Figure 3.
Defoliation accelerated flower bud development. A, Photographs of dormant flower buds from mock control trees (top) and sprouted flower buds in different states from defoliated trees (bottom) at 10 days after defoliation in 2019. B–E, Vertical sections of flower buds collected at 6 days (B, C) and 11 days (D, E) after defoliation from mock control trees and defoliated trees in 2018. Red arrowheads indicate the pistil primordia of buds after defoliation. White arrowheads indicate the center of flower primordia without the pistil primordia of buds in the mock control group. F–O, Scanning electron micrographs of fruit spur flower buds from mock control trees (F–J) and defoliated trees (K–O) at 0, 5, 10, 16, and 20 days after defoliation in 2019. The central floral primordium is labeled with a white dashed line, with magnified images of the petal primordia, stamen primordia, and pistil primordia (bottom). Scale bars, 5 mm (A) and 200 μm (B–E). pp, petal primordium; triangles, stamen primordium; and asterisks, pistil primordium.