Stimulation of Adventitious Rooting in Cuttings of Four Herbaceous Species by Piperazine

Piperazine, a chemical used as buffer component, greatly promotedadventitious root formation in cuttings of sunflower (Helianthusannuus L.), pea (Pisum sativum L.), mung bean (Vigna radiataL.) and to a lesser extent in bean (Phaseolus vulgaris L.) seedlings.Piperazine was more effective in acidic pH. The studies withpiperazine analogues showed that any substantial modificationof the structure caused the chemical to be less effective, oreven inhibitory. Histological studies in sunflower hypocotylsdemonstrated that piperazine did not alter the timing of theinitial cell division. In the presence of piperazine, sunflowerhypocotyls failed to develop primary phloem fibres. Piperazineat the concentrations that promote rooting did not kill or damagethe tissue at the base of the hypocotyl. Compared to controls,piperazine treatment did not alter the proportion of primordiathat eventually developed into actively elongating roots. Sixdays after treatment 45% of the control roots in the basal sectionwere actively growing, compared to 51% in the piperazine. Therewas little evidence suggesting that the piperazine-induced promotionof rooting was caused by the removal of basal dominance in whichpiperazine killed the basal part of hypocotyl.Copyright 1995,1999 Academic Press Helianthus annuus, Phaseolus vulgaris, Pisum sativum, Vigna radiata, adventitious roots, mung bean, pea, piperazine, sunflower     

Effect of Non-auxin Chemicals on Translocation of Auxins in Cuttings of Phaseolus vulgaris (L.)

Indole, -naphthol, pyrogallol, coumarin, and salicylic acidinteracted with the auxins, IAA (indol-3yl-acetic acid), NAA(naphth-lyl-acetic acid), and 2, 4-D (2, 4-dichlorophenoxyaceticacid), supplied to the basal ends of cuttings of Phaseolus vulgaris(L.), giving synergistic or antagonistic effects in root formation.Antagonism in rooting was always associated with increased accumulationof radiocarbon from carboxyl-¹⁴C-labelled auxins in the topsof the cuttings. Distribution of auxin over a greater lengthof the cutting was accompanied by a reduction in root formation.The chemicals which synergized auxin-induced root formationdid not promote accumulation of radiocarbon of the exogenouslyapplied labelled auxins in the upper parts of the cuttings.     

Polyamines and Adventitious Root Formation in the Juvenile and Mature Phase of English Ivy

The involvement of polyamines during adventitious root formationwas evaluated using a de-bladed petiole rooting assay for theeasy-to-root juvenile and difficult-to-root mature phase ofEnglish ivy (Hedera helix L.). Auxin (NAA 0.1 mM) stimulatedroot formation in juvenile phase cuttings, but failed to promoterooting in the mature phase. The addition of putrescine, spermineor spennidine (1.0 mM) with or without NAA (0.1 mM) did notaffect the rooting response in either the juvenile or maturephase cuttings. There was a significant increase in endogenouslevels of putrescine and spermidine in NAA-treated cuttings,but the only significant difference between the root formingjuvenile and the non-root forming mature phase cuttings wasan increase in putrescine levels. In NAA-treated juvenile cuttings,the polyamine biosynthesis inhibitor DFMA (1.0 mM) promotedroot formation from 9.2 to 14.5 roots per cutting, while DFMO(1.0 mM) reduced root formation from 9.1 to 1.4 roots per cutting.The promotion of rooting by DFMA was completely reversed byputrescine (1.0 mM), but putrescine, spermine or spermidine(1.0 mM) could not reverse the inhibitory effect of DFMO. NeitherDFMA nor DFMO promoted root formation in mature phase cuttings.DFMA was also added to NAA-treated juvenile petioles at variousstages during the root formation process. DFMA promoted rootingwhen applied during the early stages of root induction (0–3d), but became inhibitory to root formation when applied duringthe organization (6–9 d) or root elongation stages (9–12d). Key words: Hedera helix, organogenesis, root initiation, polyamines, DFMA, DFMO     

