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1.
A nursery experiment was conducted in un-sterilized soil in Senegal using six Calliandra species or provenances inoculated with a mixture of seven rhizobial strains. Plant growth was assessed periodically at 1,
2, 3, 12 and 18 months whereas nodulation, shoot and root dry weights were assessed at 12 and 18 months after planting (MAP).
Un-inoculated seedlings of all the six species died at 12 months after planting. Results of growth assessments were variable
with significant differences (P < 0.05) between C. calothyrsus Meissn provenances (Flores and San Ramón) and C. juzepczukii Standley in height at 1, 2 and 3 MAP. Shoot dry weights of San Ramón provenance of C. calothyrsus Meissn were also significantly different from those of C. acapulcensis (Britton and Rose) Standley and C. longepedicellata (Mc Vaugh) H. Hern and Macqueen at 18 MAP. In contrast, C. glandiflora (L’Her.) Benth grew poorly and did not nodulate. Although rhizobial inoculation improved shoot and root dry weights some
differences were observed among the Calliandra species in response to the inoculation, which suggested the occurrence of interaction between the rhizobial strains and the
host plant species tested. 相似文献
2.
A protocol was developed for shoot proliferation and plantlet formation of Khaya senegalensis, an important medicinal and timber plantation species introduced to Australia and southern Asia from western and central
Africa. We assessed effects of the plant growth regulators, benzyladenine, kinetin, naphthalene acetic acid and gibberellic
acid, on shoot proliferation and subsequent plantlet conversion. Shoot proliferation over four passages was higher in media
containing benzyladenine than in media containing other growth regulators, and optimal proliferation from seed of three different
sources was consistently obtained in medium containing 4.4 μM benzyladenine. Shoots from this medium were converted to plantlets
at high frequencies (76–90%) after treatment with 19.6 μM indole-3-butyric acid, and almost all plantlets were successfully
acclimatized to nursery conditions. These methods provide the means for establishing in vitro and ex vitro clone banks of
juvenile K. senegalensis trees for field selection of desired genotypes and tropical plantation establishment. 相似文献
3.
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
4.
Biodiversity of arbuscular mycorrhizal (AM) colonization and AM fungal spores were studied in the roots and rhizosphere soils of Acacia catechu (L.f). Wild., A. mangium Willd, Anthocephala cadamba Miq., Artocarpus chaplasha Roxb., Chickrassia tabularis A. Juss., Swietenia macrophylla King., Tectona grandis L. from plantations; Albizia procera (Roxb.) Benth., A. falcataria L., Alstonia scholaris (L.) R. Br., Aphanamixis polystachya (Wall.) Parker., Hydnocarpus kurzii (King.) Warb., Heynea trijuga Roxb., Lagerstroemia speciosa (L.) Pers., Messua ferrea Linn., Podocarpus nerifolia Don., Swintonia floribunda Griff., Syzygium fruticosum (Roxb.) DC., S. grandis (Wt.) Wal. from forest and nursery seedlings of A. polystachya, A. chaplasha, Gmelina arborea Roxb. and S. cuminii (L.) Skeels from Hazarikhil forest, Chittagong of Bangladesh. Roots were stained in aniline blue and rhizosphere soils were assessed by wet sieving and decanting methods. The range of AM colonization varied significantly from 10%-73% in the plantations samples. Maximum colonization was observed in A. mangium (73%) and minimum colonization was observed in C. tabularis (10%). Vesicular colonization was recorded 15%-67% in five plantation tree species. The highest was in A. cadamba (67%) and the lowest was in T. grandis; A. chaplasha and C. tabularis showed no vesicular colonization. Arbuscular colonization was recorded 12%-60% in four plantation tree species. The highest was in A. mangium (60%) and the lowest was in A. cadamba. Roots of Artocarpus chaplasha, C. tabularis and T. grandis showed no arbuscular colonization. Among 12 forest tree species, nine tree species showed AM colonization. The highest was in A. falcataria (62%) and the lowest was in S. fruticosum (10%). Significant variation in vesicular colonization was recorded