scholarly journals Efficacy of Experimental Insecticides to Citrus Thrips on Lemons, 1996

1997 ◽  
Vol 22 (1) ◽  
pp. 62-63
Author(s):  
D. L. Kerns ◽  
T. Tellez

Abstract Eight year old lemon trees in Yuma, AZ, were treated with experimental insecticides for control of citrus thrips. The treatments were arranged in a RCB design, consisting of four replicates. Each plot (30 by 90 ft) consisted of three trees, spaced 30 ft apart, in a row. Applications were made using a backpack air-blast sprayer calibrated to deliver 100 gpa. Treatments were applied approximately seven days after petal fall on Apr 2, Apr 23 and May 08. Evaluations were made on 4 Apr, 9 Apr, 15 Apr, 23 Apr, 25 Apr, 29 Apr, 6 May, 10 May, 13 May, 20 May and 29 May. Percent infested fruit were estimated by sampling ten fruit per tree for the presence or absence of immature CT. Fruit damage was assessed on Aug 19 by rating the degree of rind scarring: 1 = no scarring, 2 = slight scarring around the calyx, 3 = significant scarring around the calyx, 4 = slight scarring on the side of the fruit and 5 = major scarring on the side of the fruit. Percentages fruit infested with immature CT were statistically analysed using a square-root transformation, but the data presented in the tables is untransformed. Differences among treatments were separated using ANOVA and an F protected LSD.

1997 ◽  
Vol 22 (1) ◽  
pp. 64-65
Author(s):  
D. L. Kerns ◽  
T. Tellez

Abstract Eight year old lemon trees in Yuma, AZ were treated with insecticides for control of citrus thrips. The treatments were arranged in a RCB design, consisting of four replicates. Each plot (30 by 90 ft) consisted of three trees 30 ft apart in a row. Applications were made using a backpack air-blast sprayer calibrated to deliver 100 gpa. Treatments were initiated approximately 14 days after petal fall and were applied on Apr 3, Apr 30 and May 15. Evaluations were made on 5 Apr, 9 Apr, 15 Apr, 23 Apr, 29 Apr, 2 May, 6 May, 13 May, 17 May, 20 May and 29 May. Percent infested fruit were estimated by sampling by sampling ten fruit per tree for the presence or absence of immature CT. Fruit damage was assessed on Aug 16 by rating the degree of rind scarring: 1 = no scarring, 2 = slight scarring around the calyx, 3 = significant scarring around the calyx, 4 = slight scarring on the side of the fruit and 5 = major scarring on the side of the fruit. Percentage fruit infested with immature CT were transformed using a square-root transformation for analysis, percentage values are presented in the tables. Differences among treatments were separated using ANOVA and an F protected LSD.


1998 ◽  
Vol 87 (03) ◽  
pp. 131-134 ◽  
Author(s):  
CH Sandoval ◽  
LL Morfin ◽  
BB Lopez

AbstractThe aim of this research was to compare the effectiveness of Baptisia tinctoria 30c and Ciprofloxacin against salmonellosis in fowl. Eight hundred (400 first quality and 400 second quality) poultry birds were used. All were the same commercial brand. There were two treatments, both with four repetitions. Treatment began when chickens were eight days old; two drops/kg live weight/d Baptisia tinctoria or 15 mg/kg live weight/d of Ciprofloxacin. Both treatments lasted ten days and were given in the drinking water. Salmonella diagnostic tests were made on day 0, day 8 and day 49 of age and death rate was when treatments had finished. Death rate values were applied a square root transformation and a 2×2 factorial analysis was made.The mortality for first and second quality fowl in the Baptisia tinctoria group were 0.7125 and 2.037, respectively, and in the Ciprofloxacin group, 0.7245 and 2.1848, respectively. No significant statistical difference was observed (P>0.1) regarding treatments, only regarding different quality fowl (P<0.01). After comparing, Baptisia tinctoria 30c and Ciprofloxacin treatments against salmonellosis, it was concluded that there were no meaningful differences between outcomes.


HortScience ◽  
2014 ◽  
Vol 49 (6) ◽  
pp. 696-700 ◽  
Author(s):  
Sogo Nishio ◽  
Masahiko Yamada ◽  
Norio Takada ◽  
Hidenori Kato ◽  
Noriyuki Onoue ◽  
...  