Portulal: a rooting promoting substance in Portulaca leaves

A new bioassay which employs disbudded epicotyl cuttings takenfrom light grown Azukia seedlings (A. angularis) was devisedfor testing rooting promotion activity. By use of this method,the rooting promoting principle in leaves of Portulaca grandiflorawas isolated and identified with portulal which had been previouslyobtained. Portulal was reported as an inhibitor of rooting inetiolated Raphanus cuttings and has recently been determinedto be a bicyclic diterpene containing a perhydroazulene nucleus.Portulal promoted the adventitious root formation in severalkinds of plants, i.e. Azukia angularis, Vigna Catiang var. sinensis,Phaseolus Mungo and Raphanus sativus var. acanthiformis ‘Risodaikon’. The rooting process in Azukia and Raphanus cuttings seems toinclude at least two phases; a "preparatory phase" or a portulal-and gibberellin-sensitive phase and a "main phase" or an auxin-sensitiveand portulal-insensitive phase. ¹Contribution No. 16 from the Botanical Gardens, Faculty ofScience, University of Tokyo, Tokyo, Japan. (Received April 3, 1969; )     

Promotion of adventitious root formation by 4-chlororesorcinol: A polyphenol oxidase inhibitor

The extent of rooting in cuttings of Phaseolus vulgaris L., and Vigna radiata Wilcz. was affected by 4-chlororesorcinol, a polyphenol oxidase inhibitor. More root primordia and more roots were formed after 4-chlororesorcinol treatment both with and without 10^-5M Indole butyric acid. Promotion of rooting was observed also in cuttings of Elaeagnus pungens, Gypsophilia elegans and Kalanchoe blossfeldiana. The enhancement in bean and mung bean was accompanied by a concomitant wider spatial distribution of the primordia and the resulting adventitious roots. The formation of primordia in the treated cuttings was delayed by 12–24 hours, compared to untreated cuttings. The treatment was effective only when given during the first hours after the preparation of the cutting of bean and mung bean, suggesting involvement in the initiation stage. Hypocotyl extracts of mung bean cuttings, pretreated with 4-chlororesorcinol, exhibited reduced polyphenol oxidase activity. The inhibition was not reversed by washing of the treated extract in 50% acetone or by an overnight dialysis, suggesting tight or maybe even irreversible binding of the inhibitor to the enzyme.Abbreviations 4-CR 4-chlororesorcinol - IBA Indole butyric acid - PPO polyphenol oxidase     

Steroidal Oestrogens and Adventitious Root Formation in Phaseolus Cuttings

Solutions of oestrone, oestrone-phosphate, oestrone-sulphate,oestradiol and oestradiol-sulphate in the concentration range10^–3 mol m^–3 to 10^–7 mol m^–3 had noobservable morphological or anatomical effects on adventitiousroot formation in Phaseolus vulgaris hypocotyl, epicotyl andprimary leaf cuttings. Oestradiol-sulphate and oestrone-sulphatetreatments at 0.1 mol m^–3 significantly inhibited rootingin hypocotyls, and the inhibition was almost complete in epicotylsand primary leaves. In the latter, anomalous development ofvascular tissues was noted. However, neither oestrone-phosphateat 0.1 mol m^–3 nor direct application of up to 100 µgof the oestrogens to apices or primary leaves of explants modifiedthe pattern of root formation. The results are discussed withreference to the distributive and metabolic fates of the appliedsubstances. Phaseolus vulgaris L., bean, adventitious roots, steroidal oestrogens, translocation     

Stimulation of adventitious root formation in non-woody stem cuttings by uridine

Uridine strongly stimulated adventitious root formation in stem cuttings of sunflower (Helianthus annuus L.), mung bean (Vigna radiata L.) and common bean (Phaseolus vulgaris L.). A dose response curve of uridine induced rooting showed that the optimum concentration of uridine was 0.1 µM. At all concentrations employed, uridine had no significant effect on root elongation. The rooting response of stem cuttings to the optimal concentration of indole-3-butyric acid (10 µM) in combination with 0.1 µM uridine did not significantly differ from their response to either of these compounds when applied alone. However, the rooting response of the cuttings to sub-optimal IBA (0.01 µM) was significantly stimulated by uridine. These findings suggested that uridine may have stimulated rooting by increasing the sensitivity of the rooting tissue to auxin.     

