scholarly journals Disease progress of apple scab caused by Venturia inaequalis in environmentally friendly growing systems

2000 ◽  
Vol 6 (4) ◽  
Author(s):  
I. J. Holb
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Venturia Inaequalis ◽  
Disease Incidence ◽  
Linear Regression Analysis ◽  
Apple Scab ◽  
Integrated System ◽  
Organic System ◽  
Disease Progress ◽  
Leaf Disease

Progression of apple scab epidemic in six apple cultivars, including two current and susceptible (Gala Must, Elstar), two old (Egri Piros, Darusóvári), and two resistant cultivars (Relinda, Releika), were described and analysed in a two-year-study, in two environmental-friendly growing systems (organic and integrated). Curves of disease progress, linear regression analysis of transformed disease incidence data and Area Under Disease Progress Curves (AUDPC) were used to characterise the epidemic processes of the selected cultivars. Cumulative disease progress curves showed continuous but asymmetrical scab development on the moderate or highly susceptible cultivars Gala Must, Elstar and Egri Piros, and on the tolerant or resistant cultivar Darusóvári and Relinda, in both systems. The cultivar Releika showed no symptoms either on fruit or leaf. In linear regression analysis, the best linearisation was given by logistic transformation. Adequate parameters leaf disease incidence rate, of obtained from a regression equation, were higher in the organic system than in the integrated system. Values of AUDPC showed great differences in leaf disease incidences among cultivars and between growing systems. AUDPC gave more differences for comparison of progresses of disease epidemic than growth rate of disease in different systems of disease control. Moreover, the obtained results were compared with similar studies on different pathosystems, and biological interpretations of the analyses are discussed below.

scholarly journals Effect of Production System and Pruning on Temporal Development of Cercospora depazeoides and on Berry Yield in Black Elderberry Orchards

Plant Disease ◽  
2009 ◽  
Vol 93 (6) ◽  
pp. 625-631 ◽  
Author(s):  
I. J. Holb ◽  
J. M. Gáll ◽  
B. Fodor
Keyword(s):  
Leaf Spot ◽  
Production Systems ◽  
Disease Incidence ◽  
Organic Production ◽  
Integrated System ◽  
Disease Development ◽  
Temporal Development ◽  
Cercospora Leaf Spot ◽  
Organic System ◽  
Disease Progress

In a 2-year study, the temporal development of Cercospora leaf spot (Cercospora depazeoides) and berry yield were evaluated in two production systems (integrated and organic) and in two winter pruning treatments (trees pruned to four and eight scaffolds) in two black elderberry (Sambucus nigra) orchards in Hungary. Under organic production, leaf spot onset occurred 2 to 4 weeks earlier (mid- and late July) in both years and both orchards compared with the integrated program. Disease then continuously progressed until the final assessment date (late September) in both years, reaching a maximum final disease incidence of 15.9% in the integrated system and of 38.2% in the organic system. In general, disease progress after late August was greater on trees pruned to eight scaffolds than on trees pruned to four scaffolds in both production systems. Both final disease incidence and area under the disease progress curves (AUDPC) were significantly lower (P < 0.001) in the integrated treatments compared with organic ones. Across all treatments, both disease measures were significantly (P < 0.05) lower on trees pruned to four scaffolds compared with trees pruned to eight scaffolds. However, when the effect of pruning on final disease incidence and AUDPC was analyzed separately for integrated and organic systems, pruning caused uniformly significant differences in disease development only for the organic system. Berry yield was significantly higher (P < 0.05) in the integrated system compared with the organic system, but pruning showed no significant effect on yield. Overall, pruning to four scaffolds resulted in consistently lower disease development in organic production compared to integrated. Thus, winter pruning may be useful as a Cercospora leaf spot management practice in organic elderberry orchards.

scholarly journals Overexpression of the CYP51A1 Gene and Repeated Elements are Associated with Differential Sensitivity to DMI Fungicides in Venturia inaequalis

2016 ◽  
Vol 106 (6) ◽  
pp. 562-571 ◽  
Author(s):  
Sara M. Villani ◽  
Jon Hulvey ◽  
Jean-Michel Hily ◽  
Kerik D. Cox
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Illumina Sequencing ◽  
Venturia Inaequalis ◽  
Linear Regression Analysis ◽  
Differential Sensitivity ◽  
Transcriptional Enhancer ◽  
Relative Growth ◽  
Dmi Fungicides ◽  
Demethylation Inhibitor

