Agricultural aviation research

A compilation of papers, comments, and results is provided during a workshop session. The purpose of the workshop was to review and evaluate the current state of the art of agricultural aviation, to identify and rank potentially productive short and long range research and development areas, and to strengthen communications between research scientists and engineers involved in agricultural research. Approximately 71 individuals actively engaged in agricultural aviation research were invited to participate in the workshop. These were persons familiar with problems related to agricultural aviation and processing expertise which are of value for identifying and proposing beneficial research

Droplet size and spray volume effects on honey mesquite mortality with clopyralid

The effects of droplet size and spray volume (spray-mixture application rate) on honey mesquite (Prosopis glandulosa Torr.) mortality were evaluated using 0.55 to 0.58 kg ae (acid equivalent) ha-1 clopyralid (3,6 dichloro-2-pyridinecarboxylic acid). A factorial combination of 3 spray volumes (19, 37, and 75 liters ha-1) and droplet sizes of 325 +/- 25, 475 +/- 25, and 625 +/- 25 micrometers nominal volume median diameter were replicated 3 times at both Andrews and Big Lake, Tex., during June 1989. The experiment was repeated in 1990 at Big Lake and Campbellton, Tex., without the 75 liters ha-1 spray volume. Honey mesquite mortality and canopy reduction 16 months after application were significantly less on the 625 micrometer droplet treatments in 2 of 4 experiments, when compared to plots treated with smaller droplet sizes. Mortality increased with larger spray volumes, particularly with 625 micrometer droplets. Relative mortality data from the 4 experiments clearly demonstrated that larger droplet sizes require larger spray volumes for greatest efficacy.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Produção e utilização de gotas com diâmetro uniforme The generation and use of uniformly sized droplets

A execução da pesquisa com freqüência requer o desenvolvimento de aparelhagem específica. Para estudo dos parâmetros das populações de gotas produzidas por pulverizadores é necessário conhecer o fator de espalhamento de diversas formulações sobre superfícies de amostragem (papel kromekote, melamina (fórmica), vidro etc.). Essa determinação requer aparelhagem geradora de gotas com diâmetro uniforme. Com este objetivo principal, realizou-se o presente trabalho. Além de sua utilização para investigar o comportamento físico da pulverização, o aparelho poderá ter outras aplicações no campo da biologia, como a distribuição uniforme de esporos em dose determinada sobre superfícies vegetais, permitindo, também, observações sobre o efeito tóxico de determinadas doses de defensivos sobre vegetais e animais. O aparelho produziu gotas com diâmetro que, em média, apresentaram coeficiente de variação de 2,36%. o fator de espalhamento para solução aquosa de rodamina a 0,2% sobre papel kromekote apresentou a variação de 1,32 a 1,71 quando se usaram, respectivamente, gotas entre 98 e 325 micra. Para Malathion a 96% de principio ativo, sobre papel kromekote, as gotículas apresentaram fatores de espalhamento variando de 4,09 a 5,18 quando se utilizaram gotas entre 80 e 217 micra. A melamina branca (fórmica) apresentou menores variações nesse fator quando lhe foi aplicado o Malathion.<br>This paper deals with the construction and use of a spinning disc atomizer that produces uniformly sized droplets. The device has a special use in the determination of the spread factor on several sampling surfaces (Kromekote paper, glass, plastic etc.). Furthermore, it permits the study of spraying performance, the inoculation of known spore doses of fungi and observations about toxical effects of pesticides on vegetables and animals. The apparatus showed a narrow droplet size spectrum, with a coefficient of variation about 2.36%. The spread factor of rodhamine B 0.2% in water solution showed to be of 1.32 and 1.71, respectively, when droplets of 98 and 325 micra were used, on Kromekote paper. With Malathion, 96% of active ingredient, the spread factors on Kromekote paper were 4.09 and 5.18 when droplets of 80 and 217 micra were spread. Melamine (Fórmica) showed a small variation in spread factor when sprayed with Malathion