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State and federal policies in the United States focus on agricultural best management practices (BMP)—such as improving nutrient management—to address water quality issues. BMP development is a challenging process as a new BMP may also affect farm profitability. This article explores the economic feasibility of nitrogen (N) management programs, including nitrogen application rates (N rates), given alternative scenarios for current nitrogen use and producer risk perceptions of carrot production in Florida. In this study, eight alternative N rates are ranked to find the economically optimal BMP. Carrot profitability is determined based on carrot yields per hectare, input costs, and carrot sale prices, using data from a 2-year carrot production experiment. The analysis applied stochastic simulation to account for the uncertain factors by using Simetar Add-In for Excel. We found that 224 kg·ha−1 N fertilizer rate is the most preferred by the producers among the eight rates considered. According to Florida’s agricultural water policy, BMP recommendations should balance water quality improvements and agricultural productivity. We consider the potential reduction of nitrogen fertilizer rate BMP from 224 kg·ha−1 to 168 kg·ha−1 and show that the effect of such reduction depends on producers’ current fertilizer application rates and their risk aversion levels. For example, reducing the N fertilizer rate from 336 kg·ha−1 to 168 kg·ha−1 decreases mean net returns by only 2% ($49/ha). In contrast, reducing the nitrogen fertilizer rate from 224 kg·ha−1 to 168 kg·ha−1 reduces the mean net returns by $151/ha, with an almost 10% reduction in the certainty equivalent of the net returns (for extremely risk-averse producers). Overall, if most producers in the region are very or extremely risk-averse, and if most of them operate close to the optimal level of fertilizer use, then setting the more restrictive BMP of 168 kg·ha−1 N can be perceived as undermining their economic profitability and require significant cost-share incentives to ensure targeted 100% adoption of BMP recommendations.

Various nitrate and potassium "quick-test" kits for vegetable plant sap-testing have been calibrated for use on Florida vegetables. The objective has been to find a system that growers can use in the field to help manage nitrogen (N) and potassium (K) fertilizer—especially for drip-irrigated vegetables. The following guidelines should help individuals who are currently using—or are interested in using—sap-testing. Revision by George and Robert Hochmuth published by the UF/IFAS Horticultural Sciences Department; 6 pages.https://edis.ifas.ufl.edu/cv004

Watermelon (Citrullus lanatus) is a high nutrient crop, high in vitamins and very popular in the U.S and globally. The crop was harvested from 101,800 acres with a value of $560 million in the U.S (USDA-NASS, 2020). California, Florida, Georgia and Texas are the four-leading watermelon-producing states in the U.S. During the fall season of 2020, plants in two North Florida watermelon fields, one in Levy County (~20 acres) and one in Suwannee County (~80 acres) with varieties Talca and Troubadour, respectively, exhibited viral-like symptoms. The fields had 100% disease incidence that led to fruit quality issues and yield losses of 80% and above. Symptoms observed in the watermelon samples included leaf crumpling, yellowing and curling, and vein yellowing similar to that of single/and or mixed infection of cucurbit leaf crumple virus (CuLCrV; genus: Begomovirus, family: Geminiviridae), cucurbit yellow stunting disorder virus (CYSDV; genus: Crinivirus, family: Closteroviridae) and squash vein yellowing virus (SqVYV; genus: Ipomovirus, family: Potyviridae), although the vine decline symptoms often associated with SqVYV infection of watermelon were not observed. All three viruses are vectored by whiteflies and previously described in Florida (Akad et al., 2008; Polston et al., 2008; Adkins et al., 2009). To confirm the presence of these viruses, RNA was isolated from 20 symptomatic samples using the RNeasy Plant Mini Kit (Qiagen, USA) as per protocol. This was followed by RT-PCR (NEB, USA) using gene-specific primers described for CuLCrV, CYSDV and SqVYV (Adkins et al., 2009). Amplicons of expected sizes were obtained for all the viruses with the infection of CuLCrV in 17/20, CYSDV in 16/20, and SqVYV in 8/20 samples. In addition, the presence of cucurbit chlorotic yellows virus (CCYV; genus: Crinivirus, family: Closteroviridae) in mixed infection was confirmed in 4/20 samples (3 leaves and 1 fruit) by RT-PCR with primers specific to the CCYV coat protein (CP), heat shock protein 70 homolog (HSP70h) and RNA dependent RNA polymerase (RdRp) designed based on the available CCYV sequences (Sup Table. 1). The RT-PCR amplification was performed using a symptomatic watermelon sample and the amplicons of RdRp, HSP70h and CP were directly sequenced by Sanger method, and the sequences of the amplicons were deposited in GenBank under the accession number: MW527462 (RdRp, 952 bp), MW527461 (HSP70h, 583 bp) and MW527460 (CP, 852 bp). BLASTn analysis demonstrated that the sequences exhibited an identity of 99% to 100% (RdRp and HSP70h, 100%; and CP, 99%) with the corresponding regions of the CCYV isolate Shanghai from China (accession number: KY400636 and KY400633). The presence of CCYV was further confirmed in the watermelon samples by ELISA (Loewe, Germany) using crude sap extracted from the RT-PCR-positive, symptomatic watermelon samples. CCYV was first identified in Kumamoto, Japan in 2004 on melon plants (Gyoutoku et al. 2009). The CCYV was previously reported on melon from Imperial Valley, California (Wintermantel et al., 2019), and more recently on squash in Tifton, Georgia (Kavalappara et al., 2021) and cantaloupe in Cameron, Texas (Hernandez et al., 2021). To our knowledge, this is the first report of CCYV on field watermelon production in the U.S. Continued monitoring of the CCYV in spring and fall watermelon crop, and cucurbit volunteers and weeds will be critical toward understanding the spread of this virus and its potential risk to watermelon in Florida and other regions of the U.S.