in seven forest tree species. The highest was in H. trijuga (52%) and the lowest was in L. speciosa (18%). Hydnocarpus kurzii, M. ferrea, P. nerifolia S. fruticosum and S. grandis showed no vesicular colonization. Arbuscular colonization was recorded in seven forest tree species. The highest was in A. falcataria (60%) and the lowest was in A. procera (10%). All the nursery seedlings showed AM colonization and the range was 10%-73%. Vesicules were recorded in G. arborea (40%) and S. cumini (40%). Arbuscular colonization was recorded in G. arborea (100%) and S. cumini (100%). Spore population was recorded 77-432/100 g dry soils, 80-276/100 g dry soils, and 75-153/100g dry soils in plantation, forest and nursery, respectively. Glomus and Acaulospora were dominant genera among the six AM fungi recorded. Significantly positive correlation was observed between AM colonization and AM fungal spore population in Hazarikhil plantation tree species, forest tree species and nursery tree seedlings. The present study showed the biodiversity of root colonization and AM fungi are active in nutrient cycling, survivals and seedling establishment of the plants in the Hazarikhil forest, plantation and nursery. 相似文献
5.
Juan A. Oliet María Tejada K. Francis Salifu Aleyda Collazos Douglass F. Jacobs 《European Journal of Forest Research》2009,128(3):253-263
Holm oak (Quercus ilex L.) seedlings were exponentially (E) nutrient loaded using incremental increases in fertilizer addition or conventionally
(C) fertilized using a constant fertilizer rate during nursery culture. The fertility treatments (mg N plant−1) were control (0), 25E, 100E, and 100C. Subsequently, 1-year-old plants were transplanted under simulated soil fertility
gradients in a greenhouse to evaluate effects of nutrient loading and post-transplant fertility on seedling performance. Post-transplant
fertility consisted of fertilizing plants at two rates (0 vs. 200 mg N plant−1). A water-soluble fertilizer 20-20-20 was supplied in both nursery and post-transplant experiments. Nutrient loading increased
plant N content by 73% in 100E and by 75% in 100C relative to controls, although no significant differences were detected
between constant and exponential fertilization regimes at the 100 mg N plant−1 rate. When transplanted, nutrient loading promoted post-transplant root growth relative to shoot, implicating potential to
confer competitive advantage to loaded holm oak seedlings after trans-planting. In contrast, post-transplant fertility increased
new shoot dry mass by 140% as well as N, P and K content relative to controls. Results suggest that holm oak seedlings can
be successfully nutrient loaded in the nursery at higher fertility rates, improving its potential to extend new roots, but
alternative fertilization regimes and schedules that better fit nutrient availability to the growth rhythm and conservative
strategy of this species must be tested. 相似文献
6.
The effects of the arbuscular mycorrhizal (AM) fungus Glomus mosseae on plant growth, leaf solutes and root absorption area of trifoliate orange (Poncirus trifoliata (L.) Raf.) seedlings were studied in potted culture under water stress conditions. Inoculation with G. mosseae increased plant height, stem diameter, leaf area, shoot dry weight, root dry weight and plant dry weight, when the soil water
content was 20%, 16% and 12%. AM inoculation also promoted the active and total absorption area of root system and absorption
of phosphorus from the rhizosphere, enhanced the content of soluble sugar in leaves and roots, and reduced proline content
in leaves. AM seedings had higher plant water use efficiency and higher drought tolerance than non-AM seedlings. Effects of
G. mosseae inoculation on trifoliate orange seedlings under 20% and 16% soil water content were more significant than under 12% soil
water content. AM infection was severely restrained by 12% soil water content. Thus, effects of AM fungi on plants were probably
positively related to the extent of root colonization by AM fungi. The mechanism of AM fungi in enhancing drought resistance
of host plants ascribed to greater osmotic adjustment and greater absorption area of root system by AM colonization.
