Experiments were conducted to evaluate the appropriate concentration of flurprimidol for ‘Orange Tiger’ tiger lily (Lilium lancifolium), the persistence of residual effects the following year with ‘Orange Tiger’, and differences in flurprimidol’s effect between tiger lily cultivars. In Expt. 1 flurprimidol was applied as a preplant bulb soak to determine its efficacy on height control of ‘Orange Tiger’ tiger lily. Bulbs were hydrated in 17 °C water for 1 h, allowed to drain 1 h, given 10 min soaks of 0, 5, 10, 20, 40, 80, and 160 mg·L−1 flurprimidol, and then allowed to drain for 1 h before potting. In Expt. 2 ‘Orange Tiger’ tiger lilies from Expt. 1 were then planted into outdoor beds to evaluate residual carryover effects of flurprimidol. Expt. 3 involved comparison trials of ‘Pink Tiger’, ‘White Tiger’, and ‘Yellow Tiger’ tiger lilies to determine if cultivars responded differently to flurprimidol drenches. Flurprimidol at 10 to 20 mg·L−1 effectively controlled stem elongation of ‘Orange Tiger’. No residual effect of flurprimidol on ‘Orange Tiger’ plant growth was observed a year after application. Optimal concentrations of flurprimidol for ‘Pink Tiger’ and ‘White Tiger’ were 2 to 5 mg·L−1 and for ‘Yellow Tiger’ 20 to 30 mg·L−1. Results showed that preplant bulb soaks prevented excessive height and provided plants that were more suitable in height for retail sales. Differential responses of ‘Pink Tiger’, ‘White Tiger’, and ‘Yellow Tiger’ tiger lilies to flurprimidol indicate that trials are required to customize optimal concentrations for other cultivars.
This study was conducted to compare different formulations of a slow-release fertilizer with a conventional fertilizer program to determine their impact on yield and growth of bell pepper (Capsicum annuum). Two formulations of a methylene-urea slow-release fertilizer (Nitamin®) were evaluated on drip-fertigated and plastic-mulched bell peppers during 2006 in the eastern coastal plain and western Appalachian mountains of North Carolina. Liquid slow-release formulations were applied the first 6 or 9 weeks of the growing season and a dry formulation was banded at planting. Treatments were compared with the extension-recommended rate of 200 lb/acre nitrogen (N) (NC-200) and a high-input fertilizer rate of 300 lb/acre N (HI-300) from calcium nitrate injected in 12 weekly applications of drip irrigation. Irrigation was applied twice per week. The slow-release granular formulation at 200 lb/acre N produced the highest marketable yield and better canopy quality in eastern soil. Early marketable yield for this treatment accounted for 46% of the total yield. All slow-release treatments had higher N use efficiency (NUE) values than NC-200 and HI-300 in the eastern study. In loam soil (western study), pepper yield was statistically similar among treatments. Lower rates (150 lb/acre N) of slow-release fertilizer performed as well as NC-200 and HI-300 for marketable yield. Low rates (150 lb/acre N) of one of the liquid formulations performed better in total and marketable NUE than NC-200 and HI-300 in Fletcher, North Carolina. Liquid and dry formulations of slow-release fertilizer showed a potential to be used on bell pepper production across the state at reduced N rates, with greater impact on yield in coarse-textured soils found predominantly in the eastern coastal plain region.
Sages (Salvia sp.) have long been popular as summer annuals, culinary herbs, and landscape perennials. We selected ‘Hot Lips’ hybrid sage [Salvia ×microphylla (Salvia greggii × S. microphylla)], a recently introduced perennial sage, to assess efficacy of the growth regulator flurprimidol for controlling height. Substrate drenches of flurprimidol at 0, 0.25, 0.50, 1.0, 2, and 4 mg per pot were applied using 240 mL of solution per pot on 17 June 2010. Plant height was recorded at treatment, 27 days after treatment (DAT), and 48 DAT. Flurprimidol drench concentrations of 0.25 mg per pot and higher controlled plant height by 20% to 41% 27 DAT and by 26% to 50% 48 DAT. While all treatments at 48 DAT produced a significantly shorter plant, concentrations between 0.25 to 1 mg would provide growers options for controlling plant growth by 26% to 44%. Using concentrations over 1.0 mg did not produce any additional control of height in hybrid sage.