The involvement of overexpression of the CYP51A1 gene in Venturia inaequalis was investigated for isolates exhibiting differential sensitivity to the triazole demethylation inhibitor (DMI) fungicides myclobutanil and difenoconazole. Relative expression (RE) of the CYP51A1 gene was significantly greater (P < 0.0001) for isolates with resistance to both fungicides (MRDR phenotype) or with resistance to difenoconazole only (MSDR phenotype) compared with isolates that were resistant only to myclobutanil (MRDS phenotype) or sensitive to both fungicides (MSDS phenotype). An average of 9- and 13-fold increases in CYP51A1 RE were observed in isolates resistant to difenoconazole compared with isolates with MRDS and MSDS phenotypes, respectively. Linear regression analysis between isolate relative growth on myclobutanil-amended medium and log10 RE revealed that little to no variability in sensitivity to myclobutanil could be explained by CYP51A1 overexpression (R2 = 0.078). To investigate CYP51A1 upstream anomalies associated with CYP51A1 overexpression or resistance to difenoconazole, Illumina sequencing was conducted for three isolates with resistance to difenoconazole and one baseline isolate. A repeated element, “EL 3,1,2”, with the properties of a transcriptional enhancer was identified two to four times upstream of CYP51A1 in difenoconazole-resistant isolates but was not found in isolates with the MRDS phenotype. These results suggest that different mechanisms may govern resistance to different DMI fungicides in the triazole group.

scholarly journals Disease Incidence–Severity Relationships on Leaflets, Leaves, and Fruit in the Pecan–Venturia effusa Pathosystem

Plant Disease ◽  
2019 ◽  
Vol 103 (11) ◽  
pp. 2865-2876 ◽  
Author(s):  
Clive H. Bock ◽  
Kuo-Szu Chiang
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Disease Incidence ◽  
Linear Regression Analysis ◽  
Southeastern United States ◽  
Accurate Data ◽  
Incidence Data ◽  
High Incidence ◽  
Labor Requirements ◽  
The Relationship

The most destructive disease of pecan in the southeastern United States is scab, caused by Venturia effusa. Incidence (I)-severity (S) relationships have not previously been characterized in this pathosystem, but incidence measures can save time and should have higher accuracy compared with estimates of severity. Ten scab-susceptible cultivars and seedling trees were assessed for I and S of scab on fruit (1,972 trees) and foliage (compound leaves and leaflets, 1,129 trees) between 2010 and 2014. Samples were assessed on a tree basis, and sample size ranged from 10 to 100 specimens per tree. The range in mean I and S was different depending on the organ (fruit I = 0 to 100%, S = 0 to 100%; compound leaves and leaflets, I = 0 to 100%, S = 0–10.1%, respectively). However, mean I could be 100% at a mean S < 2.0% for fruit, compound leaves, and leaflets. Both I and S data were transformed by complementary log-log prior to linear regression analysis. A linear regression model described the relationship between transformed I and S per tree for fruit (P ≤ 0.0001, R2 = 0.61), compound leaves (P ≤ 0.0001, R2 = 0.82), and leaflets (P ≤ 0.0001, R2 = 0.91) for all cultivars. The regression analysis showed significant effects of cultivar and year on the relationship between I and S; therefore, separate analyses were performed for each cultivar and year. Back-transformed predicted severity values showed that the differences among cultivars and years were negligible at severity <80%, and were generally numerically small at severity >80%. The observation that low severity persists until a high incidence of scab is achieved may limit the ability of incidence data to clearly differentiate treatment effects, even when based on the CLL transformation. But if found to be effective, and if used, it would reduce the labor requirements and result in more accurate data being obtained, as incidence estimates do not tend to suffer from the same subjective biases as do visual estimates of severity.

