scholarly journals Evaluation of Experimental Compounds for Leafminer Control on Lettuce, 1996

1998 ◽  
Vol 23 (1) ◽  
pp. 107-108
Author(s):  
J. C. Palumbo ◽  
F. J. Reyes
Keyword(s):  
F Test ◽  
Insecticide Efficacy ◽  
University Of Arizona ◽  
Recorded Data ◽  
Direct Seeded ◽  
Mean Differences ◽  
The University ◽  
One Way Anova

Abstract Lettuce was direct seeded on 13 Sep. at the University of Arizona Yuma Agricultural Center. Each plot consisted of four, 60-ft-long beds spaced 42 inches apart and bordered on each side by 2 untreated beds. Plots were arranged in a CRB design with 4 replicates. Prior to application of treatments, a Lannate (0.75 lb (AI)/acre) and Karate (0.3 lb (AI)/acre) spray was applied to all plots on 27 Sep to control lepidopterous larvae. Foliar treatments were applied on 10 and 17 Oct with a tractor drawn sprayer operated at 150 psi, delivering 45 gpa. No spreader-sticker was added to any of the spray treatments. Insecticide efficacy was determined by randomly selecting 10 lettuce plants in each replicate and placing them in emergence containers for 3-4 weeks to allow for pupation and emergence of liriomyza and parasitoid adults. Adults were counted and their species recorded. Data were analyzed as a one-way ANOVA using a protected LSD F test to distinguish treatment mean differences.

scholarly journals Evaluation of Pyrethroids and Selected Insecticides for Control of Cabbage Looper in Broccoli

1997 ◽  
Vol 22 (1) ◽  
pp. 86-86
Author(s):  
J. C. Palumbo
Keyword(s):  
Cabbage Looper ◽  
F Test ◽  
Double Row ◽  
Insecticide Efficacy ◽  
Direct Seeded ◽  
Pre Treatment ◽  
Mean Differences

Abstract Broccoli was direct seeded into double-row beds on 21 Sep at the Yuma Valley Agricultural Center, Yuma, AZ. Each plot consisted of four, 30 ft long beds spaced 42 inches apart and bordered on each side by an untreated bed. Plots were arranged in a CRB design with 4 replicates. Foliar applications were made on 30 Oct and 4 Nov with a hand-held CO2 sprayer operated at 50 psi, delivering 20 gpa. Spreader-sticker (Kinetic) was included in all spray treatments at a rate of 0.125% of the total volume. Insecticide efficacy was determined by counting the total number of small (1 st and 2nd instars) and large (>2nd instar) CL larvae on 5 randomly selected broccoli plants per replicate. A pre-treatment sample was taken on 29 Oct and evaluations were made 5 DAT on 4 and 9 Nov. Data were analyzed as a 1-way ANOVA using a protected LSD F test to distinguish treatment mean differences.

scholarly journals Efficacy of Pyrethroid & Endosulfan Combinations Against Whitefly Adults on Spring Cantaloupes, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 103-104
Author(s):  
J. C. Palumbo ◽  
C. H. Mullis
Keyword(s):  
Analysis Of Variance ◽  
Furrow Irrigation ◽  
F Test ◽  
Local Practices ◽  
University Of Arizona ◽  
Direct Seeded ◽  
The University

Abstract Cantaloupes were direct seeded on 9 Mar into pre-irrigated beds spaced 80 inches apart at the University of Arizona, Yuma Valley Agricultural Center, Yuma, AZ. Plots consisted of 4 beds, 60 ft long with a 13 ft buffer between plots. Plot preparation and seasonal maintenance followed local practices. Plots were established and insecticide incorporated with furrow irrigation. Plots were arranged in a RCB design with 4 replicates. Foliar applications were made with a tractor drawn sprayer that delivered 48 gpa at 320 psi on 13 Apr, 3, 17 May. Adult efficacy was assessed by counting the number of adults per leaf from each of 10 leaves per plot, 1 day before treatments were applied and 4, and 7 days after treatment. Because of heterogeneity of mean variances, insect data was first transformed (log10 x + 1) before analysis of variance. Treatment differences among means were estimated with the Ryan-Einot-Gabriel-Welsch multiple F test.

scholarly journals Efficacy of Selected Insecticides for Control of Cabbage Looper in Cauliflower

1997 ◽  
Vol 22 (1) ◽  
pp. 116-116
Author(s):  
J. C. Palumbo
Keyword(s):  
Cabbage Looper ◽  
F Test ◽  
Insecticide Efficacy ◽  
Direct Seeded ◽  
Mean Differences

