and G.J. Hochmuth (eds.). Vegetable pro- erbaceous perennial duction guide for Florida. Fla. Coop. Ext. Stratification have increased in popular- Serv. Circ. SP-170. Improves and Is H ity and use in the ornamen- Kidder, G., E.A. Hanlon, and G.J. tal landscape, particularly in the past 2 Hochmuth. 1989. IFAS standardized fer- Likely Required decades. Coincident with the surge of tilization recommendations for vegetable interest, many promising, new herba- crops. Fla. Coop. Ext. Serv. Spec. Ser. SS- for Germination ceous have been released, some SOS-907. successfully brought into cultivation Kunkel, R., N. Holstad, and T.S. Russell. of Aconitum from the wild for the first time, such as 1973. Mineral element content of potato several clones of the blue plants and tubers vs. yields. Amer. Potato sinomontanum (Corydalis flexuosa) from Sichuan, J. 50:275–282. China (Rix, 1993). Species of monkshood (Aconi- Livingston-Way, P., G. Hochmuth, E. Michael S. Dosmann Hanlon, A. Tilton, D. Bottcher, B. Reck, tum spp.) are valued in the horticul- and J. Konwinski. 1997. Assessment of tural trade for their late summer and agricultural BMPs in the tri-county agri- autumn dark blue to purple floral dis- cultural area of northeast Florida. Univ. ADDITIONAL INDEX WORDS. monkshood, plays and finely textured, divided leaves Fla. Coop. Ext. Serv. Misc. Publ. sexual propagation, dormancy, reminiscent of delphinium (Del- herbaceous landscape plants phinium) also in the Ranunculaceae. Locascio, S.J. and H.L. Breland. 1963. Irish potato yield and leaf composition as While the contains about 100 SUMMARY. Aconitum sinomontanum is species of annual, biennial and peren- affected by dolomite and phosphorus. Soil a robust perennial monkshood native Crop Sci. Soc. Fla. Proc. 23:95–99. nial herbaceous plants, only a few are to China that shows promise as a found in cultivation. Native to Eu- Rhue, R.D., D.R. Hensel, T.L. Yuan, and cultivated ornamental. However, nothing has been reported about the rope, the common monkshood (A. W.K Robertson. 1981a. Response of pota- napellus) may be the most frequently toes to soil and fertilizer phosphorus in germination requirements of the northeast Florida. Soil Crop Sci. Soc. Fla. species, and little is known about the grown of the species, having the gen- Proc. 40:58–61. requirements of the genus as a whole. eral attributes and characteristics of The objective of this study was to test the genus and reaching about 4 ft (1.2 Rhue, R.D., D.R. Hensel, T.L. Yuan, and the influence of stratification (moist m) in height. Others encountered in- W.K Robertson. 1981b. Ammonium or- prechilling) on germination of A. clude the asian azure monkshood (A. thophosphate and ammonium sinomontanum seeds. The seeds were carmichaelii), the european yellow polyphosphate as sources of phosphorus from wild-collected plants of identical for potatoes. Soil Sci. Amer. J. 45:1229– wolfsbane (A. lamarckii) and the hy- provenance growing at the Arnold brid bicolor monkshood (A. 1233. Arboretum (Jamaica Plain, Mass.). ×cammarum). Witzig, J.D. and N.L. Pugh. 2000. Florida After harvest and before stratification, seeds were stored dry at 38 °F (3.3 In September 1994, during a agricultural statistics. Vegetable summary. ° North America China Explora- Fla. Agr. Stat. Serv., Orlando. C) and percentage germination was assessed after seeds were stratified, tion Consortium (NACPEC) expedi- Yuan, T.L., D.R. Hensel, R.S. Mansell, also at 38 °F, for 0, 21, 42, or 84 tion, several plants of A. sinomontanum and R.D. Rhue. 1985a. Yield and nutrient days. It is likely that stratification is were found on Wudang Shan, Hubei content of potato on a sandy Humaquept required for seeds of this species to Province (lat. 32°23'43" N, with high levels of accumulated Ca and P. germinate, as unstratified seeds failed long.111°00'13" E), at an altitude of Soil Crop Sci. Soc. Fla. Proc. 44:68–71. to germinate through the duration of 4272 ft (1302 m), growing among the experiment (73 days). The highest wild english or persian walnut (Juglans Yuan, T.L., D.R. Hensel, and R.S. Mansell. level of germination (90.8%) was 1985b. Nutrient status of a sandy achieved after 84 days