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1.
《Scientia Horticulturae》2005,105(2):197-211
CO2 concentration was monitored during three 15-day subculturing cycles in vessels containing actively proliferating plum cultures of Prunus cerasifera, clone Mr.S. 2/5. The effects of two photosynthetic photon flux density regimes: 50 ± 5 μmol m−2 s−1 and 210 ± 5 μmol m−2 s−1 were compared. Three distinct phases in the CO2 trend were distinguished during each culturing cycle of both light treatments. In the first, occurring at the beginning of the culture cycle, the amount of CO2 emitted by the cultures during dark periods was greater than that assimilated during the light periods. In the second phase, the opposite trend was detected, while in the third, the range of CO2 day–night fluctuations increased or remained stable according to the number of explants per vessel. The treatment with 210 ± 5 μmol m−2 s−1 did not modify the CO2 phase trend but induced more pronounced fluctuations in day–night CO2 concentration. Under this light treatment, cultures reached CO2 compensation point for a period as long as 48% of the total number of light hours, while under 50 ± 5 μmol m−2 s−1, it was only 8%. The different range in CO2 day–night fluctuations monitored throughout a subculturing cycle, appeared to be mainly induced by changes in culture growth dynamics. 相似文献
2.
《Scientia Horticulturae》2005,104(1):11-24
Leaf CO2 assimilation rate, stomatal conductance (gs), internal CO2 concentration (Ci), chlorophyll (a + b) content, specific leaf weight (SLW) and stomatal density were measured during the season, under field conditions, for five major Greek olive cultivars, ‘Koroneiki’, ‘Megaritiki’, ‘Konservolia’, ‘Lianolia Kerkiras’, and ‘Kalamon’, with different morphological and agronomic characteristics and diverse genetic background. Measurements were taken from current-season and 1-year-old leaves, and from fruiting and vegetative shoots, throughout the season, from March to November in years 2001 and 2002. CO2 assimilation rates showed a substantial seasonal variation, similar in all cultivars, with higher values during spring and autumn and lower values during summer and late autumn. Stomatal conductance (gs) followed similar trends to leaf CO2 assimilation rates, increasing from March to July, following by a decrease during August and increasing again in autumn. ‘Koroneiki’ had the highest leaf CO2 assimilation rate and gs values (21 μmol m−2 s−1 and 0.45 mol m−2 s−1, respectively) while ‘Lianolia Kerkiras’ and ‘Kalamon’ showed the lowest leaf CO2 assimilation rate and gs values (13–14 μmol m−2 s−1 and 0.22 mol m−2 s−1, respectively). One-year-old leaves had significantly higher leaf CO2 assimilation rate than current-season leaves from April to June, for all cultivars. From August and then, leaf CO2 assimilation rate in current-season leaves was higher than in 1-year-old leaves. There were no significant differences in leaf CO2 assimilation rate between fruiting and vegetative shoots. Total chlorophyll (a + b) content increased with leaf age in current-season leaves. In 1-year-old leaves chlorophyll content increased in spring, then started to decrease and increased slightly again late in the season. Chlorophyll content was higher in 1-year-old leaves than in current-season leaves throughout the season. Total specific leaf weight (SLW) increased throughout the season for all cultivars. Stomatal density in lower leaf surface was lowest for ‘Koroneiki’ (399 mm−2) and highest for ‘Megaritiki’ (550 mm−2). Our results showed differences in leaf CO2 assimilation rate among the five different olive cultivars, with a diverse genetic background, ranging from 12 to 21 μmol m−2 s−1. From the five cultivars examined, ‘Koroneiki’, a drought resistant cultivar, performed better and was able to maintain higher leaf CO2 assimilation rate, even under high air vapor pressure deficit. All cultivars had a pronounced seasonal variation in leaf CO2 assimilation rate, affected by date of the year, depending on ambient conditions. The high temperatures and high air vapor pressure deficit occurring during summer caused a reduction in leaf CO2 assimilation rate in all cultivars. Leaf CO2 assimilation rate was also affected by leaf age for all cultivars, with old leaves having significantly higher leaf CO2 assimilation rate than young leaves early in the season. 相似文献
3.
