Experiments on the control of the Lucerne flea (Sminthurus viridis (L) and the Red-Legged earth mite (Halotydeus destructor (Tuck.)) in pastures in Western Australia.

1954 ◽  
Vol 5 (2) ◽  
pp. 317 ◽  
Author(s):  
MMH Wallace
Keyword(s):  
Western Australia ◽  
Residual Effects ◽  
Maximum Efficiency ◽  
Halotydeus Destructor ◽  
The Earth ◽  
Highly Effective ◽  
Low Volume

Experiments with BHC, chlordane, and parathion against the lucerne flea (Sminhurus viridis (L.)) and the red-legged earth mite (Halotydeus destructor (Tuck.)) in pastures are described. All insecticides were applied by means of a low-volume boom spray delivering 5 gal per acre. BHC applied at the rate of 2 lb 50 per cent. dispersible powder per acre had no effect on the lucerne flea population but killed approximately 90 per cent. of the earth mites present. Chlordane applied a t the rate of ½ lb per acre achieved no control of either pest. Parathion applied at the rate of ¼ pt of 20 per cent. emulsion per acre gave practically 100 per cent. control of lucerne fleas. Its residual effects were negligible and fleas hatching from eggs laid prior to spraying were not harmed. Equally good immediate control was achieved by applications of parathion at one-half the above concentration. The addition of DDT to the spray ensured the destruction of all earth mites as well as the lucerne flea. DDT gave no evidence of control of the lucerne flea in previous experiments. The experiments show that parathion is a highly effective insecticide against the lucerne flea but for maximum efficiency it should be applied early in the season before any eggs have been laid. The toxicity of the parathion sprays to grazing stock is discussed.

I.—The Physiographic Significance of Laterite in Western Australia

1918 ◽  
Vol 5 (9) ◽  
pp. 385-393 ◽  
Author(s):  
W. G. Woolnough
Keyword(s):  
Western Australia ◽  
The Other ◽  
Rock Weathering ◽  
The Earth ◽  
The One ◽  
Soluble Material

During the last six or seven years a series of valuable papers bearing on the origin of laterite has appeared in the Geological Magazine. The conclusions arrived at have been somewhat diverse and contradictory. Dr. Fermor, on the one hand, regarded the laterites of India as residual in character, and believed that they represented the insoluble residues left in the process of rock weathering after the soluble constituents had been removed in solution. Mr. Simpson, at the other extreme, suggested that they represented the soluble material, leached out of the subjacent rocks during weathering under peculiar conditions, and deposited as a chemically-formed rock by precipitation at the surface of the earth.

scholarly journals Note on horizontal receivers and transmitters in wireless telegraphy

1908 ◽  
Vol 81 (549) ◽  
pp. 394-397
Keyword(s):  
Wave Length ◽  
Current Strength ◽  
Transmitted Wave ◽  
Maximum Efficiency ◽  
Electric Force ◽  
Wave Detector ◽  
The Earth ◽  
Spark Gap ◽  
Wireless Telegraph ◽  
Formed Part

In a communication published in the ‘Proceedings,’ Mr. Marconi has given the results observed when a straight horizontal conductor is substituted for the usual vertical conductor employed as a transmitter or receiver at a wireless telegraph station. The object of the following note is to consider the theory of such an arrangement, or at any rate one aspect of it. The receiver, as being the more important, will be considered first. Let AB (fig. 1) represent the horizontal receiver, consisting of a straight conductor having the end A connected to a spark-gap CC 1 or other wave-detector. The electric oscillations in AB can be represented by a distribution of Hertzian oscillators along AB, and, if L denotes the current strength at any point of AB, it must satisfy the conditions L= 0 at B, the free end, and d L/ ds = 0 at A, since the electric force perpendicular to AB at A must vanish. If the distance of AB from the earth is not too small, the effect of the oscillations belonging to the image in the earth of AB on those in AB may be neglected, the radiation from the free end B will be approximately symmetrical with respect to AB, and the oscillations in AB are then approximately the same as if BA formed part .of a semi-infinite straight conductor in which a system of oscillations is being maintained, B being the free end and A. the first node from the free end; the wave-length of these oscillations is very approximately five times the length of AB, and therefore the receiver is of maximum efficiency when its length is one-fifth of the length of the transmitted wave, a result observed by Marconi. When the distance of AB from the earth is so small that the effect of the oscillations in the image of AB in the earth on the oscillations in AB is not negligible, the radiation from the free end B will not be symmetrical with respect to AB, but may be taken as being approximately symmetrical with respect to some line through B making an angle with BA; the wave-length of the oscillations in AB is therefore equal to the wave-length of the oscillations in a bent conductor joining AB; that is greater than five times the length of AB, and, therefore, in this case the receiving conductor has its maximum efficiency when its Length is somewhat less than one-fifth of the length of the transmitted wave, result also observed by Marconi. To examine the effect of the orientation of the receiver, consider a straight conductor BAB' twice the length of AB (fig. 2) and its image B 1 A 1 B 1 ' in the horizontal plane, A and A 1 being their middle points respectively.

