by koestoyo

University of Florida researchers publish award-winning findings on orange grove design to produce fruit under HLB

FORT PIERCE, Fla.— The American Society for Horticultural Science will honor University of Florida scientists for new guidelines citrus growers may apply to their operations. The researchers study ‘Valencia' orange production while trees are under the most serious citrus disease worldwide.

“The 7-year study broke new ground on data we provide to local citrus growers who remain in business despite huanglongbing, or HLB,” said Ronald D. Cave, Director of the University of Florida Institute of Food and Agricultural Science's Indian River Research and Education Center in Fort Pierce (UF/IFAS-IRREC).

A few of the findings citrus growers may employ immediately from the study are:

• High-density plantings produce more fruit—from 86% up to 300% more than trees not planted in high-density configurations under HLB.

• The study showed that advanced management practices that included high tree density, fertigation, and drip irrigation led to higher fruit yield.

• Additional research is needed to determine optimal fertilization rates for high-density sweet orange orchards under HLB-endemic conditions

The award-winning publication, “Sweet Orange Orchard Architecture Design, Fertilizer, and Irrigation Management Strategies under Huanglongbing-endemic Conditions in the Indian River Citrus District,” appears in the December 2020 issue science of the scientific journal HortScience. The paper describes the scientists' hypothesis, the entire research procedure, outcomes, and recommendations for further research.

Members of the American Society for Horticultural Science (ASHS) Fruit Publication Selection Committee wrote about the paper's significance. “Huanglongbing, also known as citrus greening, affects all citrus cultivars and causes serious tree decline. It is currently a major threat to the citrus industry. The results can influence the whole citrus industry to deal with HLB including orchard architecture design, fertilizer, and irrigation management strategies.”

Rhuanito “Johnny” Ferrarezi and his colleagues conducted experiments to determine the variables that promote healthy fresh fruit harvests with the presence of HLB. Ferrarezi, along with fellow professors Mark Ritenour and Alan Wright, will accept the “Outstanding Fruit Publication Award” for papers published in 2020 at the ASHS annual meeting awards ceremony in Denver, Colorado, Aug. 6. Ferrarezi is an Assistant Professor of Citrus Horticulture; Ritenour, Professor of Postharvest Technology; Wright, Professor of Soil and Water Science.

Others who contributed to the research and the award-winning publication are Arun D. Jani, a post-doctoral research assistant; Thomas James III, who manages citrus research groves; and Cristina Gil, an agricultural research assistant.

“We strive to keep citrus growers in business even though HLB is reducing the profitability of infected trees over time,” said Ferrarezi. “The point is to sustain younger trees for a number of harvests to produce the healthy, delicious fruit that made the Indian River District famous.”