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Relatively few herbicides are registered in Alabama or in the southeastern United States for use in annual hill plasticulture production of strawberries. Acquisition of 24(c) special local needs status for certain herbicides could make more of these chemistries available to the strawberry industry. These herbicides, especially when applied as tank mixes pose potential risks to strawberry plant growth and fruit yield. Special local needs status for these herbicides has been granted for other states, but more evaluation of these products in Alabama soils under plastic mulch is needed. The objective of this study was to assess tank mix applications of preemergence herbicides with different modes of action on plant growth, crop yield, and fruit size of ‘Camarosa’ strawberry. A study was conducted at the Chilton Research and Extension Center in Clanton, AL, in 2018 and 2019. Pendimethalin (3.5 L·ha–1) and S-metolachlor (1.6 L·ha–1) were evaluated for potential phytotoxicity in ‘Camarosa’ strawberry when applied alone or in tank mixes with napropamide (8.6 kg·ha–1), sulfentrazone (0.3 L·ha–1), or terbacil (0.42 L·ha–1) by comparing them to a nontreated control. At 18 weeks after planting, pendimethalin tank mixed with napropamide reduced plant dry weight by 33% compared with the control, but this reduction was not significant. Additionally, tank mixes of pendimethalin with sulfentrazone, napropamide, and terbacil reduced shoot dry weight by 43%, 52%, and 43%, respectively, compared with pendimethalin alone. Pendimethalin + napropamide tank mix reduced relative growth rate by 95% compared with the control between 6 and 18 weeks after planting. All treatments were similar to the control in marketable yield. Differences in plant growth parameters did not appear to affect yield by the end of the experiment. All single applied treatments along with S-metolachlor tank mixed with napropamide and sulfentrazone; pendimethalin tank mixed with sulfentrazone and terbacil appeared to be safe for direct application to strawberry planting beds covered in polyethylene mulch.

Stink bugs (Hemiptera: Pentatomidae) are commonly monitored using pyramid traps baited with a pheromone. Initially, the pyramid traps were painted yellow and predominantly used to monitor native stink bug species. However, research studies involving the exotic Halyomorpha halys Stål (Hemiptera: Pentatomidae) now use pyramid traps that are black, not yellow. As H. halys moves across the southeastern United States, the use of a single trap, yellow or black, for monitoring and conducting research studies would be beneficial. Our objective was to compare black and yellow pyramid traps baited with a lure to determine if one was superior for trapping herbivorous stink bugs. This study was conducted at four locations, three in Alabama and one in Georgia, over 2 yr. Additionally, residual efficacy of the lure was measured via trap capture over 1-mo intervals. Our results showed that only when native stink bug species were combined, and only in 1 yr, were captures significantly affected by trap color. Capture of the exotic H. halys and the most abundant native species, Euschistus servus (Say), was not significantly affected by trap color. Trap capture was significantly affected by how long a lure was in a trap. The data from this study suggests that when traps are used in conjunction with a pheromone to monitor multiple species of adult stink bugs, especially native species, the yellow pyramid trap is favored.

Summary Goals: Bunch grape production in the southeastern United States is limited by the endemic bacterium Xylella fastidiosa, causal agent of Pierce’s disease (PD). University of California, Davis-bred PD-resistant 87.5% Vitis vinifera L. winegrape selections represent a new technology that can help sustain the viticulture industry in the southeastern U.S. by reducing pesticide inputs and diversifying grape production. PD-resistant vines were planted to determine viticultural performance and survival in central Alabama. We anticipated our results would indicate whether regional growers could feasibly grow PD-resistant, predominantly V. vinifera winegrapes under humid southeastern U.S. viticulture conditions. Key Findings: All evaluated selections grew vigorously under humid southeastern conditions. U0501-12 produced the highest pruning weight during the 2015 to 2016 period of study. U0502-10 was the most productive selection, as measured by total yield per vine, and had the largest clusters. Harvest soluble solids content was highest for selection U0501-12, while titratable acidity was lowest for U0502-01. All selections broke bud prior to historical late-spring frost-risk dates, although no injury was experienced in the years evaluated. U0502-10 began veraison between one and two months earlier compared to the other selections in both years. U0502-10 was also harvested 70 and 22 days prior to the next selection in 2015 and 2016, respectively. The experimental vines neither exhibited symptoms nor tested positive for PD during vine establishment. Under regional commercial management practices, no vine losses resulted from other pathogens. However, an aggressive disease management strategy will be mandatory to produce consistently clean fruit in the humid southeastern U.S. Impact and Significance: These results indicate grapevines with predominantly V. vinifera background can survive under humid viticulture conditions in central Alabama with the incorporation of alleles for PD resistance. Further research is necessary to refine management practices enabling sustainable production in the southeastern U.S. as PD-resistant grapevine cultivars become commercially available to regional producers.

