Is long primary growth associated with stem sinuosity in Douglas-fir?

2006 ◽  
Vol 36 (9) ◽  
pp. 2351-2356 ◽  
Author(s):  
Barbara L Gartner ◽  
G R Johnson

Stem sinuosity is a highly visible stem-form trait in the leaders of fast-growing Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) trees, yet its cause is unknown. We tested the hypotheses that sinuous stems have longer expanses of primary growth than nonsinuous stems (putting the leader at higher risk for curvature, induction of compression wood formation, and possibly overcorrection) and higher leader angle using 4- to 5-year-old saplings in raised beds. As hypothesized, sinuous stems had longer expanses of primary growth than did nonsinuous stems (13.5 vs. 12.3 cm, respectively). However, for the dates for which growth (length/day, primary growth, secondary growth, and total growth) differed significantly among sinuosity class, sinuosity class only explained 15%–21% of the variation in growth rate. There were no significant differences in leader angle for saplings of the three sinuosity classes. Contingency tables indicated some consistency in the category of sinuosity to which we assigned the stems in 2001 and 2002 (χ2 = 11.2, p < 0.004). When we used a more quantitative measure, the ratio of stem length/stem distance, there was a tendency toward a significant relationship between the two years (r = 0.272, p = 0.0893). These data suggest that, counter to expectation, the rate of stem growth was not a large factor in determining whether leaders become sinuous for this population of trees.

1994 ◽  
Vol 24 (2) ◽  
pp. 286-296 ◽  
Author(s):  
K.H. Rensing ◽  
J.N. Owens

Bud and cambial zone phenologies of outdoor-grown, containerized seedlings of Pseudotsugamenziesii (Mirb.) Franco (Douglas-fir) were determined and compared. Morphological characteristics of the live primordial shoots were related to known stages of bud development, while cambial zone phenology was based on anatomical characteristics. Secondary growth in branches of P. menziesii seedlings was separated into six stages: (i) early wood formation; (ii) latewood formation; (iii) cessation of cambial cell division; (iv) dormancy; (v) cambial cell expansion; and (vi) resumption of cell division. Early wood formation by the cambial zone, and primary leaf initiation in the shoot tips occurred until July. During this time of maximal activity, differences in wall thickness and shape distinguished cambial cells from vascular cells in early differentiation stages. By late July, earlywood formation was changing to latewood formation and bud-scale initiation had begun. The transition to preformed leaf initiation in the buds occurred over a period of 1 month in August and September. Cambial cell division ceased in early September but tracheid differentiation continued until about the end of October. Preformed leaf initiation lasted until the buds became dormant in mid-November. The cambial zone was dormant from the end of November until the beginning of March, and in transverse section was characterized by a distinct boundary at the border of the xylem and regular, cigar-shaped cambial cells with thick radial walls. Resumption of cambial activity in the 1st week of April began with radial expansion, followed about 2 weeks later by cell division. Differentiation of earlywood tracheids and bud swelling began in early April. The majority of buds flushed in the 3rd week of April. Rays in the lateral shoots were composed of monoseriate files of radially elongated cells. Ray initials were not observed. Ultrastructural features indicated that the dictyosomes of the cambial cells were active during the winter period.


2006 ◽  
Vol 36 (3) ◽  
pp. 719-724 ◽  
Author(s):  
Domenico Morabito ◽  
Aurore Caruso ◽  
Sabine Carpin ◽  
Cédric Carli ◽  
Françoise Laurans ◽  
...  

Populus tremula Michx. × Populus alba L. clone 717-1B4 plants were grown in a hydroponic system in an effort to detect cambial activity in a changing nutrient environment. The secondary growth of the stem was determined by automated measurement of radial growth, as well as by histological study. This is the first time poplar cambial activity has been recorded in a hydroponic system. Further, we demonstrate that nutrient limitations can be tested with progressive deprivation of liquid medium. The system lends itself to measurements of stomatal conductance, primary stem growth, leaf growth, and radial stem growth. In this study we found that primary and secondary growth were affected by nutrient solution limitations. This hydroponic system will be valuable in elucidating the impact of environmental, physiological, and molecular factors on cambial activity and wood formation.


2003 ◽  
Vol 33 (9) ◽  
pp. 1602-1609 ◽  
Author(s):  
Stephen J Mitchell

Three-year-old coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in a factorial experiment with three levels of shading (0, 30, and 60%), three levels of mechanical stimulus (staked, freestanding, and bent), and two levels of nitrogen fertilization (0 and 200 kg/ha) to investigate the separate and combined effects of these factors on morphology and bending resistance. Fertilization increased branch angle and increased the sensitivity of branch and leader extension to bending stresses but did not affect volume increment, stem form, or bending resistance. The effects of shading and mechanical treatments on morphology were independent and additive. Shading reduced stem diameter and volume increment, but did not affect height increment, producing more slender trees. Bending produced less slender trees through a combination of reduced height increment and increased diameter increment. Staking did not affect tree morphology. Trees under heavy shade were responsive to bending but were more slender and had lower bending resistance than unshaded trees with the same mechanical stimulus. These results point towards the biological basis for the development of tree instability in high density stands.


2020 ◽  
Vol 19 (1) ◽  
pp. 75-86
Author(s):  
Chanyut Sudtongkong ◽  
◽  
Sinlapachai Senarat ◽  
Supparat Kong-oh ◽  
Pisit Poolprasert ◽  
...  

