Low temperature effects on growth and physiology specific to a "grass-clump" dwarf wheat hybrid

The growth habit of "grass-clump" dwarf wheat plants can be affected by extremely short 16° treatments if given repeatedly. To localize the earliest growth responses in plants of one such hybrid (Mql × KF 1), the temperature sensitivity of plants of different ages, and the earliest temperature-induced changes in growth, development, and shoot physiology were investigated and compared with the responses of normal wheat plants.Mql × KF 1 plants growing at 26° responded to progressively shorter 16° treatments as they aged and plants exposed to 16° after 10 days growth at 26° were unable to recover from low temperature treatments of 3–5 days duration. Although shoot growth (as dry weight) of Mql × KF 1 stopped abruptly after 7 days at 16°, root growth (as dry weight) continued for at least 15 days. The rates of CO2 and water vapor exchange in individual leaves responded to low temperature similarly in both the dwarf and normal plants and did not markedly decrease until after 4 days at 16°. The most rapid low temperature response specific to Mql × KF 1 plants was cessation in primary tiller development immediately after the beginning of 16° exposure. It is proposed that the primary 16° effect is on the shoot meristematic region and that other changes in growth and physiology result from the lack of meristematic activity in the young growing region.

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EFFECTS OF IRRIGATION FREQUENCY ON PLANT GROWTH AND NUTRIENT LEVELS OF PINE BARK MEDIA

HortScience ◽

10.21273/hortsci.25.8.849c ◽

1990 ◽

Vol 25 (8) ◽

pp. 849c-849

Author(s):

T.E. Bilderback

Keyword(s):

Plant Growth ◽

Shoot Growth ◽

Chemical Properties ◽

Dry Weight ◽

Pine Bark ◽

Growth Responses ◽

Irrigation Frequency ◽

Foliar Tissue ◽

Physical And Chemical ◽

And Chemical Properties

Ilex × `Nellie R. Stevens' holly, Rhododendron sp. `Hinodegeri' azalea and Pyracantha coccinea, scarlet firethorn rooted cuttings were potted in • 3.81 containers. Irrigation was applied by Dram rings daily, or every 2,4,or 6 days. Approximately 1000 ml of water were applied at each irrigation. Three container media, including pine bark, and pine bark amended with either Terra-Sorb AG synthetic moisture extender incorporated at 1.2 kg/m3 or Aqua-Gro G wetting agent incorporated at 0.9 kg/m3 plus monthly drenches of 700 ml of 2500 ppm Aqua-Gro L were compared for physical and chemical properties and plant growth responses. Decreasing irrigation decreased pH, increased nutrient leachate levels, and increased foliar tissue levels of N,P,K,Ca,and Fe in holly and azalea. Pyracantha top and root dry weight was reduced at 4 and 6 day irrigation intervals, holly top growth was reduced by 6 day and azalea had greatest shoot growth at 2 day irrigation and was reduced by other irrigation frequencies. Top growth of all 3 species and root growth of pyracantha was reduced in the pine bark treatment.

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GROWTH ENHANCEMENT OF PHOTINIA × FRASERI WITH FOLIAR APPLICATIONS OF GROWTH REGULATORS

HortScience ◽

10.21273/hortsci.25.9.1125b ◽

1990 ◽

Vol 25 (9) ◽

pp. 1125b-1125

Author(s):

Allen D. Owings ◽

Steven E. Newman

Keyword(s):

Growth Regulators ◽

Growth Habit ◽

Dry Weight ◽

Growth Enhancement ◽

Lateral Branching ◽

Shoot Dry Weight ◽

Application Rates ◽

Meristematic Region ◽

One Year ◽

High Application

The action of foliar-applied uniconazole, paclobutrazol, dikegulac-sodium, ancymidol, 6-BA, GA4+7, and 6-BA + GA4+7 On container–grown Photinia × fraseri was studied over a one year period. Vegetative growth habit was evaluated at three month intervals. Shoot dry weight and histological examination of stern anatomy in the apical meristematic region was conducted at experiment termination.Several plant growth regulators, primarily uniconazole, 6-BA, 6-BA + GA4+7, and dikegulac-sodium, stimulated lateral branching. Linear increases in lateral branching occurred as application rates increased. High application rates of uniconazole and paclobutrazol created an asymmetrical growth habit and decreased dry weight accumulation.