In the humid subtropical climate of the southeastern region of the USA, commercial cultivation of European (Vitis vinifera L.) and hybrid bunch grapes has largely been prevented by the presence of Pierce’s disease (PD), a bacterial infection caused by Xylella fastidiosa, a Gram-negative bacterium endemic to the region. Consequently, only PD-resistant or -tolerant grape cultivars can currently be grown sustainably in the region. Yet, limited research has been conducted to evaluate the yield potential, fruit quality characteristics, and vine growth and development of PD-tolerant/-resistant hybrid bunch grape cultivars in the southeast. An experimental vineyard was established at the Sand Mountain Research and Extension Center, Crossville, AL, in 2008 with a main objective to evaluate the vegetative characteristics and cropping potential of ten PD-tolerant hybrid bunch grape cultivars. The experiment was a random complete block design with four replications. Studied PD-tolerant American and French-American hybrid bunch grape cultivars included ‘Black Spanish’, ‘Blanc du Bois’, ‘Champanel’, ‘Conquistador’, ‘Cynthiana’, ‘Favorite’, ‘Lake Emerald’, ‘Seyval Blanc’, ‘Seyval Blanc’ grafted on ‘Couderc 3309’ rootstock (‘Seyval Blanc’/3309C), ‘Stover’, and ‘Villard Blanc’. Based on 2011-2017 results for cumulative yield per vine, the most productive cultivars in our environment were ‘Favorite’ and ‘Villard Blanc’ (yielding 96.3 and 90.0 kg vine(-1) cumulative yield, respectively), while ‘Conquistador’ was the least productive, with 32.4 kg vine(-1) cumulative yield. ‘Blanc du Bois’ also produced high yields during the last three seasons. ‘Villard Blanc’ had the largest fruit clusters throughout the study period, while ‘Champanel’ consistently produced the largest berries, followed by ‘Blanc du Bois’ and ‘Villard Blanc’. Based on their overall performance ‘Villard Blanc’, ‘Black Spanish’, and ‘Favorite’ are considered suitable for sustainable commercial grape production in Alabama and the southeastern USA.

A series of experiments was conducted to evaluate variety selection and planting date for spring and fall season extension of tomato (Solanum lycopersicum L. (syn.: Lycoperisicon esculentum Mill.)) production in high tunnels in southeast Alabama. &lsquo, BHN 640&rsquo, &lsquo, Florida 91&rsquo, Sun Leaper&rsquo, and &lsquo, Carolina Gold&rsquo, were evaluated for early spring production in 2004. These varieties did not differ in total yield of marketable fruit, however, &lsquo, produced higher early yields compared with the other varieties. &lsquo, were evaluated for late-season extension in fall 2004. &lsquo, produced higher yields of large, medium, total marketable, and unmarketable fruit grades than &lsquo, In a study conducted in early 2005, higher yields of marketable fruit were produced from the first planting date (31 January) compared with the final of four planting date (25 Mar.). In summary, results indicated that season extension of tomato production in high tunnels was possible, with harvests three weeks earlier in the spring and 12 weeks later in the fall compared with typical field harvest dates. These early yields can command prices from $3.30 to $4.40US per kg of fruit.

Kiwifruit is a new emerging crop for the southeastern United States that requires cross-pollination to set fruit. However, the pollination requirements for varieties grown in the southeastern United States are unknown. Through insect surveys and a bagging experiment, we assessed the pollination requirements of two female kiwifruit cultivars (Actinidia chinensis var. chinensis ‘AU Golden Sunshine’ and A. chinensis var. chinensis ‘AU Gulf Coast Gold’). For each, fruit quantity (fruit set) and fruit quality (weight, size, seed count, firmness, soluble solid content, and dry matter) were compared among three pollination treatments (wind, insect, and artificial pollination). Low abundances of insects were observed visiting female flowers of both kiwifruit cultivars, and therefore likely minimally influenced kiwifruit pollination. Artificial pollination resulted in the greatest percentages of fruit set and marketable fruits, followed by insect and wind pollination. Artificial pollination resulted in fruits that were greater in weight, size, and contained more seeds, than insect- and wind-pollinated fruits. Firmness and soluble solid content did not vary greatly between pollination treatments, yet were greater in ‘AU Golden Sunshine’. Dry matter content did not vary greatly between pollination treatments or between each cultivar. To maximize yields and optimize fruit quality, these results suggest that kiwifruit producers should place more effort into artificial pollination compared to wind and insect pollination. Future research should explore the use of managed bees (e.g., honey bees and bumble bees) within kiwifruit orchards to determine ways to utilize them as a secondary source for pollination needs.

