Ten-year growth and survival of Douglas-fir seedlings treated with plant growth regulating substances at transplant

Commercially available plant growth regulators (PGRs) or moisture retention gels, applied to the roots of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) before planting, can modify indole-3-acetic acid (IAA) levels in roots, root growth responses, and tree survival. We treated two different 1+0 stock types (PSB313B and PSB323) of Douglas-fir with indole-butyric acid (IBA), ethephon (Ethrel®), alginate, or a combination of IBA and alginate. New root growth and IAA levels in roots were measured 2 weeks after planting, and aboveground growth and tree survival were monitored over 10 growing seasons after planting. Treatment with IBA or the combination of IBA and alginate increased IAA conjugate and free IAA levels in roots, root growth, and tree survival. Alginate treatment alone increased new root growth and tree survival, but did not increase free IAA levels in roots. Ethrel® treatment increased free IAA levels and root growth, but had no effect on IAA conjugates or tree survival. A cost analysis suggests that use of certain PGRs or alginate decreases the cost required to attain target stocking and increased tree size. Our results suggest that application of PGRs or other root-promoting materials to the roots of Douglas-fir before planting has the potential to be a cost-beneficial method for increasing root growth and tree survival.

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Laminated Root Rot and Fumigant Injection Affect Survival and Growth of Douglas-Fir

Western Journal of Applied Forestry ◽

10.1093/wjaf/22.3.220 ◽

2007 ◽

Vol 22 (3) ◽

pp. 220-227 ◽

Cited By ~ 2

Author(s):

Constance A. Harrington ◽

Walter G. Thies

Keyword(s):

Tree Growth ◽

Growth Rates ◽

Root Rot ◽

Survival Rates ◽

Height Growth ◽

Douglas Fir ◽

Infection Level ◽

Growth And Survival ◽

Growing Seasons ◽

Tree Survival

Abstract Laminated root rot caused by Phellinus weirii is a significant disease of western conifers; it is important to understand the effects of the disease on tree growth and survival and, for some management objectives, to develop treatments that will reduce those effects. This study was conducted in a 47-year-old Douglas-fir (Pseudotsuga menziesii) stand in northwest Oregon. First, we evaluated the effects of root system infection on diameter and height growth. Growth rates were lowest in trees with high infection levels; root infection level affected diameter growth more than height growth. Second, we evaluated the effects of fumigation treatments on tree growth. The nine treatments were as follows: three dosages of methylisothiocyanate (MITC), four dosages of chloropicrin (trichloronitromethane), one dosage of Vorlex [20% MITC, 80% chlorinated C3 hydrocarbons (v/v)], and a control. The fumigants were applied by inserting them into holes drilled into the base of live trees. After nine growing seasons, all three of the treatments applying different dosages of MITC and the treatment applying the lowest dosage of chloropicrin had higher tree survival rates than the untreated control, and the growth rates in those four fumigation treatments were not significantly different from growth in the surviving control trees.

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Changes in Root IAA Content and Growth of Bareroot Conifers Treated with Plant Growth Regulating Substances at Planting

Journal of Environmental Horticulture ◽

10.24266/0738-2898-18.2.99 ◽

2000 ◽

Vol 18 (2) ◽

pp. 99-107

Author(s):

C.F. Scagel ◽

R.G. Linderman

Keyword(s):

Plant Growth ◽

Root Growth ◽

Lodgepole Pine ◽

Height Growth ◽

Douglas Fir ◽

Stem Diameter ◽

Diameter Growth ◽

Western Larch ◽

Growth And Survival ◽

Stem Diameter Growth

Abstract Growth and survival of bareroot plants after transplanting is partially a function of the plant's capacity to produce new roots. We conducted an experiment to determine whether application of plant growth regulators (PGRs) or moisture retention materials could modify IAA concentration in roots, new root growth, and above ground plant growth. Bareroot western larch, Englemann spruce, lodgepole pine, and Douglas-fir were treated with Stimroot, ethrel, Hormogel, or Alginate immediately before planting into a raised bed in a greenhouse. All treatments increased IAA content in roots of western larch, Englemann spruce, and Douglas-fir, but only treatments containing IBA increased free IAA in roots of lodgepole pine. Stimroot and Hormogel treatment increased height growth of western larch, lodgepole pine, and Douglas-fir, but only ethrel treatment increased height growth of Englemann spruce. All treatments increased stem diameter growth of western larch. Stimroot increased stem diameter growth rate of Englemann spruce and Douglas-fir, but stem diameter of lodgepole pine was unaffected by all treatments. Our results indicate that application of PGRs or other root-promoting materials to the roots of bareroot conifers before planting has the potential to be a cost-beneficial method for increasing root growth and decreasing transplant shock.

