Using Technology to Support Citrus Management Decisions

Josh McGillTechnology

By Yiannis Ampatzidis and Sandra M. Guzmán Pests and diseases, nutrient deficiencies, tree stress from environmental conditions and other factors can be overwhelming. The arrival of sensors and small unmanned aerial vehicles (UAVs) make it possible to gather large amounts of data to assess risk factors and estimate possible crop performance scenarios based on the availability of resources. At the …

A Two-Pronged Approach to Suppress Psyllids

Josh McGillHLB Management, Psyllids, Research

By Bryony C. Bonning and Lukasz L. Stelinski Asian citrus psyllids (ACP) transfer the pathogen that causes citrus greening from plant to plant as they feed. After confirmation of citrus greening in Florida in 2005, growers intensified their use of insecticides against ACP to try to stop disease spread. However, this method alone has yielded variable success and increased costs. …

Impact of HLB on Fruit Growth and Retention

Josh McGillFruit Drop, HLB Management

By Tripti Vashisth and Mary Sutton Citrus trees affected by huanglongbing (HLB) consistently have small fruit and low fruit numbers at harvest. The low fruit numbers are largely attributed to the increased rates of preharvest fruit drop that accompany HLB. Small fruit is more likely to drop during this preharvest period, suggesting a link between fruit size and retention. To …

First U.S. Detection of Citrus Yellow Vein Clearing Virus

Josh McGillCalifornia Corner, Diseases

The first detection of citrus yellow vein clearing virus (CYVCV) has been made in Tulare, California. The disease was detected during the California Department of Food and Agriculture’s (CDFA) routine multi-pest survey. The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) has confirmed positive identifications of the disease. CDFA is surveying for the disease in Tulare County …

What’s Next for the Donaldson Citrus Variety?

Josh McGillHLB Management, Research

During this summer’s Florida Citrus Industry Annual Conference, Matthew Mattia, a post-doctoral associate with the U.S. Department of Agriculture (USDA), discussed his work to identify the origins of the Donaldson citrus variety. The variety is a single tree on the USDA A.H. Whitmore Foundation Farm near Groveland, Florida. Mattia was the first to discover the tree on the farm in …

Evaluation of Citrus × Microcitrus Hybrid Scions

Josh McGillResearch, Varieties

By Ute Albrecht, Anas Fadli and Chandrika Ramadugu Most commercially available citrus scion cultivars are highly attractive to the Asian citrus psyllid and susceptible to HLB. There are some citrus species, however, that are HLB tolerant or resistant. This may be because they are less attractive to the psyllids and/or because they restrict pathogen proliferation and therefore HLB disease development. …

Protecting Citrus Trees From Heat Stress

Josh McGillTip of the Week, Weather

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 …

Experimenting With Cover Crops: Results From Three Years of Trials

Josh McGillCover Crops, Research, weeds

By Sarah Strauss, Antonio Castellano-Hinojosa, Davie Kadyampakeni, Ramdas Kanissery and Tara Wade Cover crops, which are planted specifically for soil enhancement and not for sale or harvest, can improve soil conditions and production for a variety of crops. However, there have not been many studies documenting changes to soil conditions and production when using cover crops in citrus. The University …

Forum for Growers Sparks Conversations

Josh McGillHLB Management, Pests

By Ajia Paolillo Florida citrus growers are undoubtedly under pressure while they work daily to maintain tree health and produce quality fruit that is profitable. Growers are constantly switching gears to budget increasing production costs, address labor issues and, of course, fight HLB and other problems in the grove. Growers are fighting HLB from many different directions, including enhanced nutrition, …

Heritage Practices for Today’s Challenges

Josh McGillCover Crops, Soil Improvement

By Brad Turner Cover cropping and composting in Florida citrus production are not new concepts. Our ancestors understood the basic principles and implemented these practices just a couple of generations ago. YESTERDAY AND TODAYAs a boy, I can remember an old citrus grower telling me how beggarweed and crotalaria, both native nitrogen-fixing legumes, growing wild in neighboring fields would be …

nutrient availability

Keeping Soil pH at the Optimal Level

Josh McGillNutrition, soil

By Brandon White This time of year is the end of the peak nutrient demand for citrus trees. Regardless of the types of fertilizer or inputs applied in the groves, trees have been taking up nutrients while growing in full tilt during the spring season. One of the greatest factors determining how well trees take up nutrients is soil pH. …

Keep CTV Under Control

Josh McGillDiseases, Tip of the Week

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 …

Pests, Pathogens and IPCs

Josh McGillIPCs, Pests, Research

By Lauren Diepenbrock, Megan Dewdney, Fernando Alferez, Jawwad Qureshi and Ozgur Batuman Individual protective covers (IPCs) are becoming commonplace in citrus production to support the development of young trees after planting. IPCs are made of fine mesh and are intended to keep Asian citrus psyllids (ACP) off young plants. Because ACP can transmit the pathogen that causes citrus greening/huanglongbing, preventing …

Phosphorus Recommendations and Soil pH Amendments

Josh McGillHLB Management, Nutrition, Soil Improvement

By Kelly T. Morgan and Davie Kadyampakeni Most information provided in the 2020 3rd edition of Nutrition of Florida Citrus Trees is still sound for healthy citrus trees under Florida production conditions. Past information on nutrients, application methods, leaf and soil sampling, and irrigation scheduling are also effective for management of huanglongbing (HLB)-affected trees. However, research conducted since HLB was …

Sneak Peek: April 2022 Citrus Industry

Josh McGillCitrus, HLB Management, Sneak Peek

Increased attention on nutrition has become part of the overall strategy for managing HLB. The April issue of Citrus Industry magazine includes several articles on nutrient management designed to help growers keep trees productive in the HLB era. Mandarin growers will want to take note of new University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) research on how …

Comparison of ACP/HLB Management Tools for Citrus Resets

Josh McGillDiseases, HLB Management, Research

By Lauren Diepenbrock, Megan Dewdney, Christopher Vincent and Davie Kadyampakeni As the threat of potential shutdowns loomed in March 2020, a University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) team put the final plants in the ground, individual protective covers (IPCs) on trees, and kaolin and pesticide applications on a 2.7-acre planting at the Citrus Research and Education …

IPCs Improve Fruit Yield and Quality

Josh McGillHLB Management, IPCs, Research

By Fernando Alferez, Ute Albrecht, Susmita Gaire, Ozgur Batuman, Jawwad Qureshi and Mongi Zekri University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researchers established a field trial in February 2018 to evaluate the efficacy of individual protective covers (IPCs) to prevent Asian citrus psyllids from spreading HLB and to study the effects on tree growth and physiology. The …

Balancing Citrus Nutrition in the Era of HLB

Josh McGillHLB Management, Nutrition, Research

The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) has committed to updating nutrition recommendations for citrus now that HLB is endemic across the state. Some of this ongoing research was discussed during the February All In For Citrus podcast. Growers will be interested to hear from Davie Kadyampakeni, a UF/IFAS assistant professor of soil and water science, …

Growers to Gather at Citrus Institute

Josh McGillHLB Management, Research, Tip of the Week

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 …