Seed endophytes: needless or indispensable during plant development? (Research)
Plant-bacteria interactions are complex and are subject of many studies because of their numerous applications. An important group of endophytes, bacteria that live in the internal tissues of the plant without causing harm, are seed endophytes. These bacteria are transmitted from generation to generation via seed and are already present in the embryo. Recent research suggests that seeds could serve as a vector for transmission of beneficial bacteria [1, 2]. However, little is known about the influence of seed endophytes on seed germination and plant development. Earlier research on Nicotiana tabacum has demonstrated that the number of seed endophytes and germination strength decrease with increasing seed age . First, it will be investigated whether differences in germination and germination capacity can be attributed to differences in seed endophyte population. For this, the germination of Arabidopsis thaliana will be subdivided in different phases  of which the duration will be compared for seeds of different age. Next, the seed endophytes of Arabidopsis thaliana, isolated from seeds of different age, will be characterized by checking the production of molecules important in seed germination. Based on this, some seed endophytes will be selected and labelled with green fluorescent protein (gfp)  in order to study the colonisation pattern in the root using confocal microscopy. In the last phase, the growth promoting properties of the selected seed endophytes will be studied in the model organism Arabidopsis thaliana. Root growth and morphological parameters will be compared between inoculated and non-inoculated plants. At last, proteins expressed in response to inoculation will be detected and identified.
Period of project
01 October 2009 - 30 September 2011