《Scientia Horticulturae》2005,104(3):275-292
Forty-one herbaceous species were grown under short-days (8 h photoperiod, ambient irradiance averaged 12–13.2 and 6.4–8.3 mol m−2 day−1 for Experiments I and II, respectively) with or without supplemental high-pressure sodium lighting (+50, 100, or 150 μmol m−2 s−1); or under long-days delivered using natural day lengths and irradiance with night interruption lighting (2200–0200 h at 2 μmol m−2 s−1 from incandescent lamps) or under ambient daylight plus supplemental irradiance during the day and as a day extension to 18 h (0800–0200 h) with supplemental high pressure sodium lighting (+50, 100, or 150 μmol m−2 s−1) to identify the impact of photoperiod and irradiance on flowering of each species. Days to first open flower, leaf number below first flower, and mean dry weight gain per day (MDWG) were measured when the first flower opened. Twenty-seven species were photoperiodic with examples of five photoperiodic response groups represented: obligate short-day (2), facultative short-day (5), obligate long-day (16), facultative long-day (4); 13 were day neutral (no photoperiod response in flowering). One species, Salvia sclarea L., did not flower. A facultative irradiance response was observed with 10 species; 28 species were irradiance indifferent; 2 had delayed flowering as irradiance increased. Photoperiod affected MDWG of 30 species. Increasing irradiance affected MDWG with 14 species. Photoperiod interacted with irradiance to affect MDWG of 11 species. Cobaea scandens had the greatest MDWG (0.40 g day−1) while Amaranthus hybridus had the least MDWG (0.01 g day−1) across photoperiod and irradiance levels. 相似文献
4.
《Scientia Horticulturae》2001,88(1):41-57
Studies were conducted to improve adventitious bud regeneration in roses (Rosa hybrida L.), specifically to extend the protocol to different genotypes and to initiate production of multiple shoots per explant. The best results were obtained by using a two-stage procedure where excised leaflets were incubated on Murashige and Skoog (MS) (1962) induction medium with 6.8 μM TDZ plus 0.49 μM IBA in the dark for 7 days and subsequently transferred to an MS-based regeneration medium with 2.22 μM BA plus 0.049 μM IBA exposed to a PPFD of 15 μmol m−2 s−1 PAR. Bud formation capacity was also significantly affected by the genotype and the environment, such as the use of bottom cooling creating a lower RH in the vessel. The addition of silver nitrate to the induction medium also significantly improved the percentage of regeneration in three genotypes tested. Regenerated shoots failed to elongate when transferred to MS proliferation medium containing 0.5 mg l−1 BA, however maximum bud development and elongation were achieved when kinetin in the range 1–2 mg l−1 was used. Elongated shoots were excised and rooted best on zero growth regulator half-strength MS modified medium. Rooted plantlets were acclimatized under greenhouse conditions for evaluation of somaclonal variation. 相似文献
5.
《Scientia Horticulturae》2001,87(1-2):93-105
Campanula carpatica Jacq. ‘Blue Clips’ plants were grown in a greenhouse under nine combinations of day and night temperatures created by moving plants every 12 h among three day/night temperatures (15, 20, and 25°C). At each temperature, there were three daily light integrals (DLI; 4.2, 10.8, and 15.8 mol m−2 per day, averaged over the experimental period) created with varying supplemental light, and ambient (≈400 μmol mol−1) and enriched (≈600 μmol mol−1) CO2 concentrations. Time to flower was closely related to average daily temperature (ADT), and was not significantly affected by the day or night temperatures delivered to achieve a specific ADT. Time to flower was not largely affected by DLI or CO2 enrichment. As plant ADT increased between 15 and 25°C, flower diameter decreased about 1 mm per degree and was not related to the difference between day and night temperatures (DIF). Flower diameter was smallest and least sensitive to changes in temperature at lower DLI and at ambient CO2 levels. There were 10 less flower buds and 0.3 g less dry mass per plant at first flower for every 1° increase in plant ADT at high and medium DLIs. Flower bud number and dry mass were relatively low and less sensitive to changes in ADT at low DLI, and increased slightly with CO2 enrichment at medium and high but not at low DLI. Plant height was not related to ADT, but increased linearly as DIF increased from −6 to 12°C at all DLIs, but the response was stronger under low DLI than high and medium DLIs. Flower bud number and dry mass were correlated closely with the ratio of DLI to daily thermal time (base temperature of 0°C). Flower bud number and dry mass were highest when C. carpatica plants were grown at 15°C with a DLI of 10–15 mol m−2 per day. 相似文献
6.
