Top PDF Application time of chemical thinning with metamitron in ‘Sensação’ peach trees

Application time of chemical thinning with metamitron in ‘Sensação’ peach trees

Application time of chemical thinning with metamitron in ‘Sensação’ peach trees

has intense bloom and exhibits, on average, from 12 to 14 pairs of floral gems every 25cm in length on the branch (Raseira et al., 2014). This condition, associated with good uniformity in plant bloom, may have contributed to make remaining flowers develop fruits. Besides, Figure 2 shows that environmental conditions, regarding temperature, were similar in both years (14-19 °C). Even though ‘Maciel’ peach trees had different behavior from the one in the year of application, they did not exhibit any trend in fruit set in relation to the period in which metamitron was applied (Farias et al., 2019). According to Nava et al. (2009), peach trees usually have high fruit set rates, with the contribution of environmental conditions, such as sunny, mild and dry days during blooming. These authors also state that inadequate climatic conditions, such as temperature, rain and relative humidity, in the blooming period may influence fruit establishment and lead to diseases in flowers.
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Comparison between benzyladenine and metamitron as chemical thinning agents in Gala, Kanzi, Pink Lady and Red Delicious apple cultivars

Comparison between benzyladenine and metamitron as chemical thinning agents in Gala, Kanzi, Pink Lady and Red Delicious apple cultivars

Besides the efforts to standardize application guidelines, there is still some uncertainty in the use of chemical thinning, not only in what substances to use, but when and how to use them. This is mainly because the efficacy of thinning agents is strongly dependent on a complex interaction not only between cultivar, tree vigor, time of application, way of application and environmental conditions (Forshey, 1986; Racskó, 2006; Wouster, 2014) but also between temperature, humidity and radiations levels, which are three very important factors to take into account, not only during the spraying but also in the two following days (Stover and Greene, 2005). According to Forshey (1986) and Stover and Greene (2005), the ideal weather conditions after spraying are mild temperatures and high levels of sunlight and humidity, in opposition for very high and low temperatures and rain, that have negative consequences in the absorption of the compounds. The same authors state that, the referred environmental conditions reduce carbohydrate availability to young fruits, are likely to act synergistically with the thinning agent to induce greater crop load reduction, with the possibility of excessive thinning rates.
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GIBBERELLIC ACID REDUCES FLOWERING AND TIME OF MANUAL THINNING IN ‘MACIEL’ PEACH TREES

GIBBERELLIC ACID REDUCES FLOWERING AND TIME OF MANUAL THINNING IN ‘MACIEL’ PEACH TREES

The large amount of flowers and the high effective peach fruit set (NAVA et al., 2009) result in a load that the plant cannot stand, bearing fruit with low commercial value. In this regard, the thinning of fruit or flowers aims to reduce the plant load, increasing the size and quality of fruits, avoiding the production alternation and maximizing the final value of the product (BYERS et al., 2003; MEITEI et al., 2013). In the peach tree, thinning is usually performed in a manual way and is a delicate operation that requires high demand of manpower, short period for realization and high cost (COSTA; VIZZOTTO, 2000). Thinning in the peach tree represents a third of manpower total cost of the culture (LICHOU et al., 1997), and the practice may take 100 to 150 h ha -1 , depending on the vigor of the plant, age, size, flower production and cultivar (TAHERI et al., 2012). Aiming to replace or reduce the time of hand thinning, alternative studies with chemical thinning are being developed due to the high cost and uncertainty of future availability of manpower in the fruit production system worldwide (MCARTNEY et al., 2012).
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Abscisic acid as a potential chemical thinner for peach

Abscisic acid as a potential chemical thinner for peach

stage 2, and of controls without application. Manual thinning was performed at 42 DAFB. Fruit abscission (%) was determined by the time and after application. At 2, 7, 10, and 15 days after application (DAA), four fruit per replicate were collected from plants for ethylene quantitation. Two fruit were randomly selected  and placed in hermetically sealed 50 mL bottles kept at 25±1°C for 48 hours. At the end of this period, an  aliquot  of  1  mL  of  the  headspace  inside  the  bottles  was collected, using a hypodermic syringe, which was injected into a gas chromatograph Shimadzu GC‑14B,  (Shimadzu, Kyoto, Japan) equipped with a fused silica  capillary column (30 m x 0.25 mm x 0.1 mm) and a flame ionization detector. 
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USE OF METAMITRON AS AN APPLE THINNER

