Share

The influence of fruit on the regulation of internal ethylene concentrations and sex expression in Cucurbita texana

Authors:

Krupnick, G.A.; Brown, K.M.; Stephenson, A.G.

Source:

International Journal of Plant Sciences, Volume 160, Issue 2, p.321-330 (1999)

Download Options:

Full Text:

Sorry, publisher does not permit download

My library:

openurl resolver

Abstract:

In many monoecious plant species, developing fruits inhibit pistillate flower production and promote staminate flower production. Ethylene is known to promote pistillate flower production in various wild and cultivated plants. The effect of fruit development on internal ethylene production and their combined effects on sex expression in field-grown C. texana was investigated in Pennsylvania, USA. Plant sex expression was compared for plants with and without fruits. Internal ethylene concentrations were determined within the hollow internodes of branches. Plants without fruits had more than twice as many pistillate flowers than plants with fruits. Ethylene concentration was the highest within internodes just below the tips of branches compared with more basal internodes (2-21 internodes from the tip) in both fruiting and fruitless treatments. Ethylene concentrations within branches with fruits were highest 18 days after pollination, just as fruits reached their maximum volume. Branches with 2 or more developing fruits had the lowest ethylene concentrations. Young developing fruits may send a signal that inhibits ethylene production, leading to the promotion of staminate flowers. When fruits are no longer strong resource sinks, ethylene concentrations increase and promote pistillate flower production