scholarly journals Control of Aphids on Mustard in a Commercial Field, 1996

1997 ◽  
Vol 22 (1) ◽  
pp. 137-137
Author(s):  
J. V. Edelson ◽  
M. Peters

Abstract A commercial production field of mustard was used for this trial. Plants were grown in 6 row beds on 6 ft centers. The field was direct seeded in Apr approximately 1 mile west of Webbers Falls, OK. Small plots were delimited on one edge of the field. The experimental design was a RCB with 4 replicates and 7 treatments. Insecticide applications were made on 23 and 29 May using a bicycle tire mounted sprayer with 4 hollow cone nozzles (TXVS26) per bed applying 40 gpa solution at 42 psi. Plots were 1 bed wide and 20 ft long with 5 ft alleys between plots. Insect populations were surveyed by examining 5 plants per plot on 29 May (prior to the second application of insecticides) and 3 Jun to determine treatment effects.

1998 ◽  
Vol 23 (1) ◽  
pp. 105-106
Author(s):  
Philip A. Stansly ◽  
C. Mayra ◽  
G Avilez

Abstract A commercial field of staked eggplant was used ap-proximately 45 days after transplanting for this trial in the Culican Valley of Sinaloa, Mexico. The field was 100 m wide and approximately 2 km in length, located between 2 fields of corn. The crop had recently been sprayed with endosulfan (Thiodan®). Consequently, relatively few adult whiteflies could be observed although the presence of eggs and young nymphs indicated the likelihood of increasing infestation, and no further applications were made by the grower for the duration of the trial. Experimental design was completely randomized block with 5 treatments and 4 replicates. Beds were 100 m in length running north and south with 1.5 m between centers and 2 rows per bed. Plots were 4 beds wide and 15 m long with 1.5 m between plots (90m2). Three weekly applications were made beginning on 12 Feb with 2 Maruyama™ motorized backpack sprayers equipped with a hand-held boom carrying 2 bronze T-Jet™ D2 hollow cone nozzles containing #45 spinner plates. Each bed was sprayed from both sides with 5 liters per replicate of each treatment, delivering a volume of 60.5 gpa. Each plot was sampled for whitefly adults and immature stages prior to application. A beat pan made of an aluminum cake pan 22.5cm X 32.5 cm painted black and covered with a film of vegetable oil and liquid detergent (9:1) was used to sample adults. Three samples were taken in each plot by beating the pan 10 times against the foliage in the middle 2 rows and counting the whiteflies trapped in the oil mixture. Immatures were sampled by counting all whitefly eggs, small nymphs, large nymphs, and pupae in 4 lensfields of 1.77 cm2 per leaf (3 leaves per plot). Additional samples were taken 3 days after each successive treatment. Small nymphs, large nymphs, and pupae were combined as “immatures” for analysis.


1998 ◽  
Vol 23 (1) ◽  
pp. 91-91
Author(s):  
J. V. Edelson ◽  
M. Peters ◽  
J. Duthie ◽  
W. Roberts

Abstract Collard seed was planted in Mar at the AREC, Lane, OK. The experimental design was a RCB with 4 replicates and 9 treatments. Plots were 2 rows wide (72 inches) and 20 ft long with 20 ft alleys cut between plots. Plots were treated with insecticides using a CO2-powered backpack sprayer with a broadcast application of 72 inches from 4 hollow-cone nozzles applying 33 gal/A at 40 psi. Plots were treated on 4, 8, and 14 Jul. Plots were surveyed to determine larval abundance on 7, 11, and 17 Jul by examining 3 plants per plot and recording all larvae present.


2019 ◽  
Vol 9 (4) ◽  
pp. 596-602
Author(s):  
Francisca Sonally Oliveira ◽  
Lindomar Maria da Silveira ◽  
Salvador Barros Torres ◽  
Ferdinando Monteiro Carvalho Dias da Costa ◽  
Maclayver Christiano Caetano Nunes ◽  
...  

Luffa cylindrica Roemer is abundant in countries of Asia, Central America and South America. Dormancy in luffa seeds is caused by the impermeability of the coat, which may be a major obstacle in the commercial production of seedlings for the cultivation of this species. Thus, this study aimed to evaluate different methods to break dormancy in different accessions of luffa. The experimental design was completely randomized, in a 6 (accessions) x 5 (dormancy breaking treatments) factorial arrangement, with four replicates. Seeds were planted on expanded polystyrene trays, containing commercial substrate Plantmax®. The analyzed variables were: emergence percentage; emergence speed index; number of true leaves; plant height; stem diameter; root length; shoot fresh and dry matter, and root dry matter. The first two variables were analyzed in the entire experimental plot and the others only in the evaluated area of the plot. Scarification with sandpaper nº 80 and cut with pruning pliers on the opposite end to the hilum were the methods of dormancy breaking which led to the best results. Due to the variability of the results among the accessions, it was not possible to recommend one method of dormancy breaking for luffa seeds that is generalized for all of them.


