scholarly journals Naphthaleneacetic Acid, Ethephon, and Gibberellin A4 + A7 Have Variable Effects on Flesh Firmness and Return Bloom of Apple

2007 ◽  
Vol 17 (1) ◽  
pp. 32-38 ◽  
Author(s):  
Steven McArtney ◽  
Dick Unrath ◽  
J.D. Obermiller ◽  
Ann Green

Experiments were conducted in commercial apple (Malus ×domestica) orchards in the southeastern U.S. between 1998 and 2006 with the primary objective of evaluating the effects of naphthaleneacetic acid (NAA) and ethephon on return bloom. NAA increased return bloom in six of 10 experiments, whereas ethephon increased return bloom in four of seven experiments. Four biweekly applications of 5 ppm NAA during June and July (early summer NAA) increased return bloom more consistently than fewer applications. Four weekly preharvest applications of 5 ppm NAA increased return bloom of ‘Delicious’ and ‘Golden Delicious’ as effectively as early summer applications. Combining NAA and ethephon in early summer sprays did not consistently increase return bloom compared with either material alone. The flower cluster density of ‘Golden Delicious’ in the year of treatment had a negative effect on return bloom that was more pronounced on control trees than trees sprayed 5 weeks after bloom with 444 ppm ethephon (48 fl oz/acre Ethrel). Combining four early summer sprays of 316 ppm ethephon (24 fl oz/acre Ethrel) with 15 ppm gibberellin A4 + A7 (GA4+7) increased return bloom of ‘Cameo’ but had no effect on return bloom of ‘Mutsu’ or ‘Golden Delicious’. Growth regulator treatments did not have a consistent effect on fruit firmness in the year of treatment. Naphthaleneacetic acid or ethephon treatments in the on year of a biennial bearing cycle can promote return bloom of apple spurs. However, the positive effect on return bloom may be minimal in cultivars with a strong natural tendency toward biennial bearing or when bloom or initial fruit set are heavy in the year of treatment.

HortScience ◽  
2013 ◽  
Vol 48 (6) ◽  
pp. 742-746 ◽  
Author(s):  
Steven McArtney ◽  
Duane Greene ◽  
Tory Schmidt ◽  
Rongcai Yuan

‘Golden Delicious’ and ‘York Imperial’ are apple cultivars that are prone to develop a biennial bearing habit. A successful chemical thinning program with carbaryl plus 6-benzyladenine applied at the 10-mm fruit diameter stage reduced cropload and increased return bloom of ‘York Imperial’, although the improvement in return bloom resulting from chemical thinning was insufficient to ensure a commercial cropload in the year after treatment (fewer than 10% of spurs developing flowers). A chemical thinning program with multiple applications of a naphthaleneacetic acid (NAA) and ethephon mixture during the period from 36 to 73 days after bloom increased return bloom of ‘York Imperial’ trees to commercially acceptable levels (25% or greater of spurs flowering). NAA applied during the period from 50 to 100 days after bloom (summer NAA program) or from 110 to 140 days after bloom (preharvest NAA program) increased return bloom of ‘Golden Delicious’. When aminoethoxyvinylglycine (AVG) was included with the first NAA spray in a summer program, the efficacy was reduced, indicating that ethylene may be partly involved in the florigenic activity of NAA. Dissection of ‘Golden Delicious’ buds sampled from three locations (Asheville, NC; Amherst, MA; Wenatchee, WA) at ≈14-day intervals beginning 50 days after bloom indicated that the time of floral transition (doming of the meristem apex) occurred during the period from 65 to 105 days after bloom at each location. Thus, NAA applications in a summer program for return bloom coincided with the period when floral determination normally occurred. Preharvest NAA programs effectively promoted return bloom in the experiments where a summer NAA program was also effective. These responses indicate that NAA can trigger floral development within vegetative buds relatively late in the summer and outside of the time period when it is generally believed possible to influence flower bud formation.


