User manual for SAFE (Select Application date For Evaluation) to support the use of the GEM scenarios for cultivations in glasshouses

SUMMARYBlack polyethylene tunnels were used to subject Armore and Missionary strawberry cultivars to 21 short-day inductive cycles at either full bloom (7–28 May) or fruit swelling (1–21 June) stages. Regardless of application date, treatments induced a second bloom 8–10 weeks after treatment in both cultivars. The second crop of Armore was as large as the first, but Missionary produced only a small second crop that would not be worth commercial harvesting. Covering plants with black polyethylene reduced the vitamin C content of the first-crop fruits of Armore without affecting yield, while Missionary responded in an opposite way. Treating plants at full bloom hastened the ripening of the first crop of both cultivars by about 1 week and resulted in a larger second crop than was obtained by the later treatment.

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Effect of Application Date on Absorption of 15Nitrogen by Highbush Blueberry

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.122.3.422 ◽

1997 ◽

Vol 122 (3) ◽

pp. 422-426 ◽

Cited By ~ 12

Author(s):

Philip A. Throop ◽

Eric J. Hanson

Keyword(s):

Ammonium Sulfate ◽

Root Zone ◽

Vaccinium Corymbosum ◽

N Availability ◽

Active Growth ◽

Fruit Maturity ◽

Application Date ◽

Highbush Blueberries ◽

Moisture Conditions ◽

Similar Soil

Rates of absorption of 15N-enriched ammonium sulfate by young `Bluecrop' highbush blueberries (Vaccinium corymbosum L.) were compared following applications on six dates between late April and September. Ammonium sulfate solutions containing 2.1 g N (10.2 atom % 15N) were dripped directly into the root zone of single bushes. Soil covers and irrigation were used to maintain similar soil moisture conditions during treatment periods. Treated bushes from each application date were excavated after 2 weeks of exposure and separated into roots, stems, and current season's growth (new shoots, leaves, fruit). Tissues were dried, weighed, and analyzed for 15N and 14N by mass spectrometry. Soils were also analyzed for labeled and nonlabeled N. Bushes treated in late May, June, and July absorbed a greater percentage of applied N (6% to 9%) than bushes treated in April, August, or September (1% to 3%). Absorption of N appeared to be affected more by the demand of the plants than soil N availability. Plants absorbed N most efficiently during active growth between late bloom and fruit maturity.

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Evaluation of Phytotoxicity of Diazinon and Captan Formulations on Highbush Blueberries

HortTechnology ◽

10.21273/horttech.10.2.308 ◽

2000 ◽

Vol 10 (2) ◽

pp. 308-314 ◽

Cited By ~ 3

Author(s):

Sridhar Polavarapu

Keyword(s):

Untreated Control ◽

Vaccinium Corymbosum ◽

Highbush Blueberry ◽

Application Date ◽

Highbush Blueberries ◽

Time Of Harvest ◽

Over Time

A common practice in highbush blueberry (Vaccinium corymbosum L.) culture is to use combinations of insecticides and fungicides to reduce the number and cost of pesticide applications. In response to apparent phytotoxicity observed in commercial fields that were treated with combinations of diazinon and captan formulations, phytotoxicity of two formulations of diazinon (Diazinon AG600 and Diazinon 50W) and captan (Captan 80WP and Captec 4L) was investigated on highbush blueberries during 1997 and 1998. Phytotoxicity injury similar to injury observed in commercial fields was reproduced in treatments with diazinon and captan mixtures in all experiments. The Diazinon AG600 and Captec 4L mixture was the most severe and caused significantly more phytotoxic-ity to fruit and leaves than individual treatments of Diazinon AG600, Captec 4L or untreated control. Separation of diazinon and captan applications by 8 h significantly reduced phytotoxicity compared to mixture treatments. Injured fruit and leaves recovered over time and most treatments showed only a mild injury at the time of harvest. Phytotoxicity on fruit and leaves caused by Diazinon AG600 and Captec 4L mixture was significantly affected by application date with the earliest application causing the greatest injury. These data indicate that diazinon and captan mixtures cause phytotoxicity on highbush blueberries and therefore the two should not be applied in combination.

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Improving IPM Decision Support in Vegetable Crops through Weather-based Disease Advisories

HortScience ◽

10.21273/hortsci.40.4.1110d ◽

2005 ◽

Vol 40 (4) ◽

pp. 1110D-1110

Author(s):

Albert Sutherland ◽

John Damicone ◽

Rafal Jabrzemski ◽

Stdrovia Blackburn

Keyword(s):

Decision Support ◽

Site Selection ◽

Historical Data ◽

Disease Outbreak ◽

Cultural Practice ◽

Weather Data ◽

Vegetable Crops ◽

White Rust ◽

Oklahoma Mesonet ◽

Application Date

Weather-based disease advisories have allowed vegetable producers to optimize their fungicide applications. These models typically use only past weather data to identify times of potential disease outbreak. The Oklahoma Mesonet has developed a new Spinach White Rust Advisory that improves grower disease decision support by combining forecast, current, and past weather data in calculating infection periods. The decision-support component issues initial spray advisories, based on infection hour accumulation from the first true-leaf stage or from a previous fungicide application date for subsequent sprays. The advancement in this model in relation to traditional weather-based disease advisories are: incorporation of an 84-hour forecast, hourly model recalculation, cultural practice customization, user site selection from any of 110+ statewide sites, and immediate access to detailed historical data. The model is available on the Oklahoma Mesonet AgWeather website (http://agweather.mesonet.org).