__________
Translated from Journal of Plant Physiology and Molecular Biology, 2005, 30(5): 583–588 [译自: 植物生理与分子生物学报, 2005, 30(5): 583–588] 相似文献
7.
《Scandinavian Journal of Forest Research》2012,27(1-4):397-402
Six provenances of both Pseudotsuga menziesii (Mirb.) Franco and Pinus contorta Dougl. from a range of locations in the interior of British Columbia between latitudes 49° and 58° were grown for 80 days in controlled environment chambers programmed to provide daylengths comparable with those at either latitude 48°, or latitude 58°, during the period from mid‐June to early September. Neither shoot : root ratio nor whole plant dry weight of P. menziesii were affected by photoperiod. However, P. contorta seedlings, which unlike P. menziesii set bud during the experiment, had a greater dry weight and a higher shoot:root ratio (p<0.05) under longer daylengths. The results appear relevant to the interpretation of effects of cross‐latitudinal provenance transfer on plantation productivity. 相似文献
8.
S. M. S. Huda M. Sujauddin S. Shafinat M. S. Uddin 《林业研究》2007,18(4):279-282
A study was conducted to test the influence of different inorganic fertilizers (phosphorous and potassium) on the nodulation and growth of Dalbergia sissoo grown in the nursery. Before seeds sowing, different combinations of P, K fertilizers were incorporated with the nutrient-deficient natural forest soils, and then amended with cowdung (soil: cowdung = 3:1). Nodulation status (nodule number, shape, fresh weight, dry weight and color) in the roots and the plant growth parameters (length of shoot and root, collar diameter, fresh and dry weight of shoot and root) were recorded 60 days after seeds sowing. Nodulation status and growth of the plants varied significantly (P〈0.05) in the soils amended with fertilizers in comparison to the control. The highest nodule number (62), fresh (0.50 g) and dry (0.07 g) weights were recorded with the dose of PK at the rate of 160 kg/hm2. Nodule shape and color also varied widely in different treatments. In case of plant growth parameters, shoot and root length, collar diameter, fresh and dry weight of the plants took on a significant difference (P〈0.05) among various combination of fertilizers. From the study, it is revealed that PK at the rate of 160 kg/hm^2 fertilizer with soil and cowdung mixture (soil: eowdung = 3:1) is recommended for optimum growth and nodule formation of D. sissoo in degraded soils at a nursery level. 相似文献
9.
The effects of propagation medium and the type of auxin on root and shoot development of stem cuttings of Calliandra calothyrsus
were investigated in two experiments. Cuttings were taken from four-week-old coppice shoots from a cleared C. calothyrsus
plantation. In Experiment 1, the effects of five propagation media; fine sand (FS) (3 mm), sawdust (SD), fine gravel (FG)
(6 mm) and 50:50 mixtures of FS:SD and FG:SD were compared. In Experiment 2, two commercial brands of auxin rooting powder
– ‘Seradix 3’ (IBA) and ‘Bouture CF’ (NAA, IBA and MNAA) were evaluated. The experiments were done in a low-cost, non-mist
propagator system in Cameroon. Propagation medium had a significant (P = 0.05) effect on mean rooting percentage (FS = 43%
and FS:SD = 93%). The effect of the media on shoot growth from the cuttings (height, basal diameter and root biomass) were
also significant (P = 0.05). The application of both the commercial brands of auxin significantly enhanced rooting (84% for
untreated cuttings and 91% for IBA- treated cuttings). Bouture CF promoted shoot development from the cuttings, while Seradix
3 inhibited shoot development. The results indicate that in the humid lowlands of Cameroon, where seed productivity of C.