Methyl gallate and its 3-glucoside promote rooting in bean cuttings

Methyl gallate stimulated adventitious root formation in cuttings of bean (Phaseolus vulgaris L.). This polyphenol was quickly metabolized into 3-glucosyl methyl gallate to such an extent that 4 h after application no methyl gallate was detected. The isolated glucoside when supplied exogenously at 0.5 mM also enhanced rooting; the effect was 2-fold greater than that of methyl gallate. The glucoside persisted in the cuttings for 72 h after treatment. Because methyl gallate is rapidly transformed to a stable glucoside, we suggest that the root stimulation effect could be ascribed to its glucoside.     

l-DOPA (l-3,4-dihydroxyphenylalanine) affects rooting potential and associated biochemical changes in hypocotyl of mung bean, and inhibits mitotic activity in onion root tips

A study was undertaken to explore the effect of l-DOPA (l-3,4-dihydroxyphenylalanine) on the rooting potential of hypocotyl cuttings of mung bean (Phaseolus aureus Roxb. var. SML-32) and related biochemical changes at the post-expression phase. At lower concentrations of (0.0001–0.1 mM) l-DOPA, there was no change in rooting potential, though the average number of roots per cutting and root length were significantly decreased (except at 0.0001 mM). However, at 1.0 mM concentration, a 50% inhibition in rooting potential was noticed and the root number and length were severely reduced. In contrast, at 2.5 mM l-DOPA, none of the hypocotyl cutting rooted. The decrease in rooting potential was associated with a significant effect on the biochemical changes measured in terms of protein and carbohydrate metabolism and activity of peroxidases. In the l-DOPA treated hypocotyl cuttings, there was a significant reduction in the protein and carbohydrate content, whereas activities of associated enzymes proteases and amylases decreased, particularly at higher treatment concentration (>1.0 mM). It indicated negative effect of l-DOPA on these two important metabolic processes. Likewise, activity of peroxidases also decreased in the l-DOPA treated hypocotyl mung bean cuttings thereby indicating its role in suppressing rhizogenesis as the enzyme is involved in lignification process during cell division. l-DOPA suppressed mitotic activity in the root tip cells of onion indicating thereby its interference with the cell division, which is required for the formation of new meristematic tissue during rhizogenesis. Based on the obtained results, it is concluded that l-DOPA interferes with the various biochemical processes in the mung bean hypocotyl cuttings thereby affecting their rooting potential.     

Caffeic acid affects early growth, and morphogenetic response of hypocotyl cuttings of mung bean (Phaseolus aureus)

Caffeic acid (CA) is one of the most common cinnamic acids ubiquitously present in plants and implicated in a variety of interactions including allelopathy among plants and microbes. This study investigated the possible interference of CA with root growth and the process of rhizogenesis in hypocotyl cuttings of mung bean (Phaseolus aureus=Vigna radiata). Results indicated that CA (0-1000 microM) significantly suppressed root growth of mung bean, and impaired adventitious root formation and root length in the mung bean hypocotyl cuttings. Further investigations into the role of CA in hampering root formation indicated its interference with the biochemical processes involved in rooting process at the three stages - root initiation (third day; RI), root expression (fifth day; RE), and post-expression (seventh day; PE) - of rhizogenesis. CA caused significant changes in the activities of proteases, peroxidases (PODs), and polyphenol oxidases (PPOs) during root development and decreased the content of total endogenous phenolics (TP) in the hypocotyl cuttings. The enhanced activity of PODs and PPOs, though, relates to lignification and/or phenolic metabolism during rhizogenesis; yet their protective role to CA-induced stress, especially during the PE phase, is not ruled out. At 1000 microM CA, where rooting was significantly affected, TP content was very high during the RI phase, thus indicating its non-utilization. The study concludes that CA interferes with the rooting potential of mung bean hypocotyl cuttings by altering the activities of PODs and PPOs and the endogenous TP content that play a key role in rhizogenesis.     

