Promotion of cone and seed production in grafted and seedling Douglas-fir seed orchards by application of gibberellin A4/7 mixture

1980 ◽  
Vol 10 (4) ◽  
pp. 464-469 ◽  
Author(s):  
Stephen D. Ross ◽  
Richard P. Pharis ◽  
J. C. Heaman
Keyword(s):  
Seed Production ◽  
Seed Set ◽  
Douglas Fir ◽  
Adjunct Treatment ◽  
Seed Cone ◽  
Marked Enhancement ◽  
Napthaleneacetic Acid ◽  
Low Levels ◽  
Effective Adjunct ◽  
Filled Seeds

Both 4-year-old grafts and 6-year-old seedlings of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) were induced to flower, and the production of seed cones and filled seeds was significantly enhanced by branch applications of gibberellin A4/7 (GA4/7) mixture.For 6-year-old seedlings, when pooled over all levels of the auxin, napthaleneacetic acid (NAA), seed cone bud differentiation, and number of filled seeds per treatment branch tended to be enhanced by GA3, GA5, and GA9, relative to controls. A more marked enhancement (although still not significant) in number of filled seeds per treatment branch was noted for GA3, GA5, and GA9 when applied in combination with GA4/7, relative to GA4/7 alone. The combination of GA9 + GA4/7 significantly increased the number of seed cone buds differentiated, relative to GA4/7 alone. Low levels of NAA, pooled over all GA treatments, significantly increased the number of seed cones per branch at maturity, and tended to increase both the number of seed cone buds differentiated and filled seeds per branch.Girdling, an effective adjunct treatment for promoting flowering, reduced filled seeds per cone for grafts, but had no effect on seedlings. Neither cone abortion nor seed set was affected by the hormone treatments, although there was a tendency in the seedlings for NAA to reduce cone abortion and increase filled seeds per cone. Seed from GA-induced cones germinated equally as well as that from controls. For grafts, GA treatments resulted in a 500% increase in per-branch yield of filled seeds; for seedlings, increases of 250 to 600% were noted.

Seed cone traits and insect damage in Tsuga canadensis (Pinaceae)

2004 ◽  
Vol 34 (1) ◽  
pp. 261-265 ◽  
Author(s):  
Jean J Turgeon ◽  
Chuck Jones ◽  
M Isabel Bellocq
Keyword(s):  
Seed Production ◽  
Tsuga Canadensis ◽  
Insect Damage ◽  
First Report ◽  
Seed Cone ◽  
Length Width ◽  
Maximum Proportion ◽  
Sterile Seed ◽  
The Impact ◽  
Filled Seeds

We measured seed cones of Tsuga canadensis (L.) Carrière, assessed seed potential (number of fertile scales × 2) and seed efficiency (number of filled seeds/seed potential), and estimated the impact of Eupithecia mutata Pearsall (Lepidoptera: Geometridae) and Megastigmus hoffmeyeri Walley (Hymenoptera: Torymidae) on seed production. Mean length, width, and volume of healthy cones varied little among sites from Ontario. Cones had about 28 scales; 13 were sterile. Seed potential and seed efficiency differed among sites, ranging from 25 to 31 ovules and 24% to 72%, respectively. The number of scales (both sterile and fertile) increased with cone volume, but the proportion of fertile scales was independent of cone size. The maximum proportion of cones infested by E. mutata was 21%. On average, each larva destroyed >90% of the filled seeds from each cone, thus from a practical perspective, the proportion of T. canadensis seeds destroyed per site was equivalent to the proportion of seed cones infested. The proportion of cones infested by M. hoffmeyeri ranged from 9% to 40%, but the proportion of seeds destroyed per site (range: 1.1%–6.1%) was much lower than that of E. mutata. The maximum number of M. hoffmeyeri-infested seeds per cone was seven. To our knowledge, this is the first report documenting cone traits of T. canadensis and the impact of E. mutata and M. hoffmeyeri.

