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1.
The effect of warm storage (15°C) for 0, 15 or 31 days, applied after cold storage until April, and date of lifting to cold
storage on the physiological condition and field performance of two-year-old oak seedlings (Quercus robur L.) was investigated. Assessments before planting included plant moisture status, root and shoot dry weight, root growth
potential (RGP), while after planting root growth, shoot growth phenology, shoot and root dry matter accumulation and stem
quality were assessed. Warm storage effects were large, but lift date effects were small. Warm storage for 31 days reduced
height and diameter growth, stem quality, total biomass, root growth, and reduced stem quality in the field, but 15 days storage
had a smaller effect. Warm storage delayed bud break and shoot growth cessation but survival was unaffected. The depletion
of food reserves during storage and low moisture availability might have caused shoot dieback leading to the development of
poor quality stems. There was evidence that dry weight fraction of both the shoot tip and the taproot provided good information
on the quality of the stock before planting. RGP was also a good indicator of quality. Electrolyte leakage readings from fine
and taproots were not reliable indicators of plant quality. 相似文献
2.
3.
以普通油茶作砧木和接穗进行大树嫁接换冠,研究不同嫁接条件对油茶接穗成活及生长的影响。结果表明:砧木年龄、嫁接时期、接穗保存时间对接穗成活有显著影响,断砧高度对接穗成活没有显著影响;砧木年龄、断砧高度、嫁接时期对接穗新梢长度有显著影响,接穗保存时间在接穗成活后对新梢长度没有显著影响。选择20 a砧木+25~50 cm断砧高度+6月上旬+采穗当天嫁接,最有利于提高油茶的嫁接成活率和新梢长度。 相似文献
4.
Planting stock type and quality can have an important impact on early growth rates of plantations. The goal of this study was to evaluate early growth and root/shoot development of different planting materials in typical heavy clay soils of northwestern Quebec. Using one-year-old bareroot hybrid poplar dormant stock, four planting materials were compared: (1) regular bareroot stock, (2) rootstock (stem pruned before planting), (3) whips (roots pruned before planting), and (4) cuttings (30 cm stem sections taken from the basal portion of bareroot trees, i.e. roots and shoot pruned). Rooted stock types (bareroot and rootstock) produced, on average, 1.2 times larger trees than unrooted stock types (cuttings and whips). However, shoot-pruned stock types (rootstocks and cuttings) reached similar heights and basal diameters as unpruned stock types (bareroots and whips), during the first growing season. Shoot pruning reduced leaf carbon isotopic ratios, suggesting that unpruned stock types were water-stressed during the first growing season. The stress was most likely caused by early leaf development while root growth occurred later in the summer. We conclude that shoot pruning bareroot stock is a useful management option to reduce planting stress without compromising early growth rates of hybrid poplars. 相似文献
5.
D. S. Thomas 《New Forests》2009,38(3):245-259
Forestry requires low mortality of transplanted seedlings. Mortality shortly after planting is often associated with inadequate
hydration of transplants. Seedlings can be hardened to the drought conditions they may experience after transplanting by exposing
them to controlled drought conditions in the nursery. Eucalyptus pilularis Sm. seedlings were drought hardened by providing nil (severe treatment) or half (mild treatment) the daily irrigation routinely
received (control treatment) for up to two non-consecutive days per week during the last 4 weeks of growth in the nursery.
Drought hardening reduced stem diameter, seedling leaf area, leaf area per root biomass and seedling quality measured by the
Dickson quality index, but increased root:shoot ratio. Hardened seedlings had lower stomatal conductance and leaf water potential
on the days they received less irrigation that the control treatment. Hardened seedlings had greater stomatal conductance
and were less water stressed than seedlings experiencing drought for the first time indicating hardened seedlings had adjusted
physiologically to drought. Survival after transplanting in the controlled drought environment in a glasshouse was enhanced
by the hardening treatments. Non hardened seedlings that had had their upper leaves manually removed immediately prior to
transplanting to reduce leaf area (top-clipped) had similar survival to hardened seedlings. Stomatal conductance and leaf
water potential after transplanting were higher in hardened and top-clipped seedlings than unhardened control seedlings or
vegetative cuttings. Survival in the field trial was over 95% for all treatments, possibly as rain fell within 4 days of planting
and follow-up rain occurred in the subsequent weeks. Neither the hardened or top-clipped seedlings planted in the field trial
had reduced growth, increased propensity to form double leaders or worse stem form than control seedlings when measured at
age 3 years. 相似文献
6.
