Pollination and Fertilization Dynamics in Raspberry

Pollination and fertilization are critical determinants of fruit set and quality in raspberry. To optimize cross-breeding strategies and cultivation practices for raspberry, this study investigated key factors influencing pollination efficiency, including stigma receptivity and pollen tube growth dynamics. Results indicated that raspberry exhibited a wet stigma morphology with a solid-style structure containing a guiding tissue. Maximum stigma receptivity was observed at the petal opening stage. Pollen germination on the stigma initiated within 4 h post-pollination, with pollen tubes reaching the ovary base by 12 h, culminating in successful double fertilization. Embryo sac activity remained elevated throughout the first 48 h post-pollination, achieving an exceptional fruit set rate exceeding 80%.