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Salinity Tolerance of Seashore Paspalum Ecotypes: Shoot Growth Responses and Criteria

HortScience ◽

10.21273/hortsci.39.5.1138 ◽

2004 ◽

Vol 39 (5) ◽

pp. 1138-1142 ◽

Cited By ~ 29

Author(s):

Geungjoo Lee ◽

Ronny R. Duncan ◽

Robert N. Carrow

Keyword(s):

Salt Tolerance ◽

Salinity Tolerance ◽

Shoot Growth ◽

Cynodon Dactylon ◽

Growth Parameters ◽

Dry Weight ◽

Sand Culture ◽

Growth Responses ◽

Seashore Paspalum ◽

Absolute Growth

Evaluation of turfgrass salt tolerance is a basic strategy for selecting grasses that can be grown in areas with salt-affected water or soils. Our objectives were to determine the relative salinity tolerances of 32 grasses and to evaluate potential shoot-based criteria for assessing salinity tolerance. Shoot growth responses to salinity of 28 seashore paspalums (Paspalum vaginatum Swartz) and four bermudagrass [Cynodon dactylon (L.) × C. transvalensis Burtt-Davy] cultivars were investigated under solution/sand culture in a greenhouse. Turfgrasses were grown in a sea-salt amended nutrient solution. Salinity ranges were 1.1 to 41.1 dS·m-1 based on electrical conductivity of the solution (ECw). Selection criteria to assess salt tolerance were absolute growth at 1.1 (ECw0), 24.8 (ECw24), 33.1 (ECw32), and 41.1 dS·m-1 (ECw40); threshold ECw; ECw for 25% and 50% growth reduction based on ECw0 growth; and leaf firing (LF) at ECw0 and ECw40 (LF0 and LF40, respectively). Significant variations among 32 entries were observed for all shoot responses except threshold ECw. Ranges of values for shoot parameters were: inherent growth at ECw0 = 0.10 to 0.98 g dry weight (10-fold difference); growth at 24.8 dS·m-1 = 0.11 to 0.64 g; growth at 33.1 dS·m-1 = 0.09 to 0.54 g; growth at 41.4 dS·m-1 = 0.06 to 0.35 g; threshold ECW = 3.9 to 12.3 dS·m-1; ECw25 % = 14 to 38 dS·m-1; ECw50% = 22 to 43 dS·m-1; and LF40 = 7% to 41%. Results in this study indicated substantial genetic-based variation in salt tolerance within seashore paspalums. When evaluation of salt tolerance based on shoot responses is attempted at wide salinity levels up to 40 dS·m-1, all seven criteria exhibiting a significant F test can be used. Five entries (SI 92, SI 93-1, SI 91, SI 93-2, SI 89) were ranked in the top statistical grouping for all seven-growth parameters, followed by SI 90 ranked in six out of seven, and three paspalums (SI 94-1, `Sea Isle 1', and `Taliaferro') were ranked in five out of seven categories.

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Species and clonal variation in growth responses to waterlogging and submersion in the genus Salix

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000007430 ◽

1992 ◽

Vol 98 ◽

pp. 21-48 ◽

Cited By ~ 2

Author(s):

J. E. G. Good ◽

J. D. Winder ◽

E. Sellers ◽

T. G. Williams

Keyword(s):