《Scientia Horticulturae》2001,87(4):275-290
The optimal growth regulator addenda for adventitious shoot regeneration in epicotyl cuttings of Troyer citrange (Citrus sinensis×Poncirus trifoliata) varied with the conditions of illumination. The response to illumination and to growth regulators differed for the direct and the indirect (through callusing) pathways of regeneration. Shoot formation through the direct organogenic pathway decreased as the concentration of benzyladenine (BA) in the medium was increased in the range 2.2–22 μM, when the explants were incubated in the dark or under an 8 h daylength. For explants incubated under a 16 h daylength, the number of shoots formed increased with BA concentration. Optimal conditions of incubation for shoot formation through the direct pathway were either an 8 h daylength with a photon flux density of 74 μmol m−2 s−1 in the presence of 2.2 μM BA, or a 16 h daylength with a photon flux density of 37 μmol m−2 s−1 in the presence of 22 μM BA. Irrespective of the conditions of incubation, shoot formation through the indirect organogenic pathway was suppressed by the addition of 22 μM BA to the medium. Optimal conditions for shoot formation through this pathway were incubation under an 8 h daylength at a photon flux density of 74 μmol m−2 s−1 in the presence of 2.2 μM BA. At the optimal conditions indicated, the addition of the synthetic auxin naphtaleneacetic acid (0.54 μM) reduced shoot formation. Irrespective of the pathway of regeneration, the number of shoots formed decreased markedly with the distance of the cutting from the cotyledonary node. 相似文献
7.
《Scientia Horticulturae》2001,89(4):249-256
Background pyruvic acid concentration is a critical factor to determine onion pungency but greatly different values have been reported. This study was initiated to measure accurate background pyruvic acid levels in onion cultivars, other Allium species, and non-Allium vegetables using an HPLC method. A microwaving time of 2 min per 100 g was sufficient to deactivate alliinase and further degradation of pyruvic acid was not observed up to 6 min. Five percent trichloro acetic acid was suitable for both fresh and frozen tissues, while 80% ethanol did not stop the alliinase activity completely. The background pyruvic acid concentrations in various onion cultivars were less than 0.34 μmol ml−1, while garlic and onion sprouts were 0.84–0.95 μmol ml−1. Non-Allium vegetable also showed very low levels (0.09–0.34 μmol ml−1) of pyruvic acid in the microwaved tissues. This study confirmed that background pyruvic acid levels in onion were minimal and could be disregarded in a routine analysis. Previous reports of high levels of the background pyruvic acid may need to be reviewed for accuracy. 相似文献
8.
《Scientia Horticulturae》2005,104(1):79-89
The seasonal effect of soil water availability on leaf gas exchange of plantain plants cv. Hartón growing on two different texture soils (loamy and clayey) were evaluated. Soil water deficits corresponded to 48, 24 and 4 days without precipitation. Daily measurements of leaf gas exchange and microclimatic conditions were carried out at 2 h intervals in a humid tropical environment south of Maracaibo Lake, Venezuela. The results show that cv. Hartón is sensitive to conditions of low water deficit on loamy and to a much greater degree on clayey soils. A marked reduction in leaf conductance (gs) was observed under severe as well as moderate deficit (below 50 mmol m−2 s−1) on clayey soils. Under low deficit gs increases to values between 60 and 100 mmol m−2 s−1. The same trend was observed in plants on loamy soils but higher gs for all conditions were obtained compared with plants on clayey soil. Stomatal closure produced a reduction of 85 and 55% of total assimilation (Atot) for severe and moderate deficit in plants on clayey soils, respectively. While plants on loamy soil exhibited a 65 and 35% reduction, respectively. Water use efficiency (WUE) consistently decreased as available soil water decreased on both soil types. Independently of soil water conditions, higher WUE were always obtained for loamy soils. This suggests that cv. Hartón does not have the ability to adjust the CO2 assimilation to transpiration ratio in order to optimize gas exchange. This evidences the importance of maintaining high conditions of available soil water in order to avoid lower assimilation rates that probably influence negatively on yield and fruit quality. 相似文献
9.
