Rooting of healthy and CVC-affected 'Valência' sweet orange stem cuttings, through the use of plant regulators

Citrus variegated chlorosis (CVC) is a disease caused by Xylella fastidiosa. Using different concentrations of plant regulators, such as auxins (indole-3-butyric acid) and gibberellic acid biosynthesis-inhibitor (paclobutrazol), physiological rooting capacity of healthy and CVC-affected stem cuttings were evaluated in order to investigate the importance of plant hormone imbalance and xylem occlusion in plants with CVC. The percentages of dead, alive and rooted cuttings, cuttings with callus and mean number of roots per cuttings did not show statistical differences in response to the distinct concentrations of synthetic plant regulators. There were differences only between healthy and CVC-affected cuttings. This showed the importance of xylem occlusion and diffusive disturbances in diseased plants, in relation to root initiation capacity and hormonal translocation in the plant tissue.

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The Effect of Substrate pH on the Rooting of Rhododendron with Subirrigation

HortScience ◽

10.21273/hortsci.32.3.447a ◽

1997 ◽

Vol 32 (3) ◽

pp. 447A-447

Author(s):

Thomas Holt ◽

Brian K. Maynard ◽

William A. Johnson

Keyword(s):

Sulfuric Acid ◽

Tap Water ◽

Suitable Method ◽

Root Initiation ◽

Stem Cuttings ◽

Rooted Cuttings ◽

Average Displacement ◽

Water Ph ◽

Substrate Ph ◽

Different Levels

Subirrigation is a viable alternative to mist for the cutting propagation of many woody and herbaceous plants. However, poor success has been reported with rhododendron cuttings. This study evaluated the rooting of two Rhododendron cultivars in a subirrigation system maintained at two different levels of substrate pH. Stem cuttings of Rhododendron `PJM' and R. `Catawbiense album' were wounded, treated with Dip `n Grow (1:10 dilution), and rooted in subirrigated perlite subirrigated with tap water (pH 7.5), or tap water adjusted to pH 4.5 with weak sulfuric acid (1N H2SO4). Percent rooting and root ball displacement were recorded after 7 weeks. The pH of the subirrigation system dramatically affected root initiation and development. At pH 4.5 `PJM' cuttings rooted 100% with an average displacement of 7.6 ml; cuttings of `Catawbiense Album' rooted 88% with an average displacement of 12.1 ml. At pH 7.5, `PJM' cuttings rooted 52.5%, with an average displacement of 0.8 ml, while `Catawbiense album' rooted 73% with an average displacement of 2.5 ml. A root ball displacement of ≥3 ml was judged to be commercially acceptable for rooted cuttings of `PJM' rhododendron, ≥4.5 ml for `Catawbiense album'. At pH 7.5 only 15% of the `Catawbiense album' cuttings and none of the `PJM' cuttings produced commercially acceptable rooted cuttings. At pH 4.5, 83% of the `Catawbiense album' cuttings and 93% of the `PJM' cuttings were commercially acceptable. Subirrigation is a suitable method of irrigating rhododendron cuttings during rooting if a low substrate pH is maintained.

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Submist is Effective for Propagation of Korean Lilac and Inkberry by Stem Cuttings

HortTechnology ◽

10.21273/horttech03970-18 ◽

2018 ◽

Vol 28 (3) ◽

pp. 378-381

Author(s):

Bryan J. Peterson ◽

Stephanie E. Burnett ◽

Olivia Sanchez

Keyword(s):

