Wild Blueberry Fruit Drop: A Consequence of Seed Set?

Abstract

<jats:p>Wild blueberry is a native plant managed as a crop in northeastern North America. Fruit drop in wild blueberry, Vaccinium angustifolium Aiton, was studied over 6 years (1996–1999, 2008 and 2011). Three hypotheses were tested regarding fruit drop mechanisms from plants (clones) sampled in the field: (1) proportional fruit drop; (2) constant or uniform fruit drop; and (3) pollen or resource limitation. In addition, the temporal rate of fruit drop was measured between the end of pollination (petal fall) and fruit maturity just prior to harvest (2008 and 2011). The dynamics of fruit drop were different in the two years. The role of pollination intensity in fruit drop was also assessed. Evidence for both proportional fruit drop and resource limitation at the clone level was found but only proportional drop at the field level. Low levels of seed set are associated with fruit drop. In a four-year study (1996–1999), fruit drop ranged from 23.3 to 49.4% of the total set fruit. Partitioning the variance in fruit drop between years, fields and clones (plant genotypes) showed that the highest variation is between stems within clones (37.4%) and clones (plant genotype) within fields (35.4%), followed by between fields (19.8%) and between years (7.4%).</jats:p>

Creation and Use of Highly Adaptive Productive and Technological Red Currant Genotypes to Improve the Assortment and Introduction into Different Ecological and Geographical Zones

“…The nature of the fall of berries seemed to be quite dynamic and could continue both during the entire growing season (2014) and a short period (2013, 2015). A similar pattern was observed in blueberry species [ 44 ]. The search for reports on the patterns and causes of ovary fall in other berry crops turned out to be futile.…”

Analysis of Pollination Services Provided by Wild and Managed Bees (Apoidea) in Wild Blueberry (Vaccinium angustifolium Aiton) Production in Maine, USA, with a Literature Review

“…The last visit occurred in late June for a final count of developing fruit. The proportion of fruit at the final count that developed from the initial flowers is a measure of late fruit set, after some of the premature fruit drop has occurred [32]. Late fruit set is not necessarily a measure of harvestable fruit as harvest typically occurs 3-6 weeks later, a time period during which environmental conditions can further reduce fruit number.…”

“…Measured by Asare et al [18], a 1% increase in fruit set will result in a 44.1 kg/ha increase in yield, and 60% of the variance in yield can be explained by fruit set and production practices. Increased levels of pollination also result in increased numbers of fertile seeds per berry, increased berry size and weight, and reduced premature fruit drop [4,32,44,55,70,107].…”

The Ecology of Autogamy in Wild Blueberry (Vaccinium angustifolium Aiton): Does the Early Clone Get the Bee?

“…Ten to fourteen d after bloom (early-mid-June), clones in both pollination treatments and bloom phenology classes were visited, and marked stems in both the open-pollinated and self-pollination treatments were located. The period between the end of bloom and estimation of fruit set allowed for many of the inadequately or non-pollinated flowers to drop [46]. green fruit were counted on terminal flower clusters and proportion fruit set was estimated by dividing the number of fruits by the number of flowers recorded in the terminal cluster (see [7] for more detail).…”