By Davie Kadyampakeni Nutrients are needed for optimal citrus tree growth, fruit yields and juice quality. Any nutrient deficiencies could result in low yields and decreased revenue. Make sure citrus trees receive adequate macronutrients and micronutrients at all times. Macronutrients are those nutrients needed in large quantities to influence yield, growth and fruit quality. Macronutrients are further divided into two …
Wildflowers May Benefit Citrus Groves
By Xavier Martini Planting wildflowers in and around fields is known to provide food resources and habitats for beneficial arthropods like pollinators and predators of pests. In two locations (Lake Alfred and Monticello), University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers tested whether planting native Florida wildflowers next to citrus grove windbreaks could improve natural pest control …
Protecting Citrus Trees From Heat Stress
By Anirban Guha Heat stress could take a toll on citrus tree health and fruit yield. In Florida, the hot season lasts more than four months. Long, hot, oppressive summer days can heat up leaves and fruit and make the trees extra thirsty. Also, high soil evaporation, irregular rainfall and poor soil water-holding capacity can often lead to summer drought …
Reduce HLB Pressure and Enhance Growth With Kaolin
By Christopher Vincent Kaolin particle film is a non-toxic tool to reduce psyllids and increase tree growth. Particle films are nothing more than a suspension of solid particles that make a “film” on the leaves after they dry. They work mostly by reflecting light. Kaolin is the most common type of particle film because the clay is mined directly and …
Selecting the Right Leaves for Sampling
By Jamie D. Burrow and Tripti Vashisth With the increased cost and limited availability of fertilizer, purchasing decisions are more important now than ever. Collecting the right leaves for sampling is the first step to making fertilizer decisions. Leaf samples should consist of 100 leaves that are 4- to 6-month-old spring flush leaves taken from nonfruiting branches. WHY LEAVES FROM …
Releasing Rootstocks: Balancing Responsibility With Urgency
By Bill Castle, Fred Gmitter and Jude Grosser The rootstock development cycle, from creation to eight years in the field to release, is presently about 10 to 15 years. However, if multiple trials are involved, then the time required is increased. The criteria used to advance new selections through the system are commercially based. Rootstocks for juice fruit are assessed …
Changes in Pesticide Residue Tolerances on Citrus Destined for Korea
By Mark A. Ritenour The U.S. and other countries set maximum residue limits (MRLs) on fresh produce for various chemicals, including pesticides that might be used preharvest or postharvest. These materials must be labeled for use on the crop of interest and used only according to label instructions. While it is unlikely for U.S. MRLs to be exceeded when label …
Hurricane Season Is Here. Are You Prepared?
By Amir Rezazadeh Every year, hurricanes and tropical storms can occur in Florida from June 1 to Nov. 30. Hurricanes and tropical storms damage citrus trees by blowing fruit off trees or from flooding due to too much rain or high tides. Also, high tides due to wind may cause rising water levels and saltwater flooding. The best practice for …
Use Physical Barriers for Root Health
By Larry Duncan Citrus trees in Florida soils infested with diaprepes root weevil (Diaprepes abbreviatus) or sting nematode (Belonolaimus longicaudatus) frequently contend with devastating damage to their root systems. This is made even worse by root loss due to huanglongbing (HLB) disease. Where soil conditions are conducive to the insect or nematode, it is very difficult to prevent major economic …
Keep CTV Under Control
By Amit Levy Citrus tristeza virus (CTV) infects the citrus phloem. CTV infects almost all citrus varieties, but it causes different disease symptoms depending on the virus isolate, the citrus variety and scion-rootstock combination. Florida has three dominant strains of CTV: T36, a decline-causing strain T30, which normally does not cause severe disease VT, a stem-pitting causing strain CTV is …
Now Is the Time to Start Scouting for Rust Mites
By Xavier Martini Rust mites are recurrent pests in Florida that pose problems mostly in fresh citrus production. While severe infestations can lead to fruit drop, leaf injury and abscission, rust mites cause aesthetic damage in the form of sharkskin or bronzing on the skin of fresh fruit (Figure 1A). Fresh fruit requires clean and undamaged skin, and any abrasions …
Preparing to Plant Cover Crops
By Sarah Strauss If you’ve been exploring methods to improve your soil health, chances are you’ve come across the use of cover crops. Even though we call them “crops,” these plants are not harvested and are only planted to improve soil health. The benefits of cover crops to soil health include increasing soil organic matter and microbial diversity and activity …
Consistency Is Key in Rootstock Field Trials
By Bill Castle Today, at least three things seem to be true about Florida citrus rootstock field trials: There is an unprecedented number of them underway or soon to be planted. The sponsors are many, including the University of Florida, U.S. Department of Agriculture, Citrus Research and Development Foundation, Citrus Research and Field Trial Foundation and the Multi-Agency Coordination Group. …
Managing Weeds in Row Middles
By Ramdas Kanissery It is essential to maintain a patch of weeds or vegetation in the row middles to hold the soil from eroding and, at the same time, without being a source for weed invasion into the tree rows (Figure 1). Below are some quick tips for managing the vegetation in row-middle spaces between the citrus tree rows: MOW …
Assessing the Safety of a Water Distribution System
By Taylor O’Bannon, Matt Krug and Michelle Danyluk The U.S. Food and Drug Administration recently proposed changes to the pre-harvest Agricultural Water (Subpart E) section of the Food Safety Modernization Act Produce Safety Rule (PSR). Removing the annual water distribution system inspection is not one of the proposed changes. Rather, water testing for generic E. coli and developing a microbial …
Gibberellic Acid Not Recommended in Spring for HLB Trees
By Tripti Vashisth Recent research has shown benefits of gibberellic acid (GA) application (monthly from September to January) in improving yield and canopy density of HLB-affected trees. These findings have caught the attention of Florida citrus growers. Many have indicated that they are applying GA in their groves as per the University of Florida Institute of Food and Agricultural Sciences …
Battling Black Spot
By Megan Dewdney Editor’s note: This article originally stated that citrus black spot was in Hardee County. It should have said Hendry County, and has now been corrected. Citrus growers in Florida continue to battle new pests and diseases. They have been learning to manage citrus black spot for the last 12 years. The disease is still localized mainly in …
Put Predators to Work Against Lebbeck Mealybug
By Eric Middleton and Lauren Diepenbrock Lebbeck mealybug is an emerging pest in Florida citrus. Infestations can damage fruit, flowers and branches. The pest can even kill young trees in severe cases. Lebbeck mealybug is often difficult to manage with insecticides alone due to the pest’s tendency to feed in protected spaces and the thick wax that covers adult mealybugs …
Growers to Gather at Citrus Institute
By Chris Oswalt, Mongi Zekri, Ajia Paolillo and Lourdes Pérez Cordero Huanglongbing (HLB) continues to impact citrus-producing areas of Florida. The 2022 Florida Citrus Growers’ Institute is an opportunity for Florida citrus growers to come together to learn about effective management of HLB and other challenges affecting the industry. This year’s event will be held Tuesday, April 5 from 8:30 …
Pointers for Pre-emergent Herbicide Use
By Ramdas Kanissery Weeds emerging in citrus rows are problematic as they compete for resources with the trees, support pests and interfere with grove operations like irrigation (Figure 1). Hence, effective strategies to control weed emergence should be in place. Pre-emergence (or residual) herbicides are an excellent tool for the long-term suppression of weeds in tree rows. These herbicides …