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Root Volume and Growth of Ponderosa Pine and Douglas-Fir Seedlings: A Summary of Eight Growing Seasons

Western Journal of Applied Forestry ◽

10.1093/wjaf/12.3.69 ◽

1997 ◽

Vol 12 (3) ◽

pp. 69-73 ◽

Cited By ~ 19

Author(s):

R. Rose ◽

D. L. Haase ◽

F. Kroiher ◽

T. Sabin

Keyword(s):

Pinus Ponderosa ◽

Ponderosa Pine ◽

Douglas Fir ◽

Stem Volume ◽

Coast Range ◽

Root Volume ◽

Growth And Survival ◽

Growing Seasons ◽

Early Results

Abstract This is the final summary of two studies on the relationship between root volume and seedling growth; early results were published previously. Survival, growth, and stem volume were determined for 2+0 ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) seedlings after 8 growing seasons. For each species, seedlings from three seedlots were assigned to one of three root-volume categories [<4.5 cm3 (RV1), 4.5-7 cm3 (RV2), and >7 cm3 (RV3) for ponderosa pine; <9 cm3 (RV1), 9-13 cm3 (RV2), and >13 cm3 (RV3) for Douglas-fir]. On a dry harsh ponderosa pine site on the eastern slopes of Mt. Hood in Oregon, where gopher and cattle damage decreased the number of seedlings, more seedlings in the highest root-volume category survived (70%) than in the smaller root-volume categories (62% and 50%). Douglas-fir on a good site in the Coast Range of Oregon showed significantly greater height and stem volume for the largest root-volume category, whereas annual shoot growth and survival did not differ. Root volume is one of several potentially useful criteria for predicting long-term growth and survival after outplanting. West. J. Appl. For. 12(3):69-73.

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Root growth and survivorship in cow manure and compost amended soils

Plant Soil and Environment ◽

10.17221/857/2012-pse ◽

2013 ◽

Vol 59 (No. 5) ◽

pp. 221-226 ◽

Cited By ~ 4

Author(s):

E. Baldi ◽

M. Toselli

Keyword(s):

Root Growth ◽

Prunus Persica ◽

Block Design ◽

Dry Weight ◽

Cow Manure ◽

Root Dynamics ◽

Growth And Survival ◽

Root Lifespan ◽

Growing Seasons ◽

Randomized Block Design

The effect of the application of compost and cow manure on nectarine (Prunus persica L.) root growth and survivorship was investigated in a commercial orchard during the growing seasons 2003, 2004 and 2005. Our main objective was to determine whether compost affects root dynamics differently than cow manure. The experiment was a complete randomized block design with four replicates of two treatments: cow manure and compost applied at planting in 2001 at 10 t dry weight (DW)/ha and from 2004 at the rate of 5 t DW/ha. The compost fertilization represented a yearly rate of 120 kg N/ha, while cow manure was approximately 80 kg N/ha/year. Both root growth and survival were evaluated at 20-day intervals during the growing season by the minirhizotron technique. Cow manure increased the production of new roots compared with compost (P ≤ 0.001). Roots were mainly produced at a depth of 21–40 cm for compost and 61–80 cm for cow manure. The root lifespan was longer in compost than in cow manure treated trees (P ≤ 0.05) and was strongly affected by depth. No differences were observed in root length and diameter.

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Fertilizing and mulching influence on the performance of four native woody species suitable for revegetation in subarctic Quebec

Canadian Journal of Forest Research ◽

10.1139/x94-302 ◽

1994 ◽

Vol 24 (12) ◽

pp. 2342-2349 ◽

Cited By ~ 15

Author(s):

Gilles Houle ◽

Patrice Babeux

Keyword(s):

Plant Growth ◽

Slow Release ◽

Woody Species ◽

Good Growth ◽

Plastic Mulch ◽

Growth And Survival ◽

Slow Release Fertilizer ◽

Growing Seasons ◽

Negative Effect ◽

Native Woody Species

Two plantations were established in the village of Whapmagoostui-Kuujjuaraapik to determine the effects of two types of fertilizer (fast or slow release) and two types of mulch (plastic or organic) on native woody species growth and survival in subarctic Quebec. In the first plantation, the species tested were Salixplanifolia Pursh, Alnuscrispa (Ait.) Pursh, Piceaglauca (Moench) Voss, and Pinusbanksiana Lamb. Four growing seasons after planting, cuttings of S. planifolia had the highest survival of all four species (96% in control plots) and a very good growth (4.8 mm and 5.7 cm growth in diameter and height, respectively). The performance of A. crispa was also very good (77% survival in control plots; 5.1 mm and 7.5 cm growth in diameter and height, respectively), while Piceaglauca (17% survival in control plots; 0.6 mm and −9.0 cm growth in diameter and height, respectively) and Pinusbanksiana (31% survival in control plots; 2.4 mm and 5.7 cm growth in diameter and height, respectively) performance was poor. The application of a slow-release fertilizer enhanced plant growth of all four species, but reduced the survival of A. crispa, particularly when a plastic mulch was used. Otherwise, mulching had no significant effect on either growth or survival of any of the other species. In the second plantation, established on a more exposed site, the survival of S. planifolia was lower (77% in control plots) than in the first plantation, and the application of a fast-release fertilizer there had a negative effect on plant growth. These latter results appear to be related to freezing injuries and winter killing of vegetative buds. Organic mulching did not influence plant growth on this second site, but the utilization of Alnus wood chips increased the survival of S. planifolia cuttings. We recommend the use of S. planifolia and also of A. crispa for revegetation purposes in subarctic Quebec. Application of a slow-release fertilizer can increase plant growth, but should not be combined with the use of plastic mulches, as plant survival is then negatively affected.

