基于非叶气孔研究非洲菊切花的失水凋萎机制与调控

非洲菊切花采后不带叶却极易发生失水凋萎，并直接影响观赏品质和商品价值。申请人前期研究发现非洲菊切花花萼、花瓣和茎等非叶部位均有气孔分布，并推测非叶气孔水分散失很可能是其采后失水凋萎的关键原因。但目前对切花非叶气孔研究报道极少，且对其在切花采后失水凋萎中的作用与调控机制尚不清楚。为此，本项目以非洲菊切花为试材，围绕离体（即各非叶部位及保卫细胞）和完整切花两条主线，采用形态结构观察、采后生理指标测定、保卫细胞转录组测序、关键转录因子功能分析等技术手段，系统研究该切花各非叶部位气孔的形态结构、行为特征和失水特性以及ABA、光、水分等气孔运动重要调控因子处理对非叶气孔开闭行为、切花失水凋萎和观赏品质的影响，藉此探明非叶气孔在该切花失水凋萎中作用与调控的结构基础及生理与分子机制，并为探寻一条“调控非叶气孔开放=>减少非叶气孔水分散失=>减轻切花失水凋萎”的新思路及提出相应的采后处理技术提供科学依据。

Cut gerbera flower, as the typical case that has no leaves, is very prone to water loss and rapid wilting, which directly disrupts their ornamental quanlity and commodity value. In our preliminary study, it was found that stomata were widely distributed on its non-leaf parts such as sepals, petals and scape in cut gerbera flower, and it is speculated that water loss through these stomata may be the key cause of its postharvest water loss and wilting. But so far there are few research reports on the non-leaf stomata in cut flowers, and little is known about their functions in water loss and its regulation mechanism. Hence, the present project, using cut gerbera flowers as the experimental materials, via in vitro (namely detached sepals, petals and isolated guard cells obtained by Laser Microdissection technology) and intact cut-flowers, based on the microscopic structure observations, postharvest physiological index measurements, transcriptomic sequencing of guard cells and functional analysis of key transcription factors, systematically studies the morphological structure, behavior characteristics and water loss performance of non-leaf stomata in different parts of cut gerbera flowers, and the effects of various postharvest treatments (designed from the key regulating factors of stomatal movement, including abscissic acid, light/dark and water stress, etc) on the stomatal opening and closing, and on water loss and ornamental appearance of cut flowers, aims at exploiting and understanding the structural basis and physiological and molecular mechanism of the non-leaf stoma function in water loss and wilting of cut gerbera flowers. The results from this project will also help to address a new approach to control the opening of the non-leaf stomata and then to reduce water loss through them, and ultimately to alleviate postharvest wilting of cut gerberas and even other cut flowers.