USE OF METAMITRON AS AN APPLE THINNER

Herbicide metamitron is an inhibitor of photosystem II, belonging to triazinone chemical group, which has recently been reported as efficient product in the thinning of apple crops (LAFER, 2010; BASAK, 2011; STERN, 2014), as it affects the photosynthetic apparatus for 7 to 10 days after application, reducing electron transport rates by up to 60% (MCARTNEY; OBERMILLER, 2012). The ‘metamitron’ active principle is effective in the chemical thinning of apple trees when applied at the stage of petal fall until fruit reaches a diameter of up to 18 mm (BASAK, 2011), which effect may be enhanced when associated with other thinners (MCARTNEY; OBERMILLER, 2012; GREENE, 2014). The decrease in plant fructification as well as the increase in mean fresh fruit weight is proportional to the increase in the metamitron concentration applied (BRUNNER, 2014; GREENE, 2014; STERN, 2014). However, MCartney and Obermiller (2014) point out the possibility of excessive fruit drop depending on the concentration and application stage of this plant growth regulator. In addition, the effect of chemical thinners is dependent on the interaction between genotype and climatic conditions, and should therefore be tested in each
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Chemical attributes of soil under cassava wastewater application in Marandugrass cultivation

Chemical attributes of soil under cassava wastewater application in Marandugrass cultivation

The use of agroindustry residues as alternative sources of fertilizers directly influences the chemical characteristics of soils and can alter pH, electrical conductivity, nutrient concentration, among others, allowing the increase of productivity. However, if this residue is improperly used or applied in areas with a risk of damage to the environment, it can cause problems, such as: reduction of dissolved oxygen and eutrophication of water bodies, death of aquatic fauna and animals that consume water with excess hydrocyanic gas (Campos et al., 2006).
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Chemical composition of corn and sorghum grains cultivated in oxisol with different application methods and doses of zinc

Chemical composition of corn and sorghum grains cultivated in oxisol with different application methods and doses of zinc

It is possible that low quality cereal grains occur because the main goal of plant breeding programs has been to increase yield during the last decades (Peleg et al., 2008). However, the nutritional composition is equally important and has been largely neglected in such programs, especially concerning micronutrient contents (Cakmak, 2002). Thus, future studies assessing more eficient Zn application methods to promote Zn uptake in plants and to maximize the accumulation of this micronutrient in grains must be developed (Camak, 2008).

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Net mineralization nitrogen and soil chemical changes with application of organic wastes with ‘Fermented Bokashi Compost’

Net mineralization nitrogen and soil chemical changes with application of organic wastes with ‘Fermented Bokashi Compost’

Only small and often contradictory effects of the application of EM preparations on crop yields and plant development have been reported (KHALIQ et al., 2006; OKORSKI et al., 2008; VAN VLIET et al., 2006). EM-applications have also been found to have no effect (KHALIQ et al., 2006; VAN VLIET et al., 2006). Similar results were found by Schenck zu Schweinsberg-Mickan and Müller (2009) to N mineralization and microbial biomass C and N in soil without amendments and with application of wheat straw and coarse meal of yellow lupins. Few effects have been observed related to the EM carrier substrate molasses. Okorski and Majchrzak (2007) observed the highest soil fungal diversity when EM was applied together with pesticides in a field experiment planted with peas.
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Peach palm flour (Bactris gasipae KUNTH): potential application in the food industry

Peach palm flour (Bactris gasipae KUNTH): potential application in the food industry

the granules undergo gelling, the paste temperature indicates the temperature at which viscosity increases during the heating period (Singh et al., 2011). Ot can be said that the flours produce viscous pastes regardless of the variety, which increase their potential industrial application since they all have the same gelling characteristics. Dverall, the gelling temperature of the starches present in roots and tubers such as potato (58-65 °C) and cassava (52-65 °C) is slightly lower than for starches from cereals such as corn (62-80 °C) and wheat (59-85 °C) (Singh et al., 2011). All values described for the other raw materials are below the ones found for peach palm flour, which is important to suggest possible industrial applications since heating with excess water causes irreversible swelling of starch granules and makes them too sensitive to mechanical and thermal stress. Since peach palm flours have high gelling temperature, they may be used in products that need long processing under high temperature and constant stirring such as sauces (Adebowale et al., 2005).
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Time-frequency Representations Application in Psychological Testing

