Vase Life of Imported Anthurium Flowers Evaluated in Japan In

HORTSCIENCE 40(5):1439–1443. 2005. physiological conditions of cut anthuriums during shipment or in different seasons. The study also presents preliminary evidence sug- Vase Life of Imported Anthurium gesting that bacterial growth was related to the Flowers Evaluated in Japan vase life of bunched anthuriums. in Relation to the Effects of Materials and Methods Anthurium fl owers. Cut anthurium fl owers of ‘Tropic Fire’ (red, tulip-type spathe) and Postimportation Benzyladenine ‘Red Leilani’ (red, heart-shaped spathe), with spathe in about 10 cm-diameter and 40-cm- Treatment long scape attached, were directly imported from Green Point Nurseries in Hilo, Hawaii by Ryo Fukui, Saori Kikuchi, Yuko Ichida, and Hitoshi Honjo air-freight. The fl owers were not treated with Department of Bio-productive Science, Utsunomiya University, 350 Mine, any chemicals at the nursery before shipping, Utsunomiya, Tochigi 321-8505, Japan and delivered to the laboratory in a double- layered cardboard box with moistened paper Additional index words. bacterial blight, calcium chloride, climatological infl uences, fl ower sheets fi lled inside the inner box to maintain senescence, international marketing, tropical agriculture humidity during shipment. The fl owers were Abstract. Effects of postimportation treatment of benzyladenine (BA) on vase life of imported used for the tests within 5 to 7 d after being anthurium fl owers was examined after receiving the fl owers in Japan and placing them either shipped out of the nursery, and stored above individually or together in vase solution. Cut anthuriums of two cultivars imported from Hawaii 15 °C in the laboratory until use. via air-freight were sprayed with 200 µg·mL–1 of BA upon arrival, and vase life of the fl owers Room condition. An enclosed room parti- were evaluated by numerating days before observing apparent discoloration at the distal end tion (150 × 120 cm, 90 cm in height) was of spadix. BA treatment signifi cantly extended the vase life (by up to 22 d) in two cultivars constructed in the laboratory to provide a in most cases during summer, but the effect was inconsistent in each cultivar when the test constant illumination and minimize fl uctuation was done in winter. The effect of BA verifi ed in summer was either nullifi ed or signifi cantly of temperature during evaluation of vase life of diminished by placing 10 fl owers together in vase solution. In these tests, bacteria were isolated the fl owers. The top and four sides of the room more frequently from the scape segments of bunched fl owers than those of individual fl owers. partition were enclosed with Styrofoam boards However, vase life was not affected when the vase solutions were inoculated with Xanthomonas (9 or 18 mm thick), and each inner surface of axonopodis pv. dieffenbachiae. These results indicate that the postimportation BA treatment is which were pasted with a high light-refl ect- mostly effective in extending the vase life of cut anthuriums during summer, but may not be ing white polyethylene fi lm (Tyvek, DuPont, reliable during winter in temperate regions. The preliminary evidence suggests that bacterial Maruwa Biochemicals Corp., Tokyo, Japan) to growth in vase solution be related to the loss of the effect of BA, but the pathogen of bacterial equalize the light condition inside the partition. blight growing in the vase solution or invading the xylem of the scape is not responsible for Two 20-W fl uorescent lamps were installed at the reduced longevity of imported anthuriums. the top of the room partition, and the area was illuminated for 14 h every day. When lighted Anthurium is the major ornamental product or spray was effective in delaying senescence up, the light intensity measured with a quantum in Hawaii. For its long-lasting fl owers, the of cut fl owers and increased the vase life by sensor was 8.1 to 10.0 µmol·m–2·s–1 PPFD at main focus of the local anthurium industry 1.4 to 3.2 fold (up to 51 d) in most cultivars. the center of the partition unit and 6.7 to 10.0 was to expand the market for the cut fl owers However, as for cut anthuriums shipped to the µmol·m–2·s–1 PPFD at the corners. In each sea- in the mainland (Shehata, 1995) and Japan temperate regions, the effect of BA needs to be son, moderate cooling or heating was applied (Kogure, 1994). To ensure the best quality of examined also at winter indoor temperatures in the laboratory room in order to simulate the products in this scheme, the fl owers need and by using the fl owers actually sent by air- average indoor environment in summer or to endure tough conditions during air-freight freight to verify the results with those treated winter. Temperature and relative humidity (RH) and still have long vase life when displayed at at the place where they are harvested. In an inside the room partition were monitored hourly the local retailer. Thus, treatments for extend- earlier study, cut anthuriums briefl y dipped in using an automated thermo-recorder (RS-11, ing the longevity of cut anthuriums are needed a BA solution after 30-h shipping from Hawaii Espec Mic Corp., Aichi, Japan). to maintain and improve their qualities after to Michigan showed only a marginal increase Summer tests. The fi rst experiment was receiving the fl owers from Hawaii. in vase life (Shirakawa et al., 1964), suggesting done in Summer 2001. Soon after removing Various methods of delaying senescence that postshipping BA treatment be ineffective the fl owers from the shipping box, the proximal of cut fl owers have been reported for a vari- or the effect of BA could be affected by the ends of the scapes were cut off in water to leave ety of plants, e.g., application of exogenous conditions involved in shipping. 30-cm portions of the scapes. Flowers showing cytokinin (Nooden and Leopold, 1988; Van The objectives of this study were to examine any damages on their spathe and spadix were

