scholarly journals Flea Beetle Control in Canola, 1994B

1995 ◽  
Vol 20 (1) ◽  
pp. 155-155
Author(s):  
D. E. Bragg ◽  
D. Mayer
Keyword(s):  
Flea Beetle ◽  
Leaf Stage ◽  
Plant Damage ◽  
Total Destruction ◽  
Plant Stand

Abstract Plots were planted 6 May near Pomeroy, WA, at a rate of 6 lb/acre in rows 7 inches apart. Plots were 20 × 2 ft, replicated in a RCBD 4 times, and were situated with replicates perpendicular to a grass field. Precounts (PrCt) of plant stand per 6.6 ft row, and damage on 20 randomly selected plants on a scale of 0 to 6, with 0 = no damage and 6 = total destruction, were made 22 May. Five insecticide treatments were applied with a CO2 backpack sprayer at 20 gpa and 20 psi on 23 May. Conditions at treatment were 80 F° with no wind at 4 pm. Plants were in the first leaf stage. Evaluations of stand reduction and plant damage were made on 2, 5, 7 and 10 DAT. All surviving plants were in the 7 to 9 leaf rosette stage on 10-DAT.

scholarly journals Flea Beetle Control in Lower Rainfall Se Washington, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 205-205
Author(s):  
D. E. Bragg ◽  
D. Mayer
Keyword(s):  
Flea Beetle ◽  
Plant Introduction ◽  
Plant Damage ◽  
Total Destruction ◽  
Cotyledon Stage ◽  
Untreated Check ◽  
Plant Stand

Abstract Plots were planted 9 June at the USDA-ARS Western Plant Introduction Center at Central Ferry, WA at a rate of 6 lb/acre in rows 7 inches apart. Plots were 15 x 3 ft replicated in a RCBD 4 times, and were situated with replicates perpendicular to a crested wheat grass field. Precounts (PrCt) of plant stand per 6.6 ft row, and damage on 20 randomly selected plants on a scale of 0 to 6, with 0 = no damage and 6 = total destruction, were made 21 Jun. A treatment consisting of Furadan CR-10 granules at a rate of 2.5 lb product per acre was applied at seeding. Four other insecticide treatments were made with a CO2 backpack sprayer at 20 gpa and 20 psi on 22 Jun. An untreated check was established. Conditions at treatment were 70°F with a 2 mph wind at 11 a.m. All plants were in the cotyledon stage with meristem visible. Evaluations of stand reduction and plant damage were made on 2, 5, 7, and 10 DAT. All surviving plants were in the rosette stage (5 to 7 leaf) at 10 DAT.

EFFECTS OF FLEA BEETLE FEEDING ON TRANSPLANTED AND DIRECT-SEEDED BROCCOLI

1987 ◽  
Vol 67 (2) ◽  
pp. 549-557 ◽  
Author(s):  
J. J. SOROKA ◽  
M. K. PRITCHARD
Keyword(s):  
Brassica Oleracea ◽  
Flea Beetle ◽  
Leaf Stage ◽  
Summer Generation ◽  
Plant Damage ◽  
South Central ◽  
Flea Beetles ◽  
Direct Seeded ◽  
Second Year ◽  
Field Plots

The effects of flea beetle (Coleoptera: Chrysomelidae) feeding on transplanted and direct-seeded broccoli (Brassica oleracea var. italica Pl.) were studied for 2 yr in field plots in south central Manitoba. Flea beetle populations were monitored in biweekly broccoli plantings and the plots were assessed for stand loss, plant damage and yield. Transplants of 4-, 3-, or 2-wk-old seedlings, direct-seeded plants and direct-seeded plants with carbofuran granules in furrow were compared. The earliest plantings had the greatest mortality, delayed harvest and most prolonged harvest period because of high beetle populations early in the season. Small transplants and newly emerged seedlings were the most severely defoliated by the beetles while broccoli plants beyond the 6- to 8-leaf stage suffered negligible damage. Direct-seeded plants without insecticide had the fewest and generally lowest-quality heads. Over both years direct-seeded broccoli yielded only 37% of the marketable harvest of direct-seeded, insecticide-protected broccoli. The old transplants were the most tolerant to flea beetle attack. Feeding on bud florets of the mature heads by the large summer generation of flea beetles in the second year of the study reduced marketable yields of all treatments.Key words: Flea beetle, broccoli, transplant, direct seed, carbofuran, Brassica oleracea var. italica Pl.

