Biology subjects

von Korff Schmising, M.

Publications and source records attributed to von Korff Schmising, M..

2 recordsLinked to original sources

bioRxiv2020

FLOWERING LOCUS T4 (HvFT4) delays flowering and decreases floret fertility in barley

FLOWERING LOCUS T-like genes (FT-like) control the photoperiodic regulation of flowering in many angiosperm plants. The family of FT-like genes is characterised by extensive gene duplication and subsequent diversification of FT functions which occurred independently in modern angiosperm lineages. In barley, there are 12 known FT-like genes (HvFT) but the function of most of them remains uncharacterised. This study aimed to characterise the role of HvFT4 in flowering time control and development in barley. The overexpression of HvFT4 in the spring cultivar Golden Promise delayed flowering time under long-day conditions. Microscopic dissection of the shoot apical meristem (SAM) revealed that overexpression of HvFT4 specifically delayed spikelet initiation and reduced the number of spikelet primordia and grains per spike. Furthermore, ectopic overexpression of HvFT4 was associated with floret abortion and with the downregulation of the barley MADS-box genes VRN-H1, HvBM3 and HvBM8 which promote floral development. This suggests that HvFT4 functions as a repressor of reproductive development in barley. Unraveling the genetic basis of FT-like genes can contribute to the identification of novel breeding targets to modify reproductive development and thereby spike morphology and grain yield. HighlightWe identify the FLOWERING LOCUS T (FT)-like gene HvFT4 as a negative regulator of reproductive development, spikelet initiation, floret fertility and grain number in barley.

developmental biology↗

bioRxiv2020

Ppd-H1 integrates drought stress signals to control spike development and flowering time in barley

Drought impairs growth and spike development and is therefore a major cause of yield losses in the temperate cereals barley and wheat. Here, we show that the photoperiod response gene PHOTOPERIOD-H1 (Ppd-H1) interacts with drought stress signals to modulate spike development. We tested the effects of a continuous mild and a transient severe drought stress on developmental timing and spike development in spring barley cultivars with a natural mutation in ppd-H1 and derived introgression lines carrying the wild-type Ppd-H1 allele from wild barley. Mild drought reduced the spikelet number and delayed floral development in spring cultivars but not the introgression lines with a wild-type Ppd-H1 allele. Similarly, drought-triggered reductions in plant height, tiller and spike number were more pronounced in the parental lines compared to the introgression lines. Transient severe stress halted growth and floral development, upon rewatering introgression lines, but not the spring cultivars, accelerated development so that control and stressed plants flowered almost simultaneously. These genetic differences in development were correlated with a differential downregulation of the flowering promotors FLOWERING LOCUS T1 and the BARLEY MADS-box genes BM3 and BM8. Our findings, therefore, demonstrate that Ppd-H1 affects developmental plasticity in response to drought in barley. HighlightWe show that Ppd-H1 integrates photoperiod and drought stress signals via FLOWERING LOCUS T 1 (FT1) and the downstream MADS-box genes BM3 and BM8 to modulate reproductive development, and shoot and spike morphology in barley.

plant biology↗