Butyric Acid ◽

Woody Plants ◽

Root Biomass ◽

Potassium Salt ◽

Foliar Nutrients ◽

Stem Cuttings ◽

Rooted Cuttings ◽

Soilless Substrate

Although overhead mist revolutionized the propagation industry, it does suffer from potential drawbacks that include the application of large volumes of water, potentially unsanitary conditions, irregular misting coverage, and leaching of foliar nutrients. We explored the feasibility of submist as an alternative as it might avoid these problems by applying water exclusively from below the cutting, which is inserted basally into an enclosed rooting chamber. We propagated cuttings of korean lilac (Syringa pubescens ssp. patula) and inkberry (Ilex glabra) using both overhead mist and submist to compare effectiveness of the systems. Cuttings of korean lilac were wounded and dipped basally into 8000 mg·L−1 of the potassium salt of indole-3-butyric acid (K-IBA), and those in the overhead mist systems were inserted into coarse perlite. Cuttings of inkberry were wounded and treated with 5000 mg·L−1 K-IBA, and those in the overhead mist systems were inserted into 50:50 peat:perlite (by vol). Cuttings of korean lilac in the submist systems produced more than twice as many roots as cuttings in the overhead mist systems, with roots more than 2.6 times the length. Similarly, cuttings of inkberry in the submist systems produced more than three times the root counts and root lengths as cuttings in the overhead mist systems. For korean lilac, root dry weights averaged 58 mg for cuttings in the submist system, compared with only 18 mg among cuttings receiving overhead mist. Likewise, root dry weights averaged 70 and 7 mg for cuttings of inkberry propagated by submist and overhead mist, respectively. Rooted cuttings of korean lilac transplanted well into a soilless substrate, where they more than tripled their root biomass to 218 mg (vs. 59 mg for cuttings transplanted from overhead mist). We did not evaluate transplant performance of inkberry. Our results show that submist systems might merit consideration for the propagation of woody plants by leafy stem cuttings.

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AN ANATOMICAL STUDY OF ROOT INITIATION IN STEM CUTTINGS OF HYBRID LARCH

New Phytologist ◽

10.1111/j.1469-8137.1978.tb01610.x ◽

1978 ◽

Vol 81 (1) ◽

pp. 111-116 ◽

Cited By ~ 3

Author(s):

ALLAN JOHN

Keyword(s):

Anatomical Study ◽

Root Initiation ◽

Stem Cuttings ◽

Hybrid Larch

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Presence of Xylella fastidiosa in Sweet Orange Fruit and Seeds and Its Transmission to Seedlings

Phytopathology ◽

10.1094/phyto.2003.93.8.953 ◽

2003 ◽

Vol 93 (8) ◽

pp. 953-958 ◽

Cited By ~ 25

Author(s):

W.-B. Li ◽

W. D. Pria ◽

P. M. Lacava ◽

X. Qin ◽

J. S. Hartung

Keyword(s):

Vascular System ◽

Sweet Orange ◽

Xylella Fastidiosa ◽

Germination Rate ◽

Citrus Fruit ◽

Vascular Bundles ◽

Specific Amplification ◽

Root Grafts ◽

Citrus Seeds

Xylella fastidiosa, a xylem-limited bacterium, causes several economically important diseases in North, Central, and South America. These diseases are transmitted by sharpshooter insects, contaminated budwood, and natural root-grafts. X. fastidiosa extensively colonizes the xylem vessels of susceptible plants. Citrus fruit have a well-developed vascular system, which is continuous with the vascular system of the plant. Citrus seeds develop very prominent vascular bundles, which are attached through ovular and seed bundles to the xylem system of the fruit. Sweet orange (Citrus sinensis) fruit of cvs. Pera, Natal, and Valencia with characteristic symptoms of citrus variegated chlorosis disease were collected for analysis. X. fastidiosa was detected by polymerase chain reaction (PCR) in all main fruit vascular bundles, as well as in the seed and in dissected seed parts. No visual abnormalities were observed in seeds infected with the bacterium. However, the embryos of the infected seeds weighed 25% less than those of healthy seeds, and their germination rate was lower than uninfected seeds. There were about 2,500 cells of X. fastidiosa per infected seed of sweet orange, as quantified using real-time PCR techniques. The identification of X. fastidiosa in the infected seeds was confirmed by cloning and sequencing the specific amplification product, obtained by standard PCR with specific primers. X. fastidiosa was also detected in and recovered from seedlings by isolation in vitro. Our results show that X. fastidiosa can infect and colonize fruit tissues including the seed. We also have shown that X. fastidiosa can be transmitted from seeds to seedlings of sweet orange. To our knowledge, this is the first report of the presence of X. fastidiosa in seeds and its transmission to seedlings.