We evaluated the nut harvesting date (NHD), nut weight (NW), pericarp splitting (PS), and infestation by insects (II) in eight cultivars/selections of Japanese chestnut, including a Japanese–Chinese hybrid, over 6 years. Data were analyzed by analysis of variance (without transformation for NHD, after log-transformation for NW and PS, and after square root transformation for II). The among-tree variance accounted for only 1.1% to 8.5% of the total variance. The variance component resulting from residual factors for the tree × year interaction and sampling errors was the largest component for NW, PS, and II, accounting for 46% to 54% of the total environmental variance. Because tree replication is costly and time-consuming in chestnut breeding, increasing the number of yearly repetitions is more efficient than increasing the number of tree replicates. Broad-sense heritability was 0.84 for NHD, 0.27 for NW, 0.48 for PS, and 0.17 for II in evaluations with one tree without yearly repetition. It increased to 0.91 for NHD, 0.40 for NW, 0.62 for PS, and 0.29 for II in evaluations with one tree in 2 years. For NHD, the heritabilities are sufficiently high to distinguish genetic differences among cultivars/selection. In contrast, the low heritability of II suggests that this trait should not be evaluated with an emphasis on the initial selection stage but rather with an emphasis on the secondary selection stage based on testing at several locations with a large number of yearly and tree replications.


2016 ◽  
Author(s):  
Monica Nordberg ◽  
Douglas M. Templeton ◽  
Ole Andersen ◽  
John H. Duffus

2016 ◽  
Vol 35 (8) ◽  
pp. 741-750
Author(s):  
Zheng-Ling Yang ◽  
Ya-Di Liu ◽  
Xin-Shan Zhu ◽  
Xi Chen ◽  
Jun Zhang

Author(s):  
J. K. Kihlberg ◽  
J. H. Herson ◽  
W. E. Schotz

1987 ◽  
Vol 44 (8) ◽  
pp. 1510-1515 ◽  
Author(s):  
R. L. France

Spatial variability in amphipod (Hyalella azteca) density was examined in 17 Canadian Shield Lakes in south-central Ontario. Aggregation was measured by the exponent of the power relationship between density and variance. The average b index was 1.45, although this value varied depending on lake and habitat type. Whereas this should indicate the use of a fourth-root transformation, neither this nor the logarithmic transformation was as effective as the square-root in stabilizing variance. A literature review suggests that if a universal transformation is sought for benthos data, it should not be the commonly used log transformation. The observation that the square-root transformation seemed to work better on average than the fourth-root transformation, even in the region suggested by theory for the latter, suggests that complications may arise in the uncritical use of Taylor's Power Law.


1987 ◽  
Vol 38 (4) ◽  
pp. 757 ◽  
Author(s):  
RW Kelly ◽  
JP Newnham ◽  
T Johnson ◽  
EJ Speijers

Changes in mean diameter of cotyledons were measured from day 45 to 141 of pregnancy using real time ultrasound on 40 3-6-year-old Merino ewes, averaging 46 kg liveweight at day 45, and carrying one foetus. Observations were made at about 2-weekly intervals. Half of the ewes were sacrificed at day 94 and the remainder at day 141 to correlate the observations taken during pregnancy with actual data. There was a significant quadratic relationship (P < 0.001) between mean cotyledon diameter and a square root transformation of day of pregnancy. Maximum diameter of the cotyledons, as estimated by real time ultrasound, occurred at the observation on day 80 of pregnancy. The between-ewe comparison of mean diameter of the cotyledons measured by ultrasound just prior to slaughter with actual mean diameter recorded at slaughter showed a significant correlation (P < 0.001) for both the day 94 (r = 0.69) and day 141 (r = 0.71) results. Within ewes, the correlation between diameter and weight of the cotyledon was high (0.92, 0.86 for days 94 and 141 respectively), and the slope of the linear regression was less (P < 0.001) on day 141 than day 94 (0.45 v 0.32). Eighty-three per cent of the variation between ewes in total weight of cotyledons on day 94 of pregnancy was accounted for by a regression using sex of foetus, number of cotyledons and mean diameter of cotyledons measured by ultrasound on day 80 of pregnancy. In comparison, for day 141 of pregnancy 49% of the variation between ewes in total weight of cotyledons was accounted for by a regression using mean diameter on day 66 of pregnancy and number of cotyledons. The technique has potential value in studying patterns of development of the cotyledons during pregnancy in the ewe, but further validation is necessary.


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