A note on root development, bud activity, and survival of Douglas-fir, and survival of western hemlock and noble-fir seedlings, following exposure to ethylene during cold storage

1992 ◽  
Vol 22 (8) ◽  
pp. 1195-1200 ◽  
Author(s):  
John I. Blake ◽  
Robert G. Linderman

Three cold storage experiments were conducted with bare-root Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings from coastal Oregon and eastern Washington Cascade sources. The objectives were to determine the effects of ambient, below-ambient (KMnO4 pellets), and 0.5 and 5 ppm ethylene during short-term storage on subsequent root development (expt. 1) and bud activity (expt. 2), and to relate these results to survival in the field after prolonged cold storage (expt. 3). Root numbers and lengths were measured 28 days following a 7-day storage period after lifting seedlings on September 27 and December 1. In the coastal source, root numbers and lengths in the 5 ppm ethylene treatment were, respectively, 46 and 49% greater in September, and 22 and 13% greater in December, than the controls. No comparable treatment effects were found for the Cascade source. Neither the KMnO4 nor the 0.5 ppm ethylene treatments affected root development in either seed source. For terminal buds in the controls, the number of days to 50% bud break was increased 2–8 days by a 30-day cold storage period compared with a 7-day period. For the coastal source, no increase in the time to 50% bud break was observed in the 5 ppm ethylene treatment. Seedling survival was evaluated in the field for the same treatments following 4 months cold storage for the Douglas-fir sources, coastal western hemlock (Tsugaheterophylla (Raf.) Sarg.), and noble fir (Abiesprocera Rehd.). Survival for the 5 ppm ethylene treatment compared with the control was increased by 55% in the coastal Douglas-fir source and by 13% in western hemlock. These results suggest that stimulated root development and bud activity may be partially responsible for the observed survival increase following cold storage at elevated ethylene levels.

1985 ◽  
Vol 15 (5) ◽  
pp. 935-940 ◽  
Author(s):  
Don Minore

The effects of sowing depth of seeds of several western forest tree species were studied in greenhouse experiments. Emergence and seedling weight of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco), western hemlock (Tsugaheterophylla (Raf.) Sarg.), and noble fir (Abiesprocera Rehd.) were reduced by sowing seeds in soil at depths greater than 1 cm. Deep sowing in a peat–vermiculite mixture also reduced the emergence of Douglas-fir and western hemlock, but increased the hypocotyl diameters and weights of Douglas-fir seedlings.


1986 ◽  
Vol 16 (3) ◽  
pp. 471-475 ◽  
Author(s):  
Chao-Hsiung Tung ◽  
Luci Wisniewski ◽  
David R. DeYoe

Survival, phenology, and growth performance of 2 + 0 Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) and noble fir (Abiesprocera Rehd.) seedlings planted at 1500 m in the Oregon Cascade Range were determined following a lifting on November 7 with 7 months of cold storage or lifting on March 1 with 3 months of cold storage. Storage temperature remained between 1 and 2 °C. There was no difference in Douglas-fir survival attributable to the lifting – cold-storage treatments during the first two growing seasons. The first-season survival of noble fir stored for 7 months was superior to that of those stored for 3 months, but no difference was evident after the second growing season. Timing of bud burst did not differ significantly among treatments for either species. However, the rate of bud burst was significantly greater for noble fir seedlings lifted in November and stored 7 months than for those lifted in March and stored 3 months. No difference in the rate of bud burst was observed between treatments for Douglas-fir. Shoot/root ratio for both species and treatments decreased significantly in the first growing season, but did not change significantly in the second growing season. Regardless of species, no differences were found in height growth or diameter increment between the two lifting – cold-storage treatments for the two consecutive growing seasons. The results suggest that Douglas-fir and noble fir seedlings originating from high-elevation seed sources can be lifted in fall and cold stored for 7 months without adverse effects on seedling performance.


1993 ◽  
Vol 11 (3) ◽  
pp. 119-123
Author(s):  
J. Roger Harris ◽  
Nina L. Bassuk ◽  
Thomas H. Whitlow

Abstract Dormancy level, days to bud break, root regrowth and rate of shoot extension were determined for 18-in seedlings of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco), paper birch (Betula papyrifera Marsh.) and green ash (Fraxinus pennsylvanica Marsh.) subjected to varying durations of cold storage. Douglas fir seedlings did not break bud unless exposed to at least 4 weeks of cold storage, but bud break was unaffected by further time in cold storage. The number of regenerated roots increased with time in cold storage until 12 weeks of chilling and decreased sharply thereafter. Days to bud break of paper birch and green ash decreased as chilling time accumulated. Full dormancy release and maximum root regeneration of paper birch coincided at 10 weeks of chilling. Green ash achieved full dormancy release after 14 weeks of cold storage. The number of roots regenerated increased with cold storage duration for green ash. Shoot extension rate of all species was little affected by chilling duration. Implications for transplanting are discussed.