It has become apparent that some interventions are required to aid the regeneration of woody species in the Sudanian savanna. Direct seeding has been ineffective, thus planting high quality seedlings may be a viable alternative. In this study, we examined the stock quality of two valuable Sudanian savanna species, Acacia macrostachya and Pterocarpus erinaceus. Different nursery production periods were tested as well as the species’ field performance under well-watered and stressed conditions. The results showed that older seedlings (9-month) were morphologically distinct from younger ones (3-month), particularly in the case of P. erinaceus. Eighteen months after planting out, survival and growth of seedlings were not affected by initial seedling size; this was the result of the high root to shoot ratio of seedlings in all age groups at the time of planting. Seedling mortality as high as 30% was observed and attributed to both drought stress and other factors such as herbivory. Regression analyses revealed that initial shoot height was a poor predictor of field performance for both species, but initial root collar diameter accounted for 25% of the variation in diameter of P. erinaceus in the field. We conclude that initial seedling size does not affect survival and growth in the field provided that all sizes of seedling have a high root to shoot ratio at the time of planting. The prediction of field performance could be improved by developing a model that incorporates a wide range of root collar diameter. 相似文献
7.
The normal delays in the production of useful planting materialin tree species such as Quercus robur from both seedlings andcuttings can be overcome by growing the plants at relativelyhigh temperature and in continuous light. Top growth could befurther accelerated by application of gibberellic acid (GA3)as foliar spray. There were, however, distinct differences inresponse between seedlings (with a high root: top dry matterratio, 4:1), and freshly rooted cuttings. The latter evincedonly onefifth the seedling response, but when cuttings attainedsimilar root:top ratios, their response reached that of seedlings. GA3 treatment accelerated top growth at the expense of rootgrowth, but a root dip for 4h in 100 ppm indole-3yl-butyricacid (IBA) given to 4-month-old cuttings restored root growthto normal even with GA3 treatment. During rooting, cutting commonlybecame dormant but this was prevented by foliar GA3 sprays.Growth was further and substantially improved by inclusion ofcytokinin in such sprays (benzylandenine purine, BAP). Furtherimprovements of growth were obtained by 5% sucrose suppliedto the foliage. In field experiments, assessing establishmentof seedlings and cuttings, the latter established well but after550 days still had not attained the same root:shoot ratio asseedlings. GA3 (50 ppm) again greatly promoted shoot growth,while BAP increased branching and leaf number; when given togethermaximum leaf numbers and shoot dry weight were obtained, yetroot growth remained normal. Further addition of IBA raisedshoot growth still further, but other characters measured sufferedreductions. The potential use of these findings is discussed. 相似文献
8.
《Scandinavian Journal of Forest Research》2012,27(1):26-35
Pedunculate oak (Quercus robur L.) and Scots pine (Pinus sylvestris L.) seedlings were lifted on several occasions during autumn 1997 to determine the relationships between storability and frost hardiness. On each lifting date their physiological status was determined by assessment of shoot and root electrolyte leakage and frost hardiness, assessed as freeze-induced electrolyte leakage. Additional seedlings were simultaneously cold-stored for field planting and assessment of preplanting root growth potential in April 1998. First year field performance was determined the following winter. Storability and cold acclimation patterns differed between the two species. Both were negatively affected by early lifting, but oak was less sensitive with respect to survival, and pine attained tolerance to cold storage more rapidly and earlier with respect to growth increment. The correlations between shoot frost hardiness and performance suggest that freeze-induced shoot electrolyte leakage (SELdiff?20) below a threshold of 5% is a good storability predictor for Scots pine in Denmark. A completely reliable criterion for pedunculate oak could not be established. 相似文献
9.
This research examined the first year growth characteristics of cold stored and transplanted nursery-produced aspen (Populus tremuloides) seedlings (container and bareroot (BR)) and compared it to the growth of seedlings that had not been transplanted (established
from germinants in the field) and therefore had an unrestricted root system (UR). Prior to planting, nursery-produced seedlings
were placed in cold storage (−3°C) and root growth potential (RGP) and total non-structural carbohydrate (TNC) root reserves
were tested at 0, 10, 75 and after 150 (container) and 190 days (BR) of storage. Both container and BR stock had much lower
root to shoot ratios (RSRs) and root carbohydrate reserves compared to UR seedlings after 170 days. During storage, root reserves
in container stock declined faster than in the BR and UR seedlings. RGP in all nursery stock was the highest after 75 days
of storage, while longer storage resulted in shoot dieback and reduced root growth. After the first growing season, UR seedlings
were one tenth the size of the nursery stock; however, in the second growing season they had no stem dieback and grew twice
the height and stem diameter. The higher RSRs and root reserves in the UR seedlings was likely caused by early bud set in
its first year of growth. This suggests that inducing bud set earlier in the growing regime might allow seedlings to increase
root mass and carbohydrate reserves. 相似文献
10.
