Developmental and seasonal patterns of mesophyll ultrastructure in Abies balsamea

1975 ◽  
Vol 53 (3) ◽  
pp. 295-304 ◽  
Author(s):  
Jean Fincher Chabot ◽  
Brian F. Chabot
Keyword(s):  
Cell Structure ◽  
Abies Balsamea ◽  
Growing Season ◽  
Synthetic Activity ◽  
Seasonal Patterns ◽  
Winter Dormancy ◽  
Chloroplast Structure ◽  
Starch Grains ◽  
Mesophyll Ultrastructure ◽  
Accumulation Of Lipids

Changes in mesophyll ultrastructure with development and season are described for Abies balsamea. Cells mature sequentially during expansion of the needles. Most cells appear to be fully mature and actively photosynthesizing at the time of budbreak. Tannins appear early and accumulate throughout the growing season. Winter dormancy is marked by an accumulation of lipids throughout the cell, an aggregation of organelles around the nucleus, some loss of chloroplast structure, and a failure of chloroplasts to form starch grains. Reorganization of cell structure and resumption of synthetic activity in the spring occurs about 2 months before budbreak.

Seasonal changes in mesophyll ultrastructure of needles of Norway spruce (Picea abies)

1978 ◽  
Vol 56 (16) ◽  
pp. 1932-1940 ◽  
Author(s):  
Sirkka Soikkeli
Keyword(s):  
Cell Wall ◽  
Picea Abies ◽  
Norway Spruce ◽  
Seasonal Changes ◽  
Lipid Droplets ◽  
Cell Structure ◽  
Weather Conditions ◽  
Growing Season ◽  
Starch Grains ◽  
Mesophyll Ultrastructure

Seasonal changes in the ultrastructure of the mesophyll of needles of Norway spruce are described. During the growing season, the tannin is in the form of a ribbon along the margin of the vacuole or in the form of small, more or less scattered particles. The cytoplasm is dark and its organelles are along the cell wall; only the chloroplasts with large starch grains and the nucleus can be clearly resolved. During and after September, the cytoplasm is very netlike, all of the cytoplasmic organelles clump together, the amount of lipid droplets increases, and ribosomes are clearly visible. The tannin is in the form of rather large granules and it increases over its growing-season amount. The shape of chloroplasts changes. Chloroplasts lose their starch and the stroma becomes sparsely granular and rich in ribosomes. This structure is maintained throughout the winter. During spring activation, the cell structure is reorganized and reassumes the condition typical of the growing season. At this time, the needles have some collapsed cells and cells in which some chloroplasts are not quite intact. The injuries were probably caused by weather conditions (a warm period in March followed by a frost).

scholarly journals Astringency in ʻGiomboʼ persimmon and its relationship with the harvest time

Revista CERES ◽  
2016 ◽  
Vol 63 (5) ◽  
pp. 646-652
Author(s):  
Magda Andréia Tessmer ◽  
Beatriz Appezzato-da-Glória ◽  
Ricardo Alfredo Kluge
Keyword(s):  
Cell Wall ◽  
Exposure Time ◽  
Fruit Quality ◽  
Cell Structure ◽  
Parenchyma Cell ◽  
Growing Season ◽  
Ethanol Exposure ◽  
Harvest Time ◽  
Intercellular Spaces ◽  
Parenchyma Cell Wall

ABSTRACT ʻGiomboʼ is one of most cultivated persimmon cultivars in Brazil. It is a late-harvest cultivar and requires treatment for astringency removal. The aim of this study was to evaluate the efficiency of ethanol and the effect of harvest time on reducing astringency, physicochemical and anatomical characteristics of 'Giombo' persimmon. Two experiments were carried out, one in each growing season, with five treatments corresponding to exposure to 1.70 mL kg-1ethanol for 0, 12, 24, 36 and 48 hours. At the end of the growing season (2011) the fruits achieved the astringency index and levels of soluble tannins suitable for consumption in 24 hours, and at the beginning of the growing season (2012) in 36 hours, indicating that the efficiency of the treatment is related to harvest time and ethanol exposure time. Astringency removal with ethanol affects the cell structure with accumulation of substances inside the cells and in intercellular spaces, resulting in the degradation of the parenchyma cell wall. To avoid such damage and maintain fruit quality, it is recommended the combination of low ethanol doses with less ethanol exposure time.

