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Effects of prohexadione-calcium (ProCa, 125 and 250 mgL–1) and ProCa + ammonium sulfate (AMS, 500 mgL–1) treatments on vegetative characteristics (shoot growth, branch diameter, trunk cross-sectional area (TCSA), canopy volume, number of flower per cm2, number of fruits per cm2) and quality parameters (fruit size, flesh firmness, color, titratable acidity and soluble solids content (SSC)) of ‘0900 Ziraat’ sweet cherry were investigated in this study. Solutions were sprayed when the shoots were just 10 cm long in 2014 and 2015. As compared to control, in 2015, TCSA decreased only with ProCa treatments (125 and 250 mgL–1) and canopy volume and shoot length decreased with all treatments. On the other hand, number of flower and fruit per cm2 significantly increased with all treatments. While there were not significant differences in fruit size, flesh firmness, color, SSC and titratable acidity values were significantly lower in 250 mgL–1 ProCa and 250 mgL–1 ProCa + AMS treatments. It was concluded that ProCa treatments could be used as an efficient tool for suppression of shoot growth and to increase the number of flower and fruits per cm2 in ‘0900 Ziraat’ sweet cherry cultivar.

Se actualiza la información taxonómica y geográfica de Ochthera para Colombia, un género con especies benéficas, reconocidas por sus hábitos depredadores de insectos pequeños terrestres y larvas de mosquitos. Se incluye el primer registro de Ochthera (O.) pilosa y nuevos datos de distribución para Ochthera (O.) regalis y Ochthera (O.) angustifacies. Se agregan ilustraciones, comentarios de su distribución y mapas.

El presente artículo se centra en el análisis del vocabulario con que se designa al gobernante en las obras De summa temporum uel de origine actibusque gentis Romanorum y De rebus Geticis de Jordanes y la Historia Francorum de Gregorio de Tours. En primer lugar se analizan los términos augustus, augusta, caesar e imperator, denominaciones del gobernante del Imperio Romano, después princeps, que hace refencia tanto al Romano como al de otros pueblos, a continuación rex, regina, que siguen siendo los vocablos con que se nombra a los reyes romanos y, además, designan al máximo mandatario de otros pueblos. Este mismo valor, pero restringido a monarcas de pequeños estados, tienen términos menos frecuentes en época clásica, como regnator y regulus y otros de aparición más tardía como subregulus y regalis. Algunos de estos términos acabaron desapareciendo, pero muchos perviven en las lenguas modernas.

Prohexadione-Ca (ProCa) was applied in an adult walnut orchard of cv. Franquette to test its ability to reduce severity of Xanthomonas arboricola pv. juglandis (Xaj) infection, and the effect on the contents of phenolic compounds in walnut fruits. ProCa was used three times over at 8-10 day interval, starting before the stigmas emergence at 0.125 mg l-1 concentration (treatment R1), and at the stage of brown stigmas at 0.250 mg l-1 concentration (treatment R2). Blight severity was assessed within the orchard at the same time as the husk tissues from symptomatic fruits were sampled for phenolic analyses, which were conducted using HPLC with PDA and MS detection. ProCa caused a significant reduction in Xaj severity regardless of the concentration and the first application date. The induced defence reaction was maintained throughout the season. Within a 15-day interval after the ProCa treatments, the walnut husks showed up to a 14 fold higher content of different phenolics than before fruit maturation. The treated fruits had a higher total phenolic content (TPC), more hydroxycinnamic acids (HC), and flavanols, whilst the contents of flavonols and gallic acid had decreased due to ProCa. The expressed potential of ProCa for triggering the defense mechanisms of walnut through the regulation of phenolic synthesis should be confirmed by additional experiments with the final aim of including this product in a sustainable control against Xaj. [ABSTRACT FROM AUTHOR]

Recently, novel strategies and chemical agents for prophylactic protection against the bacterial (Erwinia amylovora) disease fire blight are being sought. Resistance-inducing compounds, such as prohexadione-Ca represent promising alternatives. Prohexadione-Ca is the active ingredient of the bioregulator Regalis, currently being introduced in several European countries and overseas. Another product used in this study was Biomit Plussz, a leaf fertiliser providing harmonic supply of nutrient elements, the complete supply is assumed to improve the tolerance against diseases. Treatments' effects of both of these products were compared to the effectiveness of treatments with antibiotics repeated twice, three or four times a season. In the years of 2001 and 2002, the effectiveness of both Regalis and Biomit Plussz in reduction of incidence of shoot blight was similar, or proved to be superior to the check treatments consisting of repeated sprayings of antibiotics. Last year (2003) treatments of streptomycin resulted — although within the same magnitude — in a somewhat better control of shoot blight than sprayings with the other compounds. As regards severity of blossom blight, inconsistent results were recorded concerning both Regalis and Biomit Plussz. In general, prohexadione-Ca is less efficient for controlling flower infection by E. amylovora as compared to shoot infections, since successful prophylactic treatments are difficult to carry out early in the season. The highest effectiveness in fire blight management can, therefore, be achieved by using prohexadione-Ca (as preventive protection) in combination with streptomycin or other suitable antibiotics (as curative protection).

