scholarly journals Seasonal Abundance and Suppression of Fruit-Piercing MothEudocima phalonia(L.) in a Citrus Orchard in Sarawak

2011 ◽  
Vol 11 ◽  
pp. 2330-2338 ◽  
Author(s):  
Stephen Chan Teck Leong ◽  
Roland Jui Heng Kueh

Seasonal population of the fruit-piercing mothsEudocimaspp. was monitored throughout the citrus growing seasons in a citrus orchard and in site adjacent to secondary forest from July 2007 to June 2009. The moth was detected practically throughout the year with activity lowest during the wet months (September-February) when fruits are still available and while highest during the dry months (May-June) which also coincided with the main fruiting season. The effects of annC24 horticultural mineral oil (HMO) on the citrus fruit damage caused by fruit-piecing moths was also determined. The percent fruit damage was significantly lowest (P≤0.05) in HMO-treated plots (8.4), followed by Dimethoate-treated plots (11.6) and untreated plots (22.5). However, there was no significant difference between HMO and Dimethoate treated plots indicating HMO is effective in reducing percent fruit damage.

2021 ◽  
Vol 14 ◽  
pp. 194008292110103
Author(s):  
Patrick Jules Atagana ◽  
Eric Moïse Bakwo Fils ◽  
Sevilor Kekeunou

We aimed to assess how bats are affected by habitat transformation by comparing bat assemblages in four habitat types: primary forest, secondary forest, cocoa plantations and human habitations in the Dja Biosphere Reserve of southern Cameroon. Bats were sampled in the four habitat types using mist nets. During 126 nights, a total of 413 bats were captured, belonging to four families, 16 genera and 24 species. Ninety three individuals (17 species) were captured in the primary forest, followed by plantations (105 individuals, 14 species), human habitations (159 individuals, 10 species), and secondary forest (55 individuals, eight species). Megaloglossus woermanni was recorded in all the four habitats, and was the most abundant species (105 individuals). The analysis of bat assemblage between habitat types showed a statistically significant difference in species composition. The distribution of the six most abundant species ( Epomops franqueti, Megaloglossus woermanni, Rousettus aegyptiacus, Dohyrina cyclops, Hipposideros cf. caffer and Hipposideros cf. ruber) was influenced by habitat types. Our results suggest that the decrease in species richness observed in disturbed habitats may be due to habitat perturbations of primary forest habitats. Therefore, it is important to examine the effects of habitat conversion at species level, as responses are often species-specific.


2021 ◽  
pp. 1-15
Author(s):  
Sara Bernardo ◽  
Lia-Tânia Dinis ◽  
Nelson Machado ◽  
Ana Barros ◽  
Marta Pitarch-Bielsa ◽  
...  

BACKGROUND: Kaolin particle-film application is a well-known strategy to avoid fruit damage. However, its putative role in balancing berry ripening under a changing climate remains poorly explored. OBJECTIVE: We assessed kaolin treatment effect on several ripening berry components, hormonal balance and oenological parameters of the field-grown Touriga-Franca (TF) and Touriga–Nacional (TN) grapevine varieties at veraison (EL35) and ripening (EL38) during two growing seasons (2017 and 2018). RESULTS: Under the adverse summer conditions (two heatwave events) of 2017, kaolin application increased 211.2 %and 51.4 %the salicylic acid (SA) and abscisic acid (ABA) levels in TF berries at EL38, while no significant differences were observed in TN. Conversely, TF, and TN kaolin treated berries showed lower SA and ABA accumulation in 2018, respectively. Tartaric acid content increased about 17.2 %, and 24.2 %in TF and TN treated berries at stage EL35 in the 2017 growing season. Though kaolin treatment had no consistent effect on anthocyanins accumulation, flavonoids, ortho-diphenols and tannins increased in kaolin treated grapevines in 2017. CONCLUSIONS: This study highlights the key role of climate in triggering ripening related processes and fruit quality potential. Nevertheless, kaolin treated grapevines displayed an improved response to oxidative stress signals by increasing secondary metabolites accumulation in warm vintages. Kaolin application promoted different varietal responses, with a possible ripening delaying effect in TF, reinforcing its efficiency in alleviating severe summer stress impacts.


