scholarly journals Uncoupled Evolution of Male and Female Cone Sizes in an Ancient Conifer Lineage

2019 ◽  
Vol 180 (1) ◽  
pp. 72-80 ◽  
Author(s):  
Gabriela Gleiser ◽  
Karina L. Speziale ◽  
Sergio A. Lambertucci ◽  
Fernando Hiraldo ◽  
José L. Tella ◽  
...  
Keyword(s):  
Female Cone ◽  
Male And Female

scholarly journals Studies on the Pollination Characteristics and Pollination Level of Chinese fir Seed Orchard

2004 ◽  
Vol 53 (1-6) ◽  
pp. 7-11 ◽  
Author(s):  
Z. Zhuowen
Keyword(s):  
Accumulation Rate ◽  
Pollen Grains ◽  
Seed Orchard ◽  
Distribution Patterns ◽  
Chinese Fir ◽  
Female Cone ◽  
Bottom Part ◽  
Male And Female ◽  
Seed Orchards ◽  
Male Cone

Abstract Data from three seed orchards (Chongyang, Zhangle and Laoshan) and Lintian forest were used to study pollination characteristics, pollination level, pollen and ovule production in Chinese fir. The results show that male and female cones have their own distribution patterns within crowns. Male cones are located in the middle to top and female cones the middle to bottom part of the crown. Because of lower density of trees in seed orchard than that in a stand, female cones are distributed over the entire crown in seed orchard trees. Chinese fir male and female cones appear to be very well adapted for wind as the pollination mechanism. There is no difference in the number of pollen grains produced by one pollen sac among trees in the same clone, but there are differences between clones. There are differences between both clones and years in female cone number, male cone number and their ratio. The pollen accumulation rate during pollination should be 3 to 5 pollen grains/mm2 to ensure fertilization. The Chinese fir seed orchards in this study produced too much pollen and could be improved by stimulation of more female flowers in order to produce more seeds.

Nitrapyrin (2-chloro-6-(trichloromethyl)-pyridine), a nitrification inhibitor, may replace fertilizers for promoting cone bud production in southern pine seed orchards

1984 ◽  
Vol 14 (2) ◽  
pp. 206-208
Author(s):  
Robert C. Hare
Keyword(s):  
Soil Nitrogen ◽  
Nitrogen Fertilization ◽  
Nitrification Inhibitor ◽  
Southern Pine ◽  
Female Cone ◽  
Nitrate Sources ◽  
Male And Female ◽  
Seed Orchards ◽  
Soil Application ◽  
Cone Production

Male and female cone bud and cone production in loblolly (Pinustaeda L.) and slash (Pinuselliottiielliottii Engelm.) pine was significantly stimulated by June soil application of nitrapyrin (2-chloro-6-(trichloromethyl)-pyridine), a specific toxin for nitrifying and denitrifying bacteria. Nitrapyrin presumably acts by conserving ambient soil nitrogen since only 1.5–2 g promoted cone buds as effectively as 150 g of elemental nitrogen from either ammonium or nitrate sources. Nitrapyrin may serve as a less costly substitute for nitrogen fertilization in seed orchards.

scholarly journals Reproductive Ecology of Male and Female Strobili and Mating System in Two Different Populations ofPinus roxburghii

2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Chandra Mohan Sharma ◽  
Vinod Prasad Khanduri ◽  
Sunil Kumar Ghildiyal
Keyword(s):  
Mating System ◽  
Natural Populations ◽  
Production Capacity ◽  
Pollen Grains ◽  
Seed Orchard ◽  
Reproductive Period ◽  
Female Cone ◽  
Lower Altitude ◽  
Female Ratio ◽  
Male And Female

We studied several flowering traits, namely, male-female cone phenology, male-female cone production per tree, mating system, sex ratio, air-borne pollen grains and pollen migration, over four successive years in two different natural populations ofP. roxburghiifrom Garhwal Himalaya, India. Assessment of each trait mentioned except pollen dispersion was done by selecting five representative trees randomly in each population. The pollen migration was studied on naturally isolated source trees. The pollen trapping was done in all directions up to 2.5 km. The average reproductive period inP. roxburghiiwas 36 days with 3–5 days protandry. There were significant year and population effects for male and female cone output and pollen grains production per tree. In mass production year (1999), an average production of pollen cone per tree was estimated as42.44±8.32×103at lower altitude and28.1±0.89×103at higher altitude. The controlled pollination results in high level of outcrossing with 90% seed setting. We conclude that the high male-female ratio and tremendous pollen production capacity inP. roxburghiiindicate high male competition among trees within populations. The isolation strip of 600 m is considered minimal for the management of seed orchard.

scholarly journals Hormonal balance in apical meristems of Scots pine shoots as a very early symptom of flower sex differentiation

2015 ◽  
Vol 47 (1–2) ◽  
pp. 107-114
Author(s):  
J. Kopcewicz ◽  
Z. Zatorska ◽  
H. Kulikowska ◽  
T. Szcześniak
Keyword(s):  
Scots Pine ◽  
Sex Differentiation ◽  
Female Cone ◽  
Early Symptom ◽  
Male And Female ◽  
Apical Meristems ◽  
Hormonal Balance ◽  
Long Time

The investigations were conducted on the embryonic shoots which were taken at the stage just before the start of the elongation of the last year formed embryonic shoot; it means long time before male and female cone primordia initiation. The results point out to the existence of distinctive balance of auxins to gibberellins in apical meristems oi potentially female and male shoots for about a month before the initiation of new embryonic shoots. These results confirm our previous suggestions that femaleness and maleness in Scots pine is correlated with a high amount of auxins and gibberellins, respectively.