Worldwide, commercial greenhouse vegetable producers currently use numerous production systems. Among the more prevalent include lay-flat bag or upright container culture, trough culture, rockwool, vertical culture, nutrient film technique (NFT), and ground (in-soil) culture. Many modifications of these basic production systems are presently in use, and most are appropriate for Florida, except for unamended ground culture. This revised 8-page fact sheet was written by Dan Fenneman, Michael Sweat, George Hochmuth, and Robert Hochmuth, and published by the UF Department of Horticultural Sciences, October 2012. HS785/CV263: Production Systems—Florida Greenhouse Vegetable Production Handbook, Vol 3 (ufl.edu)

In 2012, it was estimated that 500 acres or more of all edible crops were being grown in some type of protected culture in Florida. This revised 13-page fact sheet discusses some of the alternative or specialty crops being grown and marketed. Written by R. Hochmuth and D. Cantliffe, and published by the UF Department of Horticultural Sciences, October 2012. HS791/CV272: Alternative Greenhouse Crops—Florida Greenhouse Vegetable Production Handbook, Vol 3 (ufl.edu)

More and more farmers are growing small crops of fruits and vegetables for specialty local markets. They commonly grow several crops at different stages of development at the same time, so they have a variety of produce to sell to customers. This forces farmers to make several fertilizer calculations because of their diverse crop demands, because water and nutrient requirements vary according to the crop and stage of development. This 7-page fact sheet helps growers correctly interpret fertilizer recommendations and calculate accurate fertilizer amounts to be used based on crop nutrient requirements. Written by Jim DeValerio, David Nistler, Robert Hochmuth, and Eric Simonne, and published by the UF Department of Horticultural Sciences, October 2012. HS1206/HS1206: Fertigation for Vegetables: A Practical Guide for Small Fields (ufl.edu)

HS1164, a 3-page illustrated fact sheet by Danielle D. Treadwell, Robert Hochmuth, Linda Landrum, and Wanda Laughlin, provides an overview of this new type of market crop and its production. Includes references. Published by the UF Department of Horticultural Sciences, April 2010. HS1164/HS1164: Microgreens: A New Specialty Crop (ufl.edu) A minor revision of this article was published September 2020, here: https://journals.flvc.org/edis/article/view/123356

HS405, an 8-page illustrated fact sheet by Richard Tyson, Robert Hochmuth, and Daniel J. Cantliffe, provides an overview of hydroponic vegetable production in Florida — history, marketing considerations, growing systems, seasonal limitations, and economic considerations. Includes references. Published by the UF Department of Horticultural Sciences, November 2009. HS405/HS405: Hydroponic Vegetable Production in Florida (ufl.edu)

