Biology subjects

Manes, Y.

Publications and source records attributed to Manes, Y..

2 recordsLinked to original sources

bioRxiv2024

Stigma longevity is not a major limiting factor in hybrid wheat seed production

Hybrids offer a promising approach to improve crop performance because the progeny are often superior to their parent lines and they outyield inbred varieties. A major challenge in producing hybrid progeny in wheat, however, lies in the low outcrossing rates of the maternal parent. This is often attributed to suboptimal synchronisation of male and female flowering as delayed pollination can result in reproductive failure due to female stigma deterioration. To test this accepted dogma, we examined the seed set capacity of six male sterile (MS) cultivars, each varying in the onset of stigma deterioration. To mimic a hybrid seed production scenario, MS cultivars were grown during two consecutive field seasons, and open pollination was allowed up to 15 days after flowering of the female parent using a blend of seven male fertile cultivars with varying flowering times. Detailed analysis of the temporal and spatial distribution of hybrid seed set along the spike across the six MS cultivars showed that grain production remained remarkably stable during the pollination window tested. These findings suggest sustained receptivity of stigma to pollen across all tested MS cultivars throughout the entire time course. We therefore conclude that stigma longevity does not represent a limiting factor in hybrid wheat seed production, and that breeding efforts should prioritise the study of other female traits, such as enhanced access to airborne pollen.

plant biology↗

bioRxiv2022

A scalable phenotyping approach for female floral organ development and senescence in the absence of pollination in wheat

In the absence of pollination, female reproductive organs senesce leading to an irrevocable loss in the reproductive potential of the flower and directly affecting seed set. In self-pollinating crops like wheat (Triticum aestivum), the post-anthesis viability of the unpollinated carpel has been overlooked, despite its importance for hybrid seed production systems. To advance our knowledge of carpel development in the absence of pollination, we created a relatively high-throughput phenotyping approach to quantify stigma and ovary morphology. We demonstrate the suitability of the approach, which is based on light microscopy imaging and machine learning, for the detailed study of floral organ traits in field grown plants using both fresh and fixed samples. We show that the unpollinated carpel undergoes a well-defined initial growth phase, followed by a peak phase (in which stigma area reaches its maximum and the radial expansion of the ovary slows), and a final deterioration phase. These developmental dynamics were largely consistent across years and could be used to classify male sterile cultivars, however the absolute duration of each phase varied across years. This phenotyping approach provides a new tool for examining carpel morphology and development which we hope will help advance research into this field and increase our mechanistic understanding of female fertility in wheat.

plant biology↗