Plan Greasy Spot and Melanose Management

Tacy CalliesDiseases, Tip of the Week

By Megan Dewdney Greasy spot and melanose are two fungal diseases that have long needed the attention of Florida citrus growers. While they are more of a concern for fresh fruit growers, trees for processing can be damaged, too. In terms of management priorities, greasy spot is the greater concern since it reduces tree photosynthetic capacity and causes defoliation. Melanose …

pests

Traditional and Alternative Leafminer Control Methods

Tacy CalliesPests

By Lukasz Stelinski The citrus leafminer (CLM) remains a major pest of citrus throughout Florida. The adults are small, white/silver-colored moths about half the size of a typical mosquito (Figure 1). Adults are difficult to spot due to their small size and because they are active only in the evening (dusk) and early pre-dawn hours. CLM adults can be monitored …

nutrition

Peptide, CRAFT Research Funded

Ernie NeffResearch

A company that recently obtained a patent for a natural peptide solution to treat HLB has received Citrus Research and Development Foundation (CRDF) funding to see if the product has efficacy for other citrus diseases. CRDF will fund the company, Elemental Enzymes, for about $61,200, said CRDF Chief Operating Officer Rick Dantzler. Elemental Enzymes proposes to do research “to see …

Sequencing Brings HLB Resistance Closer

Ernie NeffBreeding, Research

University of Florida (UF) scientists achieved a major milestone in their quest to develop an HLB-resistant tree by sequencing the genome of a fruit plant that’s a close cousin to citrus trees. HLB is also known as greening disease. UF Institute of Food and Agricultural Sciences researchers sequenced the genome from trifoliate orange, in collaboration with scientists from the University …

Black Spot and Production Guide Updates

Ernie NeffDiseases

Megan Dewdney recently provided information about positive results from fungicide trials for citrus black spot, as well changes to the new Citrus Production Guide. Dewdney is a plant pathologist with the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), working at the Citrus Research and Education Center. Dewdney conducted the fungicide trials for black spot in a 20-year-old …

Phytophthora Root Rot Management

Tacy CalliesDiseases, Tip of the Week

By Evan G. Johnson As September winds down, the fall root flush is starting and will continue through November/December. This is the largest root flush of the year that stores carbohydrate reserves for next spring. Coming out of the rainy season, phytophthora has had the chance to build up plenty of inoculum, especially in groves with a history of root …

Rootstock Effects on Valencia and Hamlin in Large-Scale Commercial Plantings

Tacy CalliesResearch, Rootstocks

By Ute Albrecht, Sudip Kunwar and Jude Grosser Prior to 1865, the only rootstocks used in Florida were sour orange and sweet orange. Use of grafted trees instead of seedling trees became necessary because of the devastating effects of phytophthora on sweet orange. Sour orange was widely used as a rootstock because of its resistance to phytophthora and other positive …

Summer Tree Care Practices to Improve Fruit Quality and Yield

Tacy CalliesCitrus, Production

By Fernando Alferez and Tripti Vashisth As summer approaches and citrus trees bear developing fruit, growers can engage in several practices to improve fruit quality and yield. As temperatures rise and daylength increases, conditions are conducive for enhanced photosynthesis and accumulation of soluble sugars in the fruit. It is important to note that, in general, the temperature is negatively correlated …

Algal Spot: A Re-emerging Disease

Tacy CalliesDiseases

By Megan M. Dewdney Algal spot has not been seen frequently for many years, but in the last few years I have been getting more questions about identification and management. The disease is caused by a green alga, Cephaleuros virescens. The alga is not considered a parasite, as it grows superficially, but it does cause damage to trees if left …

Fungal Foliar Disease Concerns for 2019

Tacy CalliesDiseases

By Megan Dewdney The Florida citrus-growing seasons of 2017 and 2018 were quiet in terms of fungal foliar disease outbreaks. Small pockets of severe disease occurred sporadically, but there were no widespread reports of diseases like postbloom fruit drop, much to the relief of the industry. Greasy spot has flared up in a few locations on cultivars like Valencia, and …