of stratifica- regia), chinese chestnut (Castanea Humaquept under long-term potato culti- tion, and as length of stratification mollissima), and Lindera obtusiloba. vation. Soil Crop Sci. Soc. Fla. Proc. 44:93– increased, so did percentage germina- As the fruit had not yet matured, sev- 97. tion and indices of peak value and eral young plants from the same popu- germination value. Days to maximum lation were collected under the num- germination decreased with additional ber WD 067. Although this species days of chilling. Growers wishing to was described in 1935 (Nakai, 1935), germinate seed of this species should this collection likely represents its only stratify seed for 3 months to achieve introduction to cultivation. the highest level of germination. Some of these original plants (394- 95 MASS) are growing at the Arnold Arboretum of Harvard University. The species shows potential for introduc- Putnam Research Fellow, The Arnold Arboretum of Harvard University, 125 Arborway, Jamaica Plain, MA tion as a cultivated ornamental, par- 02130. ticularly after further evaluation and Appreciation is extended to the staff of the Dana selection. While plants on Wudang Greenhouse of the Arnold Arboretum, for their assis- Shan were observed to be only 3.3 ft (1 tance during the experiment, and David Cox for statis- tical assistance. I also thank Peter Del Tredici, Michael m) in height, plants under cultivation Evans, Jeffery Iles and two anonymous reviewers for at the Arnold Arboretum ultimately their constructive comments and suggestions. produce erect stems up to 7.2 ft (2.2

G July–September 2002 12(3) 423 RESEARCH REPORTS

Table 1. Percentage germination (PG), days to complete germination (DG), from 63 to 92 °F (17.2 to 33.3 °C), and log-transformed indices of peak value (PV+1) and germination value and the mean temperature was 74 ± (GV+1) of Aconitum sinomontanum seeds germinated after 0, 21, 42, or 84 d of 5.5 °F (23.3 ± 3.1 °C). ° ° stratification (moist prechilling) at 38 F (3.3 C). Each value is the mean of 16 Percentage germination (PG), replications. defined as the percentage of seeds that showed emergence of either a radicle Stratification period Dependent variable or hypocotyl, was recorded every 3 to 5 d for each unit (container). At the (d) PG (%) DG (d) log (PVz+1) log (GVy+1) conclusion of the experiment (9 Feb. 0 0.0 ------2001) final PG and number of days 21 41.5 20.9 0.506 0.73 until maximum germination was de- 42 72.8 14.4 0.891 1.55 termined for each container. Peak value 84 90.8 11.0 1.863 2.80 (PV) and germination value (GV) for Significancex 0.0001 0.0001 0.0001 0.0001 each container were also calculated after Czabator (1962). For each day of zPeak value = the maximum ratio of cumulative germination percentage and the number of days from the beginning of the germination test. recording, cumulative PG is divided yGermination value = the product of the peak value and the mean daily germination percentage. by the number of days of germination. x Levels of significance for observations from analysis of variance. The maximum value obtained during the course of the experiment is se- m). Because of their size, the culti- velop rapidly to dehisce and expel seeds, lected as the PV, and is an index of vated plants should be provided with and the indeterminate shoots bear both germination vigor. The mean daily support, just as the plants in the wild ripened fruit and flowers at the same germination (MDG) is an expression are supported by neighboring shrubs time. Therefore, to obtain sufficient of vigor over time. It is the average and herbs. The finely textured, dark mature seeds for the study, collections number of seeds germinated per day green vegetation provides ornamental were made (from mature, basal-most over the test period (ending on the last interest through spring and summer. follicles) on four dates in 2000: 11 day of germination). The germination Anthesis begins in late August or early Oct., 27 Oct., 7 Nov., and 28 Nov. value combines these two values (GV September and floral development pro- After seeds were shaken loose of the = PV × MDG) into a single index. Both ceeds acropetally through