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Internal bruising (IB) caused by handling impacts results in disruption of normal ripening in tomato (Lycopersicon esculentum Mill.) locular gel. It was selected as an injury indicator to investigate the effect of drop height (O, 10, 20, 30 cm) onto an unpadded surface and number of impacts (one or two) for three tomato cultivars. For mature-green (MG) tomatoes, significant incidence of IB (5% to 45%) was found in all cultivars for single drops on opposite sides of fruits from 20 cm; two drops on the same location from 20 cm caused 20% to 30% IB. Breaker-stage (BR) tomatoes were more sensitive to impacts than MG. Single drops from 10 cm on opposite sides of BR fruits caused 15% to 73% IB, depending on cultivar. Two drops on a single location from 10 cm caused 50% to 68% IB. `Sunny' was less susceptible to IB than `Solar Set' or `Cobia' (formerly NVH-4459).

Roma tomatoes (‘BHN 467’) were hand-harvested at mature-green color stage and treated with ethylene (100 μL·L⁻¹ at 20 °C and 90% relative humidity) until reaching breaker (<10% red), pink (30%–60% red), or light-red ripeness stage (60%–90% red). Individual fruit at each ripeness stage were subjected to double impacts over the locule using a pendulum-impact device with a force equivalent to two 40-cm drops, followed by ripening at 20 °C. Fruit exhibited most noticeable increases in respiration and ethylene production within 1 hour and 1 day after impact, respectively. After 24 hours, respiration rates increased 40%–60% regardless of ripeness stage, while ethylene production in impacted breaker-stage fruit increased 3-fold (to 6.7 μL·kg⁻¹·h⁻¹). Fruit impacted at breaker stage softened 2 days earlier compared with non-impacted breaker fruit. Fruit impacted at all ripeness stages had higher electrolyte leakage and polygalacturonase (PG) activity during ripening than non-impacted fruit. After 6 days, electrolyte leakage in fruit impacted at light-red ripeness stage was 23% higher than non-impacted fruit; PG activity in breaker fruit increased 40% at 10 days over non-impacted fruit. No changes were observed for soluble solids content, total titratable acidity, pH, or sugar/acid ratio from impacts, independent of ripeness stage.

To remain competitive for federal and state funding, state cooperative extension services must proactively incorporate issues programming and performance-based budgeting. State major program (SMP) design teams, which provide linkages between clientele groups and the research base, must conduct needs assessments to adjust to this new atmosphere of accountability. A case study illustrates how one Florida SMP (FL107, vegetable production, harvest, handling and integrated pest management in Florida) restructured its design team to become more flexible and proactive to target a wider range of outcomes. While still in the implementation phase, this model has already resulted in improved communication within the organization, better addressing extension needs at county level while facilitating reporting at the state level.