1996 ◽  
Vol 21 (1) ◽  
pp. 99-99
Author(s):  
K. A. Sorensen ◽  
C. Wade Holloway

Abstract ‘Gourmet’ cabbage was direct seeded in early Mar near Weeksville, NC. Single row plots 10 ft. long on 42 inch centers were replicated 4 times in a RCB design. Alleys of 5 ft. were used between replicates. Treatments were applied with a CO2 pressurized backpack sprayer using a single hollow cone nozzle (18X) operating at 60 psi to deliver 54.5 gal/acre. Applications with Triton AG-98 (spreader) were made with all treatments 2, 9, 16 and 23 May. Visual estimates of foliar damage and insect counts were made 9, 16, 23 and 30 May. No CL were present on 9 and 16 May.


2017 ◽  
Vol 38 (3) ◽  
pp. 1201
Author(s):  
Núbia Maria Correia ◽  
Agnaldo Donizete Ferreira de Carvalho

Herbicide application is a method for weed control in carrot crops. However, the choice of the chemical treatment (herbicide, association of products, dose, and time of application) should consider its selectivity to the crop. It is desired to analyze the selectivity of linuron for carrot plants, when sprayed on pre-emergence and post-early cultivated plants. Two experiments were carried out in the field in an area of the commercial production of carrots, one with the Verano cultivar and the other with BRS Planalto. Both experiments included an experimental design with randomized blocks in a factorial 2 x 4 + 1 with six and four replications for the experiments with Verano and BRS Planalto, respectively. The herbicide linuron (675 and 990 g a.i. ha-1) was sprayed at four times, counting from the carrot sowing day: in the pre-emergence of the crop at 0, 3, and 6 days after sowing (DAS) and in the post-early emergence at 9 DAS, when the plants had 1 or 2 cotyledons. An untreated control was maintained as an additional treatment. Linuron was selective for the carrot plant cultivars Verano and BRS Planalto, in both doses tested, when sprayed in the pre-emergence, up to six days after sowing, and in the post-early (plants with 1 or 2 cotyledon leaves) at nine days after sowing.


1998 ◽  
Vol 23 (1) ◽  
pp. 142-143
Author(s):  
Susan E. Webb

Abstract Insecticides specific for lepidopterous pest-were compared with a standard, Thiodan, and an untreated check for control of pickleworm. Squash was direct seeded on 1 Apr at the Central Florida Research and Education Center, Leesburg, FL. Each plot consisted of four 25-ft rows, 6 ft apart with plants spaced 2.5 ft apart. Treatments were replicated four times in an RCB design. All chemicals were applied with a 2-row tractor-mounted boom sprayer with 18 Albuz (lilac) ceramic hollow-cone nozzles spaced 8 inches apart, delivering 133 gpa at 200 psi. Latron CS-7, a surfactant, was tank-mixed with Confirm and RH-2485 at a concentration of 0.12% vol:vol. Treatments were applied weekly from 14 May to 11 Jun. Fruits were harvested, separated into marketable and damaged, counted, and weighed three times per week from 12 May to 16 Jun. An analysis of variance and a mean separation test (WD) were used to determine significant differences among treatments.


Author(s):  
Jussara Cristina Firmino Da Costa ◽  
Rejane Maria Nunes Mendonça ◽  
Gerciane Cabral Da Silva ◽  
Silvanda de Melo Silva ◽  
Walter Esfrain Pereira ◽  
...  

In the commercial production of guava seedlings (Psidium guajava L.) the quality of the cuttings, homogeneity, high percentage of rooting are the factors important to be analyzed. Therefore, as the Século XXI cultivar is recent, it is necessary to do more studies regarding the behavior of this guava to the factors that aid in the rhizogenic process. The objective of this work was to verify the concentrations of indolebutyric acid (IBA) that provide the best rooting of cuttings herbaceous and semihardwood, as well as to verify the best kind of cuttings used for vegetative propagation the guava cuttings cultivar ‘Século XXI’. The experimental design was completely randomized in a 5 x 2 + 1 factorial design, beginning with five concentrations of IBA (0, 1000, 1500, 2000 and 2500 mg L-1), two kinds of cuttings (herbaceous and semihardwood) and one control treatment (immersed in distilled water for 12 hours), with four replications and 10 cuttings per plot. In relation of the variables: the percentage of cuttings live without roots, callus, number of roots and dry weight of shoots did not present significant interaction among treatments, not adjusting to any regression model. Therefore, concluding that the herbaceous cutting is the most indicated for the propagation of guava seedlings of ‘Século XXI’; The concentration of 2500 mg L-1 of IBA promotes a higher percentage of rooted semihardwood cuttings without leaf; The hormone solution diluted with alcohol 50% (v/v) resulted in toxicity for herbaceous and semihardwood cuttings cv. Século XXI.


