IZN Junior group research program

Drought is known to inhibit and delay flowering by reducing spikelet fertility during inflorescence development through affecting the establishment of spikelet meristems. These events are a major cause of yield loss. Until now we fail to understand the molecular events, especially the cross-talks between growth hormones influencing number of spikelet meristem formation under drought, which will be a major focus of the research group.

A: To understand these mechanisms integrative genomics approaches will be used to explore natural genetic variation in barley by studying introgression line populations (with wild barley accessions as donors). We would like to elucidate the molecular physiological mechanisms of how partitioning of assimilates takes place during the establishment of spikelet meristem. Having understood these mechanisms we would like to reveal the hormonal cross talks and identify key regulatory networks promoting the establishment and growth of spikelet primordium under drought in drought-tolerant and drought sensitive lines. These networks could be used as potential targets for genetic manipulation through GMO and Non-GMO approaches to improve spikelet fertility and increase grain number under challenging environmental conditions.

B: In our second approach we would like to test whether the manipulation of spikelet architecture (results in a simultaneous increase in seed number and assimilatory ear organs) would be an added advantage for post-anthesis drought tolerance to promote seed filling and increased yield. Hence we would like to study the molecular physiological mechanisms of transgenic barley plants depicting branching phenotypes in spike architecture as well as to identify positive regulators influencing phenotype conversion from two rowed to six rowed phenotypes. Having understood these mechanisms we would like to assess whether increased photosynthetic capacity by the increased ear organs due to the change in spike architecture helps to better perform these transgenic and mutant barley plants for post-anthesis drought tolerance during the grain filling phase.

C: In our third approach, we will be making an attempt to establish correlation networks from the derived gene networks using throughput transcriptome, measured hormones, targeted metabolites from GMO material shown to confer drought tolerance. These correlation analysis will be performed to understand the developmental stage specific physiology influencing spike development, fertilization and grain filling under drought. All the data accumulated in this IZN-funded junior research group as well as from other ongoing projects (GABI-GRAIN, SEED-SET, PRO-DROUGHT) will be tailored to derive global relationships between hormones, transcripts, metabolites and phenotypes through statistical exploration using correlation approaches.

The junior research group is mainly funded by the Ministery of Culture of Saxony-Anhalt in the frame of the Interdisziplinäres Zentrum für Nutzpflanzenforschung (IZN). There is a strong connection to the Martin-Luther-University Halle-Wittenberg and Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben.