Project start: 10.07.2017
Project end: 31.03.2019
Sponsor: Development agency for agribusiness

Phytoplasmas (Candidatus Phytoplasma) are cell wall-less plant-pathogenic bacteria which can colonize the phloem of more than 700 plant species including many economically important crops. They cause a wide range of symptoms that vary depending on the phytoplasma strain, their host plant, and environmental factors, and usually include yellowing of leaves, proliferation of shoots and stunting. In grapevine (Vitis vinifera) phytoplasmas cause diseases referred to as grapevine yellows. In other fruit trees like apple (Malus domestica) they cause apple proliferation and in pear (Pyrus) they lead to pear decline. Phytoplasmas are spread by phloem-feeding insect vectors, grafting, or vegetative propagation of infected plants. Control strategies for phytoplasmas currently rely only on preventing their spread, as there are no effective chemical plant protection products against phytoplasmas. In addition, phytoplasma diseases have long incubation periods of up to several months before symptoms can be observed. Therefore, this project aims to develop a fast and reliable molecular detection method for phytoplasmas based on LAMP and TaqMan assays, respectively, to be used in the production of vegetatively propagated crops like grapevine, apple, or pear.

Project start: 01.03.2016
Project end: 29.02.2020
Sponsor: European Commission

Coordinated by the University of Málaga, GoodBerry is focusing on strawberry, raspberry and black currant as model crop species and will study among others the adaptability of cultivars to different climatic conditions and the impact of these conditions on fruit quality. Global warming influences induction and initiation of flowers and the fulfillment of chilling requirement of the plants. First impairments were already observed in strawberries and currants under German growing conditions in the last decade. By cultivating well established cultivars of the three species with varying adaption to diverse environments at different locations within Europe the project design simulates the influence of climate change on berry cultivation. GoodBerry will build on novel molecular tools to apply cutting-edge genomic and metabolomics based approaches to deliver holistic solutions addressing the challenges of increasing productivity efficiency, crop resilience and food quality in the light of climate changes.

Project start: 01.03.2013
Project end: 31.12.2016
Sponsor: Federal Ministry of Food and Agriculture

Rubus stunt is considered the most important phytoplasmosis on raspberries and can cause yield losses of up to 100%. With the diagnostic methods available so far, latently infected but also symptomatic plants are not detected properly. In addition, potential vectors and possible transmission routes are unknown. The aim of the project is to develop a highly sensitive and rapid molecular on-site test system for the early diagnosis of this phytoplasmosis. In addition, findings on the species spectrum of potential vectors and further transmission routes are to be obtained, which will serve as a basis for the development of targeted and timely control measures. The development of a molecular method for the diagnosis of Rubus stunt will follow the establishment of an on-site sampling protocol based on TaqMan probes, LAMP assays and label-free detection. Investigations on the species spectrum and phenology of potential vectors, further transmission routes, the susceptibility of raspberry cultivars as well as on targeted control measures are to be carried out in a raspberry propagation farm or in yielding plants. Based on this, management strategies for the propagation and cultivation of raspberries will be developed. Finally, the methods developed for molecular phytoplasma diagnostics are to be validated under field conditions and transferred to other crops for the detection of phytoplasmas.

Project start: 01.05.2011
Project end: 31.10.2014
Sponsor: European Commission

Beside the traditional cultivation of raspberry in open field, they are now increasingly grown under rain protection or in high tunnels to extend the cropping period. The main used plastics are standard polyethylene foils to cover rainshelters and tunnels. However, different materials are available nowadays which vary in their transparency for UV radiation or have shading properties. Raspberry leaves and berries are rich in in vitamin C and polyphenols. They are synthesized at biotic or abiotic stress and their antioxidant action protect the plants against oxidative stress by free radicals. Moreover, these bioactive compounds play a crucial role in the prevention of a wide range of human diseases. The use of high tunnels alters the growing conditions for raspberries by changes of the microenvironment, mainly temperature. Photosynthesis is one of the most temperature-sensitive factors controlling plant growth. Beside photosynthesis, heat stress is negatively associated with a lot of physiological activities. However, less is known about changes of photosynthesis, carbohydrate synthesis and accumulation of nutritional ingredients in raspberry fruits grown under plastic tunnels. Therefore, the impact of different environments (light intensity and – quality, temperature and rel. humidity) on photosynthesis of raspberry plants and their carbohydrate and polyphenol compounds will be studied in a comparative trial between cultivating them in open field or in high tunnel with shading or different UV transparency properties.