2019 ◽  
Vol 99 (4) ◽  
pp. 444-459
Author(s):  
John A. Cline

‘Honeycrisp’ apple trees are highly prone to biennial bearing and predisposed to bitter pit. The hypothesis that tank mix sprays of ethephon (ETH), naphthaleneacetic acid (NAA), and 1-aminocyclopropane carboxylic acid (ACC) combined with calcium chloride (CaCl2) can mitigate these production problems was tested in a 3-yr study. Mature ‘Honeycrisp’ trees were treated with either three or six summer applications of 150 mg L−1 ETH or 5 mg L−1 NAA, all tank-mixed with and without CaCl2, or two or five applications of 150 mg L−1 ACC (without CaCl2). Treatments were applied at 10-d intervals and initiated between 21 and 26 June. All treatments had little effect on enhancing return bloom of ‘Honeycrisp’. NAA, ETH, and CaCl2 all influenced fruit maturity and quality at harvest to varying degrees and across years. Fruit treated with NAA were firmer compared with untreated fruit in 2 out of 3 yr, whereas overall, fruit treated with six sprays of ETH had lower fruit firmness and were more mature. NAA had less influence on fruit quality attributes at harvest than did ETH, and decreased pre-harvest fruit drop (PFD). PFD increased with ETH in 1 out of 2 yr, whereas ACC and NAA both decreased PFD in 1 out of 2 yr. Overall, ETH and NAA, with or without CaCl2, had significant but inconsistent effects on fruit quality and maturity, all dependent on the year and number of applications. Adding CaCl2 decreased fruit firmness in 2 out of 3 yr.


2011 ◽  
Vol 33 (No. 4) ◽  
pp. 131-139 ◽  
Author(s):  
J. Blažek ◽  
J. Křelinová

 In an orchard trial that was established in the spring of 1999 on M 9 rootstock at the spacing of 4 × 1 m, eleven new apple cultivars bred in Holovousy (Angold, Julia, Nabella, Primadela, Produkta, Resista, Rubinstep, Rucla, Selena, Vysočina and Zuzana) were evaluated in comparison with three standard varieties (Gala, Golden Delicious and Jonagold) and another two with resistance to scab (Rosana and Topaz). In the first three years, the incidence of scab and mildew was evaluated under limited chemical protection. In 2000–2005 on each of 10 randomly selected trees of each cultivar, the time of flowering and optimum harvest ripening were recorded, flower set and fruit sets were rated, yield per tree and weight of 10 fruit samples were measured. Trunk diameter was measured between 2002 and 2005. The early summer apple Julia had the healthiest state and it was recommended for organic growing. Selena was the most precocious, the least vigorous and had the highest crop efficiency. The highest annual yields per tree were recorded with Produkta, but this cultivar had the highest proportion of trees with biennial bearing. Primadela achieved the highest cumulative yields, whereas Angold brought the largest fruits on average. With the obtained results, the evaluated cultivars were characterised by some important features or recommendations for growers.  


1999 ◽  
Vol 89 (5) ◽  
pp. 455-463 ◽  
Author(s):  
D.A. Maelzer ◽  
M.P. Zalucki

AbstractRegression analyses of a long series of light-trap catches at Narrabri, Australia, were used to describe the seasonal dynamics of Helicoverpa armigera (Hübner). The size of the second generation was significantly related to the size of the first generation, to winter rainfall, which had a positive effect, and to spring rainfall which had a negative effect. These variables accounted for up to 96% of the variation in size of the second generation from year to year. Rainfall and crop hosts were also important for the size of the third generation. The area and tonnage of many potential host crops were significantly correlated with winter rain. When winter rain was omitted from the analysis, the sizes of both the second and third generations could be expressed as a function of the size of the previous generation and of the areas planted to lucerne, sorghum and maize. Lucerne and maize always had positive coefficients and sorghum a negative one. We extended our analysis to catches of H. punctigera (Wallengren), which declines in abundance after the second generation. Winter rain had a positive effect on the sizes of the second and third generations, and rain in spring or early summer had a negative effect. Only the area grown to lucerne had a positive effect on abundance. Forecasts of pest levels from a few months to a few weeks in advance are discussed, along with the improved understanding of the seasonal dynamics of both species and the significance of crops in the management of insecticide resistance for H. armigera.