2001 ◽  
Vol 31 (2) ◽  
pp. 302-312 ◽  
Author(s):  
Thomas J Brandeis ◽  
Michael Newton ◽  
Elizabeth C Cole

In a multilevel study to determine limits to underplanted conifer seedling growth, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), grand fir (Abies grandis (Dougl. ex D. Don) Lindl.), western redcedar (Thuja plicata Donn ex D. Don), and western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings were planted beneath second-growth Douglas-fir stands that had been thinned to basal areas ranging from 16 to 31 m2/ha. Understory vegetation was treated with a broadcast herbicide application prior to thinning, a directed release herbicide application 2 years later, or no treatment beyond harvest disturbance. Residual overstory density was negatively correlated with percent survival for all four species. Broadcast herbicide application improved survival of grand fir and western hemlock. Western redcedar, grand fir, and western hemlock stem volumes were inversely related to overstory tree density, and this effect increased over time. There was a strong indication that this was also the case for Douglas-fir. Reduction of competing understory vegetation resulted in larger fourth-year stem volumes in grand fir and western hemlock.


1955 ◽  
Vol 31 (1) ◽  
pp. 45-59 ◽  
Author(s):  
G. S. Allen ◽  
I. K. Barber ◽  
Ian Mahood

An area of 738 acres about 20 miles north and west of Port Alberni on Vancouver Island was seeded by helicopter to Douglas fir (1/2 pound per acre) and western hemlock (1/5 pound per acre) in November 1951. One week earlier this area and a surrounding buffer strip, totalling 1760 acres, had been baited by helicopter using wheat treated with thallous sulphate and "1080".Baiting was successful and the roden:trap ratio dropped from 1:4.6 to 1:94.3 as a result. By April the ratio had climbed again to 1:18.7. By the first week of June 1952, a total of about 1400 Douglas fir and 840 hemlock had germinated per acre. By November 1952, this had dropped to 1000 Douglas fir and 198 hemlock per acre. A final extensive survey in June 1954, showed a total of 730 Douglas fir and 57 hemlock of the 1952 crop per acre with a milacre stocking of 42.0 percent for Douglas fir and 43.9 percent for Douglas fir and hemlock. The 4-milacre stocking due to the 1952 Douglas fir seedlings was 78.3 percent. Practically all of the seedlings that germinated in 1952 are attributed to the seeding operation because of the relatively uniform distribution of seedlings and the lack of seedlings on the control area.The seeding operation in itself restocked 628 acres to B.C. Forest Service minimum standards (31 percent by 1-milacres). It restocked 708 acres to U.S. "medium" or "good" standards. With natural trees included, only 28 acres are below B.C. Forest Service standards, and 6 acres below U.S. "medium" stocking. Total stocking, including natural trees, is 59.3 percent by 1-milacres and 88.6 percent by 4-milacres.The baiting and seeding operation can be considered highly successful. The surviving Douglas firs are healthy and vigorous and show little deer or grouse damage to date. Distribution of the seedlings is good and most gaps that occurred are believed due to uneven local distribution of seed. Considering that this experiment was carried out on a rather steep south exposure and that the first summer following seeding was unusually hot and dry, the satisfactory results suggest that direct seeding following rodent control has a definite place in West Coast forestry practice. It may well take the place of more expensive and troublesome planting on many areas that are slow to restock.


2021 ◽  
Vol 22 (9) ◽  
pp. 4437
Author(s):  
Han Ryul Choi ◽  
Min Jae Jeong ◽  
Min Woo Baek ◽  
Jong Hang Choi ◽  
Hee Cheol Lee ◽  
...  

Cold storage of peach fruit at low temperatures may induce chilling injury (CI). Pre-storage 1-MCP and high CO2 treatments were reported among the methods to ameliorate CI and reduce softening of peach fruit. However, molecular data indicating the changes associated with pre-storage 1-MCP and high CO2 treatments during cold storage of peach fruit are insufficient. In this study, a comparative analysis of the difference in gene expression and physico-chemical properties of fruit at commercial harvest vs. stored fruit for 12 days at 0 °C (cold-stored (CS), pre-storage 1-MCP+CS, and pre-storage high CO2+CS) were used to evaluate the variation among treatments. Several genes were differentially expressed in 1-MCP+CS- and CO2+CS-treated fruits as compared to CS. Moreover, the physico-chemical and sensory data indicated that 1-MCP+CS and CO2+CS suppressed CI and delayed ripening than the CS, which could lead to a longer storage period. We also identified the list of genes that were expressed commonly and exclusively in the fruit treated by 1-MCP+CS and CO2+CS and compared them to the fruit quality parameters. An attempt was also made to identify and categorize genes related to softening, physiological changes, and other ripening-related changes. Furthermore, the transcript levels of 12 selected representative genes from the differentially expressed genes (DEGs) in the transcriptome analysis were confirmed via quantitative real-time PCR (qRT-PCR). These results add information on the molecular mechanisms of the pre-storage treatments during cold storage of peach fruit. Understanding the genetic response of susceptible cultivars such as ‘Madoka’ to CI-reducing pre-storage treatments would help breeders release CI-resistant cultivars and could help postharvest technologists to develop more CI-reducing technologies.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 910
Author(s):  
María I. Sáez ◽  
María D. Suárez ◽  
Francisco J. Alarcón ◽  
Tomás F. Martínez

