Effectiveness of spring spraying targeting diapause egg production for controlling redlegged earth mites and other pests in pasture

2008 ◽  
Vol 48 (8) ◽  
pp. 1118 ◽  
Author(s):  
Jane M. C. Gower ◽  
Ary A. Hoffmann ◽  
Andrew R. Weeks
Keyword(s):  
Chemical Control ◽  
Egg Production ◽  
Control Level ◽  
Growing Season ◽  
Economic Damage ◽  
Halotydeus Destructor ◽  
Redlegged Earth Mite ◽  
Invertebrate Pests ◽  
General Method

Earth mites are a complex of related species introduced into Australia in the early part of last century that cause economic damage to crops, especially canola, and to pastures. A general method of chemical control aimed at interrupting the life cycle at the most effective stage, by spraying in the spring before the mites enter diapause, has recently been adopted for controlling earth mites, particularly the redlegged earth mite Halotydeus destructor (Tucker). Here we use paired-paddock treatments and field enclosures to test the effectiveness of this method on pest populations of H. destructor as well as on other pests over two seasons at multiple pasture sites in Victoria. Halotydeus destructor numbers at the start of the winter growing season were suppressed by up to 85%, but this control level was not sustained. The numbers of H. destructor and other pests were similar to or higher than those in the unsprayed areas by spring. Spring spraying is, therefore, a useful means of suppressing H. destructor in early autumn, but its effects disappear relatively quickly over time in Victoria. This strategy also has little impact on the control of the blue oat mite Penthaleus major (Duges) and other phytophagous invertebrate pests.

Efficacy of Live Vaccines and Specific Prevention in Chicken Infectious Bronchitis

2020 ◽  
Keyword(s):  
Egg Production ◽  
Live Weight ◽  
Economic Damage ◽  
Feed Conversion ◽  
Local Immunity ◽  
Effective Prevention ◽  
Live Vaccines ◽  
Infectious Bronchitis ◽  
Variant Strain

Infectious bronchitis of chickens (IBC) is a highly contagious disease characterized by damage to the respiratory tract. Adult chickens exhibit respiratory symptoms, a 10-50% decrease in egg production, discoloration of the eggshell, deformation of the shell, and a deterioration in the marketability and breeding quality of eggs. The circulation of variant strains in poultry farms of the Russian Federation causes a significant decrease in egg production and the quality of the eggs obtained, causing significant economic damage to industrial poultry farming. The study aimed to presents materials and methods for the industrial and efficient use of live-vaccines against infectious bronchitis of hens from a variant strain. After the use of a live vaccine against infectious bronchitis of chickens from a variant strain, the development, live weight of chickens, and feed conversion during the rearing period were within the standard parameters. in present study, the safety for the growing period with a planned 97.6% was 98.8-98.9%. The uniformity of the herds when transferred to hen - hen was 94-95%. When carrying out immunoprophylaxis of IBS, local immunity is important, which can be ensured using a live spray vaccine - a method starting from the day old. When establishing circulation in the economy of variant strains of IBC virus, it is necessary to introduce vaccination against the variant strain into the scheme of treatment and preventive measures. The research results allow us to conclude that, for the effective prevention of chicken infectious bronchitis, immunization against IBS from variant strains should be introduced into the vaccine prevention scheme.

PERFORMANCE OF DWARF BROILER BREEDERS IN LAYING CAGES AND FLOOR PENS AND OF NORMAL BREEDERS IN FLOOR PENS

1975 ◽  
Vol 55 (4) ◽  
pp. 741-747 ◽  
Author(s):  
J. H. STRAIN ◽  
A. P. PILOSKI
Keyword(s):  
Body Weight ◽  
Egg Production ◽  
General Pattern ◽  
Female Offspring ◽  
Male Offspring ◽  
Production Cycle ◽  
Feed Conversion ◽  
Broiler Breeders ◽  
Feed Costs

