Studies in the ecology of Nothofagus cunninghamii Oerst. II. Phenology

1973 ◽  
Vol 21 (1) ◽  
pp. 79 ◽  
Author(s):  
TM Howard
Keyword(s):  
Seed Production ◽  
Seed Viability ◽  
Tree Age ◽  
Average Annual Rate ◽  
Continuous Growth ◽  
Apical Bud ◽  
Lateral Buds ◽  
Adult Trees ◽  
Rate Of Decay ◽  
Hills Area

After germination, seedling growth of Nothofagus cunninghamii results from spring flushing of lateral buds, combined at 4-5 years of age with continuous growth from an apical bud during summer. Adult trees all flush from lateral buds in spring. In addition occasional sporadic flushes occur in autumn, but decrease in frequency with increase in altitude. Within the first 4-5 years of life of Victorian N. cunninghamii seedlings, epicormic burl development with the proliferation of dormant buds commences. This epicormic burl is poorly developed on trees in the Surrey Hills area of northwestern Tasmania. It is suggested that burl formation may have been selected by more constant burning in Victoria, where trees able to coppice after fire have both higher growth rate and earlier seed production than seed-produced plants. Flowering of N. cunninghamii in Victoria is annual and seed production is generally high. Seed viability increases with tree age, and decreases with stand altitude. The average viability at 3300 ft is 45-50%, and production may be as high as 11 x 106 seeds per acre. The effective longevity in the field is 8-9 months, though dry stored seed at room temperature may germinate, with some viability loss, after 2½ years. The fall of litter in an N. cunninghamii forest is 6.5 tonnes per hectare per year, and the average annual rate of decay is 0.42. N. cunninghamii leaves live for just over 3 years, falling in autumn after the spring growth has matured.

Seed production of Pinus sylvestris after release cutting

2000 ◽  
Vol 30 (6) ◽  
pp. 982-989 ◽  
Author(s):  
Christer Karlsson
Keyword(s):  
Pinus Sylvestris ◽  
Seed Production ◽  
Seed Quality ◽  
Seed Viability ◽  
Tree Height ◽  
Tree Age ◽  
Cone Production ◽  
Crown Length ◽  
Viable Seeds ◽  
Individual Trees

The effects of release cutting on cone, seed production, and seed quality were investigated in 1995-1996 among Scots pine (Pinus sylvestris L.) seed trees in central Sweden. The effects of diameter, height, crown length, and age of trees on cone production were also examined. Cone and seed production were about five times higher in seed trees that had been released for 4 or 5 years, compared with control trees in the unreleased forest. Seed trees released for less than 3 years had about the same level of cone production as the controls. After release, the number of cones increased more in the lower part of the tree crowns than in the uppermost 2 m. The mean 1000-seed weight, seed viability, and number of viable seeds per cone were not significantly different between released and unreleased trees. In 1996, there were about eight times more cones than in 1995, probably because summer temperatures were higher in 1994 than in 1993, the years when the respective flower buds were initiated. Within the investigated range of diameters, 250-430 mm at breast height, a 10-mm increase in diameter was correlated with a 10% increase in mean cone production. However, the variation in cone production between individual trees was considerable. Tree height, length of green crown, and tree age showed no significant correlations with cone production.

scholarly journals Do applications of systemic herbicides when green fruit are present prevent seed production or viability of Alliaria petiolata (garlic mustard)?

2021 ◽  
pp. 1-17
Author(s):  
Leo Roth ◽  
José Luiz C. S. Dias ◽  
Christopher Evans ◽  
Kevin Rohling ◽  
Mark Renz
Keyword(s):  
Seed Production ◽  
Seed Viability ◽  
Early Spring ◽  
Alliaria Petiolata ◽  
Late Spring ◽  
Garlic Mustard ◽  
Viable Seed ◽  
Application Timing ◽  
Control Seed ◽  
Second Year