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Propagation of Citrus by Stem Cuttings and Seasonal Variation in Rooting Capacity

Pakistan Journal of Biological Sciences ◽

10.3923/pjbs.2001.1294.1298 ◽

2001 ◽

Vol 4 (11) ◽

pp. 1294-1298 ◽

Cited By ~ 6

Author(s):

Ram Chandra Bhusal . ◽

Fusao Mizutani . ◽

Doo-Gyung Moon . ◽

Kipkoriony Laban Rut .

Keyword(s):

Seasonal Variation ◽

Stem Cuttings ◽

Rooting Capacity

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A MODIFIED BEAN ROOT INITIATION TEST FOR AUXINS AND INHIBITORS

Canadian Journal of Plant Science ◽

10.4141/cjps67-047 ◽

1967 ◽

Vol 47 (3) ◽

pp. 263-268 ◽

Cited By ~ 2

Author(s):

P. A. Poapst ◽

A. B. Durkee ◽

S. H. Nelson

Keyword(s):

Cotyledonary Node ◽

Root Initiation ◽

Stem Cuttings ◽

Growth Inhibitors ◽

Bean Root

Removal of tissues above the cotyledonary node from leafy stem cuttings of Contender beans, after imbibition and prior to potting in root initiation tests, increased the sensitivity to growth inhibitors, and reduced the variation in control plants. Response to small amounts of auxin increased slightly and declined for larger amounts.

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EFFECTS OF POTASSIUM ACID PHOSPHATE, CANE SUGAR, ETHYL MERCURIC BROMIDE, AND INDOLYLACETIC ACID IN A TALC CARRIER ON THE ROOTING OF STEM CUTTINGS

Canadian Journal of Research ◽

10.1139/cjr41c-014 ◽

1941 ◽

Vol 19c (4) ◽

pp. 99-105

Author(s):

N. H. Grace

Keyword(s):

Acid Treatment ◽

Cane Sugar ◽

Stem Cuttings ◽

Organic Mercury ◽

Acid Phosphate ◽

Rooted Cuttings ◽

Indolylacetic Acid ◽

Beneficial Effects ◽

Plant Stem

Greenwood cuttings of Deutzia Lemoinei, Symphoricarpus albus, and Weigela rosea and dormant cuttings of Lonicera tatarica were treated with a series of 32 talc dusts containing potassium acid phosphate at concentrations of 0, 0.1, 1.0, and 10%, in combination with 0 and 10% cane sugar, 0 and 50 p.p.m. ethyl mercuric bromide, and 0 and 1000 p.p.m. indolylacetic acid. The lower concentrations of phosphate tended to increase rooting and reduce mortality of two of the species of greenwood cuttings whereas the 10% concentration was ineffective or injurious. However, this concentration was favourable to the rooting of dormant cuttings. Indolylacetic acid treatment increased the number of rooted cuttings and the number and length of roots. Beneficial effects were indicated for organic mercury and cane sugar treatments. However, these were attributed largely to the combinations with phosphate and indolylacetic acid. The results indicate that the effectiveness of dusts containing indolylacetic acid in the treatment of plant stem cuttings may be increased by the addition of nutrient and disinfectant chemicals.

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Container Type and Volume Influences Adventitious Rooting and Subsequent Field Growth of Stem Cuttings of Loblolly Pine

Southern Journal of Applied Forestry ◽

10.1093/sjaf/30.3.123 ◽

2006 ◽

Vol 30 (3) ◽

pp. 123-131 ◽

Cited By ~ 2

Author(s):

Anthony V. LeBude ◽

Barry Goldfarb ◽

Frank A. Blazich ◽

Jeff A. Wright ◽

Ben Cazell ◽

...