ANALISIS PENGARUH INFLASI, KURS DAN IHSG TERHADAP RETURN REKSA DANA SAHAM PT NIKKO SECURITIES INDONESIA PERIODE 2014-2017

2019 ◽  
Vol 2 (2) ◽  
pp. 103
Author(s):  
Muhammad Rois Rois ◽  
Manarotul Fatati Fatati ◽  
Winda Ihda Magfiroh
Keyword(s):  
Regression Analysis ◽  
Exchange Rate ◽  
Linear Regression ◽  
Multiple Linear Regression ◽  
Stock Price ◽  
Price Index ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Equity Fund ◽  
Stock Price Index

This study aims to determine the effect of Inflation, Exchange Rate and Composite Stock Price Index (IHSG) to Return of PT Nikko Securities Indonesia Stock Fund period 2014-2017. The study used secondary data obtained through documentation in the form of PT Nikko Securities Indonesia Monthly Net Asset (NAB) report. Data analysis is used with quantitative analysis, multiple linear regression analysis using eviews 9. Population and sample in this research are PT Nikko Securities Indonesia. The result of multiple linear regression analysis was the coefficient of determination (R2) showed the result of 0.123819 or 12%. This means that the Inflation, Exchange Rate and Composite Stock Price Index (IHSG) variables can influence the return of PT Nikko Securities Indonesia's equity fund of 12% and 88% is influenced by other variables. Based on the result of the research, the variables of inflation and exchange rate have a negative and significant effect toward the return of PT Nikko Securities Indonesia's equity fund. While the variable of Composite Stock Price Index (IHSG) has a negative but not significant effect toward Return of Equity Fund of PT Nikko Securities Indonesia

Struktur Organisasi, Desain Kerja, Budaya Organisasi Dan Pengaruhnya Terhadap Produktivitas Karyawan Studi Kasus Pada PT. XX Di Jakarta

Liquidity ◽  
2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Yanti Budiasih
Keyword(s):  
Organizational Culture ◽  
Regression Analysis ◽  
Linear Regression ◽  
Organizational Structure ◽  
Research Method ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Job Design ◽  
Employee Productivity ◽  
Dominant Influence

The objectives of this study are to analyze changes in organizational structure, job design, organizational culture and its influence on employee productivity at PT. XX in Jakarta and to identify variables that have a dominant influence on the productivity of employees. The research method used is using multiple linear regression analysis. The results show that the all variables simultaneously and partially change the organizational structure, job design, and organizational culture has a significant impact on employee productivity at PT. XXin Jakarta.

The Contribution of Sexual Identity Towards the Students’ Perception of Lesbian, Gay, Bisexual, and Transgender

10.32698/0642 ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 120
Author(s):  
Wiwi Delfita ◽  
Neviyarni S. ◽  
Riska Ahmad
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Sexual Identity ◽  
Student Perceptions ◽  
Undergraduate Students ◽  
Linear Regression Analysis ◽  
Sampling Technique ◽  
Simple Linear Regression ◽  
Simple Linear Regression Analysis ◽  
Bisexual And Transgender

Some students perceive lesbian, gay, bisexual, and transgender (LGBT) positively, even though LGBT is a sexual deviation that is not appropriate with values and norms. There are several factors that influence an individual's perception of LGBT, including sexual identity. This study aims at looking at the contribution of sexual identity to student perceptions about LGBT. This research used a quantitative approach with a descriptive method and a simple linear regression analysis. The sample of this research was 385 taken from 15.752 undergraduate students of Universitas Negeri Padang which the sample was drawn by using the Slovin formula and continued with a Proportional Random Sampling technique. The instrument used was the Guttman model's sexual identity scale and the scale of students' perceptions of the LGBT Likert model. After analyzing the data with the descriptive technique and the simple linear regression analysis, the results showed that sexual identity significantly contributed to the students' perceptions of LGBT. This research has implications as a basis for counselors to help students avoid sexual identity mismatches and prevent the emergence of positive perceptions of LGBT.

Pengaruh Kepemimpinan dan Disiplin Kerja Terhadap Kinerja Karyawan: Studi Kasus PT Sucofindo Palembang Indonesia

MBIA ◽  
2019 ◽  
Vol 18 (1) ◽  
pp. 76-84
Author(s):  
Muhammad Idris ◽  
Dian Novita Sari
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Random Sampling ◽  
Linear Regression Analysis ◽  
Secondary Data ◽  
Multiple Linear Regression Analysis ◽  
Primary Data ◽  
Collection Method ◽  
Analysis Techniques ◽  
Analysis Technique

The problem in this study is whether there is an influence of leadership and work discipline on the employees’ performance of PT.Sucofindo Palembang City. This research includes associative research. The sample in this study were 88 respondents, with propotionate random sampling analysis technique. The data used were primary data and secondary data. Data collection method through questionnare. Analysis techniques using multiple linear regression analysis, F test (Simultaneoys) and t test (partial) and determination coeffiecient. The results show that there is influence of leadership and work discipline on the performance of PT.Sucofindo Palembang City.