1991 ◽  
Vol 116 (3) ◽  
pp. 446-449 ◽  
Author(s):  
Joann M. McLaughlin ◽  
Duane W. Greene

Fruit-bearing limbs of five apple (Malus domestics Borkh.) cultivars varying in degree of biennial bearing were either unsprayed or received five repeat applications of BA at 50 mg·liter-1 with daminozide at 2000 mg·liter-1. BA and daminozide increased early appendage formation of potential flower buds, but this increase was sustained only on `Early McIntosh' and `Baldwin'. BA and daminozide increased return bloom on all treated limbs, with the exception of `Early McIntosh'. The annually bearing cultivars McIntosh and Delicious initiated 20 appendages before the formation of floral parts, while the biennially bearing cultivars Golden Delicious, Baldwin, and Early McIntosh initiated 19, 18, and 22 appendages, respectively. Flower removal before bloom increased appendage formation on the biennial cultivar Baldwin but not on the annual cultivar Delicious. Chemical names used: N -(phenylmethyl) -1 H-purine-6-arnine (BA); butanedioic acid mono(2,2-dimethyihydrazide) (daminozide).


HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 983A-983
Author(s):  
Steven J. McArtney ◽  
Dick Unrath

Experiments were carried out in the southeastern United States between 1998 and 2006 to evaluate the potential for applications of NAA, Ethrel, or both, in the on-year of a biennial bearing cycle to increase return bloom in apple. Four bi-weekly applications of 5 ppm NAA beginning in mid June (summer NAA) increased return bloom, measured as the percentage of floral spurs in the year after treatment. The level of return bloom on trees receiving a summer NAA program was more than 2-fold higher than on untreated control trees, averaged across seven different experiments. Four applications of 5 ppm NAA at weekly intervals leading up to harvest (August/September) increased return bloom also. Combining 150 ppm Ethrel with summer NAA sprays resulted in an additive effect on return bloom compared to NAA or Ethrel alone. The effect of flower cluster density on return bloom the following year was more negative on control trees than it was on trees sprayed with Ethrel in the previous year. Treatment effects on fruit maturity at harvest were generally neutral, although flesh firmness was reduced in some experiments. NAA or Ethrel sprays in the on-year of a biennial bearing cycle may provide a strategy for achieving more consistent flowering and cropping in apple.


2013 ◽  
Vol 34 (3) ◽  
pp. 159-169 ◽  
Author(s):  
Sevtap Cinan ◽  
Aslı Doğan

This research is new in its attempt to take future time orientation, morningness orientation, and prospective memory as measures of mental prospection, and to examine a three-factor model that assumes working memory, mental prospection, and cognitive insight are independent but related higher-order cognitive constructs by using confirmatory factor analysis (CFA). The three-factor model produced a good fit to the data. An alternative one-factor model was tested and rejected. The results suggest that working memory and cognitive insight are distinguishable, related constructs, and that both are distinct from, but negatively associated with, mental prospection. In addition, structural equation modeling (SEM) showed that working memory had a strong positive effect on cognitive insight and a moderate negative effect on mental prospection.