Blueberry is widely grown around the world, and the United States is the leading producer. A strategy to maintain fruit quality during commercial handling is rapid cooling using the forced-air system. Hydrocooling (HY) is an effective cooling method widely used for many crops and has potential as a cooling method for blueberry. The objective of this study was to compare the cooling efficiency of conventional forced-air cooling (FA), the current commercial method, with immersion HY alone or HY in combination with FA (HY + FA), and to determine effects on blueberry fruit quality during subsequent cold storage. ‘Emerald’ and ‘Farthing’ southern highbush blueberry were commercially harvested and packed into plastic clamshell containers. FA was accomplished by simulating commercial conditions using a small-scale unit within a cold room at 1 °C/80% relative humidity (RH) until 7/8 cooling was achieved (27 minutes). For HY, fruit in clamshells (125 g) were immersed in chlorinated ice water (200 ppm free Cl⁻¹, pH = 7.0) and 7/8 cooling occurred in 4 minutes. For HY + FA, fruit were 7/8 hydrocooled then transferred to FA for 30 minutes to remove free water from the fruit. After the cooling treatments, clamshells were evaluated weekly for selected quality parameters during 21 days storage at 1 °C. For HY treatment, the 1/2 cooling time was 1.13 minutes for ‘Emerald’ and 1.19 minutes for ‘Farthing’, whereas for FA treatment, the 1/2 cooling times were 4.5 and 6.8 minutes, respectively. For ‘Farthing’, cooling method did not affect fruit firmness; after 21 days, there was a slight softening in fruit from all treatments. However, ‘Emerald’ fruit cooled by HY + FA were softer than those from either HY or FA after 14 days of storage. For all cooling methods ‘Emerald’ was less acidic (0.3% citric acid) and was sweeter [10.2% soluble solids content (SSC)] than ‘Farthing’ (0.6% citric acid, 9.4% SSC). There were no differences in bloom among cooling methods. Bloom ratings for ‘Emerald’ remained >4.5 (70% to 80% coverage) whereas that for ‘Farthing’ cooled by HY or HY + FA was 3.7. Anthocyanin concentration in ‘Emerald’ fruit from HY + FA cooling method decreased by 33% during 21 days of storage, whereas that for ‘Farthing’ remained constant (8.3 mg cyanidin-3-Glicoside/g) irrespective of treatment during storage. Compared with ‘Farthing’, ‘Emerald’ was more sensitive to HY, where ≈15% of fruit developed visual skin breaks (split) after 7 days storage. HY shows potential as an alternative method to rapidly and thoroughly cool southern highbush blueberries such as ‘Farthing’, thus, maintaining fruit quality, while introducing a rinsing and sanitizing treatment. HY needs to be tested on commercial cultivars to determine the incidence of fruit splitting.

Tomato (Lycopersicon esculentum Mill.) fruit, cv. Solar Set, were harvested at the mature-green stage and treated with 50 μL·L^-1 ethylene at 20 °C. Individual fruits at the breaker stage (<10% red color) were dropped onto a solid surface to induce internal bruising. Dropped and undropped fruit were stored at 20 °C until red-ripe, at which time pericarp, placental, and locule tissues were excised. Tissues from dropped tomatoes were examined for evidence of internal bruising and all tissues were analyzed for selected volatile profiles via headspace analysis. Individual volatile profiles of the three tissues in bruised fruit were significantly different from those of corresponding tissues in undropped, control fruit, notably: trans-2-hexenal from pericarp tissue; 1-penten-3-one, cis-3-hexenal, 6-methyl-5-hepten-2-one, cis-3-hexenol and 2-isobutylthiazole from locule tissue; and 1-penten-3-one and β-ionone from placental tissue. Alteration of volatile profiles was most pronounced in the locule tissue, which was more sensitive to internal bruising than the other tissues. Changes observed in the volatile profiles appear to be related to disruption of cellular structures.

`Camelot' bell pepper was grown in a N fertigation study on sandy soil using polyethylene-mulched and fumigated beds. Portions of N (0%, 33%, 67%, 100% of total season N) were applied at bed formation. The remaining N was injected weekly into the drip irrigation system. Total N application treatments were 64, 128, 192, and 256 kg·ha^–1. Early and total-season marketable fruit yields increased linearly with N rate. Preplant fertilizer proportion did not influence early yields, but late and total-season marketable fruit yields decreased linearly as preplant fertilizer proportion increased. Petiole sap NO₃-N concentration increased with increasing N rates, but decreased linearly as preplant fertilizer proportion increased. Petiole sap NO₃-N concentrations fell below critical levels for all N rates and preplant fertilizer proportions early in the season. Whole-leaf N concentrations were higher than critical values (>40 g·kg^–1) throughout the season. Preplant fertilizer proportion had a significant linear effect on whole-leaf N concentrations for all sampling periods. Petiole sap was better correlated to yield data than whole-leaf N.