The performance of hybrids between Mediterranean and Northern European parents of cocksfoot (Dactylis glomerataL.) in a mediterranean type environment

1966 ◽  
Vol 17 (2) ◽  
pp. 105 ◽  
Author(s):  
R Knight
Keyword(s):  
Growing Season ◽  
Special Technique ◽  
Winter Dormancy ◽  
European Origin ◽  
Northern European ◽  
Hybrid Plants ◽  
Growth Variation ◽  
Mediterranean Origin ◽  
The Mediterranean ◽  
Controlled Flowering

Hybrids were produced between seven different parents of Mediterranean origin and two parents of Northern European origin. A special technique of controlled flowering, emasculation, and pollination was used to effect the hybridization. Hybrid plants were grown in undefoliated swards and assessed for cumulative growth, variation in the reproductive phase, tillering, and summer survival. The combining abilities of the parents were estimated for these characters. Hybrids between Mediterranean and Northern European parents were able to respond to summer showers at a time when Mediterranean material was still summer dormant and Northern European material severely affected by dry summer conditions. This out-of-season growth was reflected in the higher yields of the hybrids in the autumn after the main start to the growing season. During midwinter when the Mediterranean material was growing actively the growth of Northern European material ceased and some combinations of Mediterranean and Northern European parents ceased growing. The cessation of growth was attributed to winter dormancy. Plant survival during the summer was 97% for the purely Mediterranean families, 88% for Mediterranean x Northern European families, and 59% for the purely Northern European families. Some of the Mediterranean x Northern European families survived as well as the best Mediterranean families. The potential agricultural value of the Mediterranean x Northern European hybrids and a possible breeding programme with them are discussed.

Effect of season (vegetative flushing) and leaf position on the leaf nutrient composition of Annona spp. hybrid cv. Pink's Mammoth in south-eastern Queensland

1989 ◽  
Vol 29 (4) ◽  
pp. 587 ◽  
Author(s):  
AP George ◽  
RJ Nissen ◽  
ML Carseldine
Keyword(s):  
Leaf Age ◽  
Growing Season ◽  
Mobile Elements ◽  
Nutrient Concentrations ◽  
Seasonal Patterns ◽  
General Decline ◽  
Leaf Sampling ◽  
Sampling Procedures ◽  
Hybrid Cultivar ◽  
Cu And Zn

Seasonal patterns of leaf nutrient concentrations and leaf sampling procedures were established for the Annona spp. hybrid cultivar, Pink's Mammoth in subtropical Queensland (27�S.). One group of nutrients showed a general decline in concentration in the leaves with time (K, 1.448%; P, 0.3-0.15%) while another group showed an overall increase (Ca, 0.4-1.4%; Mg, 0.3-0.54%; B, 24-66 �g/g). Nitrogen leaf levels decreased throughout the growing season (3.5-2.5%), with the pattern of decline strongly influenced by vegetative flushing. Leaf concentrations of Ca, Mg, Mn and B generally increased, and N, P, K, Cu, and Zn decreased with leaf age. Movement of the more mobile elements (i.e. N, P. K, Cu, and Zn) from the older into the younger leaves was more rapid when trees were flushing compared with trees that had completed flushing. Irrespective of the state of flushing, higher concentrations of the less mobile elements Mg, Ca, B and Mn were recorded in the older compared with the younger leaves, indicating that their movement into younger leaves is relatively slow. Our results suggest that the most suitable time to sample leaves is after the completion of vegetative flushing when the concentration of most leaf elements have stabilised. Depending on the element, it may be more appropriate to sample either young or old leaves rather than compromise by sampling only the most recently mature, fully expanded leaf.

Substrate and litterfall effects on conifer seedling survivorship in southern boreal stands of Canada

2003 ◽  
Vol 33 (4) ◽  
pp. 672-681 ◽  
Author(s):  
Marie-Josée Simard ◽  
Yves Bergeron ◽  
Luc Sirois
Keyword(s):  
Populus Tremuloides ◽  
Picea Glauca ◽  
Forest Floor ◽  
Mineral Soil ◽  
Abies Balsamea ◽  
Growing Season ◽  
Winter Survival ◽  
Thuja Occidentalis ◽  
Seedling Survivorship ◽  
Conifer Seedling