scholarly journals Bud Initiation, Microsporogenesis, Megasporogenesis, and Cone Development in Platycladus orientalis

HortScience ◽  
2021 ◽  
Vol 56 (1) ◽  
pp. 85-93
Author(s):  
Ting Liao ◽  
Guobin Liu ◽  
Liqin Guo ◽  
Ye Wang ◽  
Yanwu Yao ◽  
...  
Keyword(s):  
Seed Development ◽  
Treatment Time ◽  
Male Gametophyte ◽  
Northern China ◽  
Female Cone ◽  
Male And Female ◽  
Platycladus Orientalis ◽  
Artificial Induction ◽  
Mother Cells ◽  
Bud Initiation

As a native tree species with a strong adaptability, Platycladus orientalis is a species of choice for afforestation and landscaping in northern China. However, it develops mostly male cones and few female cones. In addition, its reproductive characteristics are not yet clear, which limits further breeding work. To systematically clarify the reproductive biology characteristic and fertilization mechanism of P. orientalis, the present study comprehensively investigated the process of micro and macro-sporogenesis in male and female cones from bud initiation to fertilization, and seed development. The specific time in each developmental stage, including bud initiation, microsporogenesis, megasporogenesis, and cone and seed development, was determined, and the abortive phenomenon during development was discovered in both male and female cones. In addition, this research showed that the microspore mother cells were dormant in winter at meiosis stage, and the male gametophyte started to develop when dormancy ended. The tapetum developed normally and belonged to the secretory type. The optimal treatment time for male and female cones transformation by artificial induction was from late June to mid-July. This finding provided a theoretical basis for hybridization, breeding, improvement of seed yield and quality, and artificial induction of male and female cone transformation in P. orientalis.

scholarly journals Analysis of Phytohormone Profiles during Male and Female Cone Initiation and Early Differentiation in Long-shoot Buds of Lodgepole Pine

2012 ◽  
Vol 31 (4) ◽  
pp. 478-489 ◽  
Author(s):  
Lisheng Kong ◽  
Patrick von Aderkas ◽  
Irina Zaharia ◽  
Suzanne R. Abrams ◽  
Tim Lee ◽  
...  
Keyword(s):  
Lodgepole Pine ◽  
Female Cone ◽  
Male And Female ◽  
Shoot Buds ◽  
Early Differentiation

scholarly journals Tertiary Araucariaceae From South-Eastern Australia, With Notes on Living Species

1951 ◽  
Vol 4 (4) ◽  
pp. 415 ◽  
Author(s):  
IsabeIC Cookson ◽  
Suzanne L Duigan
Keyword(s):  
Brown Coal ◽  
Female Cone ◽  
Male And Female ◽  
South Eastern ◽  
Eastern Australia ◽  
Living Species ◽  
Male Cones ◽  
South Eastern Australia

The foliage shoots, male cones, and female cone-scales of a new Tertiary species of Araucaria, section Eutacta, from the brown coal at Yallourn, Victoria, have been described; leaves and male and female cones possessing the general features that characterize species of Agathis have been identified. Leaves of a second species of Agathis have been distinguished in a bed associated with the brown coal at Bacchus Marsh, near Melbourne, Vic.

The Clinical, Roentgenological and Morphological Effects of an Acute Exposure of Phosgene on the Lungs of Dogs

1971 ◽  
Vol 29 ◽  
pp. 236-237
Author(s):  
R. F. Bils ◽  
W. F. Diller ◽  
F. Huth
Keyword(s):  
Latent Period ◽  
Chemical Industry ◽  
Toxic Substance ◽  
Lung Edema ◽  
X Rays ◽  
Beagle Dogs ◽  
Male And Female ◽  
Morphological Alterations ◽  
Before And After ◽  
Electron Microscopes

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.

Ultrastructural investigation of spontaneous pituitary gonadotroph cell adenomas in aging Sprague-Dawley rats

1983 ◽  
Vol 41 ◽  
pp. 702-703
Author(s):  
D. J. McComb ◽  
J. Beri ◽  
F. Zak ◽  
K. Kovacs
Keyword(s):  
Electron Microscopy ◽  
Animal Model ◽  
Epoxy Resin ◽  
Immunoelectron Microscopy ◽  
Tumor Type ◽  
Gonadal Function ◽  
Sprague Dawley ◽  
Male And Female ◽  
Reticulin Fibers ◽  
Sprague Dawley Rats

Gonadotroph cell adenomas of the pituitary are infrequent in human patients and are not invariably associated with altered gonadal function. To date, no animal model of this tumor type exists. Herein, we describe spontaneous gonadotroph cell adenomas in old male and female Sprague-Dawley rats by histology, immunocytology and electron microscopy.The material consisted of the pituitaries of 27 male and 38 female Sprague Dawley rats, all 26 months of age or older, removed at routine autopsy. Sections of formal in-fixed, paraffin-embedded tissue were stained with hematoxylin-phloxine-saffron (HPS), the PAS method and the Gordon-Sweet technique for the demonstration of reticulin fibers. For immunostaining, sections were exposed to anti-rat β-LH, anti-ratβ-TSH, anti-rat PRL, anti-rat GH and anti-rat ACTH 1-39. For electron microscopy, tissue was fixed in 2.5% glutaraldehyde, postfixed in 1% OsO4 and embedded in epoxy-resin. Tissue fixed in 10% formalin, embedded in epoxy resin without osmification, was used for immunoelectron microscopy.

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