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1.
Many interspecific hybrids have been produced among Leucaena species, some with great potential for high-value wood and forage production. Superior hybrids are often highly sterile,
and vegetative propagation would be essential for their exploitation. Four experiments were conducted to investigate factors
affecting the rooting of cuttings of Leucaena hybrids. Nine hybrids were studied that represented different ploidy levels (2x, 3x, and 4x), different levels of seedlessness,
different ages (5–16 years) and varying leaflet sizes. Rooting ability basically depended on genotype, with only a few hybrids
failing to root. Cuttings required leaflets to root, and half or more of a leaf led to higher frequencies of better roots.
One-node cuttings had the same rooting ability as two-node cuttings. Rooting ability decreased dramatically in the cooler,
low-light winter seasons of lowland Hawaii. Etiolation treatments increased rooting ability significantly for two difficult-to-root
hybrids. 相似文献
2.
Leaf area, IBA concentration and age of stockplants were all found to be important factors for successful rooting for vegetative
propagation using single-node cuttings of the two main African mahogany species: Khaya anthotheca and K. ivorensis. Cuttings with leaf area of 30–50 cm2 had the best rooting percentage and cuttings with about 30 cm2 had the most number of roots per cutting in K. anthotheca. Khaya ivorensis, cuttings with 10–30 cm2 leaf area had the highest rooting percentage. Cuttings collected from 1-year-old stockplants recorded the highest rooting
percentage and largest number of roots per cutting. Cuttings from 3-year-old stockplant of the same seeds sources had the
lowest rooting suggesting aging negatively impacted rooting ability. The effect of auxin concentration, on rootability was
examined with cuttings of K. anthotheca. An IBA concentration of 0.8% was the best exogenous auxin concentration for percentage rooting, number of roots per cutting
and the length of the longest root per cutting. 相似文献
3.
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
4.
Techniques for the vegetative propagation of Ulmus villosa, an indigenous agroforestry tree species of the north-western sub-Himalayas, were developed. Studies investigated the effects on rooting of stem cuttings of growth regulators with sucrose and fungicide (0%, 0.2% p-HBA + 5% sucrose + 5% captan, and IBA concentrations ranging from 0.2 to 1.0% plus each containing, 0.2% p-HBA + 5% sucrose + 5% captan). Cuttings were collected at two times of the year (February and July) from two types of stock plant (seedling and mature trees) and from two positions within the shoots (lower and upper nodes). Cuttings collected in February were leafless, while those collected in July had about 80 cm2 leaf areas. These cuttings were then set under a mist unit. Percentage rooting and primary root number differed significantly between treated and untreated cuttings. Treatment of cuttings with chemical formulations of 0.4% IBA + 0.2% p-HBA + 5% sucrose + 5% captan maximized rooting (82.0%), while, survival (80%) and primary root number (14.7) were greatest with: (i) 0.6% IBA + 0.2% p-HBA + 5% sucrose + 5% captain and (ii) 0.8% IBA + 0.2% p-HBA + 5% sucrose + 5% captan, respectively. Rooting success and root number were better in propagules set in February rather than in July. Cuttings from seedlings rooted better, with more roots ensuring better survival, than cuttings from mature trees (12–13-years-old). In cuttings from seedlings, those cuttings collected from the lower part of the shoots had greater percentage rooting and primary root number than those from the upper part. Maximum root regeneration (100%), roots number (19.0), and survival (98.5%) were achieved when the time of collection (February) and shoot position were optimized. Rooting was best when cuttings had higher levels of sugar, total carbohydrate and peroxidase enzyme activity, and low N. 相似文献
5.
Celastrus paniculatus Willd. (Celastraceae) is an important medicinal tree valued for its seeds. Indiscriminate collection of this plant from the
habitat zones has posed a serious threat to its existence in the wild, results in globally a threatened plant species. Ex
situ conservation is a prioritized agenda of research for redlisted plant species. Semi-hardwood stem cuttings collected from
10 to 15 year old trees were treated with different concentrations (0, 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 g l−1) of growth hormones; indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and 1-naphthalene acetic acid (NAA) for positive
effect on root induction. After 90 days of treatment, results were analyzed for percentage of rooting, root number and average
root length per rooted cuttings. The highest rooting (57%) response with highest number of roots (~77.2) was obtained in indole-3-acetic
acid at 3.0 g l−1. Overall, high significant (P ≤ 0.05) rooting response was noticed in IAA treatment comparative to hormones IBA and NAA. Rooted cuttings exhibited 100%
survival in the experimental field. This study reveals the propagation of semi-hardwood cuttings derived from partially matured
branches is possible and it provides a basis for conservation of this threatened plant species by reducing pressure on its
natural populations. 相似文献
6.
