phytotoxicity symptoms were observed from CaCl 2 application (data not shown). Fig. 7. ( A ) Fresh weight, ( B ) dry weight, ( C ) and tipburn rating of Lactuca sativa ‘Green Butter’ at harvest after twice-a-week foliar spray applications of calcium chloride
Uttara Samarakoon, Jack Palmer, Peter Ling, and James Altland
Bruce W. Wood
(depending on tree and orchard situation) after the ground application may still result in the need for foliar sprays. Application through trenching, even in acidic soils, is generally inferior to broadcast applications, although it can be efficacious and
Graham H. Barry and Smit le Roux
different times of application are summarized in Table 1 . In addition to the foliar spray applications, individual ‘Eureka’ lemon fruit and fruit plus leaves were dipped on 4 May 2005 in 200 and 400 mg·L −1 ProCa solutions because the bulk of the lemon
T. Casey Barickman, Dean A. Kopsell, and Carl E. Sams
. For example, de Freitas et al. (2011) found that foliar spray applications of ABA decreased total leaf Ca accumulation per plant when observed in plants 12 to 45 d after pollination. In comparison, the current study examined total Ca accumulation in
Holger Weichert, Stefanie Peschel, Moritz Knoche, and Dieter Neumann
, spray application of the salts investigated so far is prohibitive for ecotoxicological reasons. However, because the mechanistic basis underlying this effect is now identified, the search for the effective and acceptable ‘silver bullet’ can now begin
Ockert P.J. Stander, Graham H. Barry, and Paul J.R. Cronjé
development in the current season, flowering in the next season, or both—the two main determinants of fruit load in ‘Nadorcott’ mandarin. Apart from some anomalies, concentrations of macronutrients in leaves were unaffected by de-fruiting and foliar spray
Steven A. Tjosvold, Meng-Jen Wu, and Michael S. Reid
Potted miniature roses (Rosa × hybrids L. `Belle Sunblaze') held after production in simulated home conditions (21C, continuous fluorescent light) yellowed prematurely, flower buds and leaves abscised, and flower buds failed to open. These symptoms were accelerated when the plants were exposed to low concentrations (1 μl·liter-1) of ethylene in the absence of inhibitors. Spray application of 100 μl BA/liter reduced leaf yellowing but had no significant effect on flower opening or bud abscission. Spray application of 1 mm silver thiosulfate (STS) strongly promoted flower display but did not prevent leaf yellowing. A combined BA and STS treatment greatly improved the postproduction quality of rose plants, particularly if applied 1 day before harvest. Chemical name used: benzyladenine (BA).
Jayesh Samtani, Gary Kling*, and David Williams
Conventional herbicide applications to container-grown landscape plants, often requires multiple spray applications of herbicides in a growing season and presents problems such as non-uniform application, leaching, run-off, environmental pollution, worker exposure and phytotoxicity to the landscape plants. The use of an organic herbicide carrier could help reduce some of the problems associated with spray applications. Landscape-leaf waste pellets were evaluated as a preemergent herbicide carrier for container-grown landscape plants. Isoxaben, prodiamine and pendimethalin were applied to Chrysanthemum × grandiflorum `Lisa', Euonymus fortunei `Coloratus' and Spiraea japonica `Neon Flash', at rates of 1.12, 2.25, and 2.25 kg·ha-1 active ingredient, respectively, with either water or landscape leaf waste pellets as a carrier. Portulaca oleracea, Senecio vulgaris, and Setaria faberi were seeded following treatment application. Visual ratings on efficacy and photoxicity to landscape plants, and shoot fresh and dry biomass were determined for both weeds and crop plants. Landscape leaf pellets served as an effective carrier for application of prodiamine and pendimethalin and combinations of these herbicides with isoxaben in controlling weeds. Leaf waste pellets as a carrier produced equivalent weed control and phytotoxicity ratings to conventional spray application of these herbicides, on both Chrysanthemum and Euonymus. The pellets did not make a consistently effective carrier for the application of isoxaben alone. Application of herbicides on leaf pellets could result in more uniform herbicide applications, minimize loss of herbicides to the environment and reduce the risk of herbicide contact with nursery workers.
Peter M.A. Toivonen and Pascal Delaquis
Use of sprays to sanitize and treat apple (Malus ×domestica) slices helps to reduce the potential for cross-contamination that can occur when treatments are done in dip tanks. This research examined several factors that may affect the efficacy of spray treatments: 1) spray volume; 2) efficacy of spray application of anti-browning solution (ABS) compared with dipping; 3) effect of slice density during spraying; and 4) effect of the addition of an antimicrobial compound, vanillin, on microbiologically associated browning. Low-volume sprays (36-50 mL·kg-1 slices) of ABS gave maximal control of browning and this was equivalent to the control afforded by a 2-minute dip in the ABS. Spray application resulted in significant reduction in incidence and severity of microbiologically associated “secondary browning” as compared with dip application. However, if more than one layer of slices were present on the support mesh during the spray treatment, then secondary browning increased. This was attributed to potential cross-contamination between layers of apples in the spray treatment. Addition of vanillin into the ABS resulted in a 50% reduction of the incidence of “secondary browning.” Low-volume spray applications of ABS can be managed such that the microbiologically associated “secondary browning” is much lower than possible with dip application.
Raymond A. Cloyd
group of pesticides to reduce labor costs associated with spray applications and to potentially improve control of arthropod pests (synergism), they need to be cautious when tank mixing so as to avoid problems associated with antagonism, incompatibility