calothyrsus is known to be very poor, large-scale production of young plants using these techniques is possible.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
Soil hydro-physical behaviour was studied under a 20-year old agroforestry plantation consisting of five multipurpose tree
species (Pinus kesiya Royle ex-Gordon, Alnus nepalensis D.Don, Parkia roxburghii G.Don, Michelia oblonga Wall. and Gmelina arboria Roxb.) maintained under normal recommended practices at Indian Council of Agricultural Research (ICAR) Complex, Umiam, Meghalaya,
India. The aim was to select tree species, which could act as better bio-ameliorant as well as provides higher economic return
in highly degraded soil of northeastern hill region of India. A site without vegetation (no tree) nearby the plantation was
also selected as control for comparison. Soil samples for various hydro-physical analysis, were taken from 0–15 and 15–30 cm
soil depth at a distance of 1 m from respective tree species during wet and dry season of 2003–2004. No appreciable differences
in relative contents of textural separates of sand, silt and clay were observed among various tree covers. Surface cover with
constant leaf litter fall and extensive root system increased soil organic carbon, helped in better soil aggregation, improved
water transmissivity and infiltrability and in turn, reduced soil erosion in the present study. However, due to variation
in quantity of leaf litter fall and root biomass, these parameters differed among tree species. Of the tree species, P. kesiya, M. oblonga and A. nepalensis were found to be rated best for bio-amelioration of soils as these tree covers had more root and shoot biomass and more litter
fall compared to other species. However, considering both timber production and improvement in hydro-physical behaviour, M. oblonga was found best among the tested tree species. The study, thus, suggested that inclusion of tree species M. oblonga in agroforestry system is a viable option for natural resource management and could sustain long-term soil productivity in
a highly degraded soil of this region as well as for food security of the resource poor people of North East India. 相似文献
11.
Li Shan-wen Zhang Zhiyi He Cheng-zhong An Xin-min Yu Zhi-shui Li Bai-lian 《中国林学(英文版)》2005,7(3):61-69
Twenty-five species and hybrids in Populus were used as parents, and 26 cross combinations, including more than 5 000 seedlings, were obtained by artificial cross breeding.
The length of infructescence, number of seeds per infructescence, thousand-seed weight, germination rate of seeds among these
cross combinations were tested. The results indicated that the cross combinational effects were significant for these traits,
and demonstrated that the length of infructescence, thousand-seed weight were positively affected by female parent. In addition,
seedling height, diameter above ground, diameter at breast height (DBH) of 17 cross combination progenies were investigated.
The analysis of mean and standard deviation of these three traits showed that seedling height, diameter above ground, DBH
had extensive variation among combinations and individuals within combination. Variance analysis and estimate of heritability
indicated that the three traits had wide variation and were controlled by heredity. It was feasible to select superior cross
combinations and seedlings. Further more, the result of multiple comparison showed that P. deltoides ‘Lux’ × P. deltoides ‘D324’, P. ussuriensis cl. ‘U4’ × P. deltoides ‘T66’, P. ussuriensis cl. ‘U4’ × P. deltoides ‘T26’, P. deltoides ‘Lux’ × P. ussuriensis cl. ‘U3’, (P. tomentosa × P. bolleana) × (P. alba × P. glandulosa), (P. alba × P. tomentosa) × (P. alba × P. glandulosa), and (P. alba × P. glandulosa ‘No. 2’) × P. tomentosa ‘Lumao 50’ were superior cross combinations with higher growth rate. Finally, 123 elite seedlings were selected for further
test.
[Supported by the Doctoral Foundation of Ministry of Education (Grant No. 200220022004) and the National “863” Project (Grant
No. 2002AA241071)] 相似文献
12.
The effect of seed source (half-sib family) and nursery bed density on the nursery stock quality and subsequent growth of
black walnut (Juglans nigra L.) was investigated. Nine black walnut female genitors were selected to represent a range of phenotypes. Seeds were collected,
cleaned, cold-treated, and pre-sprouted to ensure that germination was uniform and complete. The pre-sprouted seeds were planted
in a randomized complete block design into standard nursery beds in Indiana, USA at three sowing densities, (11.2 plants m−2; 24.2 plants m−2; 29.4 plants m−2). After lifting, the trees were measured for height, ground-line diameter and root volume and then planted into a plantation
in a randomized complete block design and re-measured after 1 and 5 years of growth. One year after planting, the effects
of family (half-sib seed source) and density were significant or very highly significant for seedling height, and ground-line
diameter, although family effects were greater than those for density, especially at moderate and high nursery bed density.