Garlic mustard [Alliaria petiolata (M. Bieb.) Cavara & Grande] is a biennial invasive plant commonly found in the northeastern and midwestern United States. Although it is not recommended to apply herbicides after flowering, land managers frequently desire to conduct management during this timing. We applied glyphosate and triclopyr (3% v/v and 1% v/v using 31.8% and 39.8% acid equivalent formulations, respectively) postemergence to established, second-year A. petiolata populations at three locations when petals were dehiscing, and evaluated control, seed production and seed viability. Postemergence glyphosate applications at this timing provided 100% control of A. petiolata by 4 weeks after treatment at all locations whereas triclopyr efficacy was variable, providing 38-62% control. Seed production was only reduced at one location, with similar results regardless of treatment. Percent seed viability was also reduced, and when combined with reductions in seed production, we found a 71-99% reduction in number of viable seed produced plant-1 regardless of treatment. While applications did not eliminate viable seed production, our findings indicate that glyphosate and triclopyr applied while petals were dehiscing is a viable alternative to cutting or hand-pulling at this timing as it substantially decreased viable A. petiolata seed production. Management Implications Postemergence glyphosate and triclopyr applications in the early spring to rosettes are standard treatments used to manage A. petiolata. However, weather and other priorities limit the window for management, forcing field practitioners to utilize more labor-intensive methods such as hand-pulling. It is not known how late in the development of A. petiolata these herbicides can be applied to prevent viable seed production. Since prevention of soil seedbank replenishment is a key management factor for effective long-term control of biennial invasive species, we hypothesized late spring foliar herbicide applications to second year A. petiolata plants when flower petals were dehiscing could be an effective management tool if seed production or viability is eliminated. Our study indicated that glyphosate applications at this timing provided 100% control of A. petiolata plants by 4 weeks after treatment at all locations, whereas triclopyr efficacy was inconsistent. Although both glyphosate and triclopyr decreased viable seed production to nearly zero at one of our three study locations, the same treatments produced significant amounts of viable seed at the other two locations. Our findings suggest late spring glyphosate and triclopyr applications should not be recommended over early spring applications to rosettes for A. petiolata management, as our late spring application timing did not prevent viable seed production, and may require multiple years of implementation to eradicate populations. Nonetheless, this application timing holds value in areas devoid of desirable understory vegetation compared to no management practices or mechanical management options including hand-pulling when fruit are present, as overall viable seed production was reduced to similar levels as these treatments.

scholarly journals Fungal colonizers and seed loss in lodgepole pine orchards of British Columbia

Botany ◽  
2019 ◽  
Vol 97 (1) ◽  
pp. 23-33
Author(s):  
Paul Y. de la Bastide ◽  
Jonathon LeBlanc ◽  
Lisheng Kong ◽  
Terrie Finston ◽  
Emily M. May ◽  
...  
Keyword(s):  
British Columbia ◽  
Seed Production ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Seed Viability ◽  
Molecular Approaches ◽  
Seed Loss ◽  
Natural Range ◽  
Fungal Microbiome ◽  
Host Tissues

Lodgepole pine (Pinus contorta var. latifolia Engelm. ex S. Watson) is an important lumber species in Canada, and seed orchards are expected to meet the increased demand for seed. However, seed production has been consistently low in the Okanagan region orchards of British Columbia, Canada. To determine whether the fungal microbiome contributes to seed loss, histological and molecular approaches were used. Seed production was studied at seven Okanagan orchards, all outside the natural range of lodgepole pine, and at one near Prince George, within its natural range. Seed losses were highest in the Okanagan, compared with Prince George. The role of fungal colonizers in consuming seed during the last stages of maturation is described. Fungal hyphae were frequently observed at all locations in developing seed, particularly once storage substances accumulated. Fungi identified from host tissues using molecular and morphological techniques included Alternaria, Cladosporium, Fusarium, Penicillium, and Sydowia. The opportunistic foliar pathogen Sydowia polyspora, which is known to have a variable biotrophic status, was detected at most orchards within different host tissues (seeds, needles, and conelets), in association with pollen, and in the air column. Reduced seed viability observed in Okanagan orchards is most likely due to a combination of factors, including composition of the fungal microbiome.

scholarly journals Potential Role of Sequential Glufosinate and Foramsulfuron Applications for Management of Fescues (Festucaspp.) in Wild Blueberry

2017 ◽  
Vol 31 (1) ◽  
pp. 100-110 ◽  
Author(s):  
Scott N. White ◽  
Shanthanu Krishna Kumar
Keyword(s):  
Field Study ◽  
Seed Production ◽  
Potential Role ◽  
Seedling Recruitment ◽  
Seedling Emergence ◽  
Seed Viability ◽  
Early Spring ◽  
Seedling Mortality ◽  
Wild Blueberry

Sheep and hair fescue are perennial, tuft forming grasses that spread by seed and form dense sods in wild blueberry fields. These sods compete with the crop for resources and hinder harvest. Field and greenhouse studies were conducted in 2015 to evaluate 1) the effect of sequential glufosinate and foramsulfuron applications on suppression of fescues in the greenhouse and field, and 2) efficacy of glufosinate and foramsulfuron on fescue seedlings when applied at 2, 4, 6, and 8 wk after seedling emergence in the greenhouse. Glufosinate applications at 750 and 1,005 g ai ha−1followed by foramsulfuron application at 35 g ai ha−1reduced fescue leaf number and biomass relative to foramsulfuron application alone in the greenhouse. In the field study, fescue flowering tuft density, tuft inflorescence height, seed production, and seed viability were reduced by foramsulfuron alone, but there was a trend towards lower seed production and tuft height when fescues were treated with glufosinate at 1,005 g ha−1followed by foramsulfuron. Foramsulfuron caused low seedling mortality at all application timings evaluated, but glufosinate caused >90% mortality in seedlings when applied at 2, 4, 6, or 8 wk after seedling emergence. Our results suggest that sequential applications of these herbicides are less effective under field conditions relative to results obtained in the greenhouse, though burndown glufosinate applications may have a role in reducing fescue seedling recruitment. Additional research should be conducted to determine the effect of early spring and autumn glufosinate applications on fescue seedling recruitment and suppression of established fescue tufts with subsequent foramsulfuron applications.