A 5-year stand of teak (Tectona grandis L. f.) was coppiced in 1999 and converted into a vegetative multiplication garden. Subsequently, three harvesting regimes
for the collection of single node stem cuttings were imposed: (1) once – in March (H1), (2) twice – in March and September (H2) and (3) three times in March, July and November (H3). Cuttings were treated basally with either:- T0 – control (6 h in water), T1 – half the recommended dose of a mixture of IBA and thiamine (500 ppm IBA + 400 ppm thiamine) or T2 – the full dose of the same mixture (1000 ppm IBA + 800 ppm thiamine). Cuttings receiving IBA + thiamine rooted significantly
better than untreated cuttings, but even the best treatment only resulted in 38.3 ± 3.8% rooting. This treatment produced
the greatest number of roots (5.2–12.1). The full dose treatment appears to have been supra-optimal. Rooting ability was also
affected by the frequency of stockplant pruning, with cuttings from stockplants pruned twice per year having the greatest
rooting percentage (27.8 ± 3.8%) and the most roots (9.2 ± 4.8). This bi-annual pruning (H2) resulted in the greatest number of rooted propagules (2.6 and 4.2 times more than H1 and H3, respectively). There was a significant interaction between Treatment × Pruning frequency. Bi-annual hedging of teak stockplants
is recommended for practical purposes, although further work is required to achieve commercially acceptable levels of rooting
from coppiced tree stumps. 相似文献
7.
High-quality black walnut (Juglans nigra L.) logs are of great economic value and are used in the manufacture of high-end products. Indigenous to the central hardwood region, black walnut has been commercially cultivated for many years, and genetic improvement and selections have resulted in superior timber genotypes. The recalcitrance of black walnut cuttings to form adventitious roots is the greatest hurdle for mass propagation of improved material. The goal of this research was to improve the frequency of adventitious root formation in black walnut cuttings, and investigate anatomical changes during root development. Softwood cuttings (15–20 cm) were collected from juvenile and mature sources of elite genotypes, dipped for 60 s in 31.1, 62.2, or 93.2 mM indole-3-butyric acid-potassium salt (K-IBA), or 36.9, 73.8, or 110.7 mM indole-3-butyric acid (IBA), and then inserted into a moist medium consisting of 3 perlite: 1 coarse vermiculite (v/v). Cuttings were placed in bench-top fog chambers or a mist bench for 5 weeks. To visualize anatomical changes during root formation, stems were fixed in formaldehyde, embedded in paraffin, serially sectioned, and stained on sequential days throughout root development. Rooting was greatest (72%) for cuttings exposed to 93.2 mM K-IBA and placed in the fog chamber, while cuttings treated with IBA rooted at lower frequencies (16–22.2%). Cuttings in the mist bench often deteriorated and rooted at lower frequencies independent of the auxin type. Anatomical analysis revealed adventitious root initials by day 16 and root primordia formation by day 18. Rooted cuttings survived acclimatization to the greenhouse. 相似文献
8.
在全光下应用双长臂旋转扫描喷雾装置进行水曲柳(Fraxinusmandshurica)扦插试验,通过对插穗的母树年龄、伐根萌条的枝条部位、切口形状、ABT生根粉配置浓度等指标的研究,结果显示,从10、15年生树冠上剪取1、2、3年生枝条,40年生树冠上剪取2、3年生枝条,40年生伐根上剪取1年生枝条做插穗,对生根率的影响差异达到了极显著水平,按生根率高低排序:伐根当年萌生枝条84.76%>10年树的1年枝条82.5%>15年生树的1年枝条79.68%>10年生树的2年枝条56.21%>15年生树的2年枝条55.63%>10年生树3年枝条52.46%>15年生树3年枝条50.62%>40年生树冠的2年生枝条48.36%>40年生树冠的3年生枝条45.59%,切口形状、ABT生根粉浓度和浸泡插穗基部时间对生根率的影响差异极显著,插穗以斜切口,ABT生根粉浓度用质量分数为2.0×10-4的溶液,浸泡插穗基部根时间以4 h为最佳组合,平均生根率为84.76%,最高为93.14%,伐根萌生枝条部位对生根率的影响差异不显著。 相似文献
9.
