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Full-Text Articles in Plant Sciences
Comparison Of Sampling Methods Used To Estimate Spider (Araneae) Species Abundance And Composition In Grape Vineyards, Michael J. Costello, Kent M. Daane
Comparison Of Sampling Methods Used To Estimate Spider (Araneae) Species Abundance And Composition In Grape Vineyards, Michael J. Costello, Kent M. Daane
Horticulture and Crop Science
The effectiveness of 3 methods for sampling spiders in grape vineyards was tested. The sampling methods were as follows: (1) a drop-cloth method in which spiders were dislodged from a 5.1-m2 area of grapevine onto a drop cloth, (2) a funnel method in which spiders were dislodged into a 0.74-m2 funnel, and (3) a D-vac method in which 50 sections of grapevine (30-cm sections, total area of 5.4 m2) were suctioned with a gasoline-powered vacuum. Data from all sampling methods were adjusted for area sampled and compared with an absolute control, in which foliage from an entire vine was removed …
Using Impedance For Mechanical Conditioning Of Tomato Transplants To Control Excessive Stem Elongation, Lauren C. Garner, Thomas Björkman
Using Impedance For Mechanical Conditioning Of Tomato Transplants To Control Excessive Stem Elongation, Lauren C. Garner, Thomas Björkman
Horticulture and Crop Science
Mechanical stimulation is known to control excessive stem elongation in highdensity tomato (Lycopersicon esculentum Mill.) transplants. Mechanical stimulation using physical impedance provided height control equivalent to that obtained using brushing. Low-cost materials can be used to apply the impedance. Mylar film in a plastic frame was equivalent to expensive acrylic sheets in its effect on plant height (40 mm shorter than nontreated, a 40% reduction in the elongation rate during the treatment period), stem diameter (18% thicker), and biomass (14% lighter) when they applied a pressure of 66 N·m-2• Stem elongation was not reduced ifless pressure was applied (25 or50 …
Brushing Pansy (Viola Tricolor L.) Transplants: A Flexible, Effective Method For Controlling Plant Size, Lauren C. Garner, F. A. Langton
Brushing Pansy (Viola Tricolor L.) Transplants: A Flexible, Effective Method For Controlling Plant Size, Lauren C. Garner, F. A. Langton
Horticulture and Crop Science
Though brushing is an effective method for controlling excessive elongation in many species, its adoption by the commercial plug transplant industry will depend on the ease and flexibility of its application. Brushing was applied to pansy (Viola tricolor L.) seedlings growing at a density of 1500 plants m-2 by daily stroking with 20/20 gauge netting. In dose response experiments, final petiole length appeared to approach a lower asymptote as number of brush strokes increased, and the number of strokes required to give near full reduction in length increased under environmental conditions favouring extension growth. Ten or 20 daily …
Behavior Of Female Eretmocerus Sp. Nr. Californicus Howard (Aphelinidae: Hymenoptera) Attacking Bemisa Argentifolii Bellows And Perring (Aleyrodidae: Homoptera) On Two Native Californian Weeds, David H. Headrick, Thomas S. Bellows, Jr., Thomas M. Perring
Behavior Of Female Eretmocerus Sp. Nr. Californicus Howard (Aphelinidae: Hymenoptera) Attacking Bemisa Argentifolii Bellows And Perring (Aleyrodidae: Homoptera) On Two Native Californian Weeds, David H. Headrick, Thomas S. Bellows, Jr., Thomas M. Perring
Horticulture and Crop Science
Searching and ovipositional behaviors by female Eretmocems sp. nr. californicus Howard on Bemisia argentifolii Bellows and Perring infesting velvetleaf, Abutilon theophrasti Medic. (Malavaceae), and telegraph weed, Heterotheca grandiflora Nutt. (Asteraceae), were quantified. Adult female behaviors were described and quantified for E. sp. nr. californicus to establish a behavioral time budget analysis. Females departed from leaves of A. theophrasti in 83.3% of the trials, and of those that remained and searched for hosts, walking speeds averaged 0.29 mm/s. Females departed from the leaves of H. grandiflora in 44.4% of the trials, and those remaining readily searched for whitefly hosts with walking …