The pollination mechanism and the optimal time of pollination in Douglas-fir (Pseudotsugamenziesii)

1981 ◽  
Vol 11 (1) ◽  
pp. 36-50 ◽  
Author(s):  
John N. Owens ◽  
Sheila J. Simpson ◽  
Marje Molder
Keyword(s):  
Electron Microscopy ◽  
Seed Set ◽  
Pollen Grains ◽  
Douglas Fir ◽  
Optimal Time ◽  
Pollination Mechanism ◽  
Seed Cone ◽  
Poor Seed ◽  
Micropylar Canal ◽  
Scanning Electron

The development of the pollination mechanism and the engulfment of pollen by the stigmatic tip is described for Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) based on scanning electron microscopy. This information is used to determine and explain the optimal time of pollination and amount of pollen needed for maximum seed set. After dormancy the integument tip of the ovule developed into an unequally two-lobed stigmatic tip covered with long unicellular hairs. Most ovules had fully developed stigmatic tips when the seed cone emerged from the bud scales in early April. The conelets remained open and the stigmatic tip was most receptive for at least 4 days. Pollen freely sifted down between the bracts and ovuliferous scales and adhered to the stigmatic hairs. Six days after the conelets became receptive, stigmatic hairs around the micropyle began to collapse and were ungulfed with the entangled pollen into the micropyle. Also, ovuliferous scales began to thicken, restricting movement of pollen to the stigmatic tips. By 8–10 days after conelets became receptive, the stigmatic tips were completely engulfed, the ovuliferous scales had thickened enough to close the conelet, and the conelet had begun to bend down.Maximum seed set occurred when (1) cones were pollinated within 4 days after seed-cone buds had emerged half of the way out of their bud scales; (2) a minimum of 0.2 g of pollen was used per pollination bag; (3) a minimum of 11 pollen grains adhered to each stigmatic tip; and (4) at least 3 pollen grains were taken into each micropylar canal. The engulfing process occurred at the same rate and in the same manner regardless of whether living or heat-killed pollen was present or absent on the stigmatic surface. Poor seed set as it related to the pollination mechanism is discussed.

Effect of growth regulators, girdling, and mulching on flowering of young European and Japanese larches under field conditions

1982 ◽  
Vol 12 (2) ◽  
pp. 270-279 ◽  
Author(s):  
Marc Bonnet-Masimbert
Keyword(s):  
Surfactant Solution ◽  
Hormone Treatment ◽  
Naphthalene Acetic Acid ◽  
Plastic Film ◽  
Old Field ◽  
Male And Female ◽  
Adjunct Treatment ◽  
Seed Cone ◽  
Female Flowering ◽  
Effective Adjunct

Two experiments were undertaken in 1977 and 1979 to promote flowering of 5- and 7-ycar-old field-grown seedlings of Larixleptolepis Gord. and L. decidua Mill. A gibbcrellin A4/7 mixture (GA4/7) was applied alone or in combination with GA3 and naphthalene acetic acid (NAA) to both girdled and nongirdled trees or branches by two methods, perfusion into the xylem and spraying with an aqueous cationic surfactant solution. Perfusion was most effective, especially on girdled branches, although spraying was reasonably effective for male flowering in L. decidua. Only GA4/7 alone significantly increased flowering. Male flowering was doubled and female flowering increased eightfold by GA4/7 in the best treatments, over all application dates. Generally, male flowering doubled and female flowering increased eightfold by GA4/7. Even more flowering was obtained at optimal application dates. May and June applications were best, especially for treatments associated with girdling. However, some flowering occurred with applications as late as August and September. More strobili of both sexes develop in the upper crown. However GA4/7 treatment induced seed cone buds to appear in the lower crown, an abnormal location. An unusual effect occurred in that a positive flowering response of the 1977 experiment occurred only in 1979, whereas the 1979 experiment yielded enhanced flowering in 1980. Soil mulching with a plastic film, with or without hormone treatment, was a very effective adjunct treatment for both male and female flowering.

Variation in seed set and proportions of outcrossed progeny with clones, crown position, and top pruning in a Douglas-fir seed orchard

1986 ◽  
Vol 16 (3) ◽  
pp. 502-507 ◽  
Author(s):  
S. K. Omi ◽  
W. T. Adams
Keyword(s):  
Maximum Likelihood ◽  
Seed Set ◽  
Seed Orchard ◽  
Douglas Fir ◽  
Crown Position ◽  
Maximum Likelihood Procedure ◽  
Clonal Variability ◽  
Allozyme Loci ◽  
Filled Seeds

The effects of clonal variability, crown position of cones, and top pruning on the proportions of viable outcrossed progeny [Formula: see text] and filled seeds (PF) were investigated in a 20-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seed orchard. Estimates of [Formula: see text] were derived by means of a maximum likelihood procedure from data from 10 allozyme loci. Values for [Formula: see text] and PF were significantly heterogeneous (P < 0.05) among six selected clones for all pruning treatment x clone combinations. On the average, estimated values for [Formula: see text] and [Formula: see text] were greater in seeds collected from the upper crown [Formula: see text] than from the lower crown [Formula: see text]. Combined over crown positions, pruning appeared to have little effect on [Formula: see text], although the proportion of filled seeds was slightly lower in pruned ramets [Formula: see text] than in unpruned ramets [Formula: see text]. The overall frequency of viable selfs [Formula: see text] in the progeny of the six clones was 0.08.