2014 ◽  
Vol 32 (1) ◽  
pp. 227-232 ◽  
Author(s):  
M.A.P. Oliveira ◽  
U.R. Antuniassi ◽  
E.D. Velini ◽  
R.B. Oliveira ◽  
J.F. Salvador ◽  
...  

The objective of the present study was to analyze the influence of spray mixture volume and flight height on herbicide deposition in aerial applications on pastures. The experimental plots were arranged in a pasture area in the district of Porto Esperidião (Mato Grosso, Brazil). In all of the treatments, the applications contained the herbicides aminopyralid and fluroxypyr (Dominum) at the dose of 2.5 L c.p. ha-1, including the adjuvant mineral oil (Joint Oil) at the dose of 1.0 L and a tracer to determine the deposition by high-performance liquid chromatography (HPLC) (rhodamine at a concentration of 0.6%). The experiment consisted of nine treatments that comprised the combinations of three spray volumes (20, 30 and 50 L ha-1) and three flight heights (10, 30 and 40 m). The results showed that, on average, there was a tendency for larger deposits for the smallest flight heights, with a significant difference between the heights of 10 and 40 m. There was no significant difference among the deposits obtained with the different spray mixture volumes.


2009 ◽  
Vol 57 (4) ◽  
pp. 389-399 ◽  
Author(s):  
J. Nagy

The yield, protein and starch content of Martonvásár maize hybrids belonging to different FAO groups were examined in experiments involving early, optimal and late sowing dates in two different years (drought — 2007, favourable water supplies — 2008) on a calcareous chernozem soil with loam texture at the Látókép Experimental Station of the Centre of Agricultural Sciences and Engineering, University of Debrecen.Sowing date had a significant effect on maize grain yield in the dry year. The grain yields of hybrids with longer growing periods were significantly higher than those with shorter growing periods in both years, but they reacted sensitively to the change in sowing date in the dry year. Due to the rainfall distribution in the growing season, sowing date did not modify the performance of the hybrids in the year with favourable water supplies. Sowing date had a significant effect on the grain protein content in the dry year, with significantly higher values after late sowing than after early or optimal sowing. Averaged over the sowing dates, the protein content of the FAO 200 hybrid was significantly higher in both years than that of hybrids in other FAO groups. In the dry year, the greatest difference in protein content could be observed between the early and late sowing dates for hybrids in all four FAO groups. A negative correlation was found between yield and protein content. Sowing date significantly increased the starch content of maize in the favourable year, with a significant difference between early and late sowing dates.In the dry year higher starch contents were recorded for all the hybrids and for all the sowing dates than in the favourable year. In the dry year, sowing date only caused a significant difference in the starch content in the case of FAO 200 sown at optimal and late sowing dates. In the favourable year, a significant difference was only obtained for the starch content of the FAO 400 hybrid sown at early and late sowing dates. Satisfactory quality can only be achieved if suitable genotypes are grown with appropriate technologies.


Agronomy ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 208 ◽  
Author(s):  
Abdelaziz Nilahyane ◽  
M. Islam ◽  
Abdel Mesbah ◽  
Axel Garcia y Garcia

In water-scarce regions, high yield and improved water use efficiency (WUE) of crops can be obtained if water and nitrogen (N) are properly applied. While water and N have been the subject of research worldwide, studies are needed to advance our understanding on the complexity of their interaction. A field experiment was conducted at the University of Wyoming Powell Research and Extension Center in 2014 and 2015 growing seasons to determine the effect of irrigation water and N on growth, dry matter (DM) yield, and WUE of silage corn (Zea mays L.) grown under on-surface drip irrigation (ODI). The experiment was laid out as a randomized complete block design in split-plot arrangement with three replications. Irrigation was the main treatment and included 100ETc (100% crop evapotranspiration), 80ETc, and 60ETc. Nitrogen was the sub-treatment and included 0, 90, 180, 270, and 360 kg N ha−1 as urea-ammonium-nitrate solution Results showed that irrigation water, N, and application timing significantly affected growth and DM yield, especially at late vegetative and mid reproductive growth stages. At harvest (R4), no significant difference was observed between 180 kg N ha−1 and 270 kg N ha−1 on DM yield and WUE. However, significant differences of DM yield were observed between irrigation treatments, and 100ETc and 80ETc did not differ in WUE. Our findings suggest that 100ETc and 180 kg N ha−1 is the best combination for high yielding corn for silage grown in a semi-arid climate under ODI.