Dwarf broiler breeders in single-bird cages (DC), in floor pens (DF) and normal broiler breeders in floor pens (NF) were compared for their own and their offspring’s performance. No differences were observed in rate of egg production at 147–329 days of age between the NF and DF birds (48 vs. 47%) whereas the DC birds laid at the rate of 40%. Hen-housed egg numbers for the same period followed the same general pattern (NF, 81; DF, 82; DC, 70 eggs/bird). DF and DC birds consumed less feed per dozen eggs than the NF birds (3.4 vs. 4.3 kg/doz). Egg weights in the early part of the production cycle were not significantly different among the groups but at 294 days of age the normal birds laid larger eggs than the dwarfs (65 vs. 62 g). Dwarfs in cages reached 50% production earlier than the DF or NF birds. Female offspring from the three groups grew at the same rate and weighed 1.7 kg at 56 days of age but there were significant differences in feed conversion (NF, 2.46; DF, 2.43; DC, 2.53 kg/kg body weight produced). Male offspring had small but not statistically significant differences in body weight at 56 days (NF, 2.16; DF, 2.12; DC, 2.09 kg) or feed conversion (NF, 2.30; DF, 2.29; DC, 2.34 kg/kg body weight). Mortality in the offspring ranged from 2.7 to 9.2% but did not differ significantly. Income over feed costs per broiler started did not differ from the three groups regardless of the meat price – feed price combination considered. However, when profit was computed on a breeder hen basis, the DF females were more profitable than either the NF or DC females.

scholarly journals Strategies for control of the redlegged earth mite in Australia

2008 ◽  
Vol 48 (12) ◽  
pp. 1506 ◽  
Author(s):  
T. J. Ridsdill-Smith ◽  
A. A. Hoffmann ◽  
G. P. Mangano ◽  
J. M. Gower ◽  
C. C. Pavri ◽  
...  
Keyword(s):  
Control Strategies ◽  
Field Trials ◽  
Effective Control ◽  
Synthetic Pyrethroids ◽  
Halotydeus Destructor ◽  
Mite Control ◽  
Redlegged Earth Mite ◽  
Single Well ◽  
Plant Seedlings ◽  
Control Package

The redlegged earth mite, Halotydeus destructor, continues to be an intractable pest causing damage to most crop and pasture species in southern Australia. H. destructor feed on all stages of plants, but particularly damage seedlings in autumn. Research has aimed to develop new controls based on a better understanding of the biology and ecology of this pest. Chemicals remain the key tool to control H. destructor, despite the recent appearance of resistance to synthetic pyrethroids. A control package, Timerite, has been developed by which a single well-timed spray in spring can prevent H. destructor from developing diapause eggs. Field trials show this strategy provides effective control of H. destructor the following autumn, and protects plant seedlings, although mite populations build up again during winter. Non-chemical control strategies include grazing, the use of tolerant plants such as cereals, resistant legume cultivars and avoiding rotations where favourable host plants are available in the year before growing susceptible crops such as canola. Natural enemies can assist in mite control, and their numbers can be enhanced by methods including increasing landscape features like shelterbelts. Interspecific competition can occur between H. destructor and other pest mites, but the extent to which these interactions influence the structure of pest communities under different management regimes remains to be investigated.

Lophodermium oxycocci. [Descriptions of Fungi and Bacteria].

2005 ◽  
Author(s):  
D. W. Minter
Keyword(s):  
British Columbia ◽  
Czech Republic ◽  
New Jersey ◽  
Geographical Distribution ◽  
Chemical Control ◽  
Vaccinium Macrocarpon ◽  
Economic Damage ◽  
Twig Blight

Abstract A description is provided for Lophodermium oxycocci. Information is included on the disease, cranberry twig blight, caused by the organism, that can cause serious economic damage to commercial cranberry crops in Oregon and Washington. Some information on cultural and chemical control is given, along with details of its transmission, geographical distribution (Canada (British Columbia), USA (Alaska, Maine, Massachusetts, Michigan, New Jersey, Oregon and Washington), Russia, Czech Republic, Finland, France, Germany, UK, Poland, Sweden and Ukraine) and hosts (Vaccinium macrocarpon, Vaccinium sp. and V. oxycoccus).