Carbamate and organophosphorus sprays as alternatives to DDT to control red-legged earth mites (Halotydeus destructor and Penthaleus major)

1965 ◽  
Vol 5 (16) ◽  
pp. 68 ◽  
Author(s):  
WE Wright
Keyword(s):  
Active Ingredient ◽  
Mite Species ◽  
Effective Control ◽  
Animal Products ◽  
Halotydeus Destructor ◽  
Mite Control ◽  
Organophosphorous Compounds ◽  
Low Volume

Four experiments, two conducted in 1962 and two in 1963, are described. Low volume applications of two carbamates, eight organophosphorous compounds, and a quinoxaline miticide were tested for their value in controlling the two species of red-legged earth mites, Halotydeus destructor (Tucker) and Penthaleus major (Duges) alongside the standard DDT treatment of four ounces active ingredient an acre. Two of the organophosphorous compounds, namely azinphos ethyl and 'Imidan' applied at half an ounce active ingredient an acre, were shown to give effective control of both mite species for at least five weeks and can now be recommended as alternative mite control treatments that would eliminate the risk of contamination of meat or animal products by undesirable residues. Since DDT at 2 oz active ingredient an acre gave very effective mite control, this lower dosage may- be useful in lessening the residue risk.

Delivery of Low-Volume Road in Pilbara Region of Western Australia by Alliance Contracting

2011 ◽  
Vol 2203 (1) ◽  
pp. 203-210 ◽  
Author(s):  
Geoffrey Cocks ◽  
Jacqueline Scott ◽  
Terry Pearce ◽  
Mark Hazebroek ◽  
Paul Fisher ◽  
...  
Keyword(s):  
Western Australia ◽  
Low Volume

The intial and residual effects of superphosphate and rock phosphate for sorghum on a lateritic red earth

1963 ◽  
Vol 14 (6) ◽  
pp. 785 ◽  
Author(s):  
W Arndt ◽  
GA McIntyre
Keyword(s):  
Rock Phosphate ◽  
Residual Effects ◽  
Residual Value ◽  
Clay Loam ◽  
Initial Value ◽  
Long Run ◽  
Highly Effective ◽  
Red Earth ◽  
Sorghum Production

The initial and residual effects of superphosphate and rock phosphate with sorghum were recorded on Tippera clay loam a lateritic red earth at Katherine, N.T. Both forms of phosphate were highly effective as initial broadcast applications and as residues. Initially, superphosphate was superior to rock phosphate on a weight per acre basis. For superphosphate the residual value left after 1 year was 50% of the initial value, and after 7 years about 8%. For rock phosphate the residual value after 7 years was about 66–70% of the initial value. The data have been extrapolated to give rough estimates of the value to complete exhaustion of the residue. These estimates suggest that for both superphosphate and rock phosphate, regular annual dressings of 1 cwt and of 2 cwt will give in the long run at least 80% and 95% respectively of the sorghum production possible with phosphate not limiting.

No longer a west-side story – pesticide resistance discovered in the eastern range of a major Australian crop pest, Halotydeus destructor (Acari: Penthaleidae)

2018 ◽  
Vol 69 (2) ◽  
pp. 216 ◽  
Author(s):  
James L. Maino ◽  
Matthew Binns ◽  
Paul Umina
Keyword(s):  
Western Australia ◽  
Organophosphorus Pesticides ◽  
South Australia ◽  
Resistance Testing ◽  
Halotydeus Destructor ◽  
West Side Story ◽  
Redlegged Earth Mite ◽  
Important Pest ◽  
Control Failure ◽  
Upper South

