terrestrial weed control, and then evaluated the efficacy and selectivity of acetic acid, d-limonene, and combinations of the two on waterhyacinth, waterlettuce, pickerelweed ( Pontederia cordata ), and broadleaf sagittaria ( Sagittaria latifolia ). They
citrus oil are less common. Avenger Weed Killer Concentrate (Cutting Edge Formulations, Buford, GA) contains 70% d-limonene. The label indicates the product should be diluted at 1:6 (10% d-limonene for small annual weeds) to 1:3 (17.5% d-limonene) for
gardens and organic farming. Gettys et al. (2021 ) reviewed the literature regarding the use of these types of products for terrestrial weed control and evaluated the effects and selectivity of acetic acid, d-limonene, and combinations of the two on
tested in triplicate. Statistical methods. The effect of DT on essential oil content and the concentration and yield of alpha-pinene, beta-pinene, myrcene, delta-3-carene, limonene, cis-ocimene, linalyl anthranilate, alpha-terpinyl acetate, germacrene
Abstract
The growth-retardant effects of succinic acid-2,2-dimethylhydrazide (SADH), 1 n-alkyl and 2 benzyl quaternary ammonium derivatives of (+)-limonene were determined after application of 2 foliar sprays on young grapefruit (Citrus paradisi Macf.) seedlings which were subsequently pruned to remove all growth. Only the n-alkyl derivative, l-p-menthanol-2-dimethylamino heptyl bromide (Q-58), caused dwarfing and marked internode shortening of new growth on all treated plants 71 days after the second foliar spray. A similar experiment on a larger scale using Q-58 and 2 new n-alkyl derivatives of (+)-limonene produced retardation of new growth for 136 days after the second foliar spray. However, true dwarfing was only apparent in a few of the treated seedlings. These results indicate that n-alkyl quaternary ammonium derivatives of (+)-limonene are stored in the roots or lower stems of grapefruit seedlings and can continue to retard terminal shoot development for about 4 months after treatment.
Abstract
The growth-retardant activity of 4 quaternary ammonium derivatives of (+)-limonene was determined by application of foliar sprays on greenhouse-grown grapefruit seedlings. The most active compound was 1-p-men-thanol-2-dimethylamino heptyl bromide. The 3,4-dichlorobenzyl chloride and p-methylbenzyl chloride quaternary ammonium derivatives of 2-dimethylamino-1-p-menthanol were occasionally rated as highly active, but in some tests these compounds were either only slightly active as growth retardants or moderately active as growth stimulators. The 2,4-dichlorobenzyl chloride derivative was only moderately active on grapefruit seedlings. Alar in some tests was moderately effective as a growth retardant, and in other tests it was either inactive or somewhat active as a growth stimulator. The heptyl derivative at 3000 and 6000 ppm was also effective in reducing growth of 3-year-old field-grown lemon trees for a relatively short period of time. A 1000 ppm application appeared to stimulate growth of lemon trees and grapefruit seedlings.
Consolidated, Springfield, IL) at 10% by vol. spray solution (2011 and 2012), d -limonene (GreenMatch Burndown Herbicide ® , 55% d -limonene; Marrone Bio Innovations, Davis, CA) at 14% spray solution (2013 only). The citrus by-product d -limonene was
, 2012 ). Each of these tools has specific limitations in vineyards and other cropping systems. For example, Shrestha et al. (2012) reported that steam, propane flaming, and an organic herbicide (d-limonene) provided 3 to 6 weeks of weed suppression in
/flavor compounds in mandarin oranges, as previously published ( Tietel et al., 2011 ). For example, herein are included all eight consensus compounds (α-pinene, β-myrcene, limonene, linalool, nonanal, 4-terpineol, α-terpineol, and decanal) previously recovered in
Center for Natural Products Research in Oxford, MS, using the GC methods described in Zheljazkov et al. (2010a) . Quantitative analysis. Commercial standards (–)-carvone and ( R )-(+)-limonene were obtained from Fluka (Buchs, Switzerland). With five