scholarly journals Lower-Dose, Intravenous Chlorothiazide Is an Effective Adjunct Diuretic to Furosemide Following Pediatric Cardiac Surgery

2020 ◽  
Vol 25 (1) ◽  
pp. 31-38
Author(s):  
Ryan J. Carpenter ◽  
Shaghig Kouyoumjian ◽  
David Y. Moromisato ◽  
Phuong Lieu ◽  
Rambod Amirnovin
Keyword(s):  
Fluid Balance ◽  
Urine Output ◽  
Heart Defects ◽  
High Dose ◽  
Total Fluid Intake ◽  
Adjunct Treatment ◽  
Negative Fluid Balance ◽  
Poor Outcomes ◽  
Neonates And Infants ◽  
Effective Adjunct

OBJECTIVES Postoperative fluid overload is ubiquitous in neonates and infants following operative intervention for congenital heart defects; ineffective diuresis is associated with poor outcomes. Diuresis with furosemide is widely used, yet there is often resistance at higher doses. In theory, furosemide resistance may be overcome with chlorothiazide; however, its efficacy is unclear, especially in lower doses and in this population. We hypothesized the addition of lower-dose, intravenous chlorothiazide following surgery in patients on high-dose furosemide would induce meaningful diuresis with minimal side effects. METHODS This was a retrospective, cohort study. Postoperative infants younger than 6 months, receiving high-dose furosemide, and given lower-dose chlorothiazide (1–2 mg/kg every 6–12 hours) were identified. Diuretic doses, urine output, fluid balance, vasoactive-inotropic scores, total fluid intake, and electrolyte levels were recorded. RESULTS There were 73 patients included. The addition of lower-dose chlorothiazide was associated with a significant increase in urine output (3.8 ± 0.18 vs 5.6 ± 0.27 mL/kg/hr, p &lt; 0.001), more negative fluid balance (16.1 ± 4.2 vs −25.0 ± 6.3 mL/kg/day, p &lt; 0.001), and marginal changes in electrolytes. Multivariate analysis was performed, demonstrating that increased urine output and more negative fluid balance were independently associated with addition of chlorothiazide. Subgroup analysis of 21 patients without a change in furosemide dose demonstrated the addition of chlorothiazide significantly increased urine output (p = 0.03) and reduced fluid balance (p &lt; 0.01), further validating the adjunct effects of chlorothiazide. CONCLUSION Lower-dose, intravenous chlorothiazide is an effective adjunct treatment in postoperative neonates and infants younger than 6 months following cardiothoracic surgery.

Cost of reproduction in Douglas-fir

1992 ◽  
Vol 70 (7) ◽  
pp. 1429-1432 ◽  
Author(s):  
Yousry A. El-Kassaby ◽  
Hugh J. Barclay
Keyword(s):  
Pseudotsuga Menziesii ◽  
Annual Ring ◽  
Ring Width ◽  
Energy Allocation ◽  
Douglas Fir ◽  
Environmental Correlations ◽  
Annual Ring Width ◽  
Trade Off ◽  
Cone Production ◽  
Seed Cone

The balance between allocating energy resources to reproduction or growth has considerable theoretical interest. Conflicting ecological requirements and evolutionary pressures often necessitate a trade-off in energy allocation. We obtained measurements on seed-cone production and annual ring width of 365 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees from 29 open-pollinated families for 8 years. Phenotypic, genetic, and environmental correlations were computed for seed-cone production and ring width for each year. Five of the eight environmental correlations were negative (range −0.077 to −0.305), reflecting the reality of the trade-off in physiological terms. Six of the eight genetic correlations were negative (range −0.199 to −0.776), indicating that a trade-off exists at the genetic level between energy allocation to reproduction and to somatic growth. These findings agree with the current theory of life-history evolution. Key words: Pseudotsuga menziesii, cone production, annual ring width, genetic correlation.