2020 ◽  
Vol 3 (2) ◽  
pp. 93-108
Author(s):  
Annisa Siti Fathonah ◽  
Dadang Hermawan

This study aims to determine and analyze how much influence the bank's internal factors such as Equity, Operational Costs per Operating Income (BOPO), Financing Deposit to Ratio (FDR), Non Performing Financing (NPF) as a mediator and external or macroeconomic factors namely inflation and Gross Domestic Product (GDP) on profitability represented by Return on Assets (ROA) at Bank Muamalat Indonesia for the period 2008-2018. The data used in this research are secondary data obtained from the publication of quarterly financial statements from 2008 to quarter 2 of 2018. The method that used in this research is path analysis with SPSS 20.0 as the analytical tool. The results of the study partially test the hypothesis (t-test), in substructure I shows that the capital variable has a significant negative effect on NPF, BOPO and inflation has a significant positive effect on NPF, FDR and GDP do not significantly influence NPF at Bank Muamalat Indonesia. In substructure II partially, Capital, BOPO, significant negative effect on ROA, FDR and NPF has a significant positive effect on ROA, Inflation and GDP does not significantly influence ROA while simultaneously significantly influencing ROA. Based on the sobel test, capital has a significant effect on ROA through NPF, BOPO has a significant effect on ROA through NPF, FDR has a significant effect on ROA through NPF, Inflation has a significant effect on ROA through NPF, while GDP has no significant effect on ROA through NPF.


2020 ◽  
Vol 2 (1) ◽  
pp. 60-79
Author(s):  
Wayan Arya Paramarta ◽  
Ni Putu Kurnia Darmayanti

The aims of this study was to explain the effect of employee engagement and work stress on job satisfaction and turnover intention at Aman Villas Nusa Dua-Bali. The type of data used in this study is qualitative and quantitative data, with data sources namely primary and secondary data. Data collection method is interview, distributing questionnaires to respondents and library research, while the data analysis technique used Smart PLS 3.2.8. The results of this study showed that employee engagement had a positive effect and significant on job satisfaction, work stress had a negative effect but not significant on job satisfaction, employee engagement had a negative effect and significant on turnover intention, work stress had a positive effect and significant on turnover intention, job satisfaction had a negative effect but not significant on turnover intention, employee engagement had a positive effect but not significant on turnover intention trough job satisfaction, work stress had a positive effect but not significant on turnover intention trough job satisfaction at Aman Villas Nusa Dua-Bali.


2019 ◽  
Vol 2 (3) ◽  
pp. 553-561
Author(s):  
Novian Hangga Prakosa ◽  
Fafurida Fafurida

The purposes of this research are to identify the influence of travel cost, income, distance, access, facilities, natural beautiness, and age on the number of individual visits to Curug Silawe and to estimate the economic value of Curug Silawe through individual travel cost method. The population in this study are tourists that visited Curug Silawe with sample of 98 respondents taken by the quota accidental sampling technique. The data collection method used are literature study and questionnaire. The analysis tool used are OLS linear regression and economic value estimation. The results showed the variables that influence the number of individual visits to Curug Silawe are income, distance and age. Income and age has a positive effect. While distance has a negative effect. The economic value of Curug Silawe reached IDR 1,109,930,140.48 per year. This value is obtained from consumer surplus obtained per individual per year of IDR 308,656.88. Tujuan dari penelitian ini adalah untuk mengidentifikasi pengaruh biaya perjalanan, pendapatan, jarak, akses, fasilitas, keindahan alam, dan usia pada jumlah kunjungan individu ke Curug Silawe dan untuk memperkirakan nilai ekonomi Curug Silawe melalui metode biaya perjalanan individu . Populasi dalam penelitian ini adalah wisatawan yang berkunjung ke Curug Silawe dengan sampel 98 responden yang diambil dengan teknik quota accidental sampling. Metode pengumpulan data yang digunakan adalah studi literatur dan kuesioner. Alat analisis yang digunakan adalah regresi linear OLS dan estimasi nilai ekonomi. Hasil penelitian menunjukkan variabel yang mempengaruhi jumlah kunjungan individu ke Curug Silawe adalah pendapatan, jarak dan usia. Penghasilan dan usia memiliki efek positif. Sedangkan jarak memiliki efek negatif. Nilai ekonomi Curug Silawe mencapai Rp1.109.930.140,48 per tahun. Nilai ini diperoleh dari surplus konsumen yang diperoleh per individu per tahun sebesar Rp308.656,88.


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