Abstract Cauliflower was direct seeded into on 21 Sep at the Yuma Valley Agricultural Center, Yuma, Az. Each plot consisted of four, 30-ft-long beds spaced 42 inches apart and bordered on each side by two untreated beds. Plots were arranged in a CRB design with 4 replicates. Foliar applications were made on 10 and 14 Oct with a hand-held CO2 sprayer operated at 50 psi, delivering 20 gpa. Spreader-sticker (Kinetic) was included in all spray treatments at a rate of 0.125% of the total volume. Insecticide efficacy was determined by counting the total number of small (1 st and 2nd instars) and large (>2nd instar) CL on 5 randomly selected plants replicate. Data were analyzed as a 1-way ANOVA using a protected LSD F test (P = 0.05) to distinguish treatment mean differences.

scholarly journals Control of Whiteflies with Imidacloprid on Fall Cantaloupes, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 104-104 ◽  
Author(s):  
J. C. Palumbo ◽  
C. H. Mullis ◽  
F. J. Reyes
Keyword(s):  
Seed Treatment ◽  
F Test ◽  
Local Practices ◽  
University Of Arizona ◽  
Direct Seeded ◽  
The University

Abstract Cantaloupes were direct seeded on 23 Aug into beds spaced 80 inches apart at the University of Arizona, Yuma Valley Agricultural Center, Yuma, AZ. Plots consisted of 4 beds, 50 ft long with a 20 ft buffer between plots. Plot preparation and seasonal maintenance followed local practices. Plots were arranged in a RCB design with 4 replicates. Admire 2F treatments were applied 2 in. sub-seed furrow by injecting the material into the beds with long, narrow shanks in 20 GPA total volume of water before seeding. The Gaucho seed treatment was formulated at a rate of 35 g AI of imidacloprid/kg of cantaloupe seed. Foliar applications were made with a tractor drawn sprayer that delivered 48 gpa at 320 psi. The Capture+Thiodan mixture was applied on 8, 12, 20, and 27 Sep. Provado and Pyriproifen were applied on 8, 12, 20, 27 Sep and 7, 16 Oct. SPWF densities were estimated by counting the number of eggs and nymphs on two-cm2 disk sections taken from each of 20 leaves per plot on 7 Sep, 28 Sep and 2 Nov. Because of heterogeneity of mean variances, insect data was transformed (log10 x + 1) prior to analysis. Treatment differences among means were estimated with the Ryan-Einot-Gabriel-Welsch multiple F test.

Approximate Sample Size Formulas for Testing Group Mean Differences When Variances Are Unequal in One-Way ANOVA

2008 ◽  
Vol 68 (6) ◽  
pp. 959-971 ◽  
Author(s):  
Jiin-Huarng Guo ◽  
Wei-Ming Luh
Keyword(s):  
Sample Size ◽  
Power Level ◽  
Maximum Deviation ◽  
F Test ◽  
Unequal Variances ◽  
Population Means ◽  
Mean Differences ◽  
Theoretical Results ◽  
One Way Anova ◽  
Testing Group

This study proposes an approach for determining appropriate sample size for Welch's F test when unequal variances are expected. Given a certain maximum deviation in population means and using the quantile of F and t distributions, there is no need to specify a noncentrality parameter and it is easy to estimate the approximate sample size needed for heterogeneous one-way ANOVA. The theoretical results are validated by a comparison to the results from a Monte Carlo simulation. Simulation results for the empirical power indicate that the sample size needed by the proposed formulas can almost always achieve the desired power level when Welch's F test is applied to data that are conditionally nonnormal and heterogeneous. Two illustrative examples of the use of the proposed procedure are given to calculate balanced and optimal sample sizes, respectively. Moreover, three sample size tables for two-, four-, and six-group problems are provided, respectively, for practitioners.

scholarly journals Control of Sweetpotato Whitefly in Cantaloupe with Various Pesticides, 1992

1994 ◽  
Vol 19 (1) ◽  
pp. 80-80 ◽  
Author(s):  
J. C. Palumbo ◽  
C. H. Mullis ◽  
F. J. Reyes
Keyword(s):  
Cucumis Melo ◽  
Block Design ◽  
Bottom Surface ◽  
Local Practices ◽  
Water Plant ◽  
University Of Arizona ◽  
Randomized Complete Block Design ◽  
Direct Seeded ◽  
The University ◽  
Terminal Area