Lubricants ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 100 ◽  
Author(s):  
F. Borras ◽  
Matthijn de Rooij ◽  
Dik Schipper

The use of Environmentally Acceptable Lubricants (EALs) for stern tube lubrication is increasing. Although the machine components of a sailing vessel are designed to operate together with mineral oil-based lubricants, these are being replaced by the less environmentally harmful EALs. Little is known about the rheological performance of EALs in particular at the high shear rates that occur in stern tube seals. In this study, the viscosity and wetting properties of a set of different EALs is analysed and compared to traditional mineral oil-based lubricants using a set of experimental techniques. Some of the EALs present Newtonian behavior whereas other show shear thinning. No significant difference in surface tension was observed between the different lubricants.


2016 ◽  
Vol 46 (5) ◽  
pp. 825-831 ◽  
Author(s):  
Demétrius de Araújo ◽  
Carlos Gilberto Raetano ◽  
Hamilton Humberto Ramos ◽  
Douglas Sampaio Ribeiro da Rocha ◽  
Evandro Pereira Prado ◽  
...  

ABSTRACT: Citrus black spot (CBS) caused by Guignardia citricarpa is one of the most serious Brazilian citrus diseases. This study aims to assess the interference of three application volumes in spray deposition citrus fruit, as well as fruit growth and rainfall effects on spray deposit reduction during the CBS control period. The experiment was carried out in a commercial citrus orchard, with sixteen-year-old trees of the Valencia variety, in Mogi Guaçu, São Paulo State, Brazil. The spray volumes were: 3.5 (1333L ha-1), 4.5 (1714L ha-1) and 8.5 (3238L ha-1) litres per tree, sprayed by an airblast sprayer using fungicides at recommended periods for disease control. The spray deposition quantification and residue was done by spectrophotometry using a copper oxychloride tracer. Samples were collected in three height zones of the tree (top, middle and bottom) and placed between trees on line plantation. Spray depositions were significantly smaller in the first application as a consequence of reduced fruit size. The spray losses on average for each day of rainfall ranged from 4.0 to 5.7%. There was no significant difference between application volumes regarding spray deposition on citrus fruit,which makes possible the reduction of application volumes, however, it is necessary to improve spraying techniques for the top zone of the citrus tree.


Author(s):  
Keli Cristina Dos Santos ◽  
Gentil Carneiro Gabardo ◽  
Jackson Kawakami ◽  
Aline Genú ◽  
Sara Passos ◽  
...  

Aims: Estimate the morphological characteristics of potato genotypes grown with different doses of NPK fertilizer 4-14-8. Study Design: The experiment was conducted in randomized blocks with subdivided plots and three replicates. Place and Duration of Study: The experiment was carried out in the municipality of Guarapuava – PR, Brazil, during the growing seasons of 2013/2014 and 2014/2015. Methodology: In the main plots the doses of 0, 2, 4 and 6 t ha-1 of NPK fertilizer 4-14-8 were arranged and in the subplots the genotypes (Ágata, BRS Camilla and clone C0205). Were evaluated: The leaf area index (LAI), percentage of light absorption, number of tubers, fresh mass of tubers. In the first agricultural year the evaluations were performed at 25 and 45 days after the emergency (DAE) and in the second seasson at 28 and 48 DAE. Interaction between potato genotypes and fertilizer rates for LAI was observed at 45 DAE in 2013/14 and absorbance at 25 DAE in 2013/14. For the seasson 2013/14, the genotypes showed a significant difference for LAI, absorbance, number of tubers and fresh mass of tubers at 25, LAI and fresh mass of tubers at 45 DAE, clone C0205 presented the largest differences for these characteristics. Fertilizer doses did not influence LAI, absorbance at 25 DAE and 45 DAE in 2013/14 and, at 2014/15 at 28 DAE, there was no response for tuber number and LAI, and at 48 DAE for tuber number, absorbance. There was no significant interaction between fertilizer doses and potato plant genotypes for the data on number of primary stems and number of secondary stems in both seassons The genotypes responded to NPK fertilizer doses 4-14-8 for LAI, and clone C0205 presented the best results. The genotypes responded to the light absorption percentage, with C0205 presenting the best results, so that plants with greater leaf area presented greater light absorption. The genotype C0205 presents greater productive capacity when compared to the Agata and Camila genotypes, being evident the greater number and fresh mass of tubers produced.