scholarly journals Flowering, Fecundity, Seed Germination, and Seed Viability of Viburnum opulus L. Cultivars

2009 ◽  
Vol 27 (1) ◽  
pp. 31-36
Author(s):  
Janine R. Conklin ◽  
James C. Sellmer
Keyword(s):  
Seed Germination ◽  
Seed Production ◽  
Seed Viability ◽  
Biological Traits ◽  
Limited Information ◽  
Viable Seed ◽  
Invasive Potential ◽  
Short Term ◽  
Viburnum Opulus ◽  
Tetrazolium Test

Abstract Mature specimens of Viburnum opulus and cultivars ‘Leonard's Dwarf’ and ‘Roseum’ were assessed over 2 years for flower and seed production, seed germination, and seed viability as determined by a tetrazolium test to understand their invasive potential. ‘Aureum’, ‘Compactum’, ‘Losely's Compact’, ‘Nanum’, and ‘Xanthocarpum’ were also tested for germination and viability of seeds. Cultivars differed in flower and seed production, seed germination, and seed viability. ‘Roseum’ prolifically produced highly viable seed that germinated at moderate rates under greenhouse conditions (8,354, 100%, and 73%, respectively). Viburnum opulus and ‘Leonard's Dwarf’ produced fewer viable seed which showed moderate to low germination rates (609, 100%, and 53%; 712, 100%, and 5%, respectively). ‘Aureum’ and ‘Xanthocarpum’ seeds germinated at moderate rates (55 and 25%, respectively) and were highly viable (100%). ‘Compactum’, ‘Losely's Compact’, and ‘Nanum’ germinated at low rates or failed to germinate (0, 0, and 5%, respectively), yet seeds were moderately viable (37, 65, and 55%, respectively). Seeds of all cultivars germinated at low rates or failed to germinate at both outdoor sites (0 to 5%) which suggests these plants may be weakly invasive. Short-term studies on biological traits such as these provide only limited information to assess the invasive potential of cultivars.

Seed production and dispersal patterns in populations of Liriodendrontulipifera at the northern edge of its range in southern Ontario, Canada

1990 ◽  
Vol 20 (9) ◽  
pp. 1461-1470 ◽  
Author(s):  
Kevin Kavanagh ◽  
T. J. Carleton
Keyword(s):  
Seed Production ◽  
Seed Viability ◽  
Stand Density ◽  
High Density ◽  
Dispersal Patterns ◽  
Individual Tree ◽  
Large Trees ◽  
Seed Trap ◽  
Northern Edge ◽  
Stand Conditions

Seed production, viability, and dispersal patterns were examined for populations of Liriodendrontulipifera L. (tuliptree) at the northern edge of its range in Ontario, Canada, to determine whether these factors could account for its locally limited distribution. Seed production was measured by estimating the number of samara cones present in the canopy, and samaras collected in traps were dissected to determine potential seed viability under different stand conditions. Seed-trap collections were used to delineate seedfall patterns around individual tree stems and within high-density stands. Results indicate that seed production in Ontario begins when trees reach approximately 25 cm diameter at breast height and increases with maturity. Large trees often produce more than 2000 cones in good years, a level similar to more southern populations. The proportion of samaras containing filled seed increases with stand density, ranging from approximately 8–10% for isolated trees to over 20% for old-growth, high-density stands. Although low, these values are comparable to those reported elsewhere in the species' range. Seedfall patterns followed a leptokurtic distribution about individual stems. Life-history attributes other than seed viability may therefore be the cause of the restricted distribution and low population levels of L. tulipifera in Ontario.