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Timing of Cut-Stump Herbicide Applications for Killing Hardwood Trees on Power Line Rights-of-Way

Arboriculture & Urban Forestry ◽

10.48044/jauf.2006.016 ◽

2006 ◽

Vol 32 (3) ◽

pp. 118-125

Author(s):

Benjamin Ballard ◽

Christopher Nowak

Keyword(s):

Late Summer ◽

Power Line ◽

Early Spring ◽

Reliable Transmission ◽

Hardwood Trees ◽

Application Techniques ◽

Herbicide Mixtures ◽

Application Date ◽

Cut Stump ◽

Made In

Removal of tall-growing trees on power line rights-of-way is necessary for the safe and reliable transmission of electricity. Cut-stump herbicide treatments have been used at different times of the year to control resprouting and suckering of unwanted hardwood trees on power line corridors in the northeastern United States with varying degrees of success. Growing season applications have typically been thought to be most effective; however, if a high percentage of mortality could also be achieved by selecting an appropriate herbicide mix for early-spring and late-fall applications, vegetation managers would have more flexibility in prescribing and scheduling treatments. The authors evaluated mortality and amount of herbicide applied for April, June, and November using operational-style cut-stump treatments with three herbicide mixes—Accord® + Arsenal®, Garlon 4® + Stalker®, and Pathway®. After 2 years, over 90% mortality was achieved for at least one herbicide mix at all three application dates. Mortality varied by both mix and application date, consistent with herbicide mode of action. In April and June, Accord + Arsenal had lower mortality than Garlon 4 + Stalker or Pathway, but in November, it resulted in slightly higher mortality than the other two mixes. The Garlon 4 + Stalker mix and Pathway had equally high mortality for all treatment dates. Successful use of the cut-stump method in spring through fall may be contingent upon matching herbicide mix to the date of application. These results indicate that Garlon 4 + Stalker or Pathway could be used April through November, but applications with Accord + Arsenal should be made in late summer or fall. These recommendations should be evaluated in other regions and with additional target tree species. The quantity of herbicide used by operational crews varied among application dates and herbicide mixtures and appeared to be strongly influenced by spray equipment and the person applying the herbicide. Minor refinements in application techniques and equipment have the potential to reduce the amount of herbicide used without adversely affecting efficacy, and warrant further consideration.

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Meta-analysis of soybean yield response to foliar fungicides evaluated from 2005 to 2018 in the United States and Canada

Plant Disease ◽

10.1094/pdis-07-20-1578-re ◽

2020 ◽

Author(s):

Yuba Raj Kandel ◽

Catherine L. Hunt ◽

Keith A Ames ◽

Nicholas Arneson ◽

Carl Bradley ◽

...

Keyword(s):

Meta Analysis ◽

Random Effect ◽

The United States ◽

Field Trials ◽

Yield Response ◽

Application Date ◽

Economic Analyses ◽

Meta Analyses ◽

Yield Responses ◽

Spray Control

Random-effect meta-analyses were performed on data from 240 field trials conducted between 2005 and 2018 across nine U.S. states and Ontario, Canada, to quantify the yield response of soybean after application of foliar fungicides at beginning pod (R3). Meta-analysis showed that the overall mean yield response when fungicide was used compared to not applying a fungicide was 2.7% (110 kg/ha). Moderator variables were also investigated and included fungicide group, growing season, planting date, and base yield, which all significantly influenced the yield response. There was also evidence that precipitation from the time of planting to the R3 growth stage influenced yield when fungicide was used (P = 0.059). Fungicides containing a premix of active ingredients from multiple groups (either two or three ingredients) increased the yield by 3.0% over not applying a fungicide. The highest and lowest yield responses were observed in 2005 and 2007, respectively. Better yield response to fungicides (a 3.0% increase) occurred when soybeans were planted not later than 21 May and when total precipitation between planting and the R3 application date was above historic averages. Temperatures during the season did not influence the yield response . Yield response to fungicide was higher (a 4.7% increase) in average yield category (no spray control yield 2878 to 3758 kg/ha) and then gradually decreased with increasing base yield. Partial economic analyses indicated that use of foliar fungicides is less likely to be profitable when foliar diseases are absent or at low levels.

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Wheat (Triticum aestivum) Tolerance to Triallate Applied Spring Preplant-Incorporated

Weed Technology ◽

10.1017/s0890037x00026154 ◽

1990 ◽

Vol 4 (3) ◽

pp. 652-657 ◽

Cited By ~ 2

Author(s):

Patrick M. McMullan ◽

John D. Nalewaja

Keyword(s):

Triticum Aestivum ◽

Spring Wheat ◽

Cultural Factors ◽

Wild Oat ◽

Fresh Weight ◽

Hard Red Spring Wheat ◽

Factors Influencing ◽

Application Date ◽

Solid Stem ◽

Treated Layer

Research was conducted to determine environmental and cultural factors influencing triallate phytotoxicity to hard red spring wheat. Triallate injured ‘Alex’ wheat more than ‘Coteau’ but injury was not influenced by triallate application date. Wild oat control was greater when triallate was applied immediately before seeding compared to 12 d before seeding. Triallate tolerance in wheat did not relate to solid stem characteristic. Injury was highest when wheat was seeded in a 4-cm incorporated triallate layer and least when wheat was seeded below the treated layer. However, triallate injury to wheat was similar at both seeding depths within the 8-cm incorporated triallate layer. Triallate at 1.1 kg ai ha-1reduced wheat fresh weight approximately 33% with a soil at 8 C but over 84% with a soil at 24 C.

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