Most conifer seeds die as seeds or seedlings within 5 years after dispersal. Understanding what factors keep a few of them alive is essential if natural regeneration is to be maintained in managed forests. For example, decaying logs and the conifer seedlings that often grow on them are rare under certain canopies such as deciduous trembling aspen (Populus tremuloides Michx.). We conducted a seeding experiment to evaluate the role of certain substrates, and litterfall, on early conifer survivorship. Seeds of balsam fir (Abies balsamea (L.) Mill.), white spruce (Picea glauca (Moench) Voss), and eastern white-cedar (Thuja occidentalis L.) were sown during 2 consecutive years on mineral soil, relocated logs, and litter in deciduous aspen and coniferous (Thuja occidentalis dominated) stands. Seedling survivor ship was monitored at the end of the first growing season and 1 year after each sowing. Conifer seedling survivorship was equivalent or greater under aspen than under cedar-dominated canopies. Picea and Thuja survivorship was highest on decaying logs of approximately 9 cm high (compared with logs buried at forest floor level) and lowest on forest floor litter during both the first growing season and the following autumn–winter. Abies survivorship was little affected by substrate type, except for low autumn–winter survival on litter. Thuja autumn–winter survival was significantly reduced by litterfall in both deciduous and coniferous stands.

The effect of increasing elevation on leaf cuticle thickness and cuticular transpiration in balsam fir

1984 ◽  
Vol 62 (11) ◽  
pp. 2423-2431 ◽  
Author(s):  
Evan H. DeLucia ◽  
Graeme P. Berlyn
Keyword(s):  
Water Loss ◽  
Abies Balsamea ◽  
Dry Weight ◽  
Growing Season ◽  
Elevational Gradient ◽  
First Year ◽  
Tree Line ◽  
Forest Limit ◽  
Cuticle Thickness ◽  
High Elevations

First-year needles and stems of Abies balsamea were collected at the end of the growing season along an elevational gradient on Mt. Moosilauke, NH. Tissue was sampled from the base (732 m), midslope (1143 m), forest limit (1402 m), and tree line (1455 m). Mean cuticle thickness on the adaxial needle surface decreased with increasing elevation from 3.01 to 2.21 μm. A similar decline was observed for the cutinized cell wall at the lower three elevations. Associated with the decline in cuticular thickness was a 59.3% increase in the rate of cuticular water loss per gram dry weight from 732 to 1402 m. The amount of epicuticular wax and other features of leaf anatomy were also examined along the elevational gradient. The high rates of cuticular water loss in these subalpine trees increase the risk of desiccation damage at high elevations and support the concept that they can be a contributing factor in the formation of alpine tree line.

A comparison of seasonal patterns of photosynthate production and use in branches of red spruce saplings at two elevations

1991 ◽  
Vol 21 (4) ◽  
pp. 455-461 ◽  
Author(s):  
Christian P. Andersen ◽  
Samuel B. McLaughlin ◽  
W. Kelly Roy
Keyword(s):  
Carbon Assimilation ◽  
Growing Season ◽  
Red Spruce ◽  
Seasonal Patterns ◽  
Sink Strength ◽  
Great Smoky Mountains ◽  
Sink Activity ◽  
Lower Elevation ◽  
Branch Biomass ◽  
High Elevations

Seasonal patterns of carbon transport from 14C-labeled foliage were examined in red spruce (Picearubens Sarg.) branches at 1935 and 1720 m elevations in the Great Smoky Mountains National Park to characterize possible physiological mechanisms underlying the observed reductions in growth at high elevations. Current and 1-year-old foliage was labeled on 5- to 7-year-old branches of sapling-sized trees in June, August, and October. Retention of 14C was measured after 24 h, and allocation to other branch segments was characterized after 7 days. Total 14C-labeled carbon assimilation was greater in current than in 1-year-old foliage throughout the growing season. This suggests that photosynthetic capacity is high in developing foliage prior to needle maturity and remains high during the first growing season. In August, 14C retention in labeled foliage was less at the higher than at the lower elevation site, possibly reflecting increased respiratory losses that had been previously reported at the higher site. Retention of 14C in current-year shoots as a percent of 14C remaining after 7 days, a measure of sink strength, was high at both sites in June and remained high throughout the season in current-year shoots at the higher elevation site. The relatively high sink activity coupled with the large apportionment of biomass to current-year shoots (19.9 and 26.7% of total branch biomass at the lower and higher elevation sites, respectively) may make red spruce particularly susceptible to stresses such as winter injury that affect young foliage. In addition, the relatively greater sink activity of current-year shoots at the higher elevation site in August and October suggests that the contribution of current-year foliage to overall tree growth may be less at the higher than at the lower elevation site.

