Abstract: Given the frequent occurrence of extreme weather during the mango flowering period due to global climate change, studying the tolerance of mango pollen at different temperatures is of great significance for the introduction, breeding, flowering management, and selection of new mango varieties. This article takes 'Renong 1', 'Dashehari', 'Apple Mango' and 'Jinhuang' as the research objects，and estimated the maximum pollen germination rate (Q), pollen tube length, and the basic temperatures (Tmin, Topt, and Tmax) using quadratic equations and modified bilinear models under conditions of 14−36℃. The cumulative stress response index (CSRI) was used to  study the impact of temperature on pollen germination characteristics and to determine the differences among mango pollen types/genotypes. The results showed that temperature and duration significantly affected pollen vitality. Both pollen germination rate and pollen tube length increased with temperature, reaching a maximum value at 28℃(35%, 53.2μm), and then decreased with further temperature increase. Significant differences were observed in pollen germination rates and pollen tube lengths among different varieties. Specifically, 'Renong 1' had the widest temperature range for pollen germination (22−32℃) and pollen tube growth (22−34℃), while 'Apple Mango' had the narrowest pollen germination temperature range (22−30℃). 'Dashehari' exhibited the narrowest pollen tube temperature range (24−32℃). The inhibitory effect of low temperature on pollen tube growth was greater than that of high temperature on pollen germination. 'Renong 1' exhibited the strongest resistance to both low and high temperature stresses, while 'Apple Mango' was the most sensitive.  

Key words: Mango, Pollen germination, Temperature stress, Cumulative stress response index