Root growth potential, seedling morphology and bud dormancy correlate with survival of loblolly pine seedlings planted in December in Alabama 总被引:1,自引:0,他引:1
First-year survival of December-planted loblolly pine seedlings sampled from 20 nurseries ranged from 36 to 86%. Various characteristics of the seedlings including root growth potential (RGP), shoot/root ratio, root weight and stem length were correlated with survival. A regression model using the number of new roots >/= 0.5 cm and the shoot/root ratio accounted for 80% of the variation in first-year survival. Alone, the number of new roots >/= 0.5 cm accounted for 76% of the variation in survival. Foliar nutrients were not correlated with survival. Seedlings with a high proportion of quiescent buds at planting had a higher RGP and better survival than seedlings with dormant (endodormant) buds. The data suggest that seedlings with dormant buds should not be planted on sites where rapid new root growth is needed for survival. 相似文献
11.
Increased planting of hard mast oak species in the Lower Missouri River floodplain is critical as natural regeneration of
oak along the Upper Mississippi and Lower Missouri Rivers has been limited following major flood events in 1993 and 1995.
Traditional planting methods have limited success due to frequent flood events, competition from faster growing vegetation
and white-tailed deer herbivory. Results of early growth response of swamp white oak (Quercus bicolor Willd.) seedlings in relation to initial acorn mass and size, and early rapid shoot growth for seedlings produced by containerized
root production method (RPM™), are presented. Containerized RPM™ seedlings grown in the greenhouse under optimal conditions
demonstrate that seed size had no discernable impact on first-year root or shoot size. Seedling survival for the first two
years and acorn production for the first three years after outplanting are presented, comparing use of containerized RPM™
swamp white oak seedlings to nursery stock. Flood tolerant precocious RPM™ oak seedlings in the floodplain provide a source
of food for acorn-consuming wildlife ten to fifteen years sooner than oaks originating from natural regeneration, direct seeding
or traditional bare root planting. Compared to bare root nursery stock that produced no acorns, some RPM™ swamp white oak
seedlings averaged 4.3, 5.2, and 6.3 acorns/seedling in the first three years after fall outplanting.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
12.
Aging of the donor tree decreased adventitious root formation in shoot cuttings of Tectona grandis Linn. f. (teak). Exogenous application of auxins, i.e., α-naphthalene acetic acid (NAA) and indole-3-butyric acid (IBA) has
a significant positive effect on the percentage of rooting. The maximum percent rooting was obtained with 4,000 ppm IBA as
compared to other treatment. Significant increase in root number was recorded in shoot cuttings treated with 4,000 ppm NAA.
The overall rooting response was better in the treatment with IBA rather than with NAA. Further periodic samples (0, 10, 20,
and 30 days) were taken to assess the total soluble sugar, starch, protein, and peroxidase (PER) activity in the rooting zone
of shoot cuttings of teak during adventitious root formation. Application NAA and IBA to shoot cuttings resulted in an increase
in the level of total soluble sugar, starch, protein, and PER-activity in the rooting zone. The stored carbohydrates were
utilized during adventitious root formation. Hence, total soluble sugar and starch contents of cuttings, irrespective of age
of donor plants, decreased with the passage of time in cuttings planted for rooting. Significant fluctuations were observed
in the protein content of cuttings during the time of root induction. There was an increase in the protein content with the
passage of time from the day of planting up to its 20th day, followed by a sharp decline in the protein content of cuttings
at the 30th day of planting, irrespective of the age of donor plants or the treatment of cuttings with auxins. Irrespective
of donor plant age, PER-activity in the cuttings increased from the day of their planting for rooting up to the 20th day,
and then declined at its 30th day of planting. It was interesting to note that PER-activity remained higher at all stages
in the cuttings of 2-month-old seedlings which rooted profusely as compared to the cuttings of 15- and 30-year-old donor plants
those rooted poorly. This study suggested that the exogenously applied NAA and IBA at different concentration seems to activate
sugar metabolism for release of energy, protein and PER-activity which are necessary for cellular division and differentiation
during adventitious root primordium initiation or development in the rooting zone of shoot cuttings. 相似文献
13.