PENGARUH KUALITAS PELAYANAN DAN WORD OF MOUTH TERHADAP KEPUTUSAN PEMBELIAN DI KAFE POTRET MEDAN

2019 ◽  
Vol 13 (2) ◽  
pp. 199
Author(s):  
Asrye Tutur Sinaga ◽  
Nurul Wardani
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Service Quality ◽  
Word Of Mouth ◽  
Hypothesis Test ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Quality Data ◽  
Purchasing Decisions ◽  
Study Hypothesis

AbstrakPenelitian ini bertujuan untuk mengetahui dan dapat menjelaskan pengaruh Kualitas Pelayanan dan Word Of Mouth terhadap Keputusan pembelian di Kafe Potret Medan. Populasi dalam penelitian ini adalah 700 orang ditentukan dari jumlah pengunjung Kafe Potret Medan dalam kurun waktu satu minggu, dan sampel yang digunakan berjumlah 88 pengunjung. Sedangkan tehnik pengumpulan data menggunakan angket (kuesioner) dan pengujiannya yaitu uji kualitas data dan uji asumsi klasik.Pengujian hipotesis menggunakan analisis regresi linier berganda, uji F, uji t, dan uji R2. Hipotesis penelitian dimensi Kualitas Pelayanan dan Word Of Mouth secara parsial terhadap Keputusan Pembelian diterima jika t hitung > t tabel dengan tingkat signifikan 0.05.Nilai t tabel dalam penelitian ini 1,662. Nilai t hitung variabel X1 sebesar 1,990 t hitung  > t tabel maka hipotesis diterima, nilai t hitung variabel X2 sebesar 2,628 t hitung > t tabel maka hipotesis diterima. Dari 2 variabel, variabel Word Of Mouth yang paling dominan mempengaruhi Keputusan Pembelian  sebesar 2,628. Kata Kunci : Kualitas Pelayanan, Word Of Mouth, Keputusan Pembelian AbstractThe purpose of this study is to identify and able to explain the influence of Service Quality and Word Of Mouth to Purchasing Decisions of Kafe Potret Medan. The population in this study were 700 people from visitors Kafe Potret Medan in one week, and the samples used were 88 visitors. While the techniques of data collection using the questionnaire and use the test of quality data and classical assumption. The hypothesis test uses multiple linear regression analysis, F test, R square and t test. The study hypothesis was partially of Service Quality and Word Of Mouth dimension to  Purchasing Decisions is acceptable if t hitung > t tabel with a significant level 0.05. The t tabel value in this study 1.662. The t hitung X1 is 1.990 that mean t hitung > t tabel then the hypothesis is accepted, t hitung X2 is 2.628 that mean t hitung > t tabel then the hypothesis is accepted. From 2 variables fascination that the most dominant variable for Purchasing Decisions is Word Of Mouth of 2.628. Keywords : Service Quality, Word Of Mouth, Purchasing Decisions

PENGARUH INTELLECTUAL CAPITAL TERHADAP KINERJA KEUANGAN PADA PERUSAHAAN BARANG KONSUMSI YANG TERDAFTAR DI BEI TAHUN 2015-2017

2019 ◽  
Vol 3 (2) ◽  
pp. 26
Author(s):  
Niken Ayu Wulandari ◽  
Tegoeh Hari Abrianto ◽  
Edi Santoso
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Financial Performance ◽  
Intellectual Capital ◽  
Stock Exchange ◽  
Linear Regression Analysis ◽  
Sampling Technique ◽  
Simple Linear Regression ◽  
Return On Equity ◽  
Asset Turnover

This research to analyze and evaluate intellectual capital on financial performance obtained by return on equity, asset turnover and growth in revenue. The population in this study are consumer goods companies listed on the Stock Exchange in 2015-2017. The research sample was received by 21 companies obtained by using purposive sampling technique. The analytical method used is simple linear regression analysis with the SPSS version 20 application and uses the VAICTM method to measure intellectual capital. The results of this study indicate that intellectual capital has a significant effect on financial performance generated by return on equity, but intellectual capital does not have a significant effect on financial performance required by asset turnover and growth in revenue.

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