After 5 years of growth, the same effects contributed significantly to ground-line diameter and dbh, but only family significantly
influenced height. Family was more important than nursery bed density in determining the size of the trees after 5 years.
Although there were no significant family × density interactions after 5 years, family variance for all the traits was considerably
higher among seedlings grown at moderate and high density in the nursery. Phenotypic correlations among traits within and
among years were generally very high (0.65 < r < 0.90) and insensitive to planting density in the nursery. 相似文献
13.
CANNELL M. G. R.; TABBUSH P. M.; DEANS J. D.; HOLLINGSWORTH M. K.; SHEPPARD L. J.; PHILIPSON J. J.; MURRAY M. B. 《Forestry》1990,63(1):9-27
Seedlings (transplants) of 2+1 Sitka spruce (Picea sitchensis(Bong.) Carr.) and 1 + 1 Douglas fir (Pseudotsuga menziesii(Mirb.) Franco) were grown in a nursery at the Bush Estate,Scotland. Batches were lifted and cold stored at 0.5°C inNovember, December and January. Changes in growth, shoot apicalmitotic index, root growth potential (RGP), carbohydrate content,bud dormancy and shoot frost hardiness were monitored throughoutthe winter by taking samples at intervals from the nursery andfrom cold storage. Frost hardening occurred during the later stages of bud development(as mitotic indices decreased); autumn hardening was arrestedwhen seedlings were put in cold store, and some dehardeningoccurred in cold storage, especially in spring. Bud dormancystarted, and was greatest, just after bud growth (mitotic activity)virtually ceased; chilling in cold store was almost as effectivein releasing dormancy as natural chilling. The concentrationof total nonstructural carbohydrates stayed more or less constantat 100150mg g1 from September to April in thenursery; in cold storage carbohydrates were depleted at 0.40.6mgg1 d1 (corresponding to respiration at 0.030.05mgCO2 g1 h1) until there was only 4050mgg1. Root growth potentials in the nursery increased in December,once the buds ceased growth, became dormant and had receivedsome chilling. Sitka spruce was storable in November,before RGPs increased, but they then failed to achieve maximalfrost hardiness or ROP. Winter RGPs were high in Sitka spruceand were increased or maintained in cold storage, whereas RGPswere low in Douglas fir and decreased immediately after storage(except when stored in January). By the end of April, the RGPof cold stored Sitka spruce was much higher than that of directlifted plants. ROP changes in the nursery and in cold storagewere not consistently related to changes in seedling carbohydratecontents, shoot frost hardiness or bud dormancy. In practical terms, it was concluded that (1) the optimum dateto start lifting bare- rooted conifer transplants in the autumnis when their shoot apical mitotic indices have decreased tonear zero, and their RGPs have risen sharply; (2) high RGPsmay depend as much on the morphology of the roots (e.g. numberof undamaged root apices) as on the physiology of the shoots(e.g. carbohydrate status, dormancy and frost hardiness); and(3) in spring, transplants kept in cold storage since November,December or January are more frost hardy, slightly more dormant,and (in May) have higher RGPs than transplants lifted from thenursery. 相似文献
14.