Interaction of abscisic acid and auxins in rooting of cuttings

Abscisic acid (ABA) at optimum concentrations promoted rootingof Phaseolus aureus ROXB. and Lycopersicon esculentum MILL,stem cuttings. In combination with IAA (indole-3-acetic acid)ABA has mostly given additive effects. Synergistic effect ofABA was noted on IBA (-indolebutyric acid)-induced rooting ofLycopersicon cuttings. Rooting of Phaseolus vulgaris L. cuttingscompletely failed when ABA (50 mg/liter) was applied in combinationwith IBA or NAA (-naphthaleneacetic acid). The results suggestthat abscisic acid may be an important natural regulator ofrooting in cuttings. (Received March 19, 1970; )     

Response of Cultured Embryos of Phaseolus vulgaris and Hordeum vulgare to Farnesol

Excised embryos of Phaseolus vulgaris incubated in a mediumcontaining 10 mg dm^–3 farnesol showed enhanced root growthwhereas the leaves remained rudimentary At lower concentrationsof exogenous farnesol normal leaf development occurred and rootgrowth was comparable to untreated cultures. Enhanced root growthalso occurred when excised embryos of Hordeum vulgare were treatedwith farnesol but only at 10 mg dm^–3 and this treatmentdid not prevent leaf growth X-ray micro-probe analysis of leavesrevealed an increased phosphorus content in P vulgaris and adecreased sulphur content in H vulgare in comparison to untreatedplants. Hordeum vulgare L., barley, Phaseolus vulgaris, bean, embryo culture, farnesol, X-ray microprobe analysis, root growth     

PROMOTING ACTIVITY OF TERPENIC LACTONES IN PHASEOLUS ROOTING AND THEIR REACTIVITY TOWARD CYSTEINE

Sesquiterpenoids which contain exomethylenes conjugated to -lactonecarbonyl-heliangine, helianginol, pyrethrosin and cyclopyrethrosinacetate—promoted the adventitious root formation on hypocotylsof cuttings taken from light-grown (1900 lux) 6-day old Phaseolusmungo seedlings, but their derivatives in which the methylene-lactone systems are reduced-to the saturated lactones—dihydroheliangine,hexahydro-heliangine, dihydrohelianginol, dihydrocyclopyrethrosinacetate and tetrahydrocyclopyrethrosin acetate—showedno effect on the root formation. As far as the present experiment is concerned, every substancewhich showed promoting activity in Phaseolus rooting reactedwith cysteine and formed an adduct, but any of the substancesincapable of promoting root formation did not react with cysteine.The correlation of promoting activity of terpenic lactones inPhaseolus rooting with their reactivity toward SH groups maythus be demonstrated. ¹ Contribution No. 14 from the Botanical Gardens, Faculty ofScience, University of Tokyo, Tokyo.     

Effect of malformin on adventitious root formation and metabolism of indoleacetic acid-2-14C by Phaseolus vulgaris

Malformin inhibited rooting on cuttings of Phaseolus vulgaris.IAA antagonized malformin-induced inhibition of rooting, butmalformin inhibited IAA-induced swelling on the base of thecuttings. It was suggested that IAA-induced swelling was mediatedby ethylene. Malformin did not inhibit transport of root-promotingsubstances from upper portions of the cuttings or polar transportof IAA-2-¹⁴C, nor did it alter the melting point of DNA or thebinding of DNA to histone. Although malformin appeared to alterthe metabolism of IAA-2-¹⁴C, the effect may have been the resultof a marked and selective stimulation of efflux of IAA-2-¹⁴Cmetabolites by malformin. Efflux of IAA or its metabolites maycontribute toward inhibition of rooting by malformin. ¹ Journal Paper No. 4688 of the Purdue Agricultural ExperimentStation. Supported in part by grant GB-7158 from the NationalScience Foundation. ² Present address: Botanisches Institut der Technischen UniversitätBraunschweig, 3300 Braunschweig, Humboldtstraße 1. (Received March 9, 1972; )     

