foliar sprayed with a hand-sprayer at 0.904 mL·ha −1 a.i. TE (0.8 L·ha −1 Primo Maxx; Syngenta Professional Products, Greensboro, NC) every 2 weeks for 9 weeks before drought stress treatment. This treatment was recommended by the manufacturer for
Stephen E. McCann and Bingru Huang
Ockert P.J. Stander, Graham H. Barry, and Paul J.R. Cronjé
by foliar sprays. The Ca and Mg applications were targeted to maintain optimum leaf concentrations of between 35 and 50 mg·g −1 leaf DW for Ca, and 3 and 5.5 mg·g −1 leaf DW for Mg, and supplied as 60 and 22 kg·ha −1 , respectively. Calcium was
Sylvia Cherono, Charmaine Ntini, Misganaw Wassie, Mohammad Dulal Mollah, Mohammad A. Belal, Collins Ogutu, and Yuepeng Han
melatonin treatment, C. arabica plants were treated with melatonin (Sigma-Aldrich, St. Louis, MO) three times per week using both foliar spraying and application into the soil at the same concentration of 100 µM as previously reported ( Kabiri et al., 2018
James L. Gibson and Brian E. Whipker
Ornamental cabbage and kale (Brassica oleracea var. acephala) plants of cultivars Osaka White and Nagoya Red were treated with paclobutrazol and uniconazole as foliar sprays or substrate drenches. These treatments were compared to the industry standard of daminozide foliar sprays. Applying drenches of paclobutrazol (a.i.) at 4 mg/pot or uniconazole (a.i.) at 1 mg/pot (28,350 mg = 1.0 oz) resulted in 6% or 17%, respectively, shorter `Osaka White' plants while a 2 mg/pot paclobutrazol drench or a uniconazole drench at 0.25 mg/pot resulted in 25% shorter `Nagoya Red' plants. Although effective, the expense of substrate drenches for both plant growth regulators (PGRs) would not be economically feasible for growers to use. Paclobutrazol foliar sprays at concentrations of up to 80 mg·L-1 (ppm) were ineffective in controlling plant height and diameter of either `Osaka White' or `Nagoya Red'. A uniconazole foliar spray of 16 mg·L-1 resulted in 17% shorter `Nagoya Red' plants and 6% shorter `Osaka White' plants. A daminozide foliar spray of 2500 mg·L-1, sprayed twice, resulted in 21% shorter plants for both cultivars. Spraying daminozide would provide optimal height control for the retail grower. Although spraying daminozide twice controlled plant height and costs half the amount of an uniconazole spray at 16 mg·L-1, plant diameter was not affected with daminozide, therefore a wholesale grower who would desire a smaller diameter plant should use a uniconazole spray of 16 mg·L-1.
Tim D. Davis
Plugs of Zinnia elegans Jacq. `California Giant' and Tagetes erecta L. `Golden Climax' and `Grange Lady' were treated with foliar sprays of uniconazole solutions at 0, 5, 25, or 50 mg·liter-1 (spray volume = 120 ml·m-2). Ten days later individual plants were transplanted to OS-liter pots for evaluation of subsequent growth and flowering. All uniconazole treatments reduced height 10 days after application; the extent of reduction depended on uniconazole spray concentration. With zinnia, only the 50-mg·liter-1 foliar spray caused undesirable stunting for at least 1 month after transplanting. None of the uniconazole treatments affected time to anthesis for zinnia. With both marigold cultivars, all uniconazole treatments reduced growth the 2 weeks following transplanting. The highest concentration reduced marigold shoot growth during this period to 25% to 30% of untreated controls. Between 2 and 4 weeks after transplanting growth of all uniconazole-treated marigolds recovered to levels similar to the control. Time to anthesis was increased by the 50 mg·liter-1 treatment for both marigold cultivars. These results suggest that foliar sprays of uniconazole at 5 to 25 mg·liter-1 can control plug height during production without adversely affecting subsequent growth and flowering. with both zinnia and marigold, a single GA3 foliar spray of 100 mg·liter-1 at transplanting partially reversed the adverse post-production effects of the 50 mg·liter-1 uniconazole foliar spray.
Laura J. Lehman, C.R. Unrath, and Eric Young
Mature spur-type `Delicious'/seedling apple trees (Malus domestica Borkh.) were examined for 2 years after paclobutrazol (PB) foliar sprays with or without a soil cover to direct spray runoff away from the root zone, soil sprays, or a trunk drench. Foliar sprays with runoff reduced shoot number and fruit pedicel length in the year of treatment, but had no effect on shoot length. Trees that received foliar sprays with no runoff had fewer and shorter shoots and shorter pedicels the year after treatment. Soil sprays or a trunk drench reduced shoot number and pedicel length for 2 years after application, while only soil sprays reduced fruit weight, diameter, and length. Chemical name used: β- [(4-chlorophenyl)methyl]- α -(1,1-dimethylethyl)-1 H -1,2,4,-triazol-1-ethanol (paclobutrazol).
Laura J. Lehman, Eric Young, and C.R. Unrath
Spur-type or nonspur `Delicious' apple scions on either Malus domestica Borkh. (seedling) or M.26 rootstocks received paclobutrazol foliar sprays in one or two `consecutive years or a soil drench in the year of planting. For each scion, total shoot, root shank, and tree dry weights measured in the 3rd year after planting were suppressed by all treatments. Trees on M.26 put less dry weight into rootstock wood after foliar sprays, but trees on seedling were not similarly affected. No treatment influenced fibrous root dry weight of the spur-type scion on seedling, while all treatments suppressed dry-weight gain of the same scion on M.26. All trees had higher root: shoot ratios and blossom densities 3 years after the soil drench and several had higher ratios after foliar sprays. Chemical name used: ß-[(4-chlorophenyl)methyl] (l,l-dimethylethyl)-l-H-1,2,4-triazole-l-ethanol (paclobutrazol, PB).
S. Laywisadkul, C.F. Scagel, L.H. Fuchigami, and R.G. Linderman
decreases the amount of N mobilized from leaves to stems and roots in the autumn; thus, it can reduce N reserves required for growth the following spring ( Bi et al., 2003 ; Guak et al., 2001 ). The combination of foliar sprays with urea and CuEDTA can be
Qiang Liu and Yiwei Jiang
plants, and the remaining pots were allowed for recovery. Application of nitrogen and CK after de-submergence. The control and submerged plants were foliar-sprayed at 1, 2, 3, 7, and 14 d after de-submergence with the following treatments, respectively: 1
Margaret G. Aiken, Holly L. Scoggins, and Joyce G. Latimer
Ethephon [(2-chloroethyl) phosphonic acid] has been widely used as a foliar spray in the commercial greenhouse industry for decades to abort flowers, promote branching, and restrict plant growth ( Kays and Beaudry, 1987 ). Growers have reported