The germination of common alder (Alnus glutinosa (L.) Gaertn.) and downey birch (Betula pubescens Ehrh.) seeds is often poor in bare-root nurseries. The effect of a variety of seed coverings and a few seed pretreatments
on seedling emergence was examined in this study in an attempt to address this problem. Seeds of each species were sown in
trays containing nursery soil, covered with grit, gravel, sand, combinations of these coverings, a hydromulch or a sealed
plastic cloche and then incubated for 6 weeks at 17–20°C. The grit combined with sand or gravel, the hydromulch and the cloche
increased seedling emergence when compared with the standard grit. In another experiment, seeds of each species were fully
imbibed (FI) (>50% moisture content, MC), as per standard practice, or adjusted to target MC (TMC) (30–35% MC) levels, and
then chilled to release dormancy. Some seeds of each MC treatment were primed at 20°C for 2 days following chilling, after
which all seeds were evaluated in laboratory tests and a nursery trial. Germination potential of the FI seeds declined in
the lab tests by the second test date, which was reflected in low seedling emergence in the nursery in birch. The primed FI
seeds of alder germinated most rapidly in the nursery, but other effects were not significant. Seedling emergence was better
in the nursery in response to the TMC than the FI pretreatment in birch.
相似文献
Conor O’ReillyEmail: |
15.
Because lack of data impedes the assessment of the conservation of medicinal plants, ethno-medicinal studies are important
to fill this gap. This study considered the traditional use of plants for health care by the rural communities in two forested
and non-forested regions of Bangladesh. A total of 230 respondents were interviewed accompanied by field observation and voucher
specimen collection. Altogether, 68 species of medicinal plants belonging to 38 families distributing over 58 genera were
recorded, of which 22 species were common in both regions. Trees were the most commonly utilized growth form and leaves were
the most commonly used plant part. Forests and homesteads were the major sources of medicinal plants in forested and non-forested
regions, respectively. High use versatility (Relative Importance >1) was represented by 14 species; Emblica officinale L. and Allium sativum L. were the most versatile species. Forty-one individual ailments were treated with the medicinal plants recorded. The ailment
categories ‘respiratory problems’ and ‘sexual problems’ received the highest score from the calculation of informants’ consensus
factor (F
ic) in forested and non-forested regions, respectively. The findings could contribute in the pharmaceutical sector by directing
further investigation of bio-active compounds in medicinal plants. Secondly, results could inform the clues for conservation
strategies of forest resources in that region. 相似文献
16.
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
17.
E. Chirino A. Vilagrosa E.I. Hernndez A. Matos V.R. Vallejo 《Forest Ecology and Management》2008,256(4):779-785
In the last decades, reforestation and afforestation programs are being carried out mainly with containerized seedlings. Container design determines the morphological and physiological characteristics of seedlings. However, container characteristics are often the same for plant species with very different growth strategies. The most commonly used nursery containers are relatively shallow and limit tap root growth; consequently, species relying on the early development of a long tap root to escape drought, such as those of the Quercus genus, might need to be cultivated in deep containers. The aim of this paper was to compare the morphological and physiological characteristics of Quercus suber L. seedlings cultivated in shallow containers (CCS-18, depth 18 cm) with seedlings cultivated in deep containers (CCL-30, depth 30 cm). Both container types used were made of high-density polyethylene, cylindrical in shape, open-bottomed, with a diameter of 5 cm, two kinds of vertical ribs on the inside wall showing a cultivation density of 318 seedlings/m2. At the end of nursery culture, the seedlings cultivated in the CCL-30 deep container presented a longer tap root, higher shoot and root biomass and higher Dickson Quality Index (DQI). Moreover, the CCL-30 seedlings showed a higher root growth capacity (RGC), they reached deep substrate layers faster and they presented higher root hydraulic conductance. These morpho-functional advantages improved the CCL-30 seedling water status, which was expressed by higher stomatal conductance during an imposed drought period. 相似文献
18.