Adventitious Roots ◽

Shoot Growth ◽

Intraspecific Variability ◽

Field Capacity ◽

Dry Weight ◽

Clonal Variation ◽

Growth Responses ◽

Salix Caprea ◽

Root Dry Weight ◽

Waterlogging Treatment

SynopsisThe responses of clones of a range of willow species to waterlogging and total submersion were compared in glasshouse experiments using specially constructed perspex tanks. Up to 13 weeks of waterlogging had little effect on form and growth rates of above-ground parts of two clones of Salix caprea L. and one clone of S. cinerea L. A second clone of S. cinerea responded differently to the other three clones by significantly increasing its leaf area and stem dry weight, suggesting that it is likely to be more tolerant of waterlogging.Plant parts below the waterline in the waterlogging treatment responded very differently to the same parts on control plants. All waterlogged plants developed hypertrophied lenticels within four weeks, followed by significant increases in stem diameter. In each clone most of the pre-existing root system died by the end of the waterlogging treatment. All clones formed adventitious roots which varied considerably between the species and to a lesser extent between clones within each species. In S. cinerea many short, fine, much-branched roots grew vertically upwards until they reached the water surface. In S. cinerea clone 90 they originated from both the pre-existing woody roots and from the hypertrophied lenticels on the submerged portions of the stems. In S. cinerea clone 12 they developed only from the hypertrophied lenticels. New roots produced by waterlogged S. caprea clones were long, sparsely branched and floated on or near the surface of the water. As in S. cinerea clone 90 they originated from both the pre-existing woody roots and the submerged hypertrophied lenticels. Whereas roots of the control plants of all clones were mostly ectomycorrhizal, those of the waterlogged plants had no mycorrhizae. In a second waterlogging experiment S. × sericans, S. viminalis and S. fragilis produced adventitious roots more like those of S. caprea than S. cinerea. Plants of all clones removed from the waterlogging treatment after 16 days and kept with their soil at field capacity thereafter produced many new roots from their old root balls. After 32 days waterlogging no such recovery occurred.Total submersion caused much more severe damage to the aerial parts of all tested species than waterlogging. After eight days submersion the shoot tips of S. fragilis were beginning to rot and by day 25 those of S. × sericans and S. viminalis were rotting too. Subsequently shoots developed from axillary buds which remained unaffected by rot throughout the experiment. In S. cinerea shoot growth ceased after eight days and terminal buds were formed which remained dormant but healthy throughout the experiment. Submersion caused progressive loss of pre-existing leaves in all species. Some newly formed leaves of each species developed epinastic deformities after > 16 days of submersion. All species except S. cinerea showed significant reductions in root dry weight after 32 days of submersion.In a second submersion experiment responses of three clones each of S. purpurea and S. viminalis were compared. Shoot growth was reduced significantly in four of the six clones after 14 days. No further reductions occurred in the next 14 days of submersion. Root dry weight also decreased, but it took 28 days of submersion to produce the greatest effect. The faster growing clones of each species were more adversely affected by submersion in terms of both reduced shoot growth and root growth than those which grew more slowly.Considerable intraspecific variability in responses to waterlogging and submersion have been shown in these experiments by clones not selected for their variation in flooding tolerance. This suggests that selection and breeding could lead to the development of flood-tolerant cultivars of species such as S. cinerea and S. caprea which are not noted for their ability to withstand inundation.

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Root and Shoot Growth Responses to Phosphate Fertilization in Container-grown Plants

HortTechnology ◽

10.21273/horttech.10.4.765 ◽

2000 ◽

Vol 10 (4) ◽

pp. 765-767 ◽

Cited By ~ 4

Author(s):

Timothy K. Broschat ◽

Kimberly A. Klock-Moore

Keyword(s):