November. follicles, they were placed in sealed PV and GV are useful in assessing Flowers are deep blue to purple and containers and stored in a refrigerator treatment effects because multiple ° are produced in multiple racemes up maintained at 38 F. components of germination can be to 7.9 inches (20 cm) in length. On 28 Nov. 2000, 64 individual characterized at once (Couvillon, × × Recommendations for propaga- plastic containers [3.5 3.5 3.25 2002; Dosmann et al., 2000). Before × × tion of this species are unknown, al- inches (8.9 8.9 8.3 cm)], with analysis and interpretation, PV and though propagation of other species drainage holes, were filled with sub- GV were transformed on a log scale, of monkshood is generally through strate [Fafard Germination Mix (super but because some values of PV and GV division of roots. Germination of fine), Agawam, Mass.], saturated with were zero, it was necessary to add the monkshood seed is reported to be tap water, and placed on a greenhouse value of 1 to each indexed value before difficult (Still, 1994). Armitage (1997) bench to dry overnight. On 29 Nov., log transformation. Thus, the values attributes this difficulty to the onset of 25 seeds were sown on the surface of represent log (PV+1) and log (GV+1). deep dormancy during ripening, and each container. A thin layer of about Analysis of variance (ANOVA), based he recommended sowing seed imme- 0.12 in (about 3 mm) of milled Sphag- on a completely randomized design, diately after collection. Stratification num peat moss was placed over the was performed on the data, and linear ° ° (moist prechilling) at 41 F (5 C) or surface of each container, and tap wa- and nonlinear regression were fitted as lower for 6 weeks has been recom- ter was gently applied overhead to wet appropriate. mended to break such dormancy the peat moss and seeds. There were (Hartmann et al., 1997). In other cases, four stratification treatments: 0, 21, Results and discussion germination of several Himalayan spe- 42 and 84 d. Units in the unstratified There was a significant effect of cies of monkshood (A. heterophyllum treatment were placed directly on a stratification treatment for all depen- and A. balfourii) was improved or greenhouse bench that received supple- dent variables (Table 1). None of the stimulated after treatment with gib- mental light using 100-W incandes- seeds in any of the unstratified con- berellic acid (GA3) (Pandey et al., 2000; cent bulbs to extend the daily photo- tainers germinated, despite observa- Prasad, 1999; Singh et al., 2000). The period to 12 h. The remaining units tion for 73 d. While it is likely that objective of this study was to deter- were sealed in plastic bags (to prevent periods of stratification less than 21 d mine the response of germination to desiccation) and placed in a walk-in would be sufficient to fulfill some of stratification in A. sinomontanum. refrigerator set at 38 °F. At the comple- the seeds’ dormancy requirements, tion of each stratification treatment, Materials and methods longer periods improved both PG and the appropriate units were removed time to germination. Extending the Seed was collected from a uni- from the refrigerator and randomly duration of chilling from 21 d to 84 d form, single-accession (394-95 MASS) placed on the same greenhouse bench. increased germination from 41.5% to planting of three A. sinomontanum Water was supplied daily by overhead 90.8%, and also decreased the number plants of growing at the Arnold Arbo- irrigation with tap water. Ambient tem- of days to maximum germination from retum. After flowering, follicles de- peratures in the greenhouse ranged 20.9 d to 11.0 d. Stratification period