Chemical Control of Reed Canarygrass on Irrigation Canals

Weed Science ◽  
1968 ◽  
Vol 16 (4) ◽  
pp. 465-468 ◽  
Author(s):  
J. M. Hodgson
Keyword(s):  
Chemical Control ◽  
Trichloroacetic Acid ◽  
Poa Pratensis ◽  
Ammonium Thiocyanate ◽  
Growing Season ◽  
Kentucky Bluegrass ◽  
Early Winter ◽  
Irrigation Canals ◽  
Reed Canarygrass ◽  
Irrigation Project

From 1962 to 1967, we evaluated herbicides for control of natural infestations of reed canarygrass (Phalaris arundinacea L.) on canal banks of the Huntley, Montana irrigation project. Two,2-dichloropropionic acid (dalapon) and 3-amino-1,2,4-triazole ammonium thiocyanate (hereinafter referred to as amitrole-T) controlled reed canarygrass. These herbicides were compared with a number of others. Spring foliage treatments with a combination of amitrole-T at 2 1b/A and dalapon or trichloroacetic acid (TCA) at 5 or 10 1b/A were more effective than amitrole-T at 4 1b/A. Amitrole-T was more tolerant to fine grasses such as Kentucky bluegrass (Poa pratensis L.) or redtop (Agrostis alba L.) than dalapon and in some situations it was more desirable than dalapon. Dalapon and TCA were more effective as late fall or early winter treatments to control reed canarygrass during the following growing season. Rates of 20 or 40 1b/A controlled the grass for one season even at the water's edge where it is usually more persistent. At 5 to 10 1b/A, 2,3,5-trichloro-4-pyridinol (pyriclor) controlled reed canarygrass, and it also was effective at 2 1b/A with 2 1b/A of amitrole-T.

Effects of Weed Control and Irrigation on the Growth of Young Pecans

1990 ◽  
Vol 4 (4) ◽  
pp. 892-894 ◽  
Author(s):  
Michael G. Patterson ◽  
Glenn Wehtje ◽  
William D. Goff
Keyword(s):  
Weed Control ◽  
Tree Growth ◽  
Chemical Control ◽  
Growing Season ◽  
Control Effect ◽  
Carya Illinoensis ◽  
Maximum Increase ◽  
Tree Diameter ◽  
The Third ◽  
Selective Chemical

The effect of irrigation and weed control by various mechanical and chemical means was evaluated over a 4-yr period on newly planted pecans [Carya illinoensis(Wang.) K. Koch]. Weed control effect on tree growth became evident in the second growing season, and became more pronounced after the third and fourth season. After the fourth season, the maximum increase in tree diameter (384%) was achieved with comprehensive, herbicide-based weed control. Mowing provided a 224% increase, which was equivalent to the untreated (229%). Disking and selective chemical control of grass weeds resulted in 339 and 292% increase, respectively. Cumulative increase in tree diameter was 316 and 271% with and without irrigation, respectively.

scholarly journals The effect of biological and chemical control agents on the health status of the very early potato cultivar Rosara

2015 ◽  
Vol 55 (4) ◽  
pp. 389-395
Author(s):  
Bożena Cwalina-Ambroziak ◽  
Marta Maria Damszel ◽  
Małgorzata Głosek-Sobieraj
Keyword(s):  
Biological Control ◽  
Health Status ◽  
Chemical Control ◽  
Potato Cultivar ◽  
Growing Season ◽  
Control Treatment ◽  
In Vitro Test ◽  
Ne Poland ◽  
Vitro Test