Staden et al., 1990) or CaCl2 (Gerasopoulos the responses of imported cut anthuriums to discarded. Then, a set of 10 fl owers each of and Chebli, 1999), treating cut fl owers with postimportation BA treatment during summer ‘Tropic Fire’ and ‘Red Leilani’ was sprayed ethylene inhibitors such as animothoxyvinyl- and winter in Japan to evaluate seasonal and with a solution of N6-benzyladenine (Kanto glucine and aminooxyacetic acid (Salisbury climatological infl uences on the effect of BA Kagaku, Tokyo, Japan) prepared with distilled and Ross, 1992), or addition of sucrose in vase on the vase life. Vase life was evaluated for water at 200 µg·mL–1 until water droplets run off water (Huang and Chen, 2002; Ichimura and individual fl owers as well as those placed to- from the spathe and spadix. Nontreated fl owers Hisamatsu, 1999). For anthuriums, a study done gether in a vase, since the fl owers are usually were sprayed with distilled water. Another set in Hawaii (Paul and Chantrachit, 2001) has placed together in vase water when displayed of 10 fl owers each of two cultivars was soaked

shown that benzyladenine (BA) applied as a dip at the retailer. The responses of the fl owers in a 1.0% solution of CaCl2 prepared with tap to treatment with CaCl2 were also examined water for 1 h, and the fl owers for the control We thank the Gene Bank of Ministry of Agriculture, in order to verify the precision of the results to this treatment were soaked in tap water. Fisheries, and Forestry for providing us with the strains over time. Since CaCl2 is expected to affect cut After water droplets retained on the scape were of X. campestris pv. dieffenbachiae and the National anthuriums differently from BA as judged by wiped off, all fl owers were placed individually Institute of Agrobiological Sciences for assisting us its effects on cut gerberas (Gerasopoulos and in test tubes (17.5 × 1.2 cm) fi lled with 20 mL in using the Biolog MacroStation System. Chebli, 1999), it was used as the additional of vase solution containing 1.0% sucrose, 50 1E-mail [email protected]. control to identify unexpected changes in µg·mL–1 silver nitrate, 50 µg·mL–1 citric acid,

HORTSCIENCE VOL. 40(5) AUGUST 2005 1439

AAugustBook.indbugustBook.indb 11439439 66/14/05/14/05 112:23:142:23:14 PPMM and 4 µg·mL–1 sodium hypochlorite. Then the fl owers, additional sets of BA-treated and non- cells of each strain were suspended in distilled openings of the tubes were sealed with para- treated fl owers placed individually in the tubes water. Cell density in each cell suspension fi lm to avoid excessive loss of vase solution were prepared without sealing the openings of (turbidity) was adjusted to about 109 colony by evaporation, and the tubes were installed the tubes to equalize the conditions between forming units/mL using McFarland nephelom- in test tube racks randomly placed inside the individual fl owers and those put together in eter (Lennette, 1985). The cell suspensions of room partition. Meantime, a separate set of 10 the vase solution. Both experiments were three strains were mixed in equal volumes, and fl owers each of two cultivars was treated with done with 10 replications for each treatment 20 µL each of the mixture was inoculated to 20 BA as described above, but these 10 fl owers and cultivar. mL of vase solution or the same vase solution were placed together in 300-mL erlenmeyer The experiment to determine the extent of prepared without adding sucrose in test tubes. fl ask fi lled with 200 mL of the same vase solu- bacterial colonization inside the scapes also Inoculation of bacteria to vase solution was also tion. Additional sets of 10 nontreated fl owers was repeated in Summer 2002 using cut fl owers made with three strains isolated from the vase were prepared similarly and placed together of ‘Tropic Fire’. Additional sets of BA-treated solutions (strains UXC99 and UXC113) or the in the fl ask. The openings of the fl asks for and nontreated fl owers placed individually in scape segment (UXC143E) of different fl owers these fl owers were not sealed. In all cases, the tubes or together in the fl ask were prepared in the previous experiment. The colonies of vase solution was fi lled up approximately to separately, since the fl owers were to be sec- these three strains grown on TZC (Norman and the initial level when the remaining volume tioned before the end of the vase life to examine Alvarez, 1989) and YDC (Wilson et al., 1967) of the solution decreased to about one fourth the extent of bacterial colonization inside the media were typical of those of Xanthomonas of the original volume. Every 2 to 3 d, the scapes during the earlier stages. Bacteria grow- spp. These three stains of bacteria were in- fl owers were observed visually for any visible ing inside the scapes were detected 4 and 6 oculated to the vase solutions as described discoloration in the spadix, and all fl owers weeks after treatment as described previously. above, and the control tubes (nontreated) were were repositioned randomly inside the room The experiment was done with 10 replications not inoculated with any bacterial strains. The partition. Vase life of the fl owers was evaluated for each treatment in each time. fl owers of ‘Tropic Fire’ were prepared by

