Peach (Prunus persica) is a fruit tree widely cultivated in temperate regions of the world, with ornamental and edible properties. Male sterility of peach is an important agronomic trait for hybrid vigor utilization, but its mechanism is yet to be fully uncovered. 

Supervised by Prof. HAN Yuepeng from Wuhan Botanical Garden, CAI Yaming combined cytology, physiology and molecular approach to investigate the mechanism of male sterility in ‘Jinxiang’ ('JX’), a popular yellow flesh peach cultivar in China.   

This research found that abnormal development of tapetum and microspores of ‘JX’ occurred at the mononuclear stage. The tapetum cells were swollen and intensely vacuolated and their degradation was obviously delayed. Meanwhile, few cytoplasmic inclusions were observed in microspores, which were compressed into belts and then disappeared in the anther cavity.   

Moreover, reactive oxygen species (ROS) homeostasis was disrupted, with abnormal increase in ROS content and altered ROS scavenging system, which might hinder the development of tapetum and pollen grains, leading to male sterility in peach.   

This research further reveals that the male sterility appears to be cytoplasmic in peach, which could be due to sequence variation in the mitochondrial genome. This research will be useful for further investigation of mechanisms underlying male sterility in peach. 

Results were supported by funds received from the National Key Research and Development Program, the National Natural Science Foundation of China, and the China Agriculture Research System. It has been published in Frontiers in Plant Science entitled “Potential Association of Reactive Oxygen Species with Male Sterility in Peach”. 

Comparison of anther morphology between the fertile cultivar, ‘Zaohong’ ('ZH’) and the male sterile cultivar, 'Jinxiang’ ('JX’) using SEM (Image by CAI Yaming)