Shoot Growth ◽

Dry Weight ◽

Fertilization Rate ◽

Growth Responses ◽

P Fertilization ◽

Shoot Ratio ◽

Root And Shoot Growth ◽

Phosphate Fertilization ◽

Bell Peppers ◽

Pentas Lanceolata

Areca palms [Dypsis lutescens (H. Wendl.) Beentje & J. Dransf.], spathiphyllums (Spathiphyllum Schott. `Figaro'), ixoras (Ixora L. `Nora Grant'), tomatoes (Lycopersicon esculentum Mill. `Floramerica'), marigolds (Tagetes erecta L. `Inca Gold'), bell peppers (Capsicum annuum L. `Better Bell'), and pentas [Pentas lanceolata (Forssk.) Deflers. `Cranberry'] were grown in a pine bark-based potting substrate and were fertilized weekly with 0, 8, 16, 32, or 64 mg (1.0 oz = 28,350 mg) of P per pot. Shoot, and to a much lesser extent, root dry weight, increased for all species as weekly P fertilization rate was increased from 0 to 8 mg/pot. As P fertilization was increased from 8 to 64 mg/pot, neither roots nor shoots of most species showed any additional growth in response to increased P. Root to shoot ratio decreased sharply as P fertilization rate was increased from 0 to 8 mg/pot, but remained relatively constant in response to further increases in P fertilization rate.

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GERMINATION AND VIGOUR IN SEEDS OF THE COWPEA IN RESPONSE TO SALT AND HEAT STRESS

Revista Caatinga ◽

10.1590/1983-21252019v32n115rc ◽

2019 ◽

Vol 32 (1) ◽

pp. 143-151 ◽

Cited By ~ 1

Author(s):

Luma Rayane de Lima Nunes ◽

Paloma Rayane Pinheiro ◽

Charles Lobo Pinheiro ◽

Kelly Andressa Peres Lima ◽

Alek Sandro Dutra

Keyword(s):

Salt Stress ◽

Heat Stress ◽

High Temperature ◽

Low Temperature ◽

Vigna Unguiculata ◽

Salt Concentration ◽

Dry Weight ◽

Germination Percentage ◽

Different Types ◽

Different Temperatures

ABSTRACT Salinity is prejudicial to plant development, causing different types of damage to species, or even between genotypes of the same species, with the effects being aggravated when combined with other types of stress, such as heat stress. The aim of this study was to evaluate the tolerance of cowpea genotypes (Vigna unguiculata L. Walp.) to salt stress at different temperatures. Seeds of the Pujante, Epace 10 and Marataoã genotypes were placed on paper rolls (Germitest®) moistened with different salt concentrations of 0.0 (control), 1.5, 3.0, 4.5 and 6.0 dS m-1, and placed in a germination chamber (BOD) at temperatures of 20, 25, 30 and 35°C. The experiment was conducted in a completely randomised design, in a 3 × 4 × 5 scheme of subdivided plots, with four replications per treatment. The variables under analysis were germination percentage, first germination count, shoot and root length, and total seedling dry weight. At temperatures of 30 and 35°C, increases in the salt concentration were more damaging to germination in the Epace 10 and Pujante genotypes, while for the Marataoã genotype, damage occurred at the temperature of 20°C. At 25°C, germination and vigour in the genotypes were higher, with the Pujante genotype proving to be more tolerant to salt stress, whereas Epace 10 and Marataoã were more tolerant to high temperatures. Germination in the cowpea genotypes was more sensitive to salt stress when subjected to heat stress caused by the low temperature of 20°C or high temperature of 35°C.

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Regulation of loquat fruit low temperature response and lignification involves interaction of heat shock factors and genes associated with lignin biosynthesis

Plant Cell & Environment ◽

10.1111/pce.12741 ◽

2016 ◽

Vol 39 (8) ◽

pp. 1780-1789 ◽

Cited By ~ 24

Author(s):

Jiao-ke Zeng ◽

Xian Li ◽

Jing Zhang ◽

Hang Ge ◽

Xue-ren Yin ◽

...

Keyword(s):

Heat Shock ◽

Low Temperature ◽

Temperature Response ◽

Lignin Biosynthesis ◽

Heat Shock Factors

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Canopy development and hydraulic function in Eucalyptus tereticornis grown in drought in CO2-enriched atmospheres

Functional Plant Biology ◽

10.1071/fp06338 ◽

2007 ◽

Vol 34 (12) ◽

pp. 1137 ◽

Cited By ~ 23

Author(s):

Brian J. Atwell ◽

Martin L. Henery ◽

Gordon S. Rogers ◽

Saman P. Seneweera ◽

Marie Treadwell ◽

...