by numerating days before >10% portions of Winter tests. The effects of BA and CaCl2 cutting off their scapes to leave the 30-cm the spadix were discolored in black or dark on vase life of the fl owers were examined portions as described previously and wiping brown at its distal end. twice, once in Winter 2001–02 and once in the scapes with 70% ethanol. The fl owers then At the end of the experiment (51 d after Winter 2003, using the same two cultivars by were placed individually in the tubes, and the treatment), bacteria were recovered from the the method described previously. The open- openings of which were sealed with parafi lm. fl owers to determine the extent of bacterial ings of the tubes were sealed with parafi lm The experiment was done in Summer 2002 colonization inside the scapes. All fl ow- in these two experiments, each of which was with 10 replications for each treatment and ers were removed from the vase solution, done with 10 replications for each treatment vase solution, and vase life of the fl owers was surface sterilized by soaking their scapes in and cultivar. evaluated as described above. 5% commercial bleach and wiping off with Inoculation of bacterial strains into the Identifi cation of unidentifi ed bacterial 70% ethanol, and the individual scapes were vase solution. A test was made to determine strains. The three unidentifi ed bacterial strains sectioned into 1-cm segments from the distal if Xanthomonas campestris pv. dieffenbachiae used in the inoculation test were identifi ed to to proximal end using a disinfested blade on a (McCulloch and Pirone 1939) Dye (X. axo- the genus level by the standard bacteriological disinfested cutting board. The sectioned scape nopodis pv. dieffenbachiae [Vauterin et al., tests (Schaad et al., 2001). The identities of segments then were sequentially stamped 1995]), the causal agent of bacterial blight of the strains were further examined by Biolog (proximal end down) on the surface of a plate anthuriums, growing and spreading in the vase MicroStation system (Biolog Inc., Hayward, of BGT medium (Saile et al., 1997). The plates solution and subsequently invading the xylem CA) with the database of MicroLog3 (release were incubated for 3 to 5 d at 28 °C to detect of the scape was responsible for shortening 3.50) using the standard BUGM medium colonies of bacteria growing at the respective the vase life of the fl owers. Three strains of X. containing 5% sheep blood. positions on each plate. campestris pv. dieffenbachiae, MAFF301636 Statistical analysis. All experiments were The experiment was repeated in Summer to 301638, were obtained from Gene Bank of conducted in complete randomized design. 2002. In the second series of summer experi- Ministry of Agriculture, Fisheries and Forestry Data were analyzed by two-way analysis of

ments, the effects of BA and CaCl2 on vase in Japan. These strains were grown individually variance (ANOVA) to examine the effects life of the fl owers were examined as described on agar plates of peptone-dextrose medium of the main treatment and subtreatment previously using the same two cultivars. For (1.0% peptone, 0.5% glucose, and 1.7% agar (cultivar, time, or type of vase solution), and the test to examine the effect of bunching the in distilled water) for 2 d at 28 °C, and the their interactions. Means were separated by