Herbicides compromise biological control of ragwort

2002 ◽  
pp. 147-152
Author(s):  
K. Betteridge ◽  
D. Costall
Keyword(s):  
Biological Control ◽  
Pyrrolizidine Alkaloids ◽  
Animal Health ◽  
Flea Beetle ◽  
Dairy Farm ◽  
Senecio Jacobaea ◽  
Longitarsus Jacobaeae ◽  
High Ester ◽  
Low Levels

In spite of ragwort flea beetle (RFB) being present on a Dannevirke dairy farm, pastures were sprayed each winter to reduce ragwort density and limit the risk of ragwort poisoning of stock. The trial on this farm from June 1999 - October 2001, aimed to determine whether herbicide (H) impacted on RFB and how H and RFB each impacted on ragwort growth and persistence. RFBfree areas were created by spraying with insecticide (I). Effects of ragwort on animal health are also reported. High ester 2,4-D (H) boom-sprayed once only, in June 1999, killed most ragwort plants and reduced RFB larvae densities to low levels before the plants died. Once new ragwort established in treatment H, the plants became infested with RFB larvae. RFB larvae were suppressed by I resulting in ragwort density declining more slowly than in treatments where RFB were not suppressed. Insecticide treatments were stopped after 15 months and, at 24 months, ragwort could not be found within the trial area. Ragwort control was attributed to the cessation of herbicide spraying allowing the RFB population to reach a sufficient density to kill both small and large ragwort plants. Sub-clinical ragwort poisoning was found in livers of culled cows that had grazed on ragwort-dense pastures. Keywords: animal health, biological control, Longitarsus jacobaeae, pyrrolizidine alkaloids, ragwort, ragwort flea beetle, Senecio jacobaea

Ethephon for American Ginseng (Panax quiquefolium L.) Inflorescence Removal

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 481b-481
Author(s):  
A.E. Fiebig ◽  
J.T.A. Proctor ◽  
D. Murr ◽  
R. Releeder
Keyword(s):  
Additive Concentration ◽  
Root Mass ◽  
Panax Quinquefolium ◽  
Fruit Removal ◽  
Plant Damage ◽  
Low Concentrations ◽  
Production Practice ◽  
Whole Plants ◽  
Mass Increase ◽  
Standard Production

Varying concentrations (500-4000 mg·L–1) of ethephon, an ethylene-releasing compound, were applied to 3-year-old ginseng (Panax quinquefolium L.) plants in fields of southern Ontario. The effects of this chemical on fruit removal, plant damage, infructescence morphology, and root mass were studied and compared to the normal practice of manual inflorescence removal. The highest concentrations had the highest rates of removal but also caused the greatest amount of damage to the whole plants when compared to the mid-range concentrations. The lowest concentrations showed less foliar damage but did not provide sufficient fruit removal to mimic hand removal. When individual inflorescences of the ethephon treatments were studied, the seed heads had fewer ripe berries and more unpollinated florets than the untreated controls. When root masses were compared, high and low concentrations showed lower masses than those of the standard production practice of hand removal. However, mid range concentrations showed similar root mass increase to manual removal. When all parameters were considered, the concentration range giving the best results was 1000-1500 mg·L–1. Multiple applications of ethephon, at weekly intervals, had an additive effect on flower removal and plant damage. Treatments having an additive concentration of over 2000 mg·L–1 had detrimental effects on all parameters. Those within the 1000–1500 mg·L–1 range showed the highest similarity to the hand removal benefits.

Indices of Plant Damage and Heritability of Tolerance to the Spotted Alfalfa Aphid in Alfalfa

Crop Science ◽  
1989 ◽  
Vol 29 (6) ◽  
pp. 1337-1340 ◽  
Author(s):  
H. O. Jimenez ◽  
J. L. Caddel ◽  
R. C. Berberet ◽  
R. W. McNew
Keyword(s):  
Plant Damage

Effect of tillage and crop establishment methods on yield and economics of cotton

2018 ◽  
Vol 5 (01) ◽  
Author(s):  
ANIL KHIPPAL ◽  
KAMINI KUMARI S. Bhadauria ◽  
JASBIR SINGH
Keyword(s):  
Conventional Tillage ◽  
Variable Cost ◽  
Cost Ratio ◽  
Zero Tillage ◽  
Benefit Cost Ratio ◽  
Tillage Practices ◽  
Plant Stand ◽  
Method Of Planting ◽  
Benefit Cost ◽  
Very High

In Haryana (India) cotton is generally sown with conventional tillage practices witnesses poor germination and plant establishment. Poor plant stand is attributed by burning of emerging plants due to very high temperature at the time of planting, which is further worsen by crust formation due to pre-monsoon showers. Keeping these points in view, an experiment was conducted with farmers' participatory research mode in village Hajwana of Kaithal district. Cotton sown with zero tillage technique resulted in approximately five percent higher yield i.e. 136.3 kg ha-1 over conventional tillage. Mean returns over variable cost of all the three years were 10.8 percent i.e. Rs. 11794 ha-1 more in zero tillage over conventional tillage. Benefit: cost ratio were 3.86, 3.86 and 4.61 in conventional method of planting, bed planting and zero tillage technique, respectively. Zero tillage planting of cotton reduced fuel consumption by 93.4 % and 91.7 % compared to bed planting and conventional planting respectively.

Sign in / Sign up

Export Citation Format

Share Document