《Scientia Horticulturae》2005,104(3):325-337
The influence of 24 h mean air temperature (18.3, 20.6, 23.9 and 25.8 °C) and photosynthetic photon flux (PPF; 0.6, 2.1, 3.7 and 4.7 mol m−2 d−1) on the growth cycles of vegetative growth in Ilex × meserveae (‘Blue Princess’ S.Y. Hu) was investigated. Plants propagated from top cuttings were grown in greenhouse compartments. The number of unfolded leaves was recorded continuously throughout the experiment. A modified sine function was fitted to collected data and the values for the amplitude and frequency of the growth curves were analysed. The sine function was tested as a method to evaluate the influence of climate on periodically flushing species. Both amplitude and frequency were significantly influenced by air temperature and PPF. The highest frequency of flushing was found at 23.9 °C and 3.7 mol m−2 d−1. The function resulted generally in a good fit to collected data with R2 values above 0.9. Growth curves of all individual plants were categorised with respect to their growth pattern as poor synchronisation within the treatments did not allow analysis of the mean values of the growth curves. 相似文献
10.
《Scientia Horticulturae》2005,104(1):25-36
We studied the effects of Fe deficiency on physiological parameters of citrus rootstocks grown in nutrient solution. Three 4-week old rootstocks (‘Troyer’ citrange – Citrus sinensis (L.) Osb. × Poncirus trifoliata (L.) Raf., Citrus taiwanica Tan. and Shim., and ‘Swingle’ citrumelo – Poncirus trifoliata (L.) Raf. × Citrus paradisi Macf.) were grown in nutrient solutions with 0, 5, 10, 15 and 20 μmol Fe dm−3. Calcium carbonate (1 g dm−3) was added to all solutions to mimic the natural conditions in calcareous soils. For each rootstock, shoot length, number of leaves, and root and shoot dry weights were measured at the end of experiment. Chlorophyll concentration was estimated using a portable SPAD-502 meter calibrated for each rootstock. The amount of nutrients (P, K, Mg, Ca, Fe, Zn, Mn, and Cu) was determined in shoots. Chlorophyll fluorescence parameters (F0: basal fluorescence; Fm: maximum fluorescence; Fv = Fm − F0: variable fluorescence) were measured with a portable fluorimeter. ‘Troyer’ citrange rootstock was the most tolerant to Fe deficiency. These plants grew more and accumulated more chlorophyll and nutrients than the others in the presence of low levels of Fe (10 μmol Fe dm−3). ‘Swingle’ citrumelo plants needed 20 μmol Fe dm−3 in the nutrient solution to secure adequate growth. ‘Taiwanica’ orange rootstock had an intermediate behaviour, but could be distinguished from ‘Troyer’ citrange based on fluorescence parameters, since there was a variation in the basal fluorescence in the former, whereas in ‘Troyer’ citrange the basal fluorescence was not affected by the supply of Fe. 相似文献
11.
《Scientia Horticulturae》2005,106(1):70-75
The objective of this study was the comparison of the effect of two Mn sources (MnSO4·H2O, MnEDTA) which were applied at various concentrations (0, 200, 400, 800, and 1200 mg Mn l−1) to the leaves of ‘Washington navel’ orange trees in order to correct Mn deficiency.One hundred and seventy days after the foliar application of Mn solutions, the mean Mn concentrations in the leaves treated with MnSO4·H2O (200, 400, 800 or 1200 mg Mn l−1) or MnEDTA (400, 800 or 1200 mg Mn l−1) were significantly higher than those of the control leaves. Manganese sulfate (MnSO4·H2O) was more effective than MnEDTA regarding the improvement of the leaf Mn concentrations of the trees, when applied at equal Mn concentrations. Finally, the leaf Mn concentrations were in the sufficiency range (>25 mg kg−1 d.w.), only after the application of 800 or 1200 mg Mn l−1 as MnSO4·H2O. 相似文献
12.