Time-frequency Representations Application in Psychological Testing

The signal presented in figure 3 is similar to a signal that is obtained using other finger movement tracking methods. Its amplitude corresponds to the spatial amplitude of the finger movement, and its frequency shows the tapping speed. The obtained signal from the low pass filter was then used to generate a time- frequency representation. A Hamming window function used to calculate the time-frequency representation. Other windowing functions provided similar results. Since low frequency components were the ones that were important, a long window function was used, this way improving low frequency resolution. The Short time Fourier representation of the low-pass filtered signal is presented in figure 4, where it is obvious that the signal has a frequency of about 3 Hz, clearly visible in the time-frequency plane. The use of a time-frequency representation has the advantage of having both the time and frequency information available and also the intensity of the signal’s energy is related to its amplitude. The representation in figure 4 is also an image that can be used to compare it with previously recorded finger tapping patterns. Maybe some pattern recognition algorithms [7] could be used to develop an automatic diagnostic system, where the time-frequency representation can be compared to previously recorded ones corresponding to the subject’s age and gender. Any change of the patterns in the time-frequency plane could provide useful information about motor function problems or brain damage. Also, a time-frequency representation is very useful when there are changes of the signals frequency. These changes in frequency can occur during the test for instance when an external stimulus (optical acoustical etc.) is applied to the subject. To test if the frequency changes can be observed in the time-frequency plane, a signal was generated, where a deliberate change in the finger tapping frequency occurred. A time plot of this test signal is presented in figure 5, the change in tapping frequency being observable in the middle of the waveform.
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Application of bayesian additive regression trees in the development of credit scoring models in Brazil

Application of bayesian additive regression trees in the development of credit scoring models in Brazil

The BART method can easily detect and infer reduced models in problems with a large number of variables and for samples with a small number of observations (Chipman et al., 2010). This method of selection of variables is less effective when the number of trees is very high because it tends to mix important predictor variables with those that are not relevant. Bleich et al. (2014) proposed a variable selection model based on BART that uses as a criterion the proportion of times that the variable was used as a rule of segregation of a new branch of the various trees divided by the model’s total number of branches, that is, it selects those variables that appear more frequently in the adjusted sum of trees model. The bartMachine package provided by the R software implements this procedure.
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Flowering period and fruit quality of peach trees selections and cultivars in the metropolitan region of Curitiba

Flowering period and fruit quality of peach trees selections and cultivars in the metropolitan region of Curitiba

The average fruit weight was less than 60g for most of the materials tested (Table 2), being classified within the caliber 3 (51-56 mm) and 2 (45-51 mm) according to the São Paulo program for the improvement of trade patterns and fresh produce packaging. Fruit size, considering the caliber and diameter, is the factor that determines the price (ALMEIDA; DURIGAN, 2006). Production, an important parameter for the future recommendation of cultivars, was not evaluated in the present study due to damages and the low number of fruits mainly in the 2014/15 crop, in which ‘Planalto’, ‘Galaxy’ ‘Early Gold’ and ‘Cascata 1505’ produced less than 10 fruits/plant.
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Phosphorus application for the chemical immobilization of cadmium in contaminated soil.

Phosphorus application for the chemical immobilization of cadmium in contaminated soil.

Comparando-se teores obtidos com os diferentes extratores químicos observa-se que os maiores valores foram com Mehlich-1, que foi quase 3 vezes superior aos do DTPA, ao contrário[r]

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Enhancement of Hevea brasiliensis properties through chemical application

Enhancement of Hevea brasiliensis properties through chemical application

Nevertheless, no bleaching method for solid wood has been developed that could be adapted to use on an industrial scale. Information on how bleaching changes the physical properties of solid wood as well as its mechanical strength properties is still lacking. The current bleaching technique only involved surface treatment of timber. However, discolouration and sap-stain marks in rubberwood are normally not skin deep, but penetrate throughout the cross-section of the wood block. Thus, a bleaching process whereby the bleaching agent is allowed to penetrate deep into the timber is needed, and this could be achieved through the application of vacuum-pressure treatment. The production of creamy-white colour wood coupled with better working qualities will definitely ensure strong continuous demand for rubberwood by the local wood-based industries in the future.
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Mapping of the time available for application of pesticides in the state of Paraná, Brazil

Mapping of the time available for application of pesticides in the state of Paraná, Brazil

The variographic analysis (Table 2) revealed that all months presented spatial dependence with the fitting of variograms to the spherical model, with a minimum range of 79,792.82 m (August) and maximum of 179,990.49 m (October). Several studies indicate this model is best adapted to describe the behavior of the variograms of soil attributes and of the different slope gradients and relief shapes (Trangmar, Yost, & Uehara, 1985; Sanchez, Marques Júnior, Pereira, & Souza, 2005; Lima, Oliveira, & Silva, 2012). The variogram shows the measure of the degree of spatial dependence among samples along a specific support (Landim, 2006), that is, the zone of influence or distance around a station to perform the mapping.
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Application of time shift for nonlinear damping characteristic identification