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991 REGULATION OF PLANT GROWTH RESPONSES TO LOW SOIL WATER POTENTIALS

HortScience ◽

10.21273/hortsci.29.5.571b ◽

1994 ◽

Vol 29 (5) ◽

pp. 571b-571

Author(s):

Robert E. Shar

Keyword(s):

Plant Growth ◽

Root Growth ◽

Growth Inhibition ◽

Shoot Growth ◽

Crop Improvement ◽

Plant Water ◽

Growth Responses ◽

Water Deficits ◽

Definitive Evidence ◽

Water Potentials

Plant water deficits usually result in severe inhibition of shoot growth, while root growth is less inhibited or even promoted. Recent advances in understanding the physiology of the differential responses of root and shoot growth to low water potentials will be reviewed. While it might be readily accepted that hormones arc important in transducing environmental conditions into growth responses, there is surprisingly little definitive evidence for the role of any hormone in regulating plant growth in soils of low water potential. Using maize seedlings as a model system, the increase in ABA that accompanies plant water deficits has been shown to be required for root growth maintenance, and also to play a role in shoot growth inhibition. The action of ABA in root growth maintenance appears to involve regulation of ethylene synthesis and/or sensitivity, while the mechanism of shoot growth inhibition is not known. Evidence that ABA acts as a root `signal controlling shoot growth in drying soil will also be considered. The importance of osmotic adjustment as a mechanism of growth maintenance at low water potentials has been questioned by suggestions that solute accumulation may be merely a consequence of stress-induced growth inhibition. Recent studies will be discussed which do not support this idea, and suggest that the response may be useful for crop improvement.

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Patterns of above- and below-ground response of understory conifer release 6 years after partial cutting

Canadian Journal of Forest Research ◽

10.1139/x01-190 ◽

2002 ◽

Vol 32 (2) ◽

pp. 255-265 ◽

Cited By ~ 57

Author(s):

Daniel D Kneeshaw ◽

Harry Williams ◽

Eero Nikinmaa ◽

Christian Messier

Keyword(s):

Root Growth ◽

Height Growth ◽

Douglas Fir ◽

Stem Growth ◽

Radial Increment ◽

Growth Responses ◽

Partial Cutting ◽

Size Classes ◽

Clear Cutting ◽

Advance Regeneration

An increased pressure to use silvicultural techniques not based on clear-cutting followed by planting has led to an interest in systems that take advantage of existing understory seedlings (advance regeneration). Earlier studies have suggested that following harvesting, understory seedlings may experience growth reductions before responding with growth increases. We hypothesize that this "growth shock" following release results because seedlings are ill adjusted to the new growing conditions and that this can be investigated through a comparison of growth in different parts of the tree over a 6-year period. This study compares the growth response of three size classes of lodgepole pine (Pinus contorta Dougl. ex Loud.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings to a partial overstory removal in relatively dry conifer forests of central British Columbia. Growth was evaluated in four parts of the studied trees: radial increment in roots, in the base of the stem, and in branches, as well as leader height growth extension. Our findings show that following release from the overstory, early growth increases were largest in the roots and stems irrespective of the species or the size class. Differences between the species were observed in greater absolute height growth for pine, whereas Douglas-fir invested in greater stem growth, especially in the larger individuals. Important differences also occurred temporally. Both species (and all size classes) responded with an immediate increase in root growth followed, after a 1-year delay, by an increase in stem growth. Branch radial increment (for pine) and leader height growth (both species), however, experienced 2 to 3 year growth reductions before responding. It is therefore suggested that individuals restore the rootshoot balance by greater initial investments to root growth to offset the increased transpiration losses associated with the greater light and higher temperature conditions and the relative changes in the photosynthetic versus nutrient uptake capacity following the canopy opening. Foresters may therefore be able to manipulate tree growth responses by using an appropriate degree of overstory removal or opening size.