《Scientia Horticulturae》2002,92(1):1-7
Barbados cherry fruit shows a biphasic pattern of growth whether monitored on a diameter or weight basis. Each growth phase was of about 2 weeks duration with weight gains of equal magnitude but with most of the size increase occurring in the first phase. Pyrene growth paralleled that of the whole fruit. Cell division was limited to the first week of fruit development and horticultural maturity was reached when fruit showed colour break (18 days post-anthesis). Barbados cherry is climacteric with a very high peak respiratory rate (900 ml CO2 kg−1 h−1) but a low rate of peak ethylene production (3 μl C2H4 kg−1 h−1), the former consistent with its high perishability. 相似文献
13.
《Scientia Horticulturae》2005,106(2):190-202
The response of petunia (Petunia x hybrida Vilm.-Andr. ‘Countdown Burgundy’) and impatiens (Impatiens wallerana Hook ‘Accent Orange Tempo’) to Prohexadione-calcium was evaluated under a clear and a far-red light absorbing greenhouse (AFR) film to investigate the dosage effect of Prohexadione-Ca and to determine if it can overcome the flowering delay under FR deficient greenhouse environments. Prohexadione-Ca reduced stem elongation of petunia and impatiens under AFR and clear films when applied 3 weeks after germination. Late applications were less effective. In both crops, main stem length decreased in a quadratic pattern as the concentration of Prohexadione-Ca increased. Under both films, 50–100 mg l−1 Prohexadione-Ca resulted in ≈30% shorter petunia plants. Greater concentrations (500 and 1000 mg l−1) resulted in excessively short plants (over 70%). Prohexadione-Ca at 100 mg l−1 delayed anthesis of petunia by 8 and 3 days under the clear film and the AFR film, respectively during less inductive photoperiods but had no effect during inductive photoperiods. In impatiens, Prohexadione-Ca at 100 mg l−1 delayed anthesis over 10 days under clear or AFR film. Greater concentrations (200 and 300 mg l−1) inhibited flowering of impatiens. Prohexadione-Ca treatments significantly affected flower color development. Untreated petunia plants had dark burgundy flowers. Prohexadione-Ca treatment increased L*, a*, and C* values and decreased hue angle indicating that the flowers were faded. Flowers of untreated impatiens plants were bright orange color. Prohexadione-Ca at 100 mg l−1 increased L* value and decreased a*, b*, and C* values indicating that significant petal fading had occurred. Flowers of treated plants were nearly white under both films. Although effective in height control, loss of color would be a major limitation to the use of Prohexadione-Ca on flowering crops. 相似文献
14.
Urban parks form the largest proportion of public green spaces contributing to both physical and mental well-being of people living in urban areas. CO2 sequestration capability of the vegetation developing in parks of four historical residences (Villa Pamphjli, Villa Ada Savoia, Villa Borghese and Villa Torlonia) in Rome and its economic value were analyzed. Villa Pamphjli and Villa Ada Savoia having a larger vegetation extension (165.04 ha and 134.33 ha, respectively), also had a larger total yearly CO2 sequestration per hectare (CS) (780 MgCO2 ha−1 year−1 and 998 MgCO2 ha−1 year−1, respectively) than Villa Borghese (664 MgCO2 ha−1 year−1) and Villa Torlonia (755 MgCO2 ha−1 year−1), which had a lower vegetation extension (56.72 ha and 9.70 ha, respectively). CS was significantly correlated with leaf area index (LAI). The calculated CS for the four parks (3197 MgCO2 ha−1 year−1), corresponding to 3.6% of the total greenhouse gas emissions of Rome for 2010, resulted in an annual economic value of $ 23537 /ha. 相似文献
15.