Abstract Cantaloupes, Cucumis melo, ‘Topmark’ were direct seeded on 3 Mar into single row “yuma beds” on 203 cm centers and thinned to 30 cm intervals at the University of Arizona, Yuma Valley Agricultural Center. Plots consisted of 4 beds, 18 m long with a 3.6 m buffer between plots. Plot preparation and seasonal maintenance followed local practices. Plots were arranged in a randomized complete block design with 4 replicates. Applications were made with a 4-row highpressure, electrostatic boom sprayer equipped with stainless steel, hollow-cone nozzles (TX-18) spaced at 50 cm and delivered 563 liters/ha at 400 psi. Admire was applied as a soil drench in 40 oz of water/plant one week after thinning (5 Apr). Foliar applications were initiated when immature whitefly densities exceeded 3 nymphs/leaf. A total of 3 applications of CGA215944 and Fenoxycarb were made on 29 Apr and 5, 14 May. The remaining foliar treatments were applied 5 times on 29 Apr, 5, 14, 20, and 28 May. The pH of the application water was 7.1. A spreader/sticker was not used. Insect data were collected only from the inner two beds of each plot. Plots were sampled weekly beginning on 14 Apr, and terminating on 9 June. Adult SPWF were assessed by randomly selecting 20 leaves from the terminal area on primary vines (4th fully expanded leaf from the apex of the vine) and counting the number of live adults on the bottom surface. Counts were made at sunrise between 0500-0600 hrs. Immatures were assessed by counting the number of eggs, small nymphs, large and red-eyed nymphs, and eclosed pupal cases on two-cm2 disk sections from each of 10 leaves per plot.

scholarly journals Evaluation of Aphid Control in Lettuce with Admire Applied Through Drip Irrigation

1997 ◽  
Vol 22 (1) ◽  
pp. 137-137 ◽  
Author(s):  
J. C. Palumbo ◽  
C. H. Mullis ◽  
F. J. Reyes
Keyword(s):  
Drip Irrigation ◽  
Sprinkler Irrigation ◽  
F Test ◽  
Double Row ◽  
Stand Establishment ◽  
Aphid Control ◽  
Direct Seeded ◽  
Plant Data ◽  
Mean Differences ◽  
Overhead Sprinkler

Abstract Lettuce was direct seeded on 29 Nov at the Yuma Valley Agricultural Center, Yuma, AZ. into double row beds on 42 inch centers and stand establishment achieved using overhead sprinkler irrigation. Subsequent irrigations and chemigations were made with sub-surface (6-8”) drip irrigation. Plots consisted of 4 beds, 50 feet long with a two bed buffer between the plots. Plots were arranged in a RCB design with four replications. The four Admire 2F chemigation treatments were applied once 54 d after planting (23 Jan) through the drip system during the last hour of the irrigation run. The two Metasystox-R chemigation treatments were applied through the drip three times on 23 Jan, 1 and 8 Feb. The foliar Metasystox-R + Capture treatment was applied at 60 PSI in 20 gpa total volume on 23 Jan, 1 and 8 Feb. Insect data were collected only from the inner two beds of each plot. Aphid densities were estimated bi-weekly by sampling 10 plants per replicate and counting the total number of aphids per plant. Data were analyzed as a 1-way ANOVA using a protected LSD F test to distinguish treatment mean differences.

scholarly journals Efficacy of Pyrethroids and Lannate on Lepidopterous Larvae in Lettuce, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 124-124
Author(s):  
J. C. Palumbo
Keyword(s):  
F Test ◽  
Double Row ◽  
Insecticide Efficacy ◽  
Direct Seeded

Abstract Lettuce was direct seeded into double-row beds on 9 Sep at the Yuma Valley Agricultural Center, Yuma, Az. Each plot consisted of four, 30 ft long beds spaced 42 inches apart and bordered on each side by an untreated bed. Plots were arranged in a RCB design with 4 replicates. Foliar applications were made on 22 and 30 Sep and with a hand-held CO2 sprayer operated at 60 psi, delivering 20 gal/acre. Spreader-sticker (Kinetic) was included in all spray treatments at a rate of 0.25% of the total volume. Insecticide efficacy was determined by counting the total number of small (1st and 2nd instars) and large (>2nd instar) BAW and CL larvae on 20 randomly selected lettuce plants per replicate. Insect counts were conducted the day of application, 22 and 30 Sep, and at 3 days after treatment, 30 Sep and 3 Oct. Treatment differences among means were estimated with the Ryan-Einot-Gabriel-Welsch multiple F test.

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