Abstract The external appearance and quality of table potatoes are determined, among other factors, by the health status of the plants during the growing season. Chemical control methods are often combined with biocontrol agents to effectively fight potato pathogens. Potatoes of the very early cultivar Rosara were grown in experimental plots. The plots were located in Tomaszkowo (NE Poland, 2007-2009). The experiment involved the following treatments: 1) biological control − mycorrhizal Glomus spp. inoculum was applied to the roots, − tubers were dressed and plants were sprayed with Polyversum three times during the growing season, 2) chemical control - at two-week intervals, plants were sprayed with the following fungicides: Infinito 687.5 SC and Tanos 50 WG, Valbon 72 WG and Tanos 50 WG. In the control treatment, potato plants were not protected against pathogens. During the growing season, the severity of late blight and early blight was evaluated on a nine-point scale. The composition of fungal communities colonising potato stems was analysed. The fungistatic properties of the fungicides used in the field experiment were evaluated in an in vitro test. The symptoms of infections caused by Phytophthora infestans and Alternaria spp. were significantly reduced in the treatment which used the integrated chemical and biological control. The least diverse fungal community was isolated from fungicide-treated plants. In the in vitro test, fungicides at all analysed concentrations inhibited the linear mycelial growth of selected pathogens.

Experimental angiotensin II hypertension

1980 ◽  
Vol 239 (3) ◽  
pp. H391-H398 ◽  
Author(s):  
D. B. Young ◽  
R. H. Murray ◽  
R. G. Bengis ◽  
A. K. Markov
Keyword(s):  
Cardiac Output ◽  
Angiotensin Ii ◽  
Arterial Pressure ◽  
Blood Volume ◽  
Vascular Tone ◽  
Control Level ◽  
Circulatory System ◽  
Question Mark ◽  
Control Value

The mechanisms by which angiotensin II (AII) produces hypertension was studied in a group of 13 large dogs maintained on a Na intake of 200 meq/day. AII was infused at 10 ng x kg-1 x min-1 iv for 8 days. Arterial pressure increased from the control level of 98 +/- 3 to 160 +/- 7 mmHg and cardiac output fell significantly from the control value of 3.4 +/- 0.2 to 2.4 +/- 0.2 and 2.6 +/- 0.1 l/min on the 5th and 8th days of AII infusion. Mean circulatory filling pressure (MCFP) rose from the control mean of 9.5 +/- 0.5 to 11.6 +/- 0.9 (P < 0.05) and 12.6 +/- 0.6 mmHg (P inverted question mark 0.05) on the 5th and 8th day of infusion. On the 1st day of AII infusion, approximately 70 meq Na was retained; this retention persisted until the 4th day, when a marked natriuresis returned the dogs to Na balance. 22Na space increased slightly (P < 0.05) during the early part of the study, but fell back to the control level by the 5th day of infusion. Blood volume was unchanged throughout the study. The marked increase observed in MCFP with unchanged blood volume indicates that the unstressed volume or compliance of the circulatory system must have decreased. In this form of hypertension, the increase in arterial pressure was achieved without volume expansion and cardiac output elevation, but with large initial increases in arterial and venous vascular tone.

Weed Survey System used in Saskatchewan for Cereal and Oilseed Crops

Weed Science ◽  
1985 ◽  
Vol 33 (1) ◽  
pp. 34-43 ◽  
Author(s):  
A. Gordon Thomas
Keyword(s):  
Growing Season ◽  
Agricultural Extension ◽  
Sampling Procedure ◽  
Distribution Maps ◽  
Agricultural Extension Service ◽  
Polygonum Convolvulus ◽  
Green Foxtail ◽  
Survey System ◽  
Weed Survey