《Scientia Horticulturae》2001,88(1):11-29
We investigated the hypothesis that manipulating water out-flow of a plant through the shoot environment (potential transpiration, ET0) in a glasshouse could modulate the effect of salinity/osmotic potential in the root environment upon yield of tomatoes. Contrasting root-zone salinity treatments were combined with two climate treatments — a reference (high transpiration, HET0) and a “depressed” transpiration (low transpiration, LET0). The salinity treatments, characterised by their electrical conductivity (EC) were 6.5, 8 and 9.5 dS m−1, were always coupled with a reference treatment of EC=2 dS m−1. In another experiment, concentrated nutrients (Nutrients) and nutrients with sodium chloride (NaCl) at the same EC of 9 dS m−1 were compared.Marketable fresh-yield production efficiency decreased by 5.1% for each dS m−1 in excess of 2 dS m−1. The number of harvested fruits was not affected; yield loss resulted from reduced fruit weight (3.8% per dS m−1) and an increased fraction of unmarketable harvest. At the LET0 treatments, yield loss was only 3.4% per dS m−1 in accordance with the reduction in fruit weight. Low transpiration did increase fruit fresh yield by 8% in both NaCl and Nutrients treatments at an EC=9 dS m−1. Neither EC nor ET0 affected individual fruit dry weight. Accordingly, fruit dry matter content was significantly higher at high EC than in the reference (4% per each EC unit in excess of 2 dS m−1) and responded to ET0 to a minor extent. Control of the shoot environment in a greenhouse to manipulate the fresh weight of the product may mitigate the effects of poor quality irrigation water without affecting product quality. 相似文献
16.
Increasing use of recycled water that is often high in salinity warrants further examination of irrigation practices for turfgrass health and salinity management. A study was conducted during 2011–2012 in Riverside, CA to evaluate the response of perennial ryegrass (Lolium perenne L.) ‘SR 4550’ turf to varying quality and quantity of irrigation water. A modified line-source sprinkler irrigation system provided a salinity gradient (ECw ∼0.6–4.2 dS m−1) in between lines. Irrigation was scheduled in four separate irrigation zones perpendicular to the irrigation lines according to 80, 100, 120, and 140% ETo. Changes in turf quality (R2 = 0.30***), were primarily driven by the number of days that the area had been irrigated with saline water. When data were separated by irrigation amount, both time and water quality accounted for 54% and 46% of the variability (P < 0.001) in quality and cover, respectively at 80% ETo. A model was created to quantify decline in turf quality in relationship to %ETo replacement and salinity accumulation in the rootzone (R2 = 0.57). Our results suggest that perennial ryegrass requires irrigation scheduling at 140% ETo, irrigation water quality below ECw ∼1.7 dS m−1, and ECe below 3.8 dS m−1 to maintain acceptable quality for 442 d in Riverside, CA. 相似文献
17.
《Scientia Horticulturae》2001,89(2):115-128
The possible application of some less commonly used in vitro growth regulating compounds is outlined. A number of treatments were applied to determine the best way of inducing in vitro shoot proliferation and rooting on a modified Driver–Kuniyuki [HortScience 19 (1984) 507] basal medium of lemon (Citrus limon (L.) Burm, f. cv. Interdonato) seedlings. 6-Benzyladenine (BA) alone (1, 2 and 4 mg l−1) and in combination with either orange juice (10%, v/v), silver nitrate (3 mg l−1), gibberellic acid (GA3) (0.1 mg l−1 at the establishment stage and 0.5 mg l−1 at all combinations during the proliferation stage) or abscisic acid (ABA) (0.2 mg l−1 only at the establishment stage) were used to stimulate shoot formation during the establishment and the proliferation stage. The combination of BA with ABA gave a high rate of shoot formation, while GA3 and silver nitrate enhanced shoot elongation. When these shoots were transferred to the rooting stage, the effect of application of two different auxins (indole-3-butyric acid (IBA) and α-napthaleneacetic acid) was examined, as well as different methods of application (auxin added to the basal medium and auxin application by dipping the base of the explant in auxin solution). Dipping the base of the explants in a 50% ethanol solution of IBA at 1000 mg l−1 for 5 s resulted in 80% rooting with subsequent 90% survival of these explants, during acclimatization under mist. 相似文献
18.
《Scientia Horticulturae》2005,107(1):90-96
Somatic embryogenic cell suspension cultures of four ginger cultivars were established. Somatic embryogenic calli were induced from ginger shoot tips on MS agar medium supplemented with 1.0 mg l−1 2,4-D and 0.2 mg l−1 Kn, which contained only half concentration of NH4NO3. Rapid-growing and well-dispersed suspension cultures were established by subculturing this kind of callus in the same liquid MSN medium. The suspension cultures (about 1–2 mm in diameter) were placed on the MSN agar medium for callus proliferation. Thereafter embryogenic callus (1.5 cm2) was transferred to solid media (MS