Table 1. Weekly mean temperature and relative humidity (RH) during two summer and two winter experiments.z Summer 2001y Summer 2002x Winter 2001–02w Winter 2003v Week Temp (°C) RH (%) Temp (°C) RH (%) Temp (°C) RH (%) Temp (°C) RH (%) 1 27.2 ± 1.3 52.4 ±13.1 27.5 ± 1.1 52.2 ±10.7 17.8 ± 2.3 36.8 ± 5.2 17.9 ± 1.8 26.5 ± 4.4 2 27.3 ± 1.1 53.0 ± 9.3 27.7 ± 1.1 48.0 ± 6.6 18.4 ± 2.5 30.3 ± 7.8 16.2 ± 1.6 24.5 ± 5.7 3 26.6 ± 1.4 52.3 ± 9.0 28.6 ± 0.8 54.3 ± 8.3 16.0 ± 2.3 30.3 ± 4.6 16.6 ± 1.6 22.9 ± 2.9 4 26.3 ± 1.1 66.8 ± 9.6 28.9 ± 1.1 50.3 ±10.1 15.0 ± 2.1 32.0 ± 3.3 18.4 ± 1.6 27.9 ± 7.2 5 26.9 ± 1.1 55.7 ± 9.3 27.8 ± 0.9 51.5 ±10.5 13.2 ± 2.2 34.5 ± 4.5 17.7 ± 1.5 25.3 ± 4.4 6 26.9 ± 1.7 61.8 ±10.6 27.3 ± 0.9 54.0 ± 9.2 16.1 ± 2.0 36.7 ± 7.0 17.7 ± 1.6 27.8 ± 5.0 7 26.5 ± 0.8 57.2 ± 8.5 28.1 ± 1.0 46.3 ± 7.1 ------17.9 ± 1.4 24.3 ± 5.7 8 25.9 ± 0.8 58.3 ± 4.8 27.0 ± 0.8 54.8 ± 9.9 ------17.6 ± 1.6 23.7 ± 6.0 9 ---u --- 25.9 ± 0.9 55.5 ± 7.5 ------18.0 ± 1.5 27.5 ± 5.7 10 ------25.8 ± 1.3 48.6 ± 7.6 ------20.4 ± 2.6 39.6 ± 7.9 11 ------24.9 ± 1.5 60.7 ±10.0 ------12 ------25.2 ± 1.0 53.6 ± 7.1 ------Ave. 26.7 57.2 27.1 52.5 16.1 33.4 17.8 27.0 zRoom temperature and relative humidity were recorded hourly, and the weekly mean values were calculated with the hourly data. The mean value is expressed with a range of one standard deviation. yWeek 1 started on 17 July 2001. xWeek 1 started on 18 July 2002. wWeek 1 started on 6 Dec. 2001. vWeek 1 started on 17 Jan. 2003. uData were not recorded after the experiment was completed.

1440 HORTSCIENCE VOL. 40(5) AUGUST 2005

AAugustBook.indbugustBook.indb 11440440 66/14/05/14/05 112:23:172:23:17 PPMM protected Fisher’s least signifi cant difference had no signifi cant effects on the vase life in of scape segments from which bacteria were (LSD) test. both cultivars. isolated was signifi cantly greater in the fl ow- Extent of bacterial invasion into the scape. ers placed together in vase solution than the Results In the test done in Summer 2001, the number individual fl owers regardless of BA treatment

Temperature and RH during the tests. The Table 2. Effects of BA and CaCl2 treatments and bunching the fl owers on vase life of cut anthuriums in data recorded during the two summer and the fi rst summer test.z two winter tests revealed that temperature Vase life (d)y was maintained fairly constantly during each Treatment Tropic Fire Red Leilani Avg test period (Table 1). In average, the weekly Nontreated/individual fl owers 40.0 37.2 38.6 ab mean temperatures during two summer periods Nontreated/in a bunch 32.0 38.3 35.2 a were about 10 °C higher than those during two Sprayed with BA/individual 51.5 51.1 51.3 c winter periods, and the weekly mean values Sprayed with BA/in a bunch 39.6 44.7 42.2 b for RH during two summers were about 20% Soaked in water 39.6 43.8 41.7 b

