus causes a decrease in the size of the apple and deterioration in its overall aspect. Moreover, the leaves become full of dark stains.

One of the main methods to control fire blight and apple scab is based on the crop varieties that are resistant or have low sensitivity to this pest. In Navarre, the Technical Institute for Agricultural Management (ITGA) has a collection of 253 types of apple tree, autochthonous to Spain, providing a valuable source in the quest for solutions. Alejandro Martínez’s PhD analysed apple trees that the ITGA has on its experimental farm in Doneztebe/Santesteban and has confirmed that 12 Navarre varieties show resistance to both fire blight and apple scab. In the case of apple scab, the fruit trees have shown that they are totally resistant to this disease, while in the case of fire blight, it has been shown that the pathogen attacks them, but does not damage them as much as the rest of the trees.

The apple scab may be controlled by treatment with fungicide, but the problem is, if the plant is highly sensitive to the pest, it will need 15 treatments a year. This brings with it great environmental and economic consequences. Moreover, the continued use of insecticides may give rise to the appearance of strains resistant to the fungicides.

Although in a number of European countries and in the USA numerous studies on resistance of apple tree varieties to fire blight and apple scab have been undertaken, this is the first in Spain. It is true that field evaluations of these pests have been carried, but these were never transferred to the laboratory. The results that appear in the PhD were obtained by means of artificial inoculation.

Perspectives for the future

The ITGA tests were aimed at looking for new alternatives for the future. One line of research is the possibility of planning new varieties of apple trees resistant to apple scab and with low susceptibility to fire blight. The biologist has stated that this solution could be particularly interesting in ecological farming given that, in this type of market, the aim is to obtain fruit free of fungicides and other products. The problem with this alternative method is that it could create a resistant variety that is of no commercial use, i.e. that does not incorporate the specific commercial characteristics that give the fruit its specific taste and texture.

The other option is genetic enhancement. This involves achieving a mixture of varieties resistant to the diseases and varieties that contain the commercial characteristics that consumers like. It is precisely this second way that the Navarre Technical Institute for Agricultural Management is employing to find a mixture to produce cider. The project is currently in its study phase but it could be the long-term solution.

Garazi Andonegi | alfa
Further information:
http://www.basqueresearch.com/berria_irakurri.asp?Gelaxka=1_1&hizk=I&Berri_Kod=888

More articles from Agricultural and Forestry Science:

nachricht Cascading use is also beneficial for wood
11.12.2017 | Technische Universität München

nachricht The future of crop engineering
08.12.2017 | Max-Planck-Institut für Biochemie

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>