The effect of the limitation of insect pollination period on the fruit set and yield of temperate-zone fruit tree species

Abstract

The duration of effective bee pollination period was limited by caging flowering branches for shorter or longer time in blooming fruit trees in a number of experiments during the past decades. In the case of self-sterile fruit species and cultivars (apples, pears, quinces, some plums, some sour cherries) even partial limitation of the effective duration of bee pollination period significantly reduced the fruit set and the yield. In the case of self-fertile apricots the effect of the total and also the influence of partial limitation of bee pollination period was the same as in the case of the mentioned self-sterile fruits. On the other hand, in the case of another self-fertile fruits (some plums, some sour cherries), the effect of partial limitation of bee pollination period was usually small, but complete (or incomplete but strong) limitation of be pollination usually resulted in a strong reduction of yield. This means that not only self-sterile but also self-fertile fruits clearly depend on insect (bee) pollination. This is because pollen dehiscence of anthers and the receptive period of stigmas do not overlap in time within the individual flowers. Stigmas in self-fertile trees, therefore, need pollen carried by bees from another flowers of the same tree (or compatible pollen from another trees). Accordingly, additional bee pollination (moving bee colonies to the orchards in flower) is needed to all kinds of temperate-zone fruit tree species when bee visitation of plantations is not abundant enough for some reasons.

Pollination biology of fruit-bearing hedgerow plants and the role of flower-visiting insects in fruit-set

“…If fruit-set is reduced in the absence of insects and pollen limitation is occurring it might be predicted that reducing the time of exposure of flowers to insects would have an effect on fruit-set. For example, Benedek et al (1994Benedek et al ( , 2000Benedek et al ( , 2006 found that even partial exclusion of pollinators resulted in a decrease in fruit yield in both self-incompatible and self-fertile cultivars of orchard trees.…”

Incompatible pollen tubes in the quince style and their impact on fertilization success

“…Therefore, appropriate pollinisers must be provided, which will enable abundant fruit set and high yields (Dicenta et al, 2002). It is considered that for high yields in quince, more than 20% of the fruit must be set (Szabó et al, 1999;Benedek et al, 2000).…”

Fruit set and yield of pear cultivars as affected by reduced bee pollination period

“…On the other hand, at self-fertile fruits, the effect of partial limitation of bee pollination period is usually small, but complete (or incomplete but strong) limitation usually results in a strong reduction of yield (Benedek & Nyéki, 1995, 1996a. This means that not only self-sterile but also self-fertile fruits clearly depend on insect (bee) pollination (Benedek et al, 2000a).…”

“…Consequently, pear can produce acceptable yield even under adverse conditions. In spite of this fact most studies on the effect of reduced bee pollination to the fruit set and the yield has been made with apple (Benedek et al, 1989, Benedek & Nyéki 1995, 1996a, 1996b, 1997) and very little information was available to pear in this respect (Benedek & Nyéki 1996a, Benedek et al 2000a. It was established by Nyéki et al (1998) that the inclination or capacity to parthenocarpy can be more or less different among cultivars but it is also largely dependent on site and season.…”