1998 ◽  
Vol 23 (1) ◽  
pp. 138-139 ◽  
Author(s):  
David Riley

Abstract Fresh-market type ‘Fall Green’ spinach, was direct seeded on 11 Oct 1995 in 100-cm-width beds and maintained with standard cultural practices at Weslaco, TX. Plots consisted of two rows by 10 m and were arranged in a RCB design with six treatments and four replicates. Admire (imidacloprid) was applied at planting as an 8-cm banded spray in the seed furrow. All other insecticide treatments were foliar sprays which were initiated when aphid numbers exceeded 1 per leaf. Spray applications were made on January 16, 23 and February 14 with three TX6 hollow-cone tips (Spraying Systems Company) per row. The spray volume was 284 ]/ha. Aphids were counted on one expanded leaf per plant on 5 plants per plot. An additional destructive sample was taken at harvest on 8 and 16 Feb to determine the number of gpa per 10 leaves per plot and number of root aphids per 5 mechanically extracted tap roots. Data were subjected to analysis of variance and LSD tests for separation of treatment means.


HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 584a-584
Author(s):  
Ellen T. Paparozzi ◽  
M. Elizabeth Conley ◽  
Walter W. Stroup

Three cultivars of poinsettia, Freedom Red, Lilo and Red Sails, were grown in a peat:perlite:vermiculite mix according to a commercial production schedule. Twelve selected nitrogen–sulfur fertilizer combinations were applied (125, 150, 175 ppm N with either 12.5, 25, or 37.5 ppm S, 225 and 275 ppm N with either 37.5 or 75 ppm S). The experimental design was a split plot with cultivars as the whole plot and fertilizer levels as the split-plot factor. Mix samples were taken initially, at production week 7 and at the end of the experiment. Nitrate-nitrogen, sulfate-sulfur and total nitrogen were determined. Data were analyzed using SAS PROC MIXED. Visually all cultivars responded similarly to all treatments and were salable. Thus, levels of N as low as 125 or 150 with 12.5 ppm S produced quality plants. Sulfate-S tended to accumulate in the mix while nitrate-N and total N did not. Both nitrate-N and sulfate-S concentrations were affected by an interaction between the cultivar and the amount of S applied with `Freedom' better able to utilize available sulfur. `Lilo' removed more nitrate-N and total N from the mix than `Freedom' which removed more than `Red Sails', but only at specific levels of sulfur. There was no cultivar by nitrogen interaction for any variable measured.


1996 ◽  
Vol 21 (1) ◽  
pp. 252-253
Author(s):  
D. A. Herbert

Abstract Different application schedules with insecticides at different rates were evaluated for control of bollworm in VA. ‘Sure-Grow 501’ cotton was planted 1 May at the Virginia Tech Tidewater Agric. Res. & Ext. Ctr., Suffolk, VA, using a 36-inch row spacing. All treatments were applied with a CO2 pressurized backpack sprayer calibrated to deliver 14.5 gpa at 50 psi through three, D2-13 disc-core hollow cone nozzles per row, one over the top of the row and one on each side. Four application schedule/insecticide rate combinations were tested: 1)3 applications at the standard rate, the 1 st at the egg threshold, the 2nd in 5d, and the 3rd in l0d; 2) 2 applications at the standard rate, the 1st at the egg threshold, the 2nd in 5d; 3) 2 applications, the 1st at the egg threshold using 1.6x the standard rate, and the 2nd in 5d using the standard rate; 4) 1 application at the egg threshold using 1.6x the standard rate. Egg threshold application was based on the presence of 10 or more bollworm eggs per 100 plant terminals, or 2 or more per 100 fruil (squares or bolls). A RCB experimental design was used with 4 replicates; plots were 6 rows by 30 ft. Boll damage and bollworm numbers were determined by sampling 25 randomly selected bolls per plot. Samples were taken at roughly weekly intervals after the occurrence of the egg threshold. Yield was determined by harvesting the 2 center rows of each plot (60 row ft per plot) using a commercial 2-row John Deere cotton combine. Lint values were calculated as 37% of total plot weights, assuming 63% was seed and trash. Data were analyzed using ANOVA and LSD statistical procedures.


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