The study subject of the experience was Pink Lady apple variety, grafted on M26. The trees were trained as slender spindle system. The distance of plantation was 4.0x1.5 m. The experimental plot was ...placed in the commercial orchard of the enterprise „Terra Vitis” Ltd. founded in 2013. The research was conducted during the period of 2018 year. This study had the aim to determine the efficacy of different agents and doses on the thinning of apple fruits. The following variants were experimented: 1. Control – without treatment; 2. Geramid New, 1.3l/ha; 3. Brevis, 1.1 kg/ha; 4. Brevis, 1.65 kg/ha; 5. Brevis, 2.2 kg/ha. The treatment with the product Geramid New was carried out by spraying, at the fall of 80% of the petals, + 2-3 days, while Brevis treatment was applied when the central fruit in the inflorescence was 10-12 mm in diameter. The number of blossom clusters after thinning, mean fruit weight, yield, average diameter of fruits and size classes based on their diameter were studied during the research. It was established that the good effect of thinning was noticed after application of Brevis, 1.65 kg/ha.
•Thinning is mandatory in peach to improve fruit quality and avoid biennial bearing.•In peach, thinning is currently performed as a strategy with multiple interventions.•Climate changes further ...complicate thinning operations in peach.•New chemical thinners are being developed with promising results.•Research must be funded to avoid the crisis of areas dedicated to peach cultivation.
Peach (Prunus persica L. Batsch) trees need to be thinned in order to guarantee yield of fruits of marketable size and a sufficient return to bloom in the following season. In this fruit crop, however, thinning is often complicated by several endogenous as well as exogenous factors, such as genotype, orchard structure, environmental conditions and agronomic management, and the current thinning methods (manual, mechanical or chemical), taken singularly, present more disadvantages than advantages. Therefore, the only possible option is currently represented by the adoption of a “thinning strategy”, consisting in subsequent interventions at different phenological stages, to finely tune the final fruit load along its physiological evolution. Such strategies must also consider the ongoing climate changes, which further complicates the thinning interventions also due to the lack of Decision Support Systems (DSSs), and the current trends of the global market. The present review takes a picture of the current situation of peach thinning, with a particular focus on the current development of new chemical thinners, and its future perspectives. Some general remarks are made considering the evolution of the global market and the obstacles found in peach research in some of the most traditional peach areas of the world.
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•Chemical thinning of germanium wafers to homogeneously produce < 100 μm thicknesses.•Evaluation of etchant composition to produce mirror-like and pitless surfaces.•Etchant ...formulation was able to produce optoelectronic-grade samples in minutes.•Wafers can be wax-bonded to a removable polypropylene substrate during etching.•Scalable and industrially viable route to improve germanium-based device technology.
Chemical thinning of germanium wafers was carried out in H3PO4:HNO3:HF aqueous solutions, in which etch rates and surface morphology was adjusted through changes in etchant dilution and viscosity. Pitless and smooth surfaces (RMS = 0.42 nm) were obtained at industrially acceptable rates via a diffusion-controlled mechanism. Etchant-resistant wax enabled reversible bonding to a polypropylene substrate, emerging as a potential route for industrial production of thinned germanium optoelectronics.
