Acta Horticulturae Sinica ›› 2021, Vol. 48 ›› Issue (8): 1457-1469.doi: 10.16420/j.issn.0513-353x.2020-0538

• Research Papers • Previous Articles     Next Articles

Changes of Fruit Abscission and Carbohydrate,ABA and Related Genes Expression in the Pericarp and Fruit Abscission Zone of Longan Under Starvation Stress

YANG Weihai1, ZENG Lizhen1, XIAO Qiusheng1, SHI Shengyou2,*()   

  1. 1College of Life Science and Resources and Environment,Yichun University,Yichun,Jiangxi 336000,China
    2South Subtropical Crops Research Institute,Chinese Academy of Tropical Agricultural Sciences,Zhanjiang,Guangdong 524091,China
  • Received:2021-01-17 Revised:2021-04-06 Online:2021-08-25 Published:2021-09-06
  • Contact: SHI Shengyou


In order to explore the regulation mechanism of longan fruit abscission induced by “starvation stress”,a treatment of girdling and defoliation was made on the bearing shoots of longan cultivar‘Chuliang’at the early stage of fruit development,simulating starvation stress induced by interrupting carbon supply to fruit cluster,and the levels of carbohydrate,abscisic acid(ABA)and related genes expression in the pericarp and the pedicel abscission zone were investigated at 0,1,3,5 and 6 d after treatment,respectively. The results showed that a severe fruit drop occurred at 5-6 d after starvation stress treatment,the contents of total soluble sugar and its components(glucose,fructose,sucrose)in pericarp were significantly decreased,and the reduction was relatively large during 3 d after treatment,with the decreases of sucrose and glucose significantly larger than fructose. Meanwhile,the similar changes in the levels of total soluble sugar and sucrose also occurred in abscission zone. After being treated,ABA content did not change obviously in pericarp,while increased significantly in abscission zone. Starvation stress generally decreased the expression of genes related to carbohydrate and ABA in the pericarp and abscission zone,the expressions of genes involved in sugar metabolism(NI,SS1,SPS1),sugar signaling(HXK2,TPS1,SnRK2)and ABA metabolism(AAO3,NCED,BG)were significantly decreased during the early stage of fruit shedding,whereas NI,SS1,HXK2,SnRK2,AAO3 and NCED genes were expressed with up-regulation in the period of severe fruit drop,resulting in the sharply decreased sucrose,occurring of sugar signal and ABA accumulation. These results suggested that a crosstalk between sugar and ABA may be related to longan fruitlet abscission induced by carbohydrate starvation.

Key words: longan, girdling and defoliation, starvation stress, carbohydrate, abscisic acid, pericarp, abscission zone, fruit abscission

CLC Number: