Objective Contents, vitality, and optimal preservation conditions of male Actinidia arguta pollens at flowering stages were studied.

Method Average amounts and viability of the pollens in the flower buds of an A. arguta Liaonong 3-1 plant in 5, 4, 3, 2, 1 d before and 1d after flowering were compared. Prior to dehydration, the collected buds were either used as it with no pretreatment (CK), broken in half by hand one at a time, manually picked for anthers, or mechanically homogenized for 3 s, 2 s or 1 s (in the homogenizer) . Rates of flower bud dehydration and pollen viability retention at drying temperatures of 22 ℃, 25 ℃, and 28 ℃ were measured.

Result  As the flowers developing on the plants, amount of pollens rapidly increased to reach a maximum of 1.276% by weight 2 d before flowering. Anthers-picking drastically reduced the subsequent pollen production on a plant. A quadratic power function on pollen collection was observed. Homogenizing flower buds for 1 s helped release the pollens facilitating pollen drying in the dehydration and impurity reduction in the final pollen collection. In dehydration, higher temperature hastened the process, and the evaporation slowed down gradually after the relative dry weight of the buds fell below 23%. At 28 ℃, the relative dry weight of the flower buds could be brought to 22.98% in 13 h with no significant difference on pollen vitality from what was achieved by drying at 22 ℃ or 25 ℃.

Conclusion Male A. arguta flower buds could be collected 2 d before flowering to be homogenized for 1s and dried at 28 ℃ for 13 h to obtain large quantities of highly vital, fine powder pollens.