to 30% higher than the values during two Soaked in CaCl2 solution 38.9 38.6 38.8 ab winter periods. zStarted in week 1, 2001. yThe values were means of 10 replications. Based on two-way (treatment by cultivar) ANOVA, the main Effects of BA and CaCl2 treatments in summer. BA treated to individual fl owers treatment effect was signifi cant (P < 0.01), but the effects of cultivar and the treatment by cultivar interac- signifi cantly extended the vase life of the fl ow- tion were not signifi cant. The values for the average indicated with the same letters are not signifi cantly ers of two anthurium cultivars in most cases different according to Fisher’s protected LSD test (P = 0.05). except for ‘Red Leilani’ in the second summer. Table 3. Effects of BA and CaCl treatments and bunching the fl owers on vase life of cut anthuriums in For ‘Tropic Fire’, BA treatment signifi cantly 2 the second summer test.z extended the vase life consistently in two sum- mer periods regardless of sealing of the test Vase life (d)y tubes: the vase life was extended by 11.5 d in Treatment Tropic Fire Red Leilani Avg Summer 2001 (Table 2) and by 14.7 or 22.2 Nontreated 32.8 ay 37.3 ab --- d in Summer 2002 (Table 3). The vase life of Sprayed with BA 55.0 c 43.0 b --- ‘Red Leilani’ also was extended by 13.9 d in Soaked in water 37.6 ab 41.2 ab --- Soaked in CaCl solution 37.3 ab 38.5 ab --- Summer 2001 (Table 2) and 16.8 d in the test 2 Nontreated examining the effect of bunching fl owers in Individual fl owers 30.4 33.1 31.8 Ax Summer 2002 (Table 3). The vase life of ‘Red 10 fl owers in a bunch 28.0 29.8 28.9 A Leilani’ also increased from 37.3 to 43.0 d in Sprayed with BA the other test done in Summer 2002, but the Individual fl owers 45.1 49.9 47.5 C difference was not signifi cant. 10 fl owers in a bunch 40.9 40.0 40.5 B This effect of BA on cut anthuriums, how- zStarted in week 1, 2002. ever, was nullifi ed or diminished by placing 10 yThe values were means of 10 replications. Based on two-way (treatment by cultivar) ANOVA, the main fl owers together in the vase solution. In the fi rst treatment effect and the treatment by cultivar interaction were signifi cant (P < 0.05). The means indicated test, bunching treatment on BA-treated fl owers with the same letters are not signifi cantly different according to Fisher’s protected LSD test (P = 0.05). reduced the average vase life in two cultivars xBased on two-way (treatment by cultivar) ANOVA, the main treatment effect was signifi cant (P < 0.01) to 42.2 d, the value that was not signifi cantly but the effect by cultivar and the treatment by cultivar interaction were not signifi cant. The means of the average indicated with the same letters are not signifi cantly different according to Fisher’s protected LSD different from that for nontreated individual test (P = 0.05). fl owers (Table 2). In the second test in Sum- mer 2002, the average vase life of BA-treated Table 4. Effects of BA and CaCl treatments on vase life of cut anthuriums in two winter tests.z fl owers in two cultivars were also reduced from 2 47.5 to 40.5 d by bunching the fl owers (Table Vase life (d)y 3). Bunching treatment on nontreated fl owers Winter 2001–02 Winter 2003 did not have any effects on the vase life in both Treatment Tropic Fire Red Leilani Tropic Fire Red Leilani cultivars in both tests. No signifi cant effects Nontreated 38.4 ab 42.1 bcd 66.0 c 25.3 a by soaking in water or CaCl2 solution were Sprayed with BA 46.3 d 43.7 cd 67.4 c 55.0 b observed in any cases (Tables 2 and 3). Soaked in water 35.7 a 41.2 bc 51.8 b 28.3 a Soaked in CaCl solution 36.0 a 40.0 abc 48.1 b 27.1 a Effects of BA and CaCl2 treatments in 2 winter. Unlike the results obtained during two zStarted in week 1 in the respective years. summer periods, the effect of BA treatment yThe values were means of 10 replications. The effects of treatment and cultivar and their interaction were during winter on extension of the vase life was all signifi cant (P < 0.01) for the fi rst experiment, and the effects of treatment and cultivar were signifi cant (P rather inconsistent in each year and cultivar < 0.05) with no signifi cant interaction for the second experiment. The means for each experiment indicated (Table 4). In the fi rst winter test, the signifi cant with the same letters are not signifi cantly different according to Fisher’s protected LSD test (P = 0.05). effect of BA treatment was evident only in ‘Tropic Fire’, extending its vase life by 7.9 d as Table 5. The extent of invasion by saprophytic bacteria into the scape of cut anthuriums of two cultivars compared with that for the nontreated fl owers when sprayed with BA and/or placed together in a base.z (38.4 d). The vase life of ‘Red Leilani’ fl owers No. of scape segments ranged from 40.0 to 43.7 d for all treatments colonized by saprophytic bacteriay in this test. In contrast, the signifi cant effect Treatment Tropic Fire Red Leilani of BA treatment was only evident in ‘Red Nontreated/individual 04.9 a 13.2 b Leilani’ in the second winter test, extending Nontreated/in a bunch 19.3 c 29.8 d its vase life by 29.7 d as compared with that Sprayed with BA/individual 02.3 a 13.8 bc for the nontreated fl owers (25.3 d). In this Sprayed with BA/in a bunch 17.7 bc 40.0 e test, the vase life of BA-treated or nontreated zStarted in week 1, Summer 2001. Isolation of bacteria from the scape segments was made at the end of fl owers of ‘Tropic Fire’ was as long as 66.0 summer experiment (after 51 d of incubation) in 2001. y or 67.4 d, and was longer by >15 d than that The values were means of 10 replications. Based on two-way (treatment by cultivar) ANOVA, the effects for the fl owers soaked in water or CaCl solu- of treatment and cultivar and their interaction were all signifi cant (P < 0.01). The means indicated with the 2 same letters are not signifi cantly different according to Fisher’s protected LSD test (P = 0.05). tion. In both tests, soaking in CaCl2 solution