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Accurate chemical thinning of apple trees requires estimation of their blooming intensity, and determination of the blooming peak date. Performing this task, as of today, requires human experts to be ...present in the orchards for the entire blossom period or extrapolate using a single observation. Since experts are rare and in high demand, there is a need to automate this process. The system presented in this paper is able to estimate the blooming intensity and the blooming peak date from a sequence of tree images, with close-to-human accuracy. For this purpose, a two years dataset was collected in 2014–2015, partially tagged for the flowers location and completely annotated for blooming intensity. Using this dataset, an algorithm was developed and trained with three stages: a visual flower detector based on a deep convolutional neural network, followed by a blooming level estimator, and a peak blooming day finding algorithm. Despite the challenging conditions, the trained detector was able to detect flowers on trees with an Average Precision (AP) score of 0.68, which is on a par with contemporary results of other objects in detection benchmarks. The blooming estimator was based on a linear regression component, which used the number of flowers detected and related statistics to estimate the blooming intensity. The Pearson correlation between the algorithm blooming estimation and human judgments of several experts indicated high agreement levels (0.78–0.93) which were similar to the correlations measured among the human experts. Moreover, the developed estimator was relatively stable across multiple years. The developed peak date finding algorithm identified correctly the orchard’s blooming peak date, which was used to determine the thinning date in the current practice (the entire orchard is thinned in the same day). Experiments testing the algorithm’s ability to find a blooming peak date for each tree independently showed encouraging results, which may lead upon refinement to a more precise practice for tree-specific thinning.
Layered black phosphorus (BP) has been expected to be a promising material for future electronic and optoelectronic applications since its discovery. However, the difficulty in mass fabricating ...layered air-stable BP severely obstructs its potential industry applications. Here, we report a new BP chemical modification method to implement all-solution-based mass production of layered air-stable BP. This method uses the combination of two electron-deficient reagents 2,2,6,6-tetramethylpiperidinyl-N-oxyl (TEMPO) and triphenylcarbenium tetrafluorobor (Ph3CBF4) to accomplish thinning and/or passivation of BP in organic solvent. The field-effect transistor and photodetection devices constructed from the chemically modified BP flakes exhibit enhanced performances with environmental stability up to 4 months. A proof-of-concept BP thin-film transistor fabricated through the all-solution-based exfoliation and modification displays an air-stable and a typical p-type transistor behavior. This all-solution-based method improves the prospects of BP for industry applications.
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The study subject of the experience was RX 1247 pear variety, grafted on BA 29 rootstock. The trees were trained as slender spindle system. The distance of plantation is 4.0x2.0 m. The experimental ...plot was placed in the orchard of „Terra Vitis” Ltd. founded in 2013 year. The research was conducted during the period of 2018 year. This study had the aim to determine the efficacy of Brevis on the chemical thinning of pear fruits. The fol-lowing experimental variants were tested: 1. Control – without treatment; 2. Dirager, 0.35 l/ha; 3. Brevis, 1.1 kg/ha; 4. Brevis, 1.65 kg/ha; 5. Brevis, 2.2 kg/ha. The spray with the products Dirager and with Brevis was performed when the central fruit in the inflorescence was 11.8 mm in diameter (05.05.2018). During the research, the number of fruits, mean fruit weight, crop yield and fruit size classes based on their weight were analyzed. It was established that the good effect of chemical thinning was noticed after application of the product Brevis in dose 1,1 kg/ha.
Solar cells manufactured on top of Ge substrates suffer from inherent drawbacks that hinder or limit their potential. The most deleterious ones are heavy weight, high bulk recombination, lack of ...photon confinement, and an increase of the heat absorption. The use of thinned Ge substrates is herein proposed as a possible solution to the aforementioned challenges. The potential of a thinned Ge subcell inside a standard GaInP/Ga(In)As/Ge triple‐junction solar cell is assessed by simulations, pointing to an optimum thickness around 5–10 μm. This would reduce the weight by more than 90%, whereas the available current for the Ge subcell would decrease only by 5%. In addition, the heat absorption for wavelengths beyond 1600 nm would decrease by more than 85%. The performance of such a device is highly influenced by the front and back surface recombination of the p–n junction. Simulations remark that good back surface passivation is mandatory to avoid losing power generation by thinning the substrate. In contrast, it has been found that front surface recombination lowers the power generation in a similar manner for thin and thick solar cells. Therefore, the benefits of thinning the substrate are not limited by the front surface recombination. Finally, Ge single‐junction solar cells thinned down to 85 μm by wet etching processes are demonstrated. The feasibility of the thinning process is supported by the limited losses measured in the current generation (less than 6%) and generated voltage (4%) for the thinnest solar cell manufactured.