Neotyphodium endophytes in tall fescue seed: viability after seed production and prolonged cold storage

2008 ◽  
Vol 36 (3) ◽  
pp. 710-720 ◽  
Author(s):  
S.L. Clement ◽  
R.C. Martin ◽  
J.E. Dombrowski ◽  
L.R. Elberson ◽  
M. Kynaston ◽  
...  
Keyword(s):  
Seed Production ◽  
Cold Storage ◽  
Tall Fescue ◽  
Seed Viability

Seed Production of Wiregrass in Central Florida Following Growing-Season Prescribed Burns

1994 ◽  
Vol 4 (2) ◽  
pp. 123 ◽  
Author(s):  
KW Outcalt
Keyword(s):  
Seed Production ◽  
Seed Viability ◽  
Pinus Palustris ◽  
Growing Season ◽  
Production Potential ◽  
Prescribed Burns ◽  
Central Florida ◽  
Major Species ◽  
Burned Site ◽  
June July

Wiregrass (Aristida stricta Michx.) is a major species in the long leaf pine (Pinus palustris Mill.) sandhills areas of central Florida, providing a major portion of the fuel for the recurring ground fires necessary to maintain the community. Growing season burning promotes flower and seed production. The objective of this study was to assess the seed production potential of wiregrass following prescribed burns from May through August. Four longleaf wiregrass sites were prescribed burned, one each in May, June, July, and August. Information on bunch size, bunch density, seed stalk density, seed density, and seed germination were collected. The four sites differed significantly in the density of wiregrass bunches, average bunch size, wiregrass cover and seed viability. The density of seed stalks was fairly consistent across sites. Viable seed production was lowest on the June burned site and highest on the July burned site. The study shows good quantities of seed are comparatively easy to produce with growing season bums.

scholarly journals Prediction Equations for Black Spruce Seed Production and Dispersal in Northern Ontario

1982 ◽  
Vol 58 (2) ◽  
pp. 96-99 ◽  
Author(s):  
B. Payandeh ◽  
V. F. Haavisto
Keyword(s):  
Seed Production ◽  
Nonlinear Regression ◽  
Picea Mariana ◽  
Black Spruce ◽  
Seed Viability ◽  
Original Data ◽  
Regression Equations ◽  
Northern Ontario ◽  
Solution Of Equations ◽  
Number Of Seeds

Nonlinear regression equations were developed to describe seed production and dispersal in black spruce (Picea mariana [Mill.]B.S.P.)in northern Ontario. Solution of the equations can provide useful information beyond the range of the original data, because of the flexibility of the models used. For example, solution of equations 1-3 indicates that cones from intermediate crown class trees initially have about twice as many seeds as those of either the dominant or codominant trees, but disperse their seeds at a much faster rate. Average number of seeds per cone for all three crown classes is about 7 after 10 years. Older cones of the intermediate crown class trees have fewest seeds per cone. Solution of equation 4 indicates that average seed viability is about 53% and decreases only slightly during the first three years. It then decreases very rapidly up to 12 years to about 5%. Similarly, equations 6 and 7 may be solved to determine an optimum strip-cut width for sufficient seedfall across the strip to produce satisfactory regeneration.

scholarly journals Effect of botanicals and insecticides seed treatment and containers on seed longevity of black gram under natural ageing conditions

2015 ◽  
Vol 7 (1) ◽  
pp. 328-334 ◽  
Author(s):  
N. Amruta ◽  
G. Sarika ◽  
Umesha Umesha ◽  
J. B. Maruthi ◽  
G. V. Basavaraju
Keyword(s):  
Seed Production ◽  
Seed Treatment ◽  
Seed Quality ◽  
Seed Viability ◽  
Dry Weight ◽  
Management Approach ◽  
Black Gram ◽  
Ambient Conditions ◽  
Emamectin Benzoate ◽  
Production Programme

Good storage is the basic requirement in seed production programme as maintenance of high seed viability and vigour from harvest to planting is of utmost importance in a seed production programme. Therefore, inexpensive, simple and practicable technology to prolong the shelf life of seeds under ambient condition is immensely needed. Hence, an experiment was carried out to study the effect of seed treatment with neem oil, nimbicidin, emamectin benzoate 5 SG, deltamethrin 2.8 EC, novuluron EC on black gram seed quality under ambient conditions. The seeds without any seed treatment were included as control. The treated and untreated seeds were stored in cloth bag and polylined cloth bag. The results revealed that, botanicals and emamectin benzoate seed treatments were significantly superior in controlling the storage insect and maintaining higher seed quality up to 10 months of storage when compared to control. Among the chemicals, the emamectin benzoate 5 SG @ 40 mg kg-1 of seed found better by recording significantly higher germination percentage (80.28), vigour index I (2124) and dry weight of seedlings (43.14 mg) and lower electrical conductivity (0.939 dSm-1) and seed damage (0.00 %) compared to control (78.78%, 2012, 38.90 mg, 0.942 dSm-1, respectively) at the end of 10th month of storage. The emamectin benzoate 5 SG and nimbicidintreated seeds stored in polylined cloth bags were considered as effective seed storage management approach in blackgram.

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