By Amir Rezazadeh Saline soil and water damage many citrus groves in Florida. In general, when the dissolved salt concentration in soil or water increases, it is referred to as “saline” soil or water. But how much increase in salt concentration makes soil or water saline? Citrus plants’ major reactions to excessive salt in the soil or water are reduced …
Get the Newest UF/IFAS Info at the Citrus & Specialty Crop Expo
By Jamie Burrow and Ruth Borger Over the last several months, the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) citrus team has been preparing for the annual Citrus & Specialty Crop Expo. The excitement is in the air as many faculty are preparing seminar presentations on valuable information that growers may use today to support their operations. …
It’s Almost Time to Spray Gibberellic Acid
By Tripti Vashisth Gibberellic acid (GA) can benefit citrus trees in many ways. GA can improve vegetative and fruit growth while reducing fruit drop and flowering intensity. Evidence is mounting that repeated application of GA is needed to induce the desired positive effect on fruit growth and tree productivity. In a multiyear field trial on Valencia orange, monthly application of …
Managing Macronutrients and Micronutrients
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 …
ACP Detection Response: ‘The System Is Working’
County and state officials in California have been actively responding to various Asian citrus psyllid (ACP) discoveries in the Central Valley in recent weeks. Kern, Tulare and Fresno counties have all reported an ACP detection over the last month. The Citrus Pest and Disease Prevention Division (CPDPD) has been implementing delimitation protocols and necessary treatment programs. CPDPD Director Victoria Hornbaker …
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 …
Fruit Flies Are Major Cause of Fruit Drop in Brazil
Brazil’s Fundecitrus recently pointed out that fruit flies, along with citrus fruit borers, are primarily responsible for the country’s citrus fruit drop. The organization suggested that monitoring and management must be taken to avoid economic damage, since fruit flies occur throughout the year. Fundecitrus described the fruit flies that cause damage in Brazil and suggested control measures. Two species of …
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 …
ACP Found at Packinghouse and Juice Plant in California
The California Department of Food and Agriculture (CDFA) recently urged all citrus industry members to be extra vigilant in their Asian citrus psyllid (ACP) mitigation steps and adherence to regulatory practices. The request is in response to ACP detections in the Central Valley over the last few weeks. ACP is the vector of HLB disease. Multiple ACP were detected on …
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 …
Diagnosing Herbicide Phytotoxicity in Citrus
By Ramdas Kanissery, Nimal Timilsina and Ruby Tiwari Chemical weed control is an essential component of the toolbox to keep weeds in check in citrus groves. Citrus growers primarily rely on herbicide to manage weeds due to their efficacy and cost-effectiveness. Despite their benefits, herbicides may have a wide range of unintended effects on citrus. For instance, an herbicide-related injury …
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. …