Seasonal changes in seed reduction in lodgepole pine cones caused by feeding of Leptoglossus occidentalis (Hemiptera: Coreidae)

2006 ◽  
Vol 138 (6) ◽  
pp. 888-896 ◽  
Author(s):  
Ward B. Strong
Keyword(s):  
Adult Female ◽  
Pinus Contorta ◽  
Seed Set ◽  
Lodgepole Pine ◽  
Seed Orchard ◽  
Damage Potential ◽  
Leptoglossus Occidentalis ◽  
Pine Cones ◽  
Insect Exclusion ◽  
Filled Seeds

AbstractManagement of Leptoglossus occidentalis Heidemann in lodgepole pine (Pinus contorta var. latifolia Engelm.) seed orchards of British Columbia, Canada, would be improved with knowledge of its damage potential at different times of the growing season. Mesh insect-exclusion bags were placed over cones, and adults or nymphs of L. occidentalis were enclosed in different bags for 9 periods of 10 to 38 days between 6 May and 17 September 2004. Feeding by adult females between 6 May and 28 May reduced total extractable seeds, a result of ovule damage before fertilization. Reduction in the number of filled seeds per cone was highest between 6 May and 29 June, with each adult female reducing yield by approximately 1.7 seeds per day. Between 29 June and 10 August, each adult female reduced the number of filled seeds per cone (seed set) by 1.0 to 1.25 per day. Seed set reduction declined to approximately 0.25 filled seeds per adult female per day after 10 August. Third to fifth instars caused seed set reduction between 0.6 and 1.2 filled seeds per cone per nymph feeding day from 29 June to 10 August. Utilizing these findings would improve management of L. occidentalis in a commercial seed orchard setting.

Effect of companion perennial grasses and lucerne on seed yield and regeneration of subterranean clover in two wheatbelt environments

2001 ◽  
Vol 52 (10) ◽  
pp. 973 ◽  
Author(s):  
B. S. Dear ◽  
J. M. Virgona ◽  
G. A. Sandral ◽  
A. D. Swan ◽  
B. A. Orchard
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Seed Bank ◽  
Seed Set ◽  
Subterranean Clover ◽  
Seedling Regeneration ◽  
Early Autumn ◽  
Background Population ◽  
Seed Reserves ◽  
Clover Seed

Seed production of subterranean clover (Trifolium subterraneum L.) in mixtures with lovegrass (Eragrostis curvula (Schrader) Nees cv. Consol), cocksfoot (Dactylis glomerata L. cv. Currie), phalaris (Phalaris aquatica L. cv. Sirolan), danthonia (Austrodanthonia richardsonii (Cashm.) H.P. Linder, cv. Taranna), and lucerne (Medicago sativa L. cv. Aquarius) was compared with pure and degraded (invaded by annual volunteers) annual subterranean clover pasture at 2 sites (Junee and Kamarah) in the southern wheatbelt of New South Wales. Seed yields, clover seedlings in winter, and the change in the proportion of 3 subterranean clover cultivars (Dalkeith, Seaton Park, Goulburn) when grown with and without perennials were assessed. The effect of thinning the perennials to 10 plants/m2 on clover seed set was examined at the drier site. Seed production of subterranean clover in the mixtures was depressed by up to 50% compared with the pure and degraded annual swards. Initial clover seed poduction in the mixtures was at least 60 kg/ha even in the drought year at the wetter site (Junee), and >85 kg/ha at Kamarah, the drier site (seedling establishment at Kamarah failed in the drought year). Clover seed reserves in the following 2 years progressively increased to >300 kg/ha in the perennial swards at Junee but were <100 kg/ha by the end of the third year at Kamarah. In comparison, seed reserves in the pure clover and degraded annual swards were >650 kg/ha at Junee and >350 kg/ha at Kamarah. Reducing perennial density to 10 plants/m2 at the drier site increased clover seed yield about 3-fold in the first year compared with unthinned perennial swards. The increased seed yield was due to increased numbers of burrs set and increased seeds per burr and, in all perennial pasture treatments except lucerne, increased seed size. Clover seedling regeneration in 3rd and 4th year after sowing was substantially lower in the perennial-based mixtures than annual plots, with a significant (P < 0.05) positive correlation at both sites between clover seedling regeneration and seed bank size (1996, r2 = 0.46–0.64; 1997, r2 = 0.64–0.85). Following false breaks in early autumn, clover seedling populations were substantially higher in the pure and degraded clover treatments than in most perennial treatments. The proportion of the 3 cultivars present in the seed bank at the end of the pasture phase differed between sites but the sward type only influenced the proportion at the drier site. At the medium rainfall site, the later maturing cultivar Goulburn constituted 27–54% of the seed bank and the early flowering Dalkeith 25–46%, with unsown cultivars being insignificant ( <1%). At the low rainfall site, Dalkeith was the major component (33–52%) of the seed bank but the background population of unsown cultivars constituted 11–48%, the lowest proportion being in swards without a perennial component. The proportion of Goulburn was highest (23%) in the pure sward and lowest (10%) in lucerne and phalaris. It was concluded that subterranean clover could form relatively stable mixtures with perennials in medium rainfall environments, with clover populations increasing with time. In lower rainfall environments, clover seedling populations in perennial swards may be low due to reduced seed set and decreased seedling survival following early autumn rains. In these environments earlier maturing, hard-seeded cultivars are more likely to persist in mixtures and there is more potential for unsown cultivars to constitute a greater proportion of the sward. Decreasing perennial density offers scope for improving clover seed set and survival in these environments.

