Efficient N fertilizer management is crucial for ensuring maximum economic production and improving N recovery efficiency ( Guan et al., 2011 ; Zhang et al., 2013 ). To increase root yield of the radish, excessive N fertilizers are applied in the
A series of experiments were conducted to determine the sensitivity of radish to four light alcohols (ethanol, methanol, 2-propanol, and t-butanol) identified as atmospheric contaminants on manned spacecraft. Radish (Raphanus sativus L. `Cherry Bomb' Hybrid II) seedlings were exposed for 5 days to concentrations of 0, 50, 100, 175, 250, and 500 ppm of each alcohol and the effect on seedling growth was used to establish preliminary threshold response values. Results show a general response-pattern for the four alcohol exposures at threshold responses of 10% (T10), 50% (T50) and 90% (T90) reduction in seedling length. There were differences in the response of seedlings to the four alcohols, with the T10 for t-butanol and ethanol (25 to 40 ppm) being 3 to 5× lower than for methanol or 2-propanol (110 to 120 ppm). Ethanol and t-butanol exhibited similar T50 values (150 to 160 ppm). In contrast, T50 for methanol (285 ppm) and 2-propanol (260 ppm) were about 100 ppm higher than for ethanol or t-butanol. Chronic exposures to 400 ppm t-butanol, ethanol or 2-propanol were highly toxic to the plants. Radish was more tolerant of methanol, with T90 of 465 ppm. Seeds did not germinate at the 500 ppm treatment of t-butanol, 2-propanol, or ethanol. There were significant differences in projected performance of plants in different environments, dependent upon the regulatory guidelines used. The use of exposure guidelines for humans is not applicable to plant systems.
Intact roots of 109 radish (Raphanus sativus L.) cultivars were analyzed for glucosinolates (GS’s) and found to contain primarily 4-methylthio-3-butenyl-GS with small amounts of 4-methylsulfinylbutyl-, 4-methylsulfinyl-3-butenyl-, and 3-indolylmethyl-GS’s. Cultivars included oil radishes (ssp. oleifera) and food radishes (ssp. radicola) available in European, European-American, Japanese, and Korean markets. Regarding total GS’s, 80% or more of the red European-American radishes had 100-199 pmole/100 g, the Korean 100-299, and the Japanese 200-399. No correlation was found between root size and 4-methylthio-3-butenyl-, 3-indolylmethyl-, or total GS’s. Japanese radish peelings contained significantly greater concentrations of these 3 constituents than did the peeled root.
1 To whom reprint requests should be addressed. E-mail address: Thomas.Luebberstedt@agrsci.dk The authors thank Andrea Schieder (radish breeder at the breeding company Juliwa-Enza) and the breeding company Nunhems for their generous cooperation in
Radish, a member of the Brassicaceae family is an important cool-season crop grown in rotation with sugarcane ( Saccharum spp. hybrids), leafy vegetables, and rice ( Oryza sativa L.) in the EAA of south Florida. The EAA is dominated by organic
Japanese radish sprouts are popular in Japanese food. They are easy to grow and nourishing, and they are often grown at home in Japan. Commercially, 2767 t of Japanese radish sprouts is grown each year ( Statistics Bureau of Japan, 2014 ) in plant
head, experienced no leaf damage or decrease in growth ( Fett, 2002 ). In contrast, H 2 O 2 phytotoxic effects were reported at concentrations as low as 9 and 12 mg·L −1 , when applied every 6 h, resulting in the yellowing of radish and garden cress
Callus initiation and growth and plantlet regeneration were studied using eight cultivars of Raphanus sativus L., including six Japanese radishes, one Chinese and one small `Comet' radish. The basal medium was composed of Murashige and Skoog inorganic salts, 2.0 mg myo-inositol/liter, 0.5 mg each of nicotinic acid and pyridoxine·HCl/liter, and 0.1 mg thiamine·HCl/liter, 30 g sucrose and 2 g Gelrite/liter. High callus yields were obtained on basal medium containing (mg·liter-1) 0.1 2,4-D and 1.0 BA for two Japanese radishes and 0.1 NAA and 1.0 kinetin for `Comet' radish. Shoots were regenerated from callus by subculturing on basal medium containing 0.1 or 1.0 mg BA/liter and then transferring to basal medium. Rooting occurred on basal medium. Although callus was obtained in all eight cultivars, shoots and plantlets were regenerated only from `Moriguchi', `Nerima Shirinaga', and `Comet'. Chemical names used: 2-(l-naphthyl) acetic acid (NAA); N-(phenylmethyl)-lH-purine-6-amine (BA); 2,4-dichlorophenoxy acetic acid (2,4-D); 6-(furfurylamino)purine (kinetin).
Growth of both plant tops and roots of radish (Raphanus sativa L. cv. Cherry Belle) was increased under elevated CO2 conditions in plastic, environmentally-controlled growth chambers. The root-shoot ratio was also favorably influenced by CO2 enrichment of the plant environment.
Greenhouse grown radishes (Raphanus sativus L. cultivar Cherrybelle) were sprayed at the first true leaf stage 7 days after sowing with 2000, 4000 and 8000 ppm succinic acid-2,2-dimethylhydrazide (SADH). Root fresh weight, root/leaf ratio, and photosynthesis rate were increased in treated plants. Reducing sugar content was decreased in 2 of 3 experiments. Leaf weight and % dry matter of roots were not significantly changed by SADH treatments.