The development of more cold-tolerant short-cycle banana cultivars has made subtropical production possible, but fruiting may be unreliable in colder margins, such as the coastal region of Alabama, as a result of cold winter temperatures and other suboptimal growing conditions. Thus, the objectives of this study were to determine plant growth parameters that predict flowering, and to evaluate vegetative and reproductive growth of Cavendish and non-Cavendish banana cultivars. Pseudostem circumference and the height-to-circumference ratio (HCR) for tall cultivars and HCR for medium cultivars exhibited linear or quadratic relationships when regressed to the number of days from planting to inflorescence emergence (DPE), and hence were the best predictors of inflorescence emergence. The banana cultivars Double, Grand Nain, Cardaba, Ice Cream, and Goldfinger demonstrated cropping potential by producing mature bunches in the cooler environment of the subtropics and currently offer the best possibilities for banana production in Alabama.

To select plant species and species combinations for northern climates, mats with different plant species and species combinations were constructed on a green roof plant production farm and later transported and installed on an urban rooftop. There were three treatments: two different planting combinations, which together consisted of 10 diverse plant species [both stonecrop (Sedum) species and nonstonecrop species], and a control, which consisted of 26 stonecrop species used for standard mat production. Growth measurements and observations were made at both sites and special attention was paid to the performance of species during the harvest, transportation, and installation stages, as well as during recovery postinstallation. All species but false rock cress (Aubrieta cultorum) were found to be suitable for extensive green roof applications in northern climates, although there were variations of suitability among the species. Good, mediocre, and poor interactions formed between numerous species, displaying different levels of compatibility. Finally, all species were considered appropriate for a mat production system; species that failed to germinate, species planted postinstallation, the frequently displaced rolling hens and chicks (Jovibarba sobolifera), and false rock cress were exceptions. Overall, many species in this study displayed successful, well-rounded growth. Based on results, species and species combinations were recommended for extensive green roofs in northern climates.

Mini-watermelon [Citrullus lanatus (Thunb.)] cultivars Valdoria and Vanessa were evaluated at 20, 30, 40, or 50 days after anthesis to determine maturity at harvest. Fruit circumference, weight, ground spot color, and number of senescent tendrils were measured as external indicators for each watermelon. Soluble solids content (SS), pH, and SS:total acid ratio (SS:TA) of each watermelon were determined to provide an indication of internal maturity. Regression and Akaike Information Criterion fit statistics analyses were performed to determine significant relationships and best predictors for external indicators of internal maturity factors. In this study, external predictors were most closely linked to fruit pH rather than to SS or SS/TA. Of the external indicators tested, fruit weight, circumference, number of senescent tendrils, and International Commission on Illumination (CIE) b* color coordinate values of the ground spot were best related to fruit pH. According to the regression models, two completely senesced tendrils, a circumference of 53 cm, weight of 3 kg, and CIE b* coordinate ground spot value of 40 are each sufficient to predict maturity when pH is used as the internal indicator of maturity under the conditions of this experiment.

Okra (Abelmoschus esculentus ‘Clemson Spineless’) was grown on an Orangeburg sandy loam soil in Shorter, AL. Okra was direct-seeded in single rows. Treatments consisted of five mulch colors: black, white, red, silver, and blue installed either with or without spun-bonded row cover. Soil temperatures were 4 to 7 °C lower than air temperatures in all treatments. The use of darker (black, blue, red) -colored plastic mulches increased early and total yield of okra compared with bare soil with and without row cover. Increased soil and air temperatures did not always correlate to an increase in yield. It can be concluded that the use of dark plastic mulch is advantageous to growers of okra in climates that do not have cool springs, but the added use of row covers to plastic mulch has no effect on growth and yield. The profit of marketable okra produced using a row cover was $1.37 versus $1.35 per pound without a cover in 2003 and $1.28 versus $1.29 per pound in 2004. Blue plastic mulch is ≈$0.08 per foot more expensive than black plastic. Our data do not show an economic advantage for blue over black mulch for okra, but the positive effect cited by other authors may be more pronounced with leafy vegetables.

Row covers and colored plastic mulch are used routinely throughout the United States to grow vegetables but are rarely used in conjunction to produce a crop. Summer squash (Cucurbita pepo L.), cv. Prelude II, was grown on an Orangeburg sandy loam soil in Shorter, AL. The summer squash was direct seeded in single rows. The experiment consisted of 12 treatments including: (1) black plastic mulch (BPM)+spunbonded row cover (RC), (2) BPM alone, (3) white plastic mulch (WPM)+RC, (4) WPM alone, (5) red plastic mulch (RPM)+RC, (6) RPM alone, (7) bare soil (BS)+RC, (8) BS alone, (9) silver plastic mulch (SPM)+RC, (10) SPM alone, (11) blue plastic mulch (BLUPM)+RC, and (12) BLUPM alone. Year and mulch color affected all variables, row cover affected plant height and stem diameter, and the mulch color × row cover interaction affected yield variables. Mulch color and year significantly affected air and soil temperatures and row cover significantly affected air temperature. Soil temperatures were more than 5...