The redlegged earth mite, Halotydeus destructor (Tucker) (Acari: Penthaleidae), is an important pest of pastures, broad-acre crops, and vegetables across southern Australia. Populations of H. destructor in Western Australia have been known to be resistant to pyrethroid and organophosphorus pesticides since 2006 and 2014, respectively. Resistant populations are currently widespread across Western Australia’s southern growing region but have, until now, remained undetected in the large south-eastern Australian range of H. destructor, despite ongoing resistance screening since 2006. Following reports of a field control failure in the Upper South East district in South Australia in 2016, resistance testing determined this South Australian population was resistant to pyrethroid and organophosphorus pesticides. The levels of resistance discovered were similar to resistant H. destructor populations in Western Australia, which are associated with chemical control failures. This work confirms for the first-time that pesticide resistant populations of H. destructor are no longer isolated to Western Australia.

The effect of insecticide treatment on the yield and botanical composition of sown pastures in Western Australia

1963 ◽  
Vol 3 (8) ◽  
pp. 39 ◽  
Author(s):  
MMH Wallace ◽  
JA Mahon
Keyword(s):  
Western Australia ◽  
Dry Matter ◽  
Response To Treatment ◽  
Botanical Composition ◽  
Stocking Rate ◽  
Careful Selection ◽  
Average Response ◽  
Insecticide Treatment ◽  
Halotydeus Destructor ◽  
Selection Of

The yield and botanical composition of established, sown pastures were measured after applying insecticides to control the red-legged earth mite. Halotydeus destructor (Tuck.), the lucerne Flea, Sminthurus viridis (L.) and the webworm, Talis spp. The response to treatment depended upon the pest involved, the numbers present, and the vigour of the pasture. Control of H. destructor resulted in an average response of 3.9. cwt an acre of extra dry matter in the spring. To consume this, it is sugested that stocking rate should be increased by about 1/4 sheep per acre. This could be raised to 1/3 sheep per acre by careful selection of treatment areas. Slightly greater responses, up to perhaps 1/4 sheep per acre, can be expected when S. viridis is plentiful. Heavy webworm attack reduced carping capacity on average about one sheep per acre. The economics of insecticide treatment are examined in the light of these results. A formula is given whereby the farmer can calculate the likely return from treatment on his own property. It is concluded that in a large number of cases treatment is near the borderline of profitability. Farmers should make certain that insecticide treatment is the best way of spending their money. Having decided to use insecticides they should (a) treat only those areas where obvious damage is being done and avoid any blanket spraying programme and (b) ensure that some positive use is made of the increased herbage following treatment.

scholarly journals The Process of Ultra Low-Volume Seed Etching by an Experimental Device

2021 ◽  
Vol 346 ◽  
pp. 03114
Author(s):  
Sergey Papusha ◽  
Filipp Kozhura ◽  
Valeria Zhadko
Keyword(s):  
Seed Treatment ◽  
Feeding Tube ◽  
Experimental Device ◽  
Pneumatic System ◽  
Maximum Efficiency ◽  
Compressor Unit ◽  
Seed Material ◽  
Low Volume ◽  
Electricity Network

The main way to protect plants from diseases and pests is the treatment of seed material with pesticides. To achieve maximum efficiency from complex seed treatment, it is necessary to evenly distribute the drug over the surface of all available seeds. One of the conditions for operation of the etcher is the possibility of connecting to the compressor unit and the electricity network. The performance of the sprayer was studied depending on the pressure in the pneumatic system of the spraying device and the diameter of the feeding tube.

scholarly journals Solar Panel Efficiency Calculation using Incremental Conductance Algorithm

2019 ◽  
Vol 8 (3) ◽  
pp. 3761-3763
Keyword(s):  
Maximum Energy ◽  
Maximum Amount ◽  
Maximum Efficiency ◽  
Solar Panels ◽  
Good Efficiency ◽  
Renewable Source ◽  
Incremental Conductance ◽  
The Earth ◽  
Solar Tracker ◽  
Tracking Point

Solar energy is a vital renewable source of energy in India. To extract and utilize this renewable source of energy photovoltaic solar panels are used. To gather the maximum amount of energy a good efficiency solar panels are used. The maximum efficiency is achieved when the maximum irradiation from the sun is received by the earth. The irradiation and temperature are proportional with time, a solar tracker should be developed and positioned to extract the maximum energy with respect to time. This paper is aimed to find the maximum tracking point and the maximum efficiency using Incremental Conductance (IC) algorithm. The IC method is the simplest and the easiest way to find the efficiency of the panels with respect to the time throughout the day.

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