Keyword(s):

Elevated Co2 ◽

Shoot Growth ◽

Co2 Enrichment ◽

Atmospheric Co2 ◽

Shoot Biomass ◽

Eucalyptus Tereticornis ◽

Growth Responses ◽

Ambient Conditions ◽

Long Distance ◽

Pipe Model

We report on the relationship between growth, partitioning of shoot biomass and hydraulic development of Eucalyptus tereticornis Sm. grown in glasshouses for six months. Close coordination of stem vascular capacity and shoot architecture is vital for survival of eucalypts, especially as developing trees are increasingly subjected to spasmodic droughts and rising atmospheric CO2 levels. Trees were exposed to constant soil moisture deficits in 45 L pots (30–50% below field capacity), while atmospheric CO2 was raised to 700 μL CO2 L–1 in matched glasshouses using a hierarchical, multi-factorial design. Enrichment with CO2 stimulated shoot growth rates for 12–15 weeks in well-watered trees but after six months of CO2 enrichment, shoot biomasses were not significantly heavier (30% stimulation) in ambient conditions. By contrast, constant drought arrested shoot growth after 20 weeks under ambient conditions, whereas elevated CO2 sustained growth in drought and ultimately doubled the shoot biomass relative to ambient conditions. These growth responses were achieved through an enhancement of lateral branching up to 8-fold due to CO2 enrichment. In spite of larger transpiring canopies, CO2 enrichment also improved the daytime water status of leaves of droughted trees. Stem xylem development was highly regulated, with vessels per unit area and cross sectional area of xylem vessels in stems correlated inversely across all treatments. Furthermore, vessel numbers related to the numbers of leaves on lateral branches, broadly supporting predictions arising from Pipe Model Theory that the area of conducting tissue should correlate with leaf area. Diminished water use of trees in drought coincided with a population of narrower xylem vessels, constraining hydraulic capacity of stems. Commensurate with the positive effects of elevated CO2 on growth, development and leaf water relations of droughted trees, the capacity for long-distance water transport also increased.

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The role of nematodes, fungi, bacteria, and abiotic factors in the etiology of apple replant problems in the Granite Belt of Queensland

Australian Journal of Experimental Agriculture ◽

10.1071/ea9941177 ◽

1994 ◽

Vol 34 (8) ◽

pp. 1177 ◽

Cited By ~ 32

Author(s):

SR Dullahide ◽

GR Stirling ◽

A Nikulin ◽

AM Stirling

Keyword(s):

Abiotic Factors ◽

Dry Weight ◽

Pratylenchus Penetrans ◽

Growth Responses ◽

Granite Belt ◽

Pathogenicity Tests ◽

Phosphorus And Potassium ◽

Orchard Soils ◽

Fusarium Tricinctum

Investigations of apple replant failure in the Granite Belt suggested that the problem had a complex etiology. Soil fertility was an important factor because apple seedlings grew best in replant soils with high levels of nitrogen, phosphorus, and potassium. Consistent improvements in the growth of apple seedlings were obtained when typical orchard soils were treated with fenamiphos, confirming that lesion nematode was also an important component of the disease complex. Pratylenchus penetrans had been recognised as a pathogen of apples, and pathogenicity tests showed that P. jordanensis, another species widely distributed in the Granite Belt, had similar effects. Growth responses of apple seedlings were greater when soil was pasteurised than when it was treated with fenamiphos, suggesting that root pathogens other than nematodes were involved in apple replant failure. However, the primary cause probably differed between orchards because soils did not respond in the same manner to pasteurisation and nematicide treatments. Pathogenicity tests with 14 bacteria associated with apple roots showed no effect on the growth of apple seedlings. However, Fusarium tricinctum, Cylindrocarpon destructans, and Pythium sp. were implicated in the problem because they were consistently recovered from discoloured roots. In a factorial experiment involving nematodes and fungi in pots, P. jordanensis, P. penetrans, E. tricinctum, and C. destructans reduced the dry weight of apple roots but there was no interaction between nematodes and fungi.

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