CSIRO Identifies Causes of Premature Avocado Fruit Drop

Australia's national science agency, the CSIRO, has published findings from a five-year study aimed at identifying the causes of premature fruit drop in avocado crops, an issue that significantly impacts agricultural yields across the country.

The research, supported by Hort Innovation and published in the Journal of Experimental Botany, investigated immature fruit abscission—a physiological process in which trees shed developing fruitlets prior to harvest. The study determined that early fruit drop is triggered by hormonal changes within the seed coat of the fruit in response to reduced carbohydrate availability.

According to CSIRO project lead Dr. Harley Smith, the initial phase of the research centered on understanding the developmental and physiological factors behind the shed. Smith noted that immature fruit abscission contributes directly to annual yield fluctuations, creating challenges for market development.

Following these findings, researchers have entered a second phase of the project, focusing on identifying plant growth regulators that could potentially be applied to reduce immature fruit loss.

Avocados Australia CEO John Tyas stated that growers can experience losses of up to 80 percent of their annual crops due to early fruit drop. Tyas noted that the findings and subsequent management strategies are particularly critical for producers in Queensland and Western Australia, where early fruit loss heavily reduces total harvest numbers.

According to the CSIRO, the Australian avocado industry generates more than 130,000 tonnes of fruit annually and contributes approximately $800 million to the national economy.

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