HORTSCIENCE VOL. 40(5) AUGUST 2005 1441

AAugustBook.indbugustBook.indb 11441441 66/14/05/14/05 112:23:202:23:20 PPMM (Table 5). This signifi cant trend was evident the spadix, since signs of senescence usually 27%. However, even this is within the seasonal in both cultivars, but the overall frequency of appear fi rst on the spadix and also it was dif- fl uctuation of vase life (8 to 69 d) routinely recovering bacteria from scape segments was fi cult to make visible evaluations on spathe observed in the past (Paul et al., 1992). These consistently greater for ‘Red Leilani’ than blueing and the gloss of spathe consistently results suggest that the fl uctuations by season ‘Tropic Fire’. The same tendency was observed over a series of experiments done in different of harvest and cultivar are probably responsible in the second summer test when the extent of seasons. Nonetheless, our evaluation scheme for the inconsistent effects of BA observed bacterial invasion into the scape of ‘Tropic Fire’ on the spadix was comparable to the scheme during winter.

fl owers was reexamined during the early stage used previously by Paul and Chantrachit Treatment with CaCl2 did not affect the of vase life. The number of scape segments (2001): fl owers were discarded when they vase life in any cases. Calcium suppresses containing bacteria was greater in the bunched were rated 4 of the spadix senescence index ethylene production when accumulated in fl owers than the individual fl owers regardless from 1 (no senescence) to 5 (>50% of spadix plant tissues, and it was reported the vase of BA treatment at both times of sectioning showing senescence). In this study, BA treat- life of cut gerberas extended by 3.3 to 5.9

(Table 6); but the differences were signifi cant ment in summer extended the vase life by 11.5 d by injecting 1% CaCl2 and up to 4.8 d by only for nontreated fl owers. to 22.2 d, or 1.3- to 1.7-fold, in two cultivars. soaking into the solution (Gerasopoulous and Identification of bacterial strains by This is comparable to 1.4- to 2.5-fold increase Chebli, 1999). Apparently, such effects of

Biolog system. Stains UXC99, UXC113, and of vase life (by 13 to 24 d) in most cultivars CaCl2 were not evident in anthuriums in both UXC143E were identifi ed as X. campestris pv. previously recorded in Hawaii for the fl owers summer and winter, suggesting senescence poinsetticola (probability = 98%), X. campes- held at 22 °C and 70% to 80% RH (Paul and of fl owers is regulated by other mechanisms tris pv. poinsetticola (probability = 99%), and Chantrachit, 2001). These results indicate that in anthuriums. It is noteworthy, however, that X. campestris pv. malvacearum (probability = BA is effective in delaying senescence in the the vase life of ‘Tropic Fire’ fl owers soaked in