Under artificially-simulated complex salt-alkali stress, the levels of active oxygen metabolism in roots were studied using three-year-old cutting seedlings of Spiraea × bumalda ’Gold Mound’ and Spiraea × bumalda ’Gold Flame’. The present study aimed at exploring the antioxidant capacity in roots of spiraeas and revealing their adaptability to salt-alkali stress. Results indicate that the oxygen free radicals contents, electrolyte leakage rates and MDA contents in roots of Spiraea × bumalda ’Gold Mound’ and Spiraea × bumalda ’Gold Flame’ show an increasing tendency with the increases of the salinity and pH value, whereas the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) all increased firstly and then decreased. With the increase in intensity of salt-alkali stress, the CAT activity in roots of Spiraea × bumalda ’Gold Flame’ is higher and the increasing extents in the oxygen free radicals contents, electrolyte leakage rates as well as MDA contents are lower compared with Spiraea × bumalda ’Gold Mound’, indicating that Spiraea × bumalda ’Gold Flame’ has a stronger antioxidant capacity. 相似文献
19.
Ebenezar Asaah Zac Tchoundjeu William Ngahane Alain Tsobeng Lazare Kouodiekong Ramni Jamnadass Anthony Simons 《New Forests》2011,41(3):389-398
Three Allanblackia species (A. floribunda, A. stuhlmannii and A. parviflora) with high nutritive, medicinal, cosmetic and economic values are currently being domesticated as new oil tree crops. Allanblackia seeds contain a hard white fat consisting mostly of stearic (52–58%) and oleic (39–49%) acids. This unusual fatty acid content
has the right properties for many different food and cosmetic products making them commercially interesting. Vegetative propagation
studies on A. floribunda, which grows naturally in the moist forest of Cameroon and Nigeria, were initiated aimed at evaluating its amenability to
grafting. Scions were grafted onto 18 month old rootstocks of A. floribunda using side tongue, top cleft, side veneer, whip-and-tongue methods under nursery conditions in Cameroon. In parallel, side
tongue and inverted ‘T’ budding methods were also tested in situ on young A. floribunda wildings growing under semi-deciduous and evergreen tree covers. In addition, the effects of protecting side tongue new grafts
with non perforated translucent plastic, perforated translucent plastic and aluminium foil were assessed. Under nursery conditions,
side tongue grafts were significantly more successful (80.0 ± 6.3%), than grafts of side veneer (52.5 ± 7.9%), top cleft (55.0 ± 7.9%)
and whip and tongue (50.0 ± 7.9%). The success of side tongue graft was further increased (86.7 ± 6.2%) under the shade of
evergreen trees when protected by non perforated translucent plastic. These results indicate the potential for in situ grafting
and ‘top working’ to promote cultivation of more productive germplasm of Allanblackia within multifunctional agricultural systems. 相似文献
20.
Gerhard Langenberger Vanessa Prigge Konrad Martin Beatriz Belonias Joachim Sauerborn 《Agroforestry Systems》2009,76(1):173-194
Complex agroforestry systems that mimic local forest structure, so-called ‘analogs’, are assumed to be of specific value to
rural people as well as the environment. The objective of this study was to document and evaluate the utilization of plant
resources by Philippine lowland farmers to identify native species suitable for integration in such a system. The interviewed
farmers maintain a comprehensive ethnobotanical knowledge. They reported using 122 plant species for 77 purposes. Eighty species
have medicinal value, 35 provide food, and 32 serve other uses. About 64% of the identified species are Philippine natives.
The life form composition of these species is dominated by trees but also includes herbs, lianas, and graminoids, thus providing
the structural elements required in analog systems. Nevertheless, only a few of the species seem to be promising for cultivation.
Many of them are ubiquitous in the vicinity of villages. Some species are also not much appreciated but act as staple food
only during food shortage. Even though several of the species have proven market value, such as rattan (e.g. Calamus
merrillii), or are reputed medicines, such as ‘Philippine ginseng’ (Sarcandra glabra), no cultivation could be observed. This shows that usefulness in itself cannot be the only criterion to promote species
but that it requires a careful analysis of the marketability of the respective species. In this context we suggest the following
three species that are of proven medicinal value for in-depth study: the liana Tinospora crispa (Menispermaceae), the tree Picrasma javanica (Simaroubaceae), and the herb Sarcandra glabra (Chloranthaceae). They represent three different life form strategies and would thus fit well in vertically structured agroforestry
systems. 相似文献