HLB

Burns on HLB, Mechanical Harvesting

Ernie NeffHLB Management

Jackie Burns, who retired in January as dean for research at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS), discusses HLB, mechanical harvesting and other citrus issues on which she worked. Burns was a long-time scientist at the Citrus Research and Education Center and later director of the center before becoming dean for research. Burns said going …

PFD

Brown Rot Basics

Ernie NeffDiseases

Plant pathologist Megan Dewdney with the University of Florida Institute of Food and Agricultural Sciences discussed the basics of brown rot and its control at a recent disease seminar in Immokalee. Approximately 60 growers and others attended the seminar held at the Southwest Florida Research and Education Center. Brown rot is especially prevalent in early-season citrus varieties. “It’s particularly problematic …

research

Nutrition and pH Management for HLB

Ernie NeffHLB Management, Nutrition

At Citrus Expo, University of Florida soil scientist Kelly Morgan said nutrient uptake by HLB-infected trees can be improved by applying the proper amount of nutrition and managing pH. “Those two things go hand-in-hand,” he said. “As you reduce soil pH below 7, you increase the uptake of most nutrients. So we need to reduce our pH. Our pH has …

HLB, Replanting

What to Ask When Deciding What to Plant

Tacy CalliesRootstocks, Scions, Varieties

By Nate Jameson The decision-making process for choosing a scion/rootstock combination involves multiple factors. The process starts by answering the following questions: Question 1: New planting or resetting? If the block is being reset, is still profitable and will stay in production for several years, then I suggest the grower stay with the existing combination currently planted. If the block …

Field Testing of New HLB-Tolerant Scions and Rootstocks

Tacy CalliesResearch, Rootstocks, Scions

By Rhuanito S. Ferrarezi, Jude W. Grosser, Fred G. Gmitter, Ed Stover and Kim Bowman Citrus is Florida’s most important agricultural commodity. The state produces citrus for different markets: round oranges for juice; navels, mandarins, grapefruit and lemons for the fresh-fruit industry; and lemons for extracting peel oil for processing. Huanglongbing (HLB) disease affects all citrus varieties. Since the discovery …

citrus rootstock

Annual Meeting of the Florida State Horticultural Society

Daniel CooperIndustry News Release

The Florida State Horticultural Society (FSHS) announces that it will hold its 131st annual meeting on June 10 through June 12, 2018, at the Renaissance Fort Lauderdale Cruise Port Hotel located at 1617 SE 17th Street in Fort Lauderdale, Florida. With over 100 technical presentations and special sessions with invited speakers, there will also be a welcome reception, Extension luncheon, …

Jude Grosser: Giving Growers Better Options

Tacy CalliesBreeding

By Tacy Callies Some people start young adulthood by following in their parents’ footsteps. Jude Grosser began by following the path of his oldest brother, Tim, instead. Both went to Thomas More College and majored in biology. After that, their education and careers took different turns. Grosser thought he would work in wildlife or fisheries, but then had an opportunity …

pests

Robots May Soon Detect Grove Pests and Diseases

Ernie NeffDiseases, Pests, Technology

It may not be long before a grower sips coffee and works on the computer while a robot roams the grove checking for HLB-spreading psyllids and other pests and diseases. That’s thanks to machine vision software. University of Florida Institute of Food and Agricultural Sciences scientist Arnold Schumann tells about research he has been conducting. Schumann says researchers have developed …

forecast

Jonathan Brown Discusses Crop Forecast, Irma Damage

Ernie NeffForecast, hurricane

Citrus grower Jonathan Brown of Bethel Farms in Arcadia reacts to the Oct. 12 initial U.S. Department of Agriculture citrus crop forecast of 54 million boxes of Florida oranges. He also discusses damage from Hurricane Irma. “I was a little bit impressed that it (the forecast) came out where it did,” Brown says. “I was kind of expecting it to …