100%), respectively. responsive cultivars whether it is applied before CaCl2 solution or tap water in the second winter Effects of bacteria inoculated to the vase shipping or after unpacking the fl owers. test was signifi cantly shorter than nontreated solutions on the vase life. Vase life of ‘Tropic This effect of BA, however, was inconsis- fl owers. The reason for which is not known; Fire’ fl owers was not affected either by ad- tent for each cultivar in each year when the but soaking in cold water during winter may dition of sucrose in the vase solution or by same treatment was made during winter. The have caused undefi ned physiological changes inoculations of both mixtures of bacteria into previous study showed that the effect of BA on in fl owers of this cultivar. the vase solution (Table 7). extention of vase life depended upon season The effect of BA on extension of vase of harvest and cultivar (Paul and Chantrachit, life observed during summer was nullifi ed Discussion 2001). Thus, the two studies done in different or signifi cantly reduced by placing the fl ow- climatic zones point to the same conclusion. ers together in the same vase solution, and BA sprayed to individual cut anthuriums Even without treatment with BA, the vase life bacteria were isolated more frequently from during summer signifi cantly extended the of cut anthuriums is affected by temperature in the scape segments of bunched fl owers than vase life in two cultivars in most cases. The the room where the fl owers are placed. It was those of individual fl owers. The vase solution difference by BA treatment in ‘Red Leilani’ shown that cut anthuriums held at 14 or 22 °C contained silver to improve water uptake by was insignifi cant in the second summer, but had a longer vase life than those held at 8 °C the fl owers by protecting the cut stem ends the trend still showed that BA also extended (Paul, 1987; Paul and Chantrachit, 2001). In (Paul and Chantrachit, 2001). Silver also ex- the vase life in this cultivar. Overall, it was this study, the vase life during winter was not hibits oligodynamic action to inhibit microbial confi rmed that postimportation BA treatment considerably shorter overall than that during growth. Nonetheless, numerous numbers of was effective in delaying senescence of cut summer in both cultivars, indicating that the bacteria were isolated from individual vase anthuriums during summer, despite the treat- average temperatures during two winter tests solutions or sectioned scape segments. Ap- ment was made on the fl owers kept in the (16.1 and 17.8 °C) were not suffi ciently low parently, silver is not limiting the growth of shipping carton for 5 to 7 d after being packed to affect anthuriums. It was noteworthy, how- bacteria in the vase solution and subsequently at the nursery. The previous study (Shirakawa, ever, the vase life of BA-treated or nontreated in the xylem of the scape. 1964) demonstrated that cut anthuriums dipped fl owers of ‘Tropical Fire’ in the second winter One of the bacterial species that is likely to briefl y into a solution containing 10 µg·mL–1 was 66.0 or 67.4 d, the longest longevity ever cause decline in water uptake by the fl owers is of BA after 30-h shipping from Hawaii to measured in all experiments, despite the aver- X. axonopodis pv. dieffenbachiae, the causal Michigan showed only a marginal increased age RH during the experiment was as low as agent of bacterial blight of anthuriums. When in vase life. In this study, exogenous BA at 200 µg·mL–1 was applied as a spray. It was indicated Table 6. The extent of invasion by saprophytic bacteria into the scape of cut anthuriums (‘Tropic Fire’) that the effect by spraying BA was nearly equal when sprayed with BA and/or placed together in a base.z to that by dipping, and the maximum increase No. of scape segments in vase life was obtained at about 100µg·mL–1 colonized by saprophytic bacteriay or above (Paul and Chantrachit, 2001). Thus, Treatment After 4 weeks After 6 weeks it is essential to apply suffi cient concentra- Nontreated/individual 2.8 a 4.4 ab tions of BA to obtain the positive response in Nontreated/in a bunch 5.7 b 8.9 c treated fl owers. Sprayed with BA/individual 3.9 ab 4.4 ab The standard criteria for evaluating the vase Sprayed with BA/in a bunch 5.7 b 6.0 b life of cut anthuriums were based on visual zStarted in week 7, Summer 2002. spadix condition, spathe blueing, and the gloss yThe values were means of 10 replications. Based on two-way (treatment by time) ANOVA, the effects of of spathe (Paul, 1982). In this study, the vase treatment and time and their interaction were all signifi cant (P < 0.01). The means indicated with the same life was evaluated on visual discoloration of letters are not signifi cantly different according to Fisher’s protected LSD test (P = 0.05). Table 7. Vase life of cut anthuriums (‘Tropic Fire’) placed in vase solutions inoculated with the bacterial blight pathogens or the related bacteria.z Vase life (d)y Treatment In vase solution with 1% sucrose In vase solution without sucrose Not inoculated 25.5 25.3 Inoculated with a mixture of 3 strains of Xanthomonas spp. 27.0 23.7 Inoculated with a mixture of 3 strains of X. axonopodis pv. dieffenbachiae 26.0 24.0 zStarted in week 7, Summer 2002. yThe values were means of 10 replications. Based on two-way (treatment by addition of sucrose) ANOVA, both effects were not signifi cant with no signifi cant interaction between the effects.