E. Shibata 《Journal of Forest Research》2003,8(2):0123-0126
To establish a sampling procedure for estimating the density of bamboo galls induced by Aiolomorphus rhopaloides Walker (Hymenoptera: Eurytomidae) in a stand of bamboo Phyllostachys heterocycla (Carr. Mitf.) (Monocotyledoneae: Gramineae), 5–12 bamboo culms were cut at random in late March of each year during 1998–2001
just before gall-maker emergence. The number of galls on the branches of each bamboo culm was counted. The spatial patterns
of the galls on the culms in the stand and on the branches within each culm were measured by Iwao's patchiness regression.
Galls were distributed contagiously both on culms and on branches. Current bamboo culms that emerged the previous summer did
not require sampling because no galls were observed on them. Except for this, there was no difference in gall density on young
and old culms, suggesting that it is not necessary to distinguish them. There were few (<4%) galls above 6 m height during
the 4 years. There was no significant difference in gall density up to 4 m and above 4 m, suggesting that branches up to 4 m
can be sampled with confidence. Kuno's two-stage sampling method at different precision levels showed that the number of culms
to be sampled varied with gall density. For example, at mean density m = 1.0 per branch when the number of sampled branches per culm is 10, a total of 24 culms is required to estimate gall number
at a precision level of D = 0.2, where D is the ratio of standard error to mean.
Received: July 10, 2002 / Accepted: November 25, 2002
Acknowledgments I thank Dr. K. Kamijo for insect identification. Thanks are also due to the members of the Laboratory of Forest Protection
for their kind help with the fieldwork. This study was supported in part by a Grant-in-Aid for Scientific Research (No. 11460068)
from the Ministry of Education, Culture, Sports, Science and Technology, Japan. 相似文献
10.
于2017年6月以三年生无患子Sapindusmukorossi当年生嫩枝作插穗,开展NAA,IAA,GGR6三种激素不同浓度处理对嫩枝扦插的影响试验,于2017年11月对扦插成活率进行统计,并对扦插苗生物量、根系指标和营养元素含量进行测定。结果表明:无患子嫩枝扦插生根方式为中间生根型;NAA100mg·L-1处理的无患子嫩枝扦插当年成活率达46.96%,总根长达到15.65 m,根表面积达到170.25 cm2。三种激素的浓度达500mg·L-1时均能抑制根系生长,导致根表面积和根体积减小。试验表明,采用NAA激素100 mg·L-1浸泡插穗基部1 h对无患子当年生嫩枝扦插影响效果最佳。 相似文献
11.
Rooting ability of cuttings from avocado (Persea americana Mill.) seedlings declined during the first 12 months of development. Cuttings from one-year-old seedlings rooted at a similar rate to cuttings prepared from mature plants. The amount of gibberellin-like substances in the leaves decreased during this time whereas abscisic acid content increased. Application of GA to avocado seedlings induced shoot elongation but failed to maintain the initial, high rooting ability. Treatments with ABA and AM0 1618 had no effect on either rooting or elongation. During the development of roots, the endogenous Avocado Rooting Promoter (ARP) accumulated at a faster rate in juvenile cuttings than in mature cuttings. 相似文献
12.
Bohdan Konôpka Kyotaro Noguchi Tadashi Sakata Masamichi Takahashi Zuzana Konôpková 《Journal of Forest Research》2007,12(2):143-151
Drought stress was simulated in a 28-year-old Japanese cedar plantation (Kanto Plain, Japan) between April and October 2004
by removing throughfall using rain shelters. Changes in fine-root parameters caused by this drought treatment were examined
by sequential soil coring. Drought effects on fine roots were analyzed separately for particular soil depths (0–5, 5–15, and
15–25 cm) and root diameters (<1 and 1–2 mm). Generally, fine-root biomass and root tip numbers decreased by the drought treatment.
