Abstract
The Mediterranean basin is particularly sensitive to adverse outcomes of climate change and especially the incidence of high temperatures. Adverse environmental conditions will affect crop performance and productivity and will be particularly severe on woody crops, including citrus, which is the proof of concept chosen in this project to study the impact of temperature stress on reproduction and plant physiology. In particular, reproduction is affected by climate change due to morphological, physiological and molecular alterations in male and female organs. Temperature changes also affect pollen-pistil interaction and particularly the self-incompatibility reaction. In citrus (especially in mandarins) the absence of fertilization usually leads to seedless parthenocarpic fruits, which is a much-prized character. However, temperature stress is known to cause the breakdown of self-incompatibility in citrus, resulting in seedy fruit. This project aims to a better understanding of reproduction in citrus (especially in mandarins and mandarin-like varieties such as clementine) so as to evaluate the damaging effects of non-optimal temperature conditions that can occur during the reproduction cycle, from floral induction to fruit set. The project will be focussed on the effect of temperature stress in incompatibility reaction, which will be assessed in selected mandarin varieties [self-compatible (SC) and self-incompatible (SI) genotypes] exposed to different temperature regimes in crucial steps of the fruitification cycle. An integrated cytological, molecular and genetic approach will be applied to decipher the effects of temperature stress. In particular, histo-molecular analysis in planta will be performed to assess the effect of temperature stress on reproductive organs development and on fertilization process. Pollen viability and behavior will be analyzed in in vitro tests while the analysis of female gametophyte will provide information on the damage caused to male-female crosstalk. Transcriptomic and epigenomic studies during male and female gametophyte development under temperature stress will provide specific insight into the pathways involved in the response of plants to temperature stress during reproduction. Results will provide insight into the pollen-pistil interaction in mandarin varieties of selected genotypes (SC and SI) under critical environmental conditions. Comprehensive understanding of how temperature variation alters the reproductive process will unravel the physiological, molecular, and genetic basis of sterility in citrus and help define the temperature conditions causing seedy fruit production and high depreciation of their commercial value. Furthermore, the availability of reference genomes of clementine (C. clementina Hort. ex Tan.) and mandarin (C. reticulata Blanco) will allow the development of biotechnological tools useful in the selection process of new varieties with better performances under temperature stress.
Project details
Unibo Team Leader: Stefano Del Duca
Unibo involved Department/s:
Dipartimento di Scienze Biologiche, Geologiche e Ambientali
Coordinator:
Università di Siena(Italy)
Total Unibo Contribution: Euro (EUR) 66.891,00
Project Duration in months: 24
Start Date:
12/10/2023
End Date:
28/02/2026