1442 HORTSCIENCE VOL. 40(5) AUGUST 2005

AAugustBook.indbugustBook.indb 11442442 66/14/05/14/05 112:23:232:23:23 PPMM this pathogen was inoculated to the cut end of fl owers as an additional factor infl uencing the Wash., D.C. the leaf petiole of anthurium plants, the bac- effect of BA and the vase life in addition to Nooden, L.D. and A.C. Leopold. 1988. Senescence terium grew and spread inside the xylem and temperature, time of harvest, and cultivar. This and aging in plants. Academic Press, New caused wilting appearance in infected plants by factor may be signifi cant since cut anthuriums York. clogging up the xylem (Fukui et al., 1998). The are commonly placed together in vase water Norman, D.J. and A.M. Alvarez. 1989. A rapid method for the presumptive identifi cation of bacterium eventually establishes systemically when displayed at the retailer as well as at home. Xanthomonas campestris pv. dieffenbachiae and and kills the plants. In this study, the vase life Even at the nursery, cut anthuriums are usually other xanthomonads. Plant Dis. 73:654–658. was not affected when a mixture of three strains sorted by cultivar in the same water basket Paul, R.E. 1982. Anthurium (Anthurium andraeanum of X. axonopodis pv. dieffenbachiae, or three after harvest. Moreover, conditions during air- André) vase life evaluation criteria. HortScience strains of Xanthomonas spp., was inoculated freight can be the additional important factors. 17:606–607. to the vase solution. This indicates at least According to the representative of Japan Air Paul, R.E. 1987. Effect of storage duration and tem- that the blight pathogen or the related bacteria Cargo, temperature in the cargo compartments perature on cut anthurium fl owers. HortScience (most likely pathovars of X. campestris) sur- of airplanes during fl ight varies from near 0 to 22:459–460. viving in association with cut anthuriums and 15 °C depending on the location in the compart- Paul R.E. and T. Chantrachit. 2001. Benzyladenine and the vase life of tropical ornamentals. Post- subsequently spreading into the xylem of the ment. Although the shipping carton containing harvest Biol. Technol. 21:303–307. fl owers were not responsible for the reduced cut anthuriums used in this study was double- Paul, R.E., T. Higaki, and J.S. Imamura. 1992. Season vase life observed in bunched fl owers. It is layered, such low temperatures may have a and fertilization affect the postharvest fl ower life noteworthy that bunching the fl owers reduced great impact on anthuriums of cold-sensitive of anthurium. Scientia Hort. 49:125–134. the vase life only in BA-treated fl owers but not cultivars even when shipped during summer. Saile, E., J.A. McGarvey, M.A. Schell, and T.P. in nontreated fl owers. The precise mechanism All together, the results suggest that the vase Denny. 1997. Role of extracellular polysac- of this phenomenon and the involvement of life of cut anthuriums and the effect of BA can charide and endoglucanase in root invasion bacteria in loss of the effect of BA deserve be affected considerably by the conditions in and colonization of tomato plants by Ralstonia further investigations. all stages involved in shipment. solanacearum. Phytopthology 87:1264–1271. Salisbury, F.B. and C.W. Ross. 1992. Plant physi- Addition of sucrose at 1% in the vase so- ology. 4th ed. Wadsworth Publ. Co., Belmont, lution did not affect the vase life whether the Literatures Cited Calif. solution was inoculated with the bacteria or Fukui, H., A.M. Alvarez, and R. Fukui. 1998. Dif- Schaad, N.W., I.B. Jones, and W. Chun. 2001. not. It was reported that 4% sucrose in the vase ferential susceptibility of anthurium cultivars to Laboratory guide for identifi cation of plant solution signifi cantly extended the vase life of bacterial blight in foliar and systemic infection pathogenic bacteria. 3rd ed. Amer. Phytopathol. cut Eustoma fl owers (Huang and Chen, 2002). phases. Plant Dis. 82:800–806. Soc., St. Paul, Minn. Addition of sucrose into the vase solution at Gerasopoulous, D. and B. Chebli. 1999. Effects Shehata, S. 1995. The market for Hawaiian tropicals, 2.5% to 10% also signifi cantly increased the of pre- and postharvest calcium applications p. 20–23. In: K.M. Delate, and E.R. Yoshimura vase life of cut snapdragons, and the concentra- on the vase life of cut gerberas. J. Hort. Sci. (eds). Proc. 7th Hawaii Anthurium Ind. Conf. Biotechnol. 74:78–81. HITAHR 02.03.95, Univ. Hawaii. tion at 5% was most effective (Ichimura and Shirakawa, T., R.R. Dedolph, and D.P. Watson. Hisamatsu, 1999). However, addition of 2% Han, S.S. 2003. Role of sugar in the vase solution on postharest fl ower and leaf quality of oriental lily 1964. N-6 benzyladenine effects on chilling sucrose into the vase solution neither affected ‘Stargazer’. HortScience 38:412–416. injury, respiration and keeping quality of An- the longevity nor the size of postharvest oriental Huang, K-L. and W-S. Chen. 2002. BA and sucrose thurium andraeanum. Proc. Amer. Soc. Hort. lily (Han, 2003). These results may suggest increase vase life of cut Eustoma fl owers. Hort- Sci. 85:642–646. that 1% sucrose in the vase solution was Science 37:547–549. Van Staden, J., A.D. Bayley, S.L. Upford, and F.E. insuffi cient to induce measurable responses Ichimura, K. and T. Hisamatsu. 1999. Effects of Drewers. 1990. Cytokinins in cut carnation fl ow- in long-lasting cut anthuriums. It may be also continuous treatment with sucrose on the vase ers. VIII. Uptake, transport and metabolism of possible that the bacteria growing in the base life, soluble carbohydrate concentrations, and benzyladenine and the effect of benzyladenine ethylene production of cut snapdragon fl owers. derivatives on fl ower longevity. J. Plant Physiol. solution could have consumed sucrose. The 135:703–707. higher concentration of sucrose needs to be J. Jpn. Soc. Hort. Sci. 68:61–66. Kogure T. 1994. Marketing anthuriums in Japan, Vauterin, L., B. Hoste, K. Kersters, and J. Swings. tested in relation to the growth of bacteria in p. 27. In: K. M. Delate, and H. M. Tome (eds). 1995. Reclassifi cation of Xanthomonas. Intl. J. the vase solution in order to evaluate its effect HITAHR 02.02.94, Univ. Hawaii. Syst. Bacteriol. 45:472–489. on the vase life of cut anthuriums. Lennette, E. H. 1985. Manual of clinical microbi- Wilson, E.E., F.M. Zeitoun, and D.L. Fredrickson. This study identifi ed bunching of the ology, Fourth edition. Amer. Soc. Microbiol., 1967. 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