2018 ◽  
Vol 40 (1) ◽  
Author(s):  
Mateus da Silveira Pasa ◽  
João Felippeto ◽  
Gilberto Nava ◽  
Carina Pereira da Silva ◽  
Alberto Fontanella Brighenti ◽  
...  

Abstract The application of rest breaking agents to overcome the lack of chilling is a common practice in apple orchards in southern Brazil. However, its necessity in areas of greater chilling accumulation, like in the city São Joaquim, Santa Catarina State (SC), has been questioned over the years. The aim of this study was to evaluate the effect of different budbreak promoters, on the performance of ‘Fuji Suprema’ apple trees, in the region of São Joaquim/SC. The study was performed at the Experimental Station of São Joaquim - Santa Catarina Agricultural Research and Extension Agency (EPAGRI), in the growing seasons of 2013/2014, 2014/2015, and 2015/2016. Plant material consisted of 10-year-old ‘Fuji Suprema apple trees grafted on the rootstock ‘M.9’ and arranged in a randomized complete block design with five replicates. Treatments consisted of a nutrient solution containing soluble nitrogen and calcium (NCaS), combined with either calcium nitrate or mineral oil, at different rates; and hydrogen cyanamide combined with mineral oil. The time of application was when buds were between the stages A (dormant bud) and B (swollen bud; silver tip). The influence of treatments on flowering, budbreak, yield components, and fruit quality was assessed. Flowering and fruit quality were little affected by treatments. In the other hand, the budbreak promoters consistently improved axillary budbreak in two out of three seasons.


Author(s):  
M. Dzham

Goal. To study the influence of modern biological and chemical preparations on the development of fungi of the genus Fusariumunder conditions of artificial inoculation. Methods. The efficacy of fungicides was studied in 2018—2019 in the Zhytomyr region, Pulinsky district under the conditions of artificial inoculation on winter wheat of the Bogdan variety. Mixture of conidia of the fusarium fungi (F. graminearum, F. culmorum, F. poae, F. avenaceum) was used for ear inoculation. The plot area was 2 m2 in four replications, the plot placement was randomized. The inoculation of winter wheat ears was carried out at the phase of mass flowering. At the phase of milky-wax maturity, records were taken to determine the spread and development of the disease. The following fungicides were used to protect wheat crops: Folicur BT EC, 1.2 l/ha, Magnello 350 EC, 1.0 l/ ha, Haupsin, 0.2 l/ha, Fitodoktor, 0.05 kg/ha, Alliot 250 EC, 0.5 l/ ha, Bumper Super EC, 1.2 l/ha and mixtures of Magnello 350 EC, 0.75 l/ha + Haupsin 0.2 l/ha, Magnello350 EC, 0.75 l/ha + Fitodoktor, 0.05 kg/ha. Results. The results obtained during the years of investigationsindicate that the used preparations are efficient for the protection of crops from fusarium head blight on winter wheat. However,not all fungicides tested had high enough efficacy. The most effective against the pathogens F.graminearum, F. culmorum, F. poae, F. avenaceumunder conditions of Zhytomyr region were fungicides Folicur BT EC, 1.2 l/ha, Magnello 350 EC, 1.0 l/ha and mixtures of fungicide and biological preparation (Magnello 350 EC, 0.75 l/ ha + Haupsin, 0.2 l/ha). Efficacy of fungicides used against these pathogens ranged from 69.2% to 75.2%. After fungicide application the weight of 1000 grains increased by 7.3—13.6 g. Significant difference between experimental variants and untreated check on 1000 grain weight was noted. With the use of fungicides, the yield increased by 22.3—24.8%. Conclusions. The analysis of the protection against fusarium head blight convinces the need to apply chemical protection measures when weather conditions are favorable for the development of the disease. In the growing seasons of 2018—2019, under conditions of the Zhytomyr region, the most promising and effective against the pathogens F.graminearum, F. culmorum, F. poae, F. avenaceum were fungicides Folicur BT EC, 1.2 l/ha, Magnello 350 EC, 1.0 l/ ha and mixtures of fungicide and biological preparation Magnello 350 EC, 0.75 l/ ha + Haupsin, 0.2 l/ha.


Sign in / Sign up

Export Citation Format

Share Document