A weed survey system methodology was developed and used annually for 4 yr in the province of Saskatchewan. Based on a stratified random sampling procedure, fields were selected in wheat (Triticum aestivumL.), barley (Hordeum vulgareL.), oat (Avena sativaL.), rye (Secale cerealeL.), rape (Brassica napusL.,Brassica campestrisL.), and flax (Linum usitatissimumL.) crops. The boundaries of the 43 agricultural extension districts in the province formed the strata. The provincial agricultural extension service provided staff to conduct the survey. Computer processing of the data enabled reports, containing summary tables and distribution maps, to be distributed to extension, research, and industry personnel within 3 months after completion of the field survey. The field surveys were conducted late in the growing season before harvest commenced; hence, the weed populations consisted of species that had been present during the early part of the growing season and may have contributed to yield losses. During the 4 yr of the survey, weeds were counted in 4423 fields. Of the 164 species recorded, 97 species occurred in more than three fields. Only 29 species were encountered frequently in the fields. Green foxtail [Setaria viridis(L.) Beauv. # SETVI), wild buckwheat (Polygonum convolvulusL. # POLCO), and wild oat (Avena fatuaL. # AVEFA) were the top three species based on a ranking system using a measure called relative abundance.

Water system recovery after two consecutive years of extreme droughts

2020 ◽  
Author(s):  
Janneke Pouwels ◽  
Perry de Louw ◽  
Dimmie Hendriks ◽  
Joachim Hunink
Keyword(s):  
The Netherlands ◽  
Recovery Period ◽  
Water System ◽  
Growing Season ◽  
Water Model ◽  
Economic Damage ◽  
Integrated Water Management ◽  
Groundwater Levels ◽  
Multi Scale ◽  
Large Soil

&lt;p&gt;In large parts of Europe, the year 2018 is known as an extremely dry year. In the Netherlands this 2018 drought caused over 1 billion euros of economic damage to different sectors like agriculture, nature, industry, shipping, infrastructure and buildings. A large part of economic damage was due to extreme low groundwater levels and large soil moisture deficits. Many streams stopped flowing since groundwater levels were too low to feed the streams. The extreme low rainfall amount, in combination with above average high potential evaporation rates, caused a precipitation deficit of 300 mm in the growing season, which is normally less than 100 mm. In 2019, the year after, the spatial variability of precipitation in the Netherlands was high with only a precipitation deficit in the growing season of a few tens of millimeters in the low-lying western part of the Netherlands. However, in the higher sandy areas in the south and east part of the Netherlands, the precipitation deficit was again extreme and more than 240 mm. For the higher sandy areas this was the second dry year in a row and the question arose what the effect of two consecutive dry years on the water system was and how fast it may recover.&lt;/p&gt;&lt;p&gt;This question has been analyzed by applying an integrated nationwide groundwater and surface water model (De Lange et al., 2014). The model results showed that for the higher sandy areas, groundwater levels and stream discharges were even lower in the second than in the first dry year. In addition, the recovery period of the groundwater system after two extremely dry years was examined by simulating ten &quot;normal&quot; years with average precipitation and evaporation patterns following the two extremely dry years. The model results showed a large spatial variation in groundwater level recovery.&amp;#160; In the first recovery year groundwater levels increased for most of the area, except for the higher-lying sandy areas lacking any surface waters (ditches and streams), like the largest Dutch forest area, the Veluwe. In these slow-responding regional recharge areas, groundwater levels are still dropping. For the central part of the Veluwe, this dropping continues until the seventh recovery year.&amp;#160; The model results showed that two consecutive dry years have a large impact on the water system, and that full recovery of groundwater levels and stream discharges may take 2 to 4 years in most of the sandy areas, yet the recovery of the highest parts may take up to 7 to 8 years.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;De Lange, W.J., Prinsen, G.F., Hoogewoud, J.C., Veldhuizen, A.A., Verkaik, J., Oude Essink, G.H.P., Van Walsum, P.E.V., Delsman, J.R., Hunink, J.C., Massop, H.Th.L., Kroon T. (2014). An operational, multi-scale, multi-model system for consensus-based, integrated water management and policy analysis: The Netherlands Hydrological Instrument. Accepted for publication in Environmental Modelling &amp; Software&lt;/p&gt;

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