Heat damage in boxed white spruce (Picea glauca [Moench.] Voss) seedlings: Its pre-planting detection and effect on field performance 总被引:2,自引:0,他引:2
This study investigated the effects of holding 1+0 PSB313a white spruce (Picea glauca (Moench.) Voss) seedlings in storage boxes at air temperatures of 5, 10, 20, 30 and 40°C for 12, 24, 48, 72 and 96 h before planting. The ability to detect physiological damage to seedlings as a result of such treatment, before planting, was also examined. After one growing season, no needle damage or mortality >8% was found for temperature treatments up to 20°C for 4 days. At 30°C and above, seedling damage and mortality increased, while bud flush, shoot height, stem diameter and shoot dry weight decreased with increasing temperature and duration of treatment. Seedling mortality in the field was 100% after the 40°C treatment exposure for 72 h or longer. Pre-planting needle electrolyte leakage was indicative of visible needle damage 14 days after planting, whereas stem electrolyte leakage and root growth potential were more closely related to end of season plantation mortality. Despite the lack of damage observed at 20°C or below, preplanting exposure of white spruce seedlings to temperatures above 5°C, during transportation and field storage, is not recommended. 相似文献
14.
Azamal Husen 《New Forests》2008,36(1):13-27
A study was conducted on the twelve clones of shisham (Dalbergia sissoo Roxb.). These clones were obtained from India and Nepal. Single-node leafy cuttings were prepared from the vegetative multiplication
garden to examine the clonal variation, effect of IBA treatment on rooting response and associated metabolic changes during
adventitious root formation. A remarkable and significant variation was observed due to treatment of 2,000 ppm IBA in the
rooting parameters. Clonal variations were also significant for root and shoot growth while length of root was insignificant.
Among the twelve clones studied; C3 (Tulsipur, Gonda, Uttar Pradesh, India) and C4 (Laxmipur, Gonda, Uttar Pradesh, India)
clone cuttings have given the highest rooting response. Interaction (clone × IBA) was significant only for production of number
of roots per cutting. Periodic sampling for clone C3 was performed at 0, 7, 14, 21, 28 and 35 days to examine the contents
of total soluble sugars, starch, protein and peroxidase (PER) activity in the rooting zone of cuttings (∼0.5 cm) during adventitious
root primordium development. A significant increase in all the metabolic activities was noted due to IBA. Total soluble sugars
and starch contents of cuttings decreased with the passage of time. Protein content and PER-activity started to increase in
the early stage and reached the highest level on day 21, followed by a decline at the 35th day of sampling. These trends were
common for both IBA treated and untreated cuttings. Protein content and PER-activity remained higher in the rooting zone of
IBA treated cuttings. Overall these findings suggested that exogenous application of IBA may have activated carbohydrate metabolism
for release of energy, while protein and PER-activity were necessary for cell division and differentiation during adventitious
root primordium initiation and development in the rooting zone of cuttings. 相似文献
15.
The main objective of our clonal propagation program is the production of high quality timber and faster tree growth. Teak
(Tectona grandis Linn. f.) is an important plantation species in the tropics but the demand of teak timber is increasing globally. Teak planting
stock is still produced from seeds of unselected elite genotypes which may lead to poor stand establishment. The number of
seeds per fruit and their germination ability are also variable and limited by several factors. Therefore an alternative method
i.e., clonal propagation is required for mass multiplication of elite trees. It is an established fact that the clonal propagation
or adventitious root formation in cuttings is markedly affected by several external and internal factors. Considering these,
an experiment was conducted on leafy soft wood shoot cuttings of 3-year-old hedged teak stock plants grown in a hedge garden
to study the effects of branch position and auxin treatment on adventitious root formation. A factorial completely randomized
design was used for experimentation. Coppice shoots were collected from basal, middle and upper positions of the hedge garden;
and mono-nodal leafy cuttings were prepared. These cuttings were treated with different concentrations of IBA and NAA; and
were cultured in a mist chamber for rooting where the relative humidity was maintained at 85 ± 2% with maximum and minimum
day-night temperature at 32 ± 1°C and 26 ± 1°C respectively. After 45 days the cuttings were removed from the rooting medium
and observations were made. It was observed that the rooting parameters viz., percent rooting and percent sprouting, mean
number of leaves, mean number of shoots and length, and mean number of roots and length per cutting were significantly influenced
by the branch position and auxin treatment. Treatment with 4000 ppm IBA increased percent rooting and percent sprouting whereas
NAA suppressed it. Treatment with 4000 ppm IBA also increased the mean number of leaves and shoots, and the length, and the
mean number of roots per cutting. The highest mean number of roots and length were observed in cuttings taken from the branch
emerging at the upper position followed by branches of middle and lower position. Cuttings of branches at a middle position
showed the highest values of percent rooting, percent sprouting, mean number of leaves and shoots and mean shoot length per
cutting. Furthermore, the interactive effect of branch position and auxin treatment on rooting and sprouting response was
also found to be significant. Overall, the findings of this investigation suggest that middle branch position in hedge plants
and 4000 ppm IBA can be made to induce maximum rooting and to produce high quality planting stock material for clonal forestry
program of teak. 相似文献
16.