Keyword(s):

Loblolly Pine ◽

Stem Cuttings ◽

Root Mass ◽

System Quality ◽

Rigid Plastic ◽

Plastic Container ◽

Rooted Cuttings ◽

Field Growth ◽

Lower Root ◽

Container Type

Abstract Container type and size can influence rooting success, development, and subsequent field growth of loblolly pine rooted cuttings. To evaluate differences between containers, a series of two experiments were conducted comparing rooting in commercially available Jiffy forestry peat pelletsof various sizes to a rigid plastic container system considered to represent a commercially obtainable optimum. A third experiment was conducted to compare the effect of three volumes of Ray Leach Cone-tainers on rooting percentage and root system quality. The same three families were usedin experiments 1 and 2 where dormant and succulent cuttings were rooted, respectively. Succulent cuttings from a different set of three families were used in experiment 3. Rooted cuttings from experiments 2 and 3 also were field planted and evaluated for the effect of container type and sizeon 1st-year growth. In the first two experiments, rooting percentages of the best treatments (Jiffy pellets, 25–65, 30–65, 36–65, 36–75, and 42–65 mm) were equal to the controls, indicating that the peat pellets offer a practical alternative to rooting in rigidcontainers. Rooting percentages, however, declined in larger Jiffy pellets (42–80 mm and 50–95 mm pellets), but root masses of rooted cuttings were quite large. In the smaller Jiffy pellets, roots tended to grow into adjacent pellets resulting in lower root mass after the pelletswere harvested for planting. Lower root mass at preplanting equated to less root mass after 1 year in the field, despite the fact that the root systems were more horizontally developed than those produced in rigid containers. Rooting percentages and morphology were under genetic control andthere were statistically significant family × container interactions. Because these interactions were caused primarily by changes in magnitude rather than changes in ranks, a few of the containers could be used to optimize production for the limited number of genotypes tested here. Alternativemethods of producing rooted cuttings in Jiffy pellets are compared briefly with production systems in rigid containers and some important considerations are discussed. South. J. Appl.For. 30(3):142–146.

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Evaluation of the Genetic Structure of Xylella fastidiosa Populations from Different Citrus sinensis Varieties

Applied and Environmental Microbiology ◽

10.1128/aem.68.8.3731-3736.2002 ◽

2002 ◽

Vol 68 (8) ◽

pp. 3731-3736 ◽

Cited By ~ 16

Author(s):

Helvécio Della Coletta-Filho ◽

Marcos Antonio Machado

Keyword(s):

Population Structure ◽

Genetic Variation ◽

Citrus Sinensis ◽

Germ Plasm ◽

Sweet Orange ◽

Xylella Fastidiosa ◽

Random Amplified Polymorphic Dna ◽

Variable Number ◽

Chlorosis Resistance ◽

Northwest Region

ABSTRACT Xylella fastidiosa was isolated from sweet orange plants (Citrus sinensis) grown in two orchards in the northwest region of the Brazilian state of São Paulo. One orchard was part of a germ plasm field plot used for studies of citrus variegated chlorosis resistance, while the other was an orchard of C. sinensis cv. Pêra clones. These two collections of strains were genotypically characterized by using random amplified polymorphic DNA (RAPD) and variable number of tandem repeat (VNTR) markers. The genetic diversity (HT ) values of X. fastidiosa were similar for both sets of strains; however, HT RAPD values were substantially lower than HT VNTR values. The analysis of six strains per plant allowed us to identify up to three RAPD and five VNTR multilocus haplotypes colonizing one plant. Molecular analysis of variance was used to determine the extent to which population structure explained the genetic variation observed. The genetic variation observed in the X. fastidiosa strains was not related to or dependent on the different sweet orange varieties from which they had been obtained. A significant amount of the observed genetic variation could be explained by the variation between strains from different plants within the orchards and by the variation between strains within each plant. It appears, therefore, that the existence of different sweet orange varieties does not play a role in the population structure of X. fastidiosa. The consequences of these results for the management of sweet orange breeding strategies for citrus variegate chlorosis resistance are also discussed.

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