Prohexadione-calcium (ProCa) is used routinely in orchards to control vegetative growth and to reduce the shoot blight phase of fire blight. This communication reports on multiple-year applications of ProCa with special emphasis on treatment effects on fruit set, fruit size, and return bloom. Increased fruit set was confirmed from high rates of ProCa above 125 mg·L-1. The increase in fruit set was attributed primarily to a reduction of abscission during June drop rather than an increase in initial set. ProCa decreased fruit weight in some instances. Part of this reduction could be attributed to increased fruit set. However, the large reduction in fruit weight at harvest could only be explained by a direct effect of ProCa when used at high rates. When ProCa was applied as a concentrate spray at 250 mg·L-1, terminal growth was reduced comparable to the application made as a tree row volume dilute spray (Ix). However, fruit set was increased when the spray volume in which ProCa was delivered was reduced to 4x. A range of ProCa rates was used on 'Mutsu'. An initial application rate of 42 mg·L-1 followed by similar subsequent rates controlled growth comparably to higher initial and total rates, yet low rates had no effect on fruit weight or return bloom. Low rates of ProCa appear to be effective at controlling vegetative growth yet appear to have minimal side effects. High rates, especially those intended to reduce fire blight, come with the risk of increased fruit set and reduced fruit size and return bloom. [ABSTRACT FROM AUTHOR]

Prohexadione-calcium (ProCa) has emerged as one of the most important management tools that an orchardist has available to control vegetative growth and to reduce the incidence and severity of fire blight, it has also been implicated in increased fruit set on treated apple trees. This investigation was initiated to confirm the effects of ProCa on fruit set and to evaluate different thinning strategies that might be used to appropriately thin treated trees. ProCa increased fruit set when applied at petal fall at initial rates of 125 or 250 mg·L-1 in three of the four experiments described in this article. Thinners were applied before, at the time of, and after application of ProCa. In all experiments, chemical thinners did not reduce fruit set to the same crop load level on ProCa-treated trees as they did on untreated trees, it was concluded that a different and more aggressive chemical thinning strategy must be used on trees that were treated with ProCa. Fruit size was reduced on ProCa-treated trees. This reduction was usually, but not always, related to increased fruit set. ProCa increased the number of pygmy fruit on 'Delicious' apple trees. [ABSTRACT FROM AUTHOR]

Abstract: During the period 2001–2003 the performance of paclobutrazol, prohexadione-Ca, root pruning, summer pruning and deficit irrigation was studied with respect to a control in a Blanquilla pear orchard. Shoot growth, yield, fruit size, and return bloom were all evaluated. Paclobutrazol was associated with the shortest shoot length and the highest return bloom. Summer pruning and prohexadione-Ca were the strategies that produced the next shortest shoot length; however, summer pruning registered the lowest return bloom and accumulated yield. Prohexadione-Ca did not have any significant negative effect on either return bloom or yield. Root pruning and deficit irrigation produced a slight reduction in shoot length, although these were, respectively, the second and third strategies in relation to return bloom. Before 2001, chlormequat chloride (CCC) was a good tool because it provided good growth control, and increased both return bloom and fruit set. The strategies studied do not present all of these benefits at the same time, but each one contributes with any advantage on growth control, return bloom, fruit set or yield. It seems than the option to optimize growth control, return bloom and yield must be pursued with the integration of several strategies [Copyright &y& Elsevier]

Prohexadione-calcium (Regalis) is a shoot growth retardant that inhibits gibberellins biosynthesis The aim of this study was to evaluate the efficacy of applying Regalis by foliar applications in Passé Crassane pear orchards to reduce tree vigor or shoot growth, to improve the structure of the canopy, to accelerate the earliness of fruit bearing and to control the alternate fruit production. Three different dosages were tested: 50ppm, 100ppm 150ppm. Regalis treatments ranging from 50 to 150 ppm were compared with control, without treatments. The first treatment was applied 7days after petal fall and the others every 10 days after the first treatment. The data was collected at the end of the vegetation period on 10 October. The growth vigor of the shoots and the shoot length of node was significantly difference after the treatment of 150 ppm than the application of 100ppm and 50ppm. The mean number of nodes per shoot percentage was not significantly different between different treatment (50ppm, 100ppm and 150ppm). The length of the shoots for non- treated trees was higher than for treated ones. [ABSTRACT FROM AUTHOR]

Proheaxadione-calcium (ProCa) was applied to 'Spencer' apple trees at rates between 250 to 750 mg·L-1 after harvest but before leaf fall. The following spring terminal growth was reduced linearly from early petal fall through the growing season to leaf fall. ProCa was applied after harvest and before leaf fall at 500 mg·L-1 to 'Spigold' apples. The carryover effect on terminal growth persisted for about 2 weeks after bloom. A combination of 500 and 82.5 mg·L-1 ProCa on 'Spigold' in the fall and spring, respectively, reduced terminal growth greater than the individual treatments for about 3 weeks after petal fall. Recent report have shown that ProCa can induce physiological resistance to fire blight and apple scab when applied near petal fall. These data support the suggestion that ProCa may be used as a fall application and the carryover effects may result in early growth control. Potential benefits of the carry-over effects of ProCa for early-season suppression of fire blight and apple scab are discussed. [ABSTRACT FROM AUTHOR]