Informative reviews on the oocyte atresia referring to degeneration and resorptive mechanism are warranted in common animals, but it is rarely still found in carbs. In this current study, we focused on characteristics and stage of the atretic oocyte from two important female sesarmid carbs (violet vinegar crab, Episesarma versicolor, and Singapore vinegar crab, E. singaporense) during ovarian maturation. A total of 30 female samples in each carb species were collected from the Palian mangrove area of Trang province, Thailand. The results shared among those carb samples that both primary growth (PGs) and secondary growth (SGs) phases underwent a degenerative process of atresia. The latter of atresia during SGs was also divided into five stages (I, II, III, IV, and V). The degeneration of follicular cell and yolk architecture identifying in the SGs were highlighted. The number of atresias was slightly compared between E. versicolor and E. singaporense; therefore, there were no significant differences. Our observation suggested that the low number of atresia might be associated with the increased reproductive success of two female sesarmid carb living in natural habitats.


2018 ◽  
Vol 24 (3) ◽  
pp. 255-260
Author(s):  
Carlos Eduardo Ferreira de Castro ◽  
Ana Cecilia Ribeiro Castro ◽  
Charleston Gonçalves ◽  
Vivian Loges

Many species of Zingiber have great ornamental potential, due to durability and exotic appearance of the inflorescences. Despite its large phenotypic variability, they are scarcely exploited or not yet exploited regarding the ornamental potential. To conserve potential ornamental genotypes, and subsidize breeding program, the Agronomic Institute (IAC) maintain a Germoplasm Collection of Ornamental Zingiberales with promising accessions, including Zingiber. The aim was the morphophenological characterization of ten Zingiber accessions and the indication for landscape purposes. A large variation was observed to the evaluated characters: Clump height (CH); Inflorescence visualization (IV); Clump area (CA); Clump density (CD); Leaf stem Firmness (LSF); Number of leaf stems per clump (NLSC); Number of leaves per stem (NLS); Leaf color (LCol); Evergreen tendency (ET); Flower stem growth (FSG); Flower stem length (FSLe); Flower stem diameter (FSD); Flower stem per clump (FSC); Color sensorial perception (CSP); Flower stem weight (FSW); Inflorescence length (IL); Inflorescence diameter (ID); Bracts aspects (BAs); and Flowering season (FSe). The accessions very suitable and with the best performance to use for landscape purpose were Z. spectabile, IAC Anchieta (Z. spectabile), Z. newmanii.


IAWA Journal ◽  
1988 ◽  
Vol 9 (3) ◽  
pp. 269-274 ◽  
Author(s):  
Frank W. Telewski

The majority of detailed studies on circumnutational growth movements have focused on herbaceous plants or on the primary growth of woody plant seedlings, ignoring completely secondary growth in woody plants. The relatively rapid movement in herbaceous tissues consists of two components: an autonomous growth rhythm and a gravitropic response. Since there is a gravitropic component to circumnutational movement and a gravitropic stimulus can induce compression wood formation, the formation of a compression wood spiral may be expected if there is a circumnutational movement of a woody stern. It is suggested here, that observed spirals of compression wood within annual growth rings in Pinus taeda L. and Abies concolor (Gord. ' Glend.) Lindl. ex Hildebr. represents an annual record of a slower circumnutational growth movement. Data derived from observations of greenhouse- grown 3-year-old Pinus taeda seedlings indicate that there are two distinct circumnutational patterns of different rotation al frequency present in woody plants associated with primary and secondary tissues.


Holzforschung ◽  
1970 ◽  
Vol 24 (2) ◽  
pp. 68-70 ◽  
Author(s):  
Fredric P. Riech ◽  
Kim K. Ching

1987 ◽  
Vol 67 (1) ◽  
pp. 185-192 ◽  
Author(s):  
H. T. KUNELIUS ◽  
J. A. MACLEOD ◽  
K. B. MCRAE

Urea and ammonium nitrate were applied at 30, 60, 90 and 120 kg N ha−1 in spring and after cutting the primary growth of timothy and bromegrass in three field experiments. Dry matter yields of timothy and bromegrass and total nitrogen concentration of tissue and nitrogen yields of timothy were determined. Loss of nitrogen as ammonia was monitored on microplots between the end of May and early July. Primary growth yields were usually similar for ammonium nitrate and urea but in the secondary growth timothy fertilized with ammonium nitrate outyielded timothy fertilized with urea in four out of six harvest years. Dry matter response to applied nitrogen was usually curvilinear in primary growth but linear in secondary growth over the nitrogen rates studied. Total nitrogen concentration in primary and secondary growths of timothy increased linearly with nitrogen rate during the initial 2–3 yr; ammonium nitrate and urea were equally effective in all but one harvest year. Total nitrogen production of timothy also increased linearly over the range of 30–120 kg N ha−1, while ammonium nitrate outyielded urea-fertilized timothy during one season in primary and two seasons out of four in secondary growth. Nitrogen losses increased from spring to summer, in general, with 68–75% of the variation explained by air temperature. Urea and ammonium nitrate were considered equivalent nitrogen sources for the primary growth of timothy but urea was less efficient in the secondary growth under summer conditions.Key words: Urea, ammonium nitrate, timothy, bromegrass, ammonia losses


2009 ◽  
Vol 27 (2) ◽  
pp. 147-157 ◽  
Author(s):  
Geoffrey M. Downes ◽  
David Drew ◽  
Michael Battaglia ◽  
Detlef Schulze
Keyword(s):  

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