scholarly journals Occurrence of 23-epi-26-deoxyactein and Cimiracemoside A in Various Black Cohosh Tissues Throughout the Growing Season

HortScience ◽  
2007 ◽  
Vol 42 (3) ◽  
pp. 535-539 ◽  
Author(s):  
Andrew L. Thomas ◽  
Richard J. Crawford ◽  
George E. Rottinghaus ◽  
John K. Tracy ◽  
Wendy L. Applequist ◽  
...  
Keyword(s):  
Dry Weight ◽  
Growing Season ◽  
Black Cohosh ◽  
Perennial Herb ◽  
Plant Tissues ◽  
Seasonal Patterns ◽  
Cimicifuga Racemosa ◽  
Phytochemical Content ◽  
Actaea Racemosa ◽  
Leaf Tissues

Black cohosh [Actaea racemosa L.; Cimicifuga racemosa (L.) Nutt.] is a perennial herb native to North America that is commonly used for the treatment of menopausal symptoms. The plant is almost exclusively harvested from the wild and is being threatened by overharvesting in some regions. As demand for this plant continues to increase, the potential for profitable cultivation of this species is becoming realistic. Little is known about the effect of various cultivation practices, soils, environments, and harvest times on the multitude of phytochemicals that occur in black cohosh. Furthermore, although the rhizome is the organ that is traditionally consumed, other tissues also contain various quantities of important phytochemicals, but this has not been well documented. The objectives of this study, therefore, were to ascertain any environmental effects on the production of two representative phytochemicals (23-epi-26-deoxyactein and cimiracemoside A) and to elucidate any season-long patterns or variations in the production of these compounds within five black cohosh tissues (leaf, rachis, rhizome, root, and inflorescence). All black cohosh tissues contained 23-epi-26-deoxyactein with substantially more, as a percentage of dry weight, detected in inflorescence (28,582 to 41,354 mg·kg−1) and leaf (8250 to 16,799 mg·kg−1) compared with rhizome (2688 to 4094 mg·kg−1), and all tissues experienced a linear season-long decrease in occurrence of this compound. Cimiracemoside A was not detected in leaf tissues. The highest levels were found in rhizome (677 to 1138 mg·kg−1) and root (598 to 1281 mg·kg−1), which likewise experienced a significant season-long decrease in this compound, whereas levels in the rachis (0 to 462 mg·kg−1) increased over time. In general, environmental factors did not affect production of either compound. Varying seasonal patterns in phytochemical production, combined with differences in phytochemical content among plant tissues, point to the potential for more targeted horticultural production of these and other medicinal compounds within black cohosh.

Genomic variability in the vascular cambium of Abies balsamea

1989 ◽  
Vol 67 (4) ◽  
pp. 990-996 ◽  
Author(s):  
E. J. Mellerowicz ◽  
R. T. Riding ◽  
C. H. A. Little
Keyword(s):  
Dna Synthesis ◽  
Abies Balsamea ◽  
Growing Season ◽  
Cambial Activity ◽  
Balsam Fir ◽  
Genomic Variability ◽  
Cambial Age ◽  
Dna Contents ◽  
Time Of Year ◽  
Quiescent Stage

DNA content was measured cytophotometrically in Feulgen-stained nuclei of fusiform cambial initials from 1- (twig) and 19-year-old (stem base) cambia of balsam fir (Abies balsamea) trees throughout the season. Telophase (2C) and prophase (4C) DNA contents varied with both cambial age and time of year. Maximum DNA contents were observed at the beginning of cambial activity in April. They were lower in the 1-year-old cambium (42.3 (2C) and 84.3 (4C) pg DNA) than in the 19-year-old cambium (59.4 (2C) and 111.1 (4C) pg DNA). The DNA levels decreased during the cambial growing season, attaining minimal values in September of 28.3 (2C) and 53.5 (4C) pg and 37.9 (2C) and 74.5 (4C) pg in the 1- and 19-year-old cambia, respectively. In the autumn, cells accumulated in the G1 phase of the cell cycle. DNA synthesis then took place increasing the 2C levels from the minimum values to the maximum values. This DNA synthesis in 1-year-old cambia started before the beginning of the transition from the resting to the quiescent stage of dormancy.

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