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A Comparison of Herbicide and Mulch Mat Treatments for Reducing Grass, Herb, and Shrub Competition in the BC Interior Douglas-Fir Zone—Ten-Year Results

Western Journal of Applied Forestry ◽

10.1093/wjaf/20.3.167 ◽

2005 ◽

Vol 20 (3) ◽

pp. 167-176 ◽

Cited By ~ 8

Author(s):

G. J. Harper ◽

P. G. Comeau ◽

B. S. Biring

Keyword(s):

Soil Moisture ◽

Seedling Growth ◽

Height Growth ◽

Douglas Fir ◽

Effective Control ◽

Soil Drought ◽

Plastic Mulch ◽

Growth And Survival ◽

Growing Seasons ◽

Soil Moisture Availability

Abstract We present results from a study established in 1993 in the Interior Douglas-fir biogeoclimatic zone of southwestern British Columbia to test the effectiveness of several herbicide and mulch mat treatments for reducing grass, herbaceous, and shrub competition. The effectiveness of the preplant herbicide applications of hexazinone (Velpar L) at 2.1 kg ai/ha, glyphosate (Vision) at 2.1 and 1.0 kg ai/ha, and the installation of plastic mulch mats (Tredegar 90 × 90-cm mats) for controlling competing vegetation, improving seedling growth and survival of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings and improving soil moisture availability was evaluated. Ten-year results indicate that application of hexazinone and glyphosate enhanced the survival, diameter, and height growth of planted Douglas-fir seedlings. These herbicide treatments provided effective control of grass and herbaceous vegetation for three to four growing seasons. Plastic mulch mats did result in improvements in growth and survival, but these were not statistically different from untreated seedlings. The results of soil moisture monitoring from within the various treatments indicated delay in the onset of soil drought as a key determinant of the seedling growth improvement noted. West. J. Appl. For. 20(3):167–176.

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Talking with Strangers: Improving Serianthes Transplant Quality with Interspecific Companions

Forests ◽

10.3390/f12091192 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1192

Author(s):

Thomas E. Marler ◽

Ragan M. Callaway

Keyword(s):

Root Growth ◽

Agricultural Systems ◽

Growth Responses ◽

Growth And Survival ◽

Post Transplant ◽

Or Groups ◽

Relative Root Growth ◽

Companion Plants ◽

Harmful Effects ◽

Relative Root

Mixtures of species in natural or agricultural systems can increase the performance of individuals or groups relative to monocultures, often through facilitative mechanisms. Mechanisms include root communication by which plants can interrogate the identity of adjacent plants and respond negatively or positively. Alternatively, mixtures of species can ameliorate the harmful effects of soil biota that are pronounced in monocultures, thereby improving plant productivity. Limited investments into roots by shade-grown Serianthes plants in nurseries have been correlated with reduced survival after transplantation to forested habitats. We used companion container cultures in two studies to determine if heterospecific neighbor, or “stranger” roots could experimentally increase the root growth of Serianthes grandiflora plants used as surrogates for the critically endangered Serianthes nelsonii. In one study, native sympatric eudicot and pteridophyte companions increased relative root growth and conspecific companions decreased root growth in comparison to control plants that were grown with no companions. In a second study, the phylogeny of companion plants elicited different root growth responses following the order of congeneric < eudicot = monocot < gymnosperm < pteridophyte. We propose the use of stranger roots that are experimentally maintained in production containers as a passive protocol to improve relative and absolute root growth, leading to improved post-transplant growth and survival of container-grown Serianthes plants.

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Zinc availability modulates plant growth and immune responses via AZI1

10.1101/166645 ◽

2017 ◽

Cited By ~ 1

Author(s):

Nadia Bouain ◽

Santosh B. Satbhai ◽

Chorpet Saenchai ◽

Guilhem Desbrosses ◽

Pierre Berthomieu ◽

...

Keyword(s):

Plant Growth ◽

Immune Responses ◽

Root Growth ◽

Molecular Basis ◽

Allelic Variation ◽

Zinc Level ◽

Growth Responses ◽

Balance Of Plant ◽

Living Organisms

AbstractZinc is an essential micronutrient for all living organisms and is involved in a plethora of processes including growth and development, and immunity. However, it is unknown if there is a common genetic and molecular basis underlying multiple facets of zinc function. Here we used natural variation in Arabidopsis thaliana to study the role of zinc in regulating growth. We identify allelic variation of the systemic immunity gene AZI1 as a key for determining root growth responses to low zinc conditions. We further demonstrate that this gene is important for modulating root growth depending on the zinc and defence status. Finally, we show that the interaction of the immunity signal azelaic acid and zinc level to regulate root growth is conserved in rice. This work demonstrates that there is a common genetic and molecular basis for multiple zinc dependent processes and that nutrient cues can determine the balance of plant growth and immune responses in plants.

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