Early-maturing potato cultivars (Solanum tuberosum L.) grown in many subtropical and tropical regions are typically packed and shipped without curing. The objective of this study was to evaluate two early-maturing potato cultivars (‘Fabula’ and ‘Red LaSoda’) grown under four nitrogen fertilizer (NF) rates and harvested at three intervals after vine kill for effects on tuber physical and compositional quality at harvest and during storage. NF was applied through fertigation (0, 112, 224, or 336 kg·ha⁻¹) and compared with granular NF application (224 kg·ha⁻¹). The tubers were harvested weekly after vine kill (H1, H2, and H3) then evaluated for quality at 7 and 14 days during storage at 10 °C/80% to 85% relative humidity (RH). ‘Fabula’ tubers from H1 had the highest cumulative weight loss (3.6%) after 14 days of storage (season 1), while those from both H1 and H2 were highest (4.4%) in season 2, regardless of NF application method or rate. Tuber firmness increased by 1.5 newtons (N) for tubers from H1 after 7 days storage, and again by 0.76 N after 14 days for tubers from H2 and H3. Periderm dry matter content (DMC) for H1 tubers increased to 13.9% after 7 days, regardless of fertilizer treatment, in contrast to those from H2 or H3 where DMC remained constant throughout storage (10.6% and 11.4%, respectively). For ‘Red LaSoda’, cumulative weight loss in season 1 for H1 tubers was 2.2% after 14 days storage, whereas that for H2 and H3 tubers averaged 0.7%; this trend was similar for season 2. Periderm DMC significantly increased with increased storage time; that for H2 tubers was highest (19.6%) after 14 days. In both cultivars, tuber ascorbic acid content (AAC), soluble solids content (SSC), and total titratable acidity (TTA) remained constant throughout the 14-day storage period. Periderm maturity of ‘Fabula’ and ‘Red LaSoda’ potatoes had a greater effect on tuber physical and compositional quality during storage than the fertilizer rates or application methods. Fertigation at NF rates of 112, 224 or 336 kg·ha⁻¹ was comparable with conventional granular NF application for growing high-quality tubers with acceptable postharvest life. Growing tubers at 112 kg·ha⁻¹ nitrogen via fertigation has the potential to reduce both irrigation water usage and fertilizer runoff during the production cycle.

Strawberries are a high value commodity with a short shelf life. Florida is the largest producer of winter strawberries in the United States with 2,790 hectares of production, 90% are located in Hillsborough County. Many Florida growers apply additional calcium (Ca) as a foliar spray despite the lack of conclusive evidence of an increase in fruit quality or yield. It is believed that additional Ca will improve cell wall integrity through Ca linkages with pectins with in the cell wall and increase fruit firmness. Preharvest applications of calcium chloride have shown to delay the ripening of strawberry fruit and mold development. The objectives of this two year study were to determine the effects of Ca on yield, growth, and postharvest quality of strawberry when applied to the soil or as a foliar spray. `Sweet Charlie' strawberry plants were grown on a Seffner fine sand in Dover, Fla. The experimental design was a split-block replicated four times with soil and foliar Ca applications. Main plots consisted of a broadcast preplant incorporation of gypsum (calcium sulfate) 0 kg·ha^-1, 36.7 kg·ha^-1, and 73.4 kg·ha^-1. Sub-plots consisted of foliar applications of 400 mg·L^-1 Ca from calcium sulfate, 400 and 800 mg·L^-1 Ca from calcium chloride and a water control applied weekly throughout the 2002-03 and 2003-04 growing season. Yield data was collected twice weekly through out the growing season. Fruits were graded for quality based upon size, visual appearance of pathogens degradation, frost/water damage, and misshapen form. Calcium content was determined for leaves, fruit, and calyxes in January and March. Postharvest quality evaluations of pH, titratable acidy, soluble solids, and firmness (Instron 4411) were determined in January and March.