Application of time shift for nonlinear damping characteristic identification

The characteristic of damping un-mount hydro-pneumatic strut indicated on indicatory stand. Characteristic presented on figure 3 has been separately polynomials approximation for compression and extension. The indentify technical condition strut mount in suspension and excitation to vibrations by the high force excitatory. Amplitude displacement of vibrations was constant, equal to 6 [mm]. Regulation length of time excitation cycles are possibility by frequency converter in control system. Recording signals: vibrations accelerations of sprung mass in point of fix hydro-pneumatic strut and relative displacement wheel and bodies. The example of those signals presented on fig. 4 and 5.
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Application of time-series analysis for prediction of molding sand properties in production cycle

Application of time-series analysis for prediction of molding sand properties in production cycle

Time-series analysis is characterized, as a data mining tool which facilitates understanding nature of manufacturing processes and permits prediction of future values of the process parameters or production results on the basis of the past data, recorded in regular intervals. The main methods and problems of the time-series analysis are presented. The authors’ research results, based on green molding sand proper- ties data collected in a foundry with Disamatic molding line, are presented. The work was aimed at finding optimal settings and models of the time-series analysis for that data as well as detection of possible periodicities appearing in the sand properties. It is concluded that although the time-series analysis requires individual approach to each particular problem, some general recommendations can be also formulated. It can be a useful tool for analysis and predictions of outcomes of foundry processes.
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Occurrence and damage caused by Grapholita molesta (Busck) (Lepidoptera: Tortricidae) on peach trees, in Caldas, MG.

Occurrence and damage caused by Grapholita molesta (Busck) (Lepidoptera: Tortricidae) on peach trees, in Caldas, MG.

ABSTRACT- This work was carried out to evaluate the damages caused by Grapholita molesta (Busck) in twigs and fruits of peach trees (Prunus persicae) in Caldas, MG, during the growing seasons of 1995/96 and 1996/97. Fruits and twigs from three branches of fifteen plants were examined every 15 days. A great variation in the percentage of twigs damage was obtained throughout each season, especially in the second year, when a peak was observed in the end of January. The averages of the porcentage of damage were estimated in 22,9% and 19,4% in 1995/96 and 1996/97, respectively. The total incidence in fruits was 28,1% during the first year and 21,6% during the second year with peaks well definided in the end of October and beginning of November of 1995/96. KEY WORDS: Insecta, oriental fruit moth, yield loss, Prunus persicae.
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Treatment of industrial wastewater: application of chemical and biological processes

Treatment of industrial wastewater: application of chemical and biological processes

Toxicity evolution during photocatalytic experiments was analyzed by respirometry using a BMT Respirometer (SURCIS, S.L), provided with an oxygen probe (Hamilton). The respirometer was loaded with the required amount of activated sludge (1000 mL, according to the manufacturer specifications) taken from a conventional municipal wastewater treatment plant. Afterwards, in order to inhibit the nitrification process and measure the sample effect only on the heterotrophic bacteria, 3 mg of N-allylthiourea per gram of volatile suspended solids (VSS) was added to the activated sludge half an hour before the experiments. Continuous aeration and agitation were applied on the respirometer to attain air saturation conditions. Temperature was maintained at 20° C during the experiment. Samples were previously adjusted to pH 6.5–7.5 and filtered. The toxicity of the wastewater was evaluated by comparing the bacterial activity in two assays: one containing the sludge and 50 mL of distilled water with a biodegradable substrate (reference) and the other containing the sludge and 50 mL of the target sample with the same biodegradable substrate. The substrate used in both cases was sodium acetate (0.5 g/g VSS). In both cases, the tests were extended until the biomass reached the maximum respiration rate (Rs max ) and the inhibition
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Changes in chemical properties of distrophic Red Latosol as result of swine wastewater application

Changes in chemical properties of distrophic Red Latosol as result of swine wastewater application

application were not statistically different at 0.05 level of probability. Although, after treatment application there were statistical differences of Al values in the 0-5 cm layer and the 20-40 cm layer when using the Tukey test at 0.05 probability level. However, Al concentration reduced at all layers (Figure 4A) corroborating results obtained by Bosco et al. (2008), who observed a decrease in aluminum concentration in the 0-30 and 30-60 cm layers when applying SW. For the second season as compared to the first, Al concentration in soil increased, 0.177 cmol c dm -3 , which is consistent with soil pH reduction from the
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