The effects of frequency and extent of defoliation, summer irrigation, and fertilizer on the production and survival of the grass Danthonia caespitosa Gaud

1976 ◽  
Vol 27 (6) ◽  
pp. 755 ◽  
Author(s):  
KC Hodgkinson
Keyword(s):  
Seed Production ◽  
Death Rate ◽  
Field Experiments ◽  
Seed Set ◽  
Floral Induction ◽  
Early Winter ◽  
Phosphorus Fertilizer ◽  
Nitrogen And Phosphorus ◽  
Plant Survival ◽  
Growth And Survival

The effects of extent and frequency of defoliation on the growth and survival of Danthonia caespitosa were measured in a series of field experiments. Additional treatments, of summer irrigation and application of nitrogen and phosphorus fertilizer, were included in some of the experiments to assess how they modified the effects of defoliation. During the summer, complete defoliation increased the shoot yield of plants which had not been irrigated, but yield was decreased in the irrigated treatments. Frequent, partial defoliation increased yields of irrigated plants but decreased yields of plants not irrigated. Depression of yields was caused by both tiller death and reduced regrowth of individual tillers. In an experiment lasting 2 years, plants were completely defoliated monthly, bimonthly or tri-monthly or left intact, and shoot yields, tillering characteristics and plant survival under the treatments were compared. Monthly defoliation depressed yields and rate of tillering and accelerated the death rate of plants, particularly during the summer and autumn periods. Plants also died when cut bimonthly but the rate was slower. Plants irrigated during the first summer generally died at a faster rate than plants not irrigated. Tillering was more rapid during the autumn and early winter months. Midwinter application of fertilizer to plants cut bimonthly greatly stimulated shoot yields and seed production in the spring but not in the following year. Examination of tiller apices showed that floral induction took place prior to the beginning of July. Many apices were elevated above the 'grazing level' by early September, and flowering and seed set occurred in October.

Increased seed production of subterranean clover pastures in response to fertilizers supplying calcium

1974 ◽  
Vol 14 (71) ◽  
pp. 749 ◽  
Author(s):  
PG Ozanne ◽  
KMW Howes
Keyword(s):  
Seed Production ◽  
Calcium Concentration ◽  
Field Experiments ◽  
Seed Set ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Unit Weight ◽  
Gypsum Plaster ◽  
Total Seed ◽  
Seed Yields

The effects of four common fertilizers containing calcium on seed production in subterranean clover (Trifolium subterraneum) were measured at six locations over five years in a total of fifteen field experiments. Calcium as a sulphate, carbonate or phosphate salt was applied to subterranean clover pastures either at the start of the growing season (autumn) or at flowering (spring). Gypsum, plaster of Paris, or lime gave large increases in seed yield per unit area and also per unit weight of tops. Spring applications of superphosphate increased seed yields in only two out of four experiments. Gypsum applied in spring at 200-500 kg ha-1 was as effective as 2,000 kg ha-1 of lime applied in autumn. Applications of lime in spring were much less effective. Increased seed yields were due to increases in burr yield, seed number per burr, and mean weight per seed. They were usually accompanied by increases in calcium concentration in the seed. Responses in seed production to calcium applications were obtained in all three sub-species of Trifolium subterraneum. In two experiments, newly sown on a soil type on which subterranean clover regeneration and persistence is commonly very poor, applied calcium doubled or quadrupled seed set. In 13 experiments using soils on which subterranean clover had persisted as the major component of the pasture for several years, calcium in the year of application increased the total seed bank by 6 to 31 per cent, and the current seed set by a greater amount.

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