Controlled-release fertilizer (CRF) use is a best management practice that may reduce nitrogen (N) loss to the environment. Several factors affect CRF nutrient release; therefore, including CRF in a fertilization program may have challenges. Thus, the study objective was to evaluate the effects of CRF N rate, source, release duration, and placement on seepage-irrigated marketable tomato (Solanum lycopersicum L.) yield, leaf tissue N (LTN) concentration, post-season soil N content, and postharvest fruit firmness and color. There were two soluble fertilizer (SF) controls [University of Florida/Institute of Food and Agriculture Sciences (UF/IFAS) (224 kg·ha⁻¹) and grower standard (280 kg·ha⁻¹)] and six and seven CRF treatments (alone or in combination with SF) in Fall 2011 and 2012, respectively. Cumulative rainfall totaled 31.4 and 37.4 cm during the 2011 and 2012 seasons with average air temperatures of 22.4 and 22.1 °C, respectively. Soil temperatures ranged from 14.2 to 40.6 °C in 2011 and 11.1 to 36.6 °C in 2012 with a strong correlation (r = 0.95) to air temperature. Controlled-release urea resulted in 7.5% to 17.9% plant mortality in 2011 and reduced yields in 2012 compared with CRF N–phosphorus–potassium (NPK) at a similar N rate. LTN concentrations were above or within the sufficiency range for all treatments. In 2011, using CRF-urea at 190 kg·ha⁻¹ N produced similar marketable tomato yield in all fruit categories except season total large tomatoes, which produced significantly fewer marketable tomatoes with 13.5 Mg·ha⁻¹ compared with UF/IFAS and grower standard with 17.9 and 14.2 Mg·ha⁻¹, respectively. In 2012, CRF-NPK (168 kg·ha⁻¹ N) significantly reduced first and second harvest combined large and season total large and total marketable yields compared with the UF/IFAS rate and grower standard treatments. Marketable yield was not significantly affected by CRF (urea or NPK) release duration, but CRF-NPK 180-day release duration significantly increased residual soil N in 2012 compared with CRF-NPK 120-day release with 74.2 and 34.3 kg·ha⁻¹ N, respectively. Rototilling CRF-urea into the bed, which was only evaluated in 2011, significantly increased total season yields compared with CRF-urea broadcast in row before bedding (BIR) with 43.0 and 46.5 Mg·ha⁻¹, respectively. There were no significant yield differences when 50% or 75% of the total N was CRF placed in the hybrid fertilizer system, which is a system with CRF placed BIR with the remaining N as SF-N banded on the bed shoulders. No significant differences among treatments were found for total residual soil N in 2011; however, higher soil N remained in CRF (NPK and urea) treatments compared with SF treatments in 2012, except for Treatment 9. No significant differences were found among treatments for fruit firmness or color in 2011 or 2012. CRF-NPK at 190 to 224 kg·ha⁻¹ N with a 120-day release may be recommended as a result of similar or greater first harvest and total season marketable yields compared with IFAS-recommended rates and low residual soil N. Further research must be conducted to explore CRF placement and percentage urea composition, although use of the hybrid system or rototilling may be recommended.

Pink rib discoloration or pinking in the midribs of lettuce (Lactuca sativa) leaves is a stress-induced disorder that leads to crop loss worldwide. Maintaining recommended field and postharvest conditions reduces its incidence but does not eliminate the issue. During the past decade, research has identified the tolerance of this disorder among lettuce types and cultivars grown in cooler climates. However, tolerance to pink rib among lettuce types grown in humid subtropical climates is unknown; therefore, it is necessary to screen lettuce germplasm under these growing conditions. During this study, diverse lettuce accessions were planted for early-season, mid-season, and late-season harvests over two seasons in Belle Glade, FL, USA. Harvested midribs were wounded to induce pink rib, stored for 6 to 9 days at 5 °C and >95% relative humidity, and rated for severity using a 5-point subjective scale. Genotype × environment interactions were evaluated to understand the environmental factors that favor the development of pink rib during storage and between planting seasons. Pink rib severity increased during storage, with the highest increase observed after 3 to 4 days in both seasons. After 9 days of storage, lettuce accessions with the least pink rib for each leaf type were identified. The lowest pink rib ratings after 9 days of storage were “moderate” (rating of 3) for crisphead, Latin, and romaine, “slight” (rating of 2) for butterhead types, and “none” (rating of 1) for leaf types. Additionally, pink rib severity increased among accessions during the late spring season harvest when field temperatures were higher and daylight hours were extended. The lettuce germplasm with low susceptibility to pink rib is promising to breed lettuce lines for future research.