This study evaluates the potential of different algae extracts (Crassiphycus corneus, Cc; Ulva ohnoi, Uo; Arthrospira platensis, Ap; Haematococcus pluvialis, Hp) as additives for the preservation of rainbow trout fillets. The extracts were prepared with different water to ethanol ratios from the four algae species. The highest ferric reducing antioxidant power (FRAP) was observed in Uo extracted in 80% ethanol. Ap aqueous extract also had considerable FRAP activity, in agreement with a high total phenolic content. Radical scavenging activity (DPPH) was higher in Cc 80% ethanol extract, in agreement with a high total carotenoid content. In fact, when the algae aqueous extracts were assayed on the fish fillets, their antioxidant activity exceeded that of ascorbic acid (ASC). All algae extracts delayed microbial growth and lipid oxidation processes in trout fillets throughout the cold storage period compared to controls, and also improved textural parameters, these effects being more evident for Ap and Hp. With respect to the color parameters, the Hp extract prevented the a* values (redness) from decreasing throughout cold storage, a key point when it comes to colored species, not least salmonids. On the other hand, the Ap extract was not as effective as the rest of treatments in avoiding a* and b* decrease throughout the storage period, and thereby the color parameters were impaired. The results obtained, together with the natural origin and the viability for large-scale cultivation, make algae extracts interesting fish preservative agents for the food industry.


Plant Disease ◽  
2013 ◽  
Vol 97 (6) ◽  
pp. 744-748 ◽  
Author(s):  
Jerry E. Weiland ◽  
Bryan R. Beck ◽  
Anne Davis

Pythium species are common soilborne oomycetes that occur in forest nursery soils throughout the United States. Numerous species have been described from nursery soils. However, with the exception of P. aphanidermatum, P. irregulare, P. sylvaticum, and P. ultimum, little is known about the potential for other Pythium species found in nursery soils to cause damping-off of tree seedlings. A greenhouse study was conducted to evaluate the pathogenicity and virulence of 44 Pythium isolates representing 16 species that were originally recovered from soil at three forest nurseries in Washington and Oregon. Seeds of Douglas-fir (Pseudotsuga menziesii) were planted into soil infested with each of the isolates. Seedling survival, the number of surviving seedlings with necrotic root lesions, and taproot length were evaluated 4 weeks later. Responses of Douglas-fir to inoculation varied significantly depending on Pythium species and isolate. Eight species (P. dissotocum, P. irregulare, P. aff. macrosporum, P. mamillatum, P. aff. oopapillum, P. rostratifingens, P. sylvaticum, and P. ultimum var. ultimum) significantly reduced the number of surviving seedlings compared to the noninoculated treatment. However, all Pythium species caused a greater percentage of seedlings to develop root lesions (total mean 40%) than was observed from noninoculated seedlings (17%). Taproot length varied little among Pythium treatments and was not a useful character for evaluating pathogenicity. Results confirm the ability of P. irregulare, P. mamillatum, and P. ultimum var. ultimum to cause damping-off of Douglas-fir seedlings, and are indicative that other species such as P. dissotocum, P. aff. macrosporum, P. aff. oopapillum, P. rostratifingens, and P. sylvaticum may also be responsible for seedling loss.


Mycologia ◽  
1971 ◽  
Vol 63 (3) ◽  
pp. 567-574 ◽  
Author(s):  
A. Funk ◽  
R. A. Shoemaker
Keyword(s):  

1997 ◽  
Vol 75 (9) ◽  
pp. 1424-1435 ◽  
Author(s):  
D. Mailly ◽  
J. P. Kimmins

Silvicultural alternatives that differ in the degree of overstory removal may create shady environments that will be problematic for the regeneration of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Gradients of light in the field were used to compare mortality, growth, and leaf morphological acclimation of two conifer species of contrasting shade tolerances: Douglas-fir and western hemlock (Tsuga heterophylla (Raf.) Sarg.). Results after two growing seasons indicated that Douglas-fir mortality occurred mainly at relative light intensity (RLI) below 20%, while western hemlock mortality was evenly distributed along the light gradient. Height, diameter, and biomass of the planted seedlings increased with increasing light for both species but at different rates, and maximum biomass accumulation always occurred in the open. Douglas-fir allocated more resources to stem biomass than western hemlock, which accumulated more foliage biomass. Increases in specific leaf area for Douglas-fir seedlings occurred at RLI ≤ 0.4 and red/far red (R/FR) ratio ≤ 0.6, which appear to be the minimal optimum light levels for growth. Conversely, western hemlock seedlings adjusted their leaf morphology in a more regular pattern, and changes were less pronounced at low light levels. These results, along with early mortality results for Douglas-fir, suggest that the most successful way to artificially regenerate this species may be by allowing at least 20% of RLI for ensuring survival and at least 40% RLI for optimum growth. Key words: light, light quality, leaf morphology, acclimation.


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