Drought stress was most intense for fine roots in the topsoil and weakest for fine roots in the deepest soil layer. Fine roots
less than 1 mm in diameter were affected more severely than 1- to 2-mm roots. The effect of drought treatment was most remarkable
for the number of white root tips, which decreased to 17% of the control at the soil depth of 0–5 cm. These results suggest
that white root tip is the most suitable indicator of drought stress. Simulated drought reduced production of fine roots less
than 1 mm and 1–2 mm in diameter. Fine-root mortality was stimulated for roots less than 1 mm, but not for 1- to 2-mm roots.
These results suggest that fine roots with larger diameters can survive drought stress at a level simulated in this study,
but processes of fine-root production were inhibited regardless of the diameter classes. The duration of drought stress and
phenology of fine roots should also be considered in diagnosing the effects of drought on fine-root parameters. 相似文献
13.
A comparison of pre-planting treatments on hardwood cuttings of four hybrid poplar clones 总被引：1，自引：1，他引：1
Rooting and early growth of four hybrid poplar clones (Populus spp.) planted in a greenhouse were examined after applying 40 pre-rooting treatment combinations to dormant cuttings. Treatments included 2 cutting lengths (5 and 10 cm), 5 soaking times (0, 2, 4, 8, and 12 days), and 4 dips (chitosan, rooting hormone powder, liquid rooting hormone added to the soaking water, and none). Significant differences in both rooting percentages and growth were shown between clones after 7 weeks of growth. Ten cm cuttings had 29% greater rooting success, 28% more above-ground growth, and 12% lower root/shoot ratios than 5 cm cuttings. Cuttings planted without soaking had the lowest rooting success, at less than 45% on average. Commercial rooting hormones decreased the number of rooted cuttings but increased root/shoot ratios. For optimal rooting, we recommend using 10 cm cuttings, soaked for 2 days in water (4 days for the Jackii10 clone) without any additional dipping/hormone substance. 相似文献
14.
Root biomass and root distribution were studied in Entisols derived from the thick deposition of volcanic pumice on Hokkaido
Island, Japan, to examine the effect of soil conditions on tree root development. The soil had a thin (<10 cm) A horizon and
thick coarse pumiceous gravel layers with low levels of available nutrients and water. Two stands were studied: a Picea glehnii–Abies sachalinensis stand (PA stand) and a Larix kaempferi–Betula platyphylla var. japonica stand (LB stand). The allometric relationships between diameter at breast height (DBH) and aboveground and belowground biomass
of these species were obtained to estimate stand biomass. The belowground biomass was small: 30.6 Mg ha−1 for the PA stand and 24.3 Mg ha−1 for the LB stand. The trunk/root ratios of study stands were 4.8 for the PA stand and 4.3 for the LB stand, which were higher
than those from previous studies in boreal and temperate forests. All species developed shallow root systems, and fine roots
were spread densely in the shallow A horizon, suggesting that physical obstruction by the pumiceous layers and their low levels
of available water and nutrients restricted downward root elongation. The high trunk/root ratios of the trees may also have
resulted from the limited available rooting space in the study sites. 相似文献
15.
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
16.
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
17.
Vegetative propagation of Acacia senegal is possible from branch fragments taken from the crown of mature trees (13 years old), without causing ortet destruction.The most responsive planting stock is taken from cuttings 15 cm long (with 12 to 15 nodes) and a diameter of 10 ± 6 mm (wood of 2 to 4 years old). With this material, the ablation of the leaves prior to planting is a factor which furthers development of the cutting's root system.The development of the root system is also highly influenced by the time at which the cutting is taken: results vary from 10% during the dry season to more than 70% during the rainy season (June—October).Cuttings can be taken from branches 50 cm long. It is thus possible to preserve the planting stock for 8 days in a continually humidified jute cloth and then to make the cuttings at the time of establishment in a nursery, without changing their rhizogenic aptitude.The cuttings show characteristics of maturity (slow growth, plagiotropy, fructification). It is nevertheless possible to preserve the collected genotypes in the field, or better, in planting pots in the nursery, so as to further the process of physiologic rejuvenation with the aim of in vitro cloning.researcher at CIRAD/C.T.F.T., detached to ISRA/D.R.P.F. 相似文献
18.
