Objective  Regularity and characteristics of as well as factors affecting the late-stage inflorescence of pear trees relating to fruit bearing of the plants were studied.

  Method  Occurrence time and location of late-stage flowers on pear trees as well as physiological and environmental factors affecting the inflorescence were systematically monitored in the field.

  Result  The late-stage flowers started to appear on a pear tree 10 days or more after regular inflorescence in spring and lasted till September. They showed up 70.27% of the time during the period when pears formed from regular flowers were rapidly expanding on a plant, 16.89% when the fruits were slowly enlarging, 7.93% when the fruits were rapidly enlarging, and 4.46% when the fruits were storing and accumulating nutrients. They were found mostly on tip of annual auxiliary shoots (94.64% of total), some on tip of mid-long shoots at 4.29%, and a few on tip of perennial adventitious buds at 1.07%. Compared with the regular flowers, the late comers were longer on the inflorescence axis with 3 or 4 small leaves on the base, bigger on the spacing between individual flowers, lengthier on the stalks, and smaller on the receptacle. They also started blooming from the center rather than the peripheral of a inflorescence. Of all, 43.23% of the fruit-setting from the late-stage flowers occurred in the rapid expanding period of regular fruits, 16.61% in the slow fruit enlarging period, 29.44% in the rapid fruit enlarging period, and 29.48% in time of nutrient storing and accumulating on Huanghua pear plants. The late-stage flowers found on the auxiliary shoots would generally develop and form fruits that ripened on the tree. Such result was observed on the pear plants with ample nutrient supply, of the varieties that showed a high rate of bud formation and long florescence period, and/or during the years encountering stresses such as serious diseases, pest infestation and/or climatic changes that affected fruit development.

  Conclusion  The late-stage flowers on a pear tree were largely found in the rapid expanding time of the regular fruits and on the tip of annual auxiliary shoots. They had longer inflorescence axis, wider spacing between flowers, lengthier stalks, and smaller receptacles than the regular flowers on a same plant. Their blooming sequence was opposite to the regular inflorescence. The late-stage flowers on the auxiliary shoots that bloomed early generally developed fully into fruits that matured into edible product for marketing. At time of yield decline due to diseases, the late fruit bearing compensated somewhat the loss. The delay could also inadvertently alter the fruit harvesting. Therefore, if late-stage inflorescence was desired, applying fertilization coupled with external stress to induce changes on the plant physiology could be a plausible approach.