Effect of malformin on phytochrome- and Ethrel-mediated responses

On etiolated cuttings of Phaseolus vulgaris malformin inhibitedseveral phytochromemediated responses. This included hypocotylhook-opening, leaf expansion, and inhibition of stem elongation.Malformin also inhibited anthocyanin synthesis by sorghum, buthad no effect upon lettuce seed germination in the light ordark. Malformin alleviated Ethrel-induced hook-retention, inhibitionof stem elongation, and root curvatures, but not Ethrel-inducedstimulation of lettuce seed germination in the dark. (Received February 19, 1975; )     

Morphological and physiological characterization of IAA-less-sensitive and IAA-sensitive phases in rooting of Azukia cuttings

In disbudded epicotyl cuttings taken from light grown 5-dayold Azukia angularis Phaseolus angularis) seedlings, all adventitiousrootlets appeared on the second day of incubation. No root primordiawere observed within the first 24 hr and no increase in thenumber of roots occurred after 48 hr. Puromycin (5.5?10^–5M), p-fluorophenylalanine (1?10^–3M),2-thiouracil (2.3?10^–4M) and 2,6-diaminopurine (2?10^–5M)inhibited rooting when applied to cuttings on the second day,but showed no inhibition when applied on the first day. Unlike these inhibitors, pyrithiamine (7.2?10^–5M) inhibitedrooting when it was applied to cuttings on the first day. A rooting promoting effect was observed with actinomycin D (2.4?10^–6M),2,4-dinitrophenol (3?10^–5M) and p-fluorophenylalanine(1?10^–4M) applied to the cuttings on the first day, whereasindoleacetic acid (1.7?10^–4M) showed its promoting effectmost effectively on the second day. ¹Contribution No. 17 from the Botanical Gardens, Faculty ofScience, University of Tokyo, Tokyo, Japan. (Received June 4, 1969; )     

脱落酸对绿豆下胚轴不定根发生的影响

以10^-4 mol/L脱落酸(ABA)处理绿豆种子24 h,在幼苗下胚轴长6 cm时,切除根部作为插条,研究ABA对插条不定根发生及插条基部细胞周期时相的影响。结果表明,ABA可促进下胚轴插条不定根发生,增加生根数和生根范围;ABA提高插条基部细胞色氨酸转氨酶、吲哚丙酮酸脱羧酶和吲哚乙醛脱氢酶的比活性,增加吲哚乙酸含量,同时进入细胞周期S期的基部细胞数目增加,促进DNA合成,有利于不定根的发生。     

Shoot RNA, cambrial activity and indolebutyric acid effectivity in seasonal rooting of juvenile and mature Ficus pumila cuttings

The seasonal influence on adventitious root formation was studied in woody leaf bud cuttings of Ficus pumila L., creeping fig. Juvenile cuttings rooted easily, whereas only mature cuttings treated with indolebutyric acid (IBA) exceeded 30% rooting. Greater rooting occurred in IBA-treated juvenile and mature cuttings than controls, regardless of the month each experiment was initiated. Seasonal changes influenced rooting in all treatments except IBA treated juvenile cuttings where percentage rooting was not affected. Higher vascular cambial activity and shoot RNA levels occurred in juvenile and mature forms during peak rooting periods. Highest RNA was recorded with juvenile materials during maximum rooting periods, while lowest RNA was observed in mature shoots during low rooting intervals.     

Comparative Fungitoxic and Plant Growth Regulating Properties of Triazole Derivatives

The triazol derivatives, S-3307, S-3308, triadimefon, triadimenoland paclobutrazol are recommended for use as either fungicidesor plant growth regulators. However, in varying degrees theyexhibit both properties. In a comparative study with 5 differentfungi, S-3308 followed by S-3307 were the most fungitoxic (invitro) whereas S-3307 and paclobutrazol were the most activeplant growth retardants in bean (Phaseolus vulgaris L.) andKentucky bluegrass (Poa pratensis L.). (Received September 24, 1985; Accepted November 26, 1985)