Temporal changes of disodium fluorescein transport in hazelnut during fruit development stage

Abstract

Corylus heterophylla Fisch typically produces high ratio of blank nut in Northeast China. Structure changes of female flower cluster and fruit were observed and patterns of disodium fluorescein transport into ovule and funiculus from fruit stalks were studied in the year of 2010–2012. The results indicated that early ovary and ovule of hazelnut were visible on about 20 and 45 days after blooming respectively, and the sizes of two ovules within an ovary were equal prior to 55 days after blooming, then the differences in ovule size became obviously along with development of the fruit. Ovules within blank fruit had little changes in size and maintained 2.0–4.0mm in length until harvest. However, the ovary size of blank was much closed to that of filled one during the whole fruit development stage. For filled nut, disodium fluorescein transport obstacle occurred at junction point of ovules and funiculus and led to the abortion of one ovule from 60 to 90 days after blooming, while bright fluoresce could be observed in funiculus until near harvest. For the blank fruit, fluorescein transport obstacle happened at junction point of ovules and funiculus first on 55 day after blooming, then the funiculus failed to execute the transport function from 60 to 90 days after blooming. In conclusion, transport obstacle occurred at junction point of ovules and funiculus first, and then happened in funiculus, and these phenomena were closely related with blank fruit formation in C. heterophylla Fisch.