There are all kinds of pollinators in an avocado orchard, not just honeybees. In fact, there is a whole range of native bees that also pollinate the trees. There are nearly 1,600 native bee species in California, and over 30 have been identified in avocado orchards in Ventura County alone .

Another pollinator group is comprised of the Diptera order – flies. This order includes hoverflies and houseflies. Flies can be better at cross-pollinating avocado than honeybees because they move randomly through an orchard between different cultivars, visiting male and female flowers. The effectiveness of flies as pollinators varies between species, but there can often be more than 20 types in an orchard. This means it is likely that some good pollinators will be present, and that pollination can occur whenever the female flowers are open.

In the aforementioned Ventura avocado study, hoverflies are the most common flower visitor.

Housefly

Hoverfly

Terrestrial laser scanning data show that trees move their branches in a diurnal pattern, settling down for the night – as if falling asleep. So far, however, researchers have been uncertain as to why this happens.

A new study utilising time-series of terrestrial laser scanning measurements shows that changes in the water status of leaves and branches causes branches to move downward at night, up to 20 cm depending on the tree species. Leaves and branches replenish their water storage during the night, increasing their weight and causing them to droop down. Terrestrial laser scanning is a remote sensing technique that can produce a 3D representation of the surroundings with millimetre accuracy. With repeated measurements, it is possible to study small structural changes in the environment, such as the movement of branches.

“By monitoring the movement of tree branches, we can gain insight into how water moves inside the tree. Climate change reduces the availability of water and increases drought stress, so it is important to understand the movement of water in trees in order to understand changes in forest health,” Postdoctoral Researcher and the lead author of the article Samuli Junttila from the University of Eastern Finland says.

In the laboratory, the researchers found that tree branch position followed changes in tree water status also over a longer time period. These findings also have practical applications. For example, laser scanning could be used to monitor plant water status in a greenhouse to automate watering regimes and save valuable resources.

The study was conducted at the University of Eastern Finland in collaboration with the Finnish Geospatial Research Institute and the University of Helsinki. The study was conducted within the UNITE Flagship Programme funded by the Academy of Finland.

https://www.mdpi.com/1999-4907/13/5/728

 AGENDA

Aliasghar Montazar, our Irrigation Advisor in Imperial and San Diego Counties has a Specialty Crops grant from CDFA to evaluate avocado water use.  The trials have been set up in San Diego, but in the future may be able to expand the trials to other parts of the State.  He is hoping growers could fill out this survey on current water use in avocado orchards.  Try it, you might be reviewing what is currently being done, and learn something in the process.

Avocado Irrigation Management Survey

Thanks