《Scandinavian Journal of Forest Research》2012,27(1-4):481-491
Picea abies mother‐plants from 10 serially propagated clones (14 years old, chronologically) were treated in four different ways: (1) control with intact, non‐manipulated plants; (2) like (1) but with the leader cut off; (3) intact plants but with all branches of the upper two whorls forced to grow in a vertical way; and (4) like (3) but with the leader cut off. Cuttings from four positions (cutting‐types) on the mother‐plants were collected, rooted and evaluated for rooting %, number of main roots, number of lateral roots, plagiotrophy, needle symmetry on leader and growth of leader. Treatments 3 and 4 resulted in cuttings with more plagiotropic growth but with better rooting, more lateral roots and better growth than did cuttings from treatments 1 and 2. The genotype had a significant influence on rooting. Number of main roots was significantly influenced by the genotype and the cutting‐type, but not of the mother‐plant treatment. Symmetry of needles on the leader was fairly weakly influenced by genotype and cutting‐type yet not influenced by mother‐plant treatment. Clone effect was significant for leader growth. 相似文献
19.
Juvenile (2 year old trees) and mature hardwood (15 year old trees) cuttings of Robinia pseudoacacia and Grewia optiva were tested for their capacity to form roots. Cuttings were prepared in spring, monsoon and winter seasons and treated with different concentrations (250, 500 and 750 mg/l) of IBA and NAA. These were planted in a mist chamber maintained at 25±1°C with relative humidity >70%. Juvenile cuttings of both species rooted significantly better than mature hardwood cuttings in all three seasons, and the age effect was more pronounced in auxin treated cuttings. The highest rooting in juvenile (83.3%) and mature (66.6%) cuttings was observed with the NAA (500 mg/l) treatment in R. pseudoacacia during the spring season. In G. optiva, IBA (250 mg/l) in the monsoon season was most effective and yielding a maximum of 80% and 70% rooting in juvenile and mature cuttings, respectively. Auxin treatments also significantly enhanced the number of roots, root length, leaf number and leaf area. Statistical analysis of data revealed that interactions between age, season and treatments were significant at P <0.05 level for R. pseudoacacia and non-significant for G. optiva. 相似文献
20.
The present study aimed at examining the amenability of Stereospermum suaveolens DC. to vegetative propagation through rooting of leafy stem cuttings using low-cost polythene propagators. Rooting efficiencies
of cuttings derived from two selected matured mother trees were studied using four different concentrations of Indole-3-butyric
acid (IBA), viz. 0, 0.1, 0.2 and 0.4%. IBA applied at 40 μg per cutting (0.4% concentration) resulted in significantly higher
rooting responses compared to the control (P < 0.05). Differences in the length of longest root for all the treatments were significant (P = 0.05) with cuttings treated with 0.2% IBA producing the longest root. The highest survival after 3 weeks of transference
of the rooted cuttings into polythene bags was found for rooted cuttings treated with 0.2% IBA. Effects of three fertilizer
treatments viz. T0 (no fertilizer), T1 (10 g of Urea + 20 g of TSP + 10 g of MOP dissolved in 1 l of water) and T2 (10 g of Urea + 20 g of TSP + 10 g of MOP dissolved in 2 l of water) on initial growth of established rooted cuttings (stecklings)
of Stereospermum suaveolens in polythene bags were also measured for a period of 90 days. Stem length, collar diameter and leaf area of the stecklings
increased throughout the observation period. Increments of both stem length and collar diameter were significantly higher
for the stecklings treated with T2 in comparison with the control while increment of leaf area was found the highest for the stecklings treated with T1. The study clearly indicated that Stereospermum suaveolens is amenable to vegetative propagation technique using juvenile single-node leafy cuttings and the initial growth performance
of the established rooted cuttings (stecklings) in polythene bags under different fertilizer treatments was satisfactory. 相似文献