SL-293, a 9-page illustrated fact sheet by George Hochmuth, Robert Hochmuth, and Rao Mylavarapu, answers vegetable producers’ questions about what poultry manure and litter are, what plant nutrients they contain, considerations for using them, results of research in Florida, how to use it in a mulched-bed system, and how to collect and submit for testing poultry manure samples. Includes references. Published by the UF Department of Soil and Water Science, October 2009. SL 293/SS506: Using Composted Poultry Manure (Litter) in Mulched Vegetable Production (ufl.edu)

HS-1144, a 28-page illustrated fact sheet by Eric Simonne, Robert Hochmuth, Jacque Breman, William Lamont, Danielle Treadwell, and Aparna Gazula, presents the principles behind drip irrigation and some practical guidelines for successful and profitable use of drip irrigation for vegetable production in Florida. Includes references. Published by the UF Department of Horticultural Sciences, June 2008. HS1144/HS388: Drip-Irrigation Systems for Small Conventional Vegetable Farms and Organic Vegetable Farms (ufl.edu)

Effect of the ectoparasitic mite, Coccipolipus epilachnae Smiley, on feeding, fecundity, and longevity of adult Mexican bean beetle (MBB), Epilachna varivestis Mulsant, was determined in the laboratory. Field-collected, overwintered adult MBB were tested at 17, 22, 27, and 32°C. Laboratory-reared adult MBB were tested at 22°C. All MBB populations were tested with soybeans, Glycine max (L.) Merrill, as the host plant. Mite infestations had no significant effect on total leaf area consumption, total number of eggs deposited, or longevity of adult MBB.

Plots were established in a commercial potato field near Little Creek, De.on 2 May. Soil type was a sandy loam with a high moisture content due to persistent, heavy rains. Each plot consisted of 3 rows (0.9 m apart) 6 m long. The plots were arranged in a randomized complete block design in which treatments were replicated four times. Only the middle row of each plot received treatment. The outside rows served as a reservoir for the CPB. The granular insecticides were applied using a single row Noble applicator. The seed furrows were opened with a commercial planter, the insecticides applied and the seed pieces placed in the furrow by hand. The furrows were then closed. The drag-off treatment was applied on 11 May by dispensing the insecticide as a 5-inch band over the hills immediately before drag-off. At the first cultivation on 6 Jun, the appropriate insecticides were applied as a sidedress in the cultivation furrow.

Tests were conducted in a no-till field planted Jul 2 in 38 inch rows after wheat. At time of treatment, the corn averaged 3 ft (mid whorl stage) and damage was heavy with 0.5-2 larvae/plant. Treatment plots were 4 ft x 15 ft rows for foliar sprays and 2 ft x 15 ft rows for granular treatments arranged in a randomized complete block design with 4 replicates. Treatments were made on Aug 6. Sprays were applied with a back pack CO2, boom sprayer calibrated to deliver 40 gpa at 32 psi. Granular treatments were applied by hand shaker cans over the whorl. Post-treatment counts of larvae were made on 10 plants selected at random from the center 2 rows of each plot Jul 7.

Tests were conducted on 2 farms, Poplar Hill Research farm, Quantico, Wicomico County and Snow Hill, Worcester County. At time of treatment, corn at both locations was near the tassel or late whorl stages, Treatment plots were four 15 ft rows arranged in a randomized complete block design with 4 replicates. Pre-counts were taken on Jul 30 at Snow Hill and Aug 10 at Poplar Hil.

Tests were conducted in a 2-yr-old production alfalfa stand in Baltimore County. Pre-counts were made on May 12 and weevil larvae averaged 39 per dip sweep of a 15 inch standard size net. Treatment plots were 10 ft x 15 ft and arranged in a randomized complete block design with 4 replicates. Plots were sprayed on May pack sprayer calibrated to deliver 10 gpa at 30 psi. Plots were sampled for post-counts on May 19.

Essex variety of soybeans were planted on May 16 in 30 Inch rows in Queen Anne’s County, MD. Treatment plots were 4 x 15 ft rows arranged in a randomized complete block design with 4 replicates. Treatments were applied on Sep 8 with a back pack sprayer hand-held CO2 pressure boom sprayer calibrated to deliver 14 gpa at 40 psi with hollow cone nozzles. Populations at time of treatment were light, and most larvae (ca 80%) were pupating. Post-treatment larval counts were taken 24 hr after treatment. Each count consisted of 2 random 3 ft shake cloth samples taken within the center 2 rows of the plot.