424 G July–September 2002 12(3) Fig. 1. Influence of which is assumed to be genetically 0, 21, 42, or 84 d uniform, seeds of different prov- stratification (moist enances may respond differently. prechilling) at 38°F (3.3°C) on (A) percentage germina- Literature cited tion, (B) log- transformed peak Armitage, A. 1997. Herbaceous peren- nial plants: A treatise on their identifica- value [log(PV+1)] nd and (C) log- tion, culture and garden attributes. 2 transformed germi- ed. Stipes Publ., Champaign, Ill. nation value Baskin, C.C. and J.M. Baskin. 1998. [log(GV+1)] of Seeds: Ecology, biogeography, and evo- germinated Aconi- lution of dormancy and germination. tum sinomontanum Academic Press, San Diego, Calif. seeds. Peak value is the maximum ratio Couvillon, G.A. 2002. Cercis canadensis of cumulative L. seed size influences germination rate, germination per- seedling dry matter, and seedling leaf centage and the area. HortScience 37:206–207. number of days Czabator, F.J. 1962. Germination value: from the beginning An index combining speed and com- of the germination pleteness of pine seed germination. For. test. Germination Sci. 8:386–396. value is the product of the peak value Dosmann, M.S., J. K. Iles, and M.P. and the mean daily Widrlechner. 2000. Stratification and germination per- light improve germination of katsura centage. Stratifica- tree seed. HortTechnology 10:571– tion was significant 573. at P ≤ 0.001 for final germination per- Hartmann, H.T., D.E. Kester, F.T. centage (R2 = 0.963), Davies, and R.L. Geneve. 1997. Plant 2 propagation: Principles and practices. log(PV+1) (R = th 0.990), and 6 ed. Prentice Hall, N.J. log(GV+1) (R2 = Nakai, T. 1935. Species Jeholenses 0.976). Each point generis Aconiti, cum adnotationibus de represents a single speciebus affinitatis, nec non value. descriptionibus specierum et varietatum novarum in China boreali, Manshuria, et and the log-transformed PV and GV deep complex MPD, however the ap- Korea detectarum, p. 139–163. In: T. indices were clearly characterized by a plication of GA has no effect. Based Nakai, M. Honda, and M. Kitagawa (eds.). linear relationship with length of strati- Contributio ad cognitionem floræ upon the results of this study, seeds of mansuricæ. University Press, Tokyo. fication, the longest stratification peri- A. sinomontanum can be classified as ods having the greatest values (Fig. 1). having either intermediate or deep Pandey, H., S.K. Nandi, M. Nadeem, and However, longer periods of stratifica- complex MPD; the exact classification L M.S. Palni. 2000. Chemical stimulation tion are unlikely to significantly in- would depend on their response to of seed germination in Aconitum crease PG (Fig. 1) and they are un- GA. Because seed dormancy in other heterophyllum Wall. and A. balfourii Stapf.: likely to decrease days to maximum Important Himalayan species of medicinal species of monkshood can be removed value. Seed Sci. Technol. 28:39–48. germination much further. Thus, peri- with GA (Pandey et al., 2000; Prasad, ods of stratification longer than those 1999; Singh et al., 2000), and thus Prasad, P. 1999. Enhancement of seed tested here seem unnecessary for most classified as having intermediate com- germination of Podophyllum hexandrum commercial or research propagation plex MPD, further research may show Royle and Aconitum heterophyllum Wall by systems, as obtaining over 90% germi- that A. sinomontanum has the same different treatments. J. Hill Res. 12:102– 106. nation in less than 2 weeks may be type of dormancy. adequate. Growers and researchers wishing Rix, M. 1993. Corydalis flexuosa from According to Baskin and Baskin to propagate this species by seed can western China. The Plantsman 15:129– (1998), seeds of Ranunculaceae have do so with best results obtained after 130. rudimentary embryos and morpho- 84 d (3 months) of stratification (moist Singh, V., H. Nayyar, R. Uppal, and J.J. physiological dormancy (MPD). Seeds chilling). Though useful, there are Sharma. 2000. Effect of gibberellic acid on with intermediate complex MPD re- some limits to the interpretation of germination of Aconitum heterophyllum L. quire only cold stratification to re- these data. Aconitum sinomontanum Seed Res. 28:85–86. move dormancy, although gibberellic is not in cultivation and other prov- acid (GA) can substitute for the chill- Still, S.M. 1994. Manual of herbaceous enances of this species were not avail- th ing requirement. Cold stratification ornamental plants. 4 ed. Stipes Publ., able for this study. Because these re- Champaign, Ill. also removes dormancy in seeds with sults are based a single population

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