Controlled-release nitrogen fertilizers allow growers to reduce nitrogen loss from leaching in comparison to soluble formulations. Plant growth and nitrogen leaching during greenhouse production of Begonia × semperflorens-cultorum Hort. cv. “Brandy” (Begonia), Euphorbia pulcherrima Willd. ex Klotzch cv. “Freedom Red” (Poinsettia), Ficus benjamina L., and Nephrolepis exaltata (L.) Schott cv. “Bostoniensis” (Boston Fern) were evaluated for eight weeks using three commercial controlled-release nitrogen fertilizers in combination with phosphorus and potassium sources to maintain a 3 : 2:1 NPK ratio. Mini Polymer Coated Urea (MPCU) 41-0-0, Trikote 42-0-0, and Regalite Nitroform (RN) 38-0-0 were incorporated into the substrate at rates of 0.9 kg nitrogen (N) m−3 and 1.5 kg N m−3 prior to potting. Total soluble salts in the leachates reflected the initial leaching of salts from the substrate, some increase or maintenance of salt levels through the third week, and lower levels from the fourth through eighth w...

When vegetables are double-cropped on polyethylene mulch, fertilizer recommendations for each crop may need to be adjusted because liming and preplant applications are done prior to laying plastic. When current fertilizer recommendations for single crops were used for cucumber following tomato, the cucumber plants looked like green, indicating a nitrogen (N) and/or potassium (K) deficiency was developing, suggesting that nutrient availability for the second crop was not adequate for producing the highest yields. Therefore, the nutritional status of both crops was diagnosed using sufficiency range data and DRIS norms to determine which nutrient(s) was limiting crop nutrition. Regardless of N source used as a sidedress injection material (at a rate of 7 kg N ha−1wk−1 as ammonium nitrate or calcium nitrate) or liming material used to adjust soil pH to 6.5 (carbonate- or oxide-based calcitic or dolomitic lime), foliar levels of N and K, and possibly phosphorus (P) were found to be limiting factors according t...

Several okra (Abelmoschus esculentus) cultivars are now available as alternatives to the standards `Clemson Spineless' (open pollinated) and `Annie Oakley II' (hybrid). Based on the results of four trials involving 20 cultivars, `Mita', `Spike', `Green Best' and `North & South' should be added to the list of recommended cultivars for Alabama and Florida. The experimental `SOK 601' should also be included on that list, but on a for trial basis since it was evaluated only at one location. Other cultivars may perform well at specific locations. Differences among cultivars were also found for ease of harvest. `North & South' and `Baby Bubba' were the easiest and most difficult cultivars to harvest, respectively. The economic feasability of selecting a hybrid cultivar over an open-pollinated one and using plasticulture instead of bare ground was also examined in this study. Using hybrid seeds resulted in an average yield increase per harvest of 92 lb/acre (103 kg·ha-1), which exceeded the estimated 75 lb/acre yield (84 kg·ha-1) increase necessary to offset the additional cost of hybrid seeds. For reasons ranging from improved weed control, increased nutrient and water use efficiency, and double cropping, an increasing interest exists to produce okra with plasticulture, instead of bare ground as done traditionally. The average yield increase per harvest due to plasticulture over bare ground production was 196 lb/acre (220 kg·ha-1). Based on this number, it would take three harvests to produce the 540 lb/acre (605 kg·ha-1) yield increase necessary to offset the additional costs due to plasticulture.

Glioblastoma multiforme (GBM) is an end-stage brain tumor of glial origin. Allelic deletions encompassing all or part of chromosome 10q occur frequently in GBMs, indicating that loss of one or more tumor suppressor genes on 10q plays a role in GBM formation. One of these genes is MMAC1 (PTEN), a gene on 10q23 which encodes a dual-specificity protein phosphatase. We carried out a loss of heterozygosity (LOH) analysis of 66 GBM patients using microsatellite markers for 27 loci on 10q. Overall, LOH was detected in 70% of cases, most showing LOH with every informative marker. Eleven patients showed partial 10q deletions, the smallest spanning a 35 cM region distal to D10S187. Sequence analysis of the MMAC1 gene in 45 of these tumors revealed mutations in eleven cases (24%), all with LOH on 10q. None of these mutations was present in normal DNA from the same patients. In addition, we utilized SSCP analysis to test two other candidate genes on 10q: FAS, a cell surface receptor which transduces an apoptotic, cell death signal and MXI1, a transcriptional repressor. The absence of mutations in these genes suggested that FAS and MXI1 are not likely to be tumor suppressor genes physiologically relevant to GBM. These data do support a significant role for MMAC1 in GBM.