Thinned Ge substrates would decrease the weight of the solar cells and reduce the heat absorption caused by the carrier absorption while still generating enough current for a triple‐junction solar cell. Moreover, the lower bulk recombination would enhance the solar cell performance in the absence of surface recombinations, being the optimum thickness in the range of 5–10 μm. Solar cells thinned down to 85 μm by chemical thinning have been demonstrated, validating the thinning process.
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•Metamitron applied twice at 165 g ha−1 consistently thinned young apple trees.•Effects after double and single application at optimum conditions were similar.•Addition of prohexadione-ca or citric ...acid did not affect the thinning efficacy.
To achieve a high quantity of premium class fruit, chemical thinning is an important component of crop load management in apples. For this purpose, the triazine-type photosynthetic inhibitor metamitron was registered for fruit thinning in Germany. Frequent studies demonstrated consistent thinning effects of metamitron on trees of different apple and pear cultivars. In the present study, the efficacy of metamitron applied at a low concentration (165 g ha−1) was investigated in 2016 and 2017 on young 'RoHo3615' apple trees, planted in 2014. The highest fruit set reduction was achieved when metamitron was applied twice. Single application, in contrast, led to variable results and pointed out the strong dependence of the thinning efficacy of metamitron on favourable weather conditions. Adding citric acid or the growth regulator prohexadione-Ca in combination with ammonium sulphate did not affect the thinning efficacy of metamitron. The fruit quality was high in any treatment and no effects of thinning treatment on fruit colouration or percentage of skin russeting were observed. Consequently, metamitron is an effective fruit thinning agent for young apple trees, which can be additionally used in combination with the mentioned substances, while maintaining a high fruit quality
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Flower or fruitlet thinning is one of the cultural practices used for improving the fruit quality and regulation of yield. The effect of ATS (FloreduX), 6-BA (MaxCel) and metamitron (Brevis) on yield ...and some fruit characteristics of apple trees cv. Šampion/ M.9 T337 was evaluated. Chemical thinning agents were applied alone, as subsequent spraying or as a tank mixture. Due to the possibility of damage to flowers by the announced frosts, a preparation containing sea algae – Goëmar was added in some treatments. Thinning with only MaxCel resulted in an excessive reduction of the total yield expressed in the number of fruits and their mass, but using MaxCel after flower thinning with Floredux gave very good results. The total yield expressed in kg tree -1 was even bigger than in the control, but the share of fruits with diameter above 7.5 mm was much better. The most promising method of thinning apple trees cv. ‘Szampion’ was the use of MaxCel+Brevis, at fruitlets diameter of 10-12 mm. The yield expressed by the number of apples on a tree was much smaller than in the control, but total yield did not differ from the total yield of the control trees. Apples in this treatment were characterised by the highest mass and length, as well as large diameters. In the fruits of this treatment, there was no significant reduction in flesh firmness relative to the control, and they had the highest dry matter content.
A thorough understanding of plant behavior at different growth stages is of paramount importance for fruit quality improvement, the regulation of production periods, and reduced fruit production ...costs. There are as many as three waves of flowering in evergreen pomegranate cultivars – i.e., during the spring, rainy, and autumn seasons. However, for securing enhanced production of superior quality fruits as well as profit to the growers, crop regulation is required. This can be achieved by forcing the tree to rest at a particular stage and by producing abundant blossoming and quality fruits during any one of the three flushes. Observations on phenological phases would help in understanding the dates of specific stages of crop development, which in turn enable the growers to plan, organize, and carry out timely schedules of agronomic practices such as irrigation, fertilization, and crop protection. Therefore, there is a need to evaluate the response of pomegranate under different environmental conditions to identify a suitable flowering season to produce a better quality of fruits with consistent yield, and to enable standardization of management practices for optimum production based on phenological stages.
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