骆琴娅 《中南林业科技大学学报(自然科学版)》1991,(2)
用IBA500ppm和1000ppm酒精溶液处理乌桕嫩枝扦插条,能促进插条生根及生长。用500 ppm和1000ppm PP333溶液处理插条,扦插后的前20天表现出对生根有不同程度的抑制作用。但40天时,500 ppm处理的生根率明显增高,1000ppm处理的也出现了愈伤组织,并表明其对根的粗度生长具有促进作用。 相似文献
17.
18.
A study to determine the best vegetative propagation protocol was carried out for Dalbergia melanoxylon. Natural regeneration of D. melanoxylon is limited due to poor seed viability and germination. The effects of age of donor plant, indole-3-butyric acid (IBA) treatment
and cutting position on rooting of stem cuttings were investigated. The effect of age of donor plant was significant (P < 0.001) only for percent rooting, position effect was significant for all studied parameters, and IBA treatment at 300 ppm
was insignificant only for percent callusing. Interactive effects of cutting position × age of donor and cutting position × IBA
treatment were significant for percent rooting and root number per cuttings while interactive effect of age × IBA was significant
only for percent rooting. Observed difference in rooting performance could be due to uneven distribution of root promoting
and inhibiting substances with respect to age of donor plant and IBA which intensified root formation. Cuttings from juvenile
donor plant performed better in all rooting parameters than mature donor plant. The highest percentages in rooting were (71.11%)
and (24.42%) for cuttings from juvenile and mature donor plants, respectively. IBA treated cuttings produced higher percentage
rooting, number of roots and root length than untreated cuttings which revealed a strong IBA influence on rooting ability
of stem cuttings in D. melanoxylon. It was concluded that stem cuttings should be taken from juvenile donor plants and basal cutting position should be used
to produce high quality planting stock material for the afforestation and conservation programme of D. melanoxylon. 相似文献
19.
Many plantation tree species are cloned to achieve the growth, disease resistance and wood quality characteristics required
for a successful economic venture. However, clonal propagation is limited by declines in adventitious root formation with
increasing stock plant age. We examined the effects of immediate or delayed IBA application on adventitious root formation
and subsequent root and shoot development of cuttings harvested from 8-year-old clonal hedge plants of Pinus elliottii var. elliottii × P. caribaea var. hondurensis. IBA applied at the time of setting accelerated root formation, elevating the percentage of cuttings with roots at 13 weeks
post-setting from 45 to 78% and from 83 to 93% for a low- and a high-rooting clone, respectively. Final rooting percentages
for the same treatments and clones (78 and 85%, and 88 and 100%, respectively, at 20 weeks post-setting) were not significantly
affected by IBA application. IBA increased the root:shoot ratio of rooted cuttings by decreasing shoot weight compared with
untreated cuttings, without affecting root weight, root length, root surface area or root volume. IBA was only effective when
applied at the time of setting. A simple IBA treatment for cuttings from 8-year-old clonal hedges, by accelerating root production,
has potential for reducing nursery costs and increasing the root system quality of containerised pine cuttings. 相似文献
20.
Agnes Gachuiri Catherine Muthuri Jonathan K. Muriuki Ramni H. Jamnadass Fergus Sinclair 《林业研究》2016,27(1):59-66
The variation in shoot and root seedling growth traits was compared among three Faidherbia albida(Del).A. Chev. provenances originating from Kenya(Taveta),Malawi(Bolero) and Ghana(Bolgatanga); representing east, south and west Africa, respectively. Bulked seeds from three provenances were grown in two soil types(clay and sand) at the World Agroforestry Centre nursery,Nairobi. Seedlings grown in clay soil had high shoot growth and shoot to root ratios but shorter root length,lower number of nodules and specific root length compared to seedlings in sand soil. Shoot to root ratios reduced with time and this was more pronounced in sand soil. Overall,the Bolero and Taveta provenances had higher growth than the Bolgatanga provenance. This was probably because plants grown in nutrient-rich clay soil invest more in shoot growth as compared to root growth. Longer root growth in sand soil shows a better adaptive mechanism that increases competitive ability and survival in nutrient-poor systems.Variations observed among the seedling variables such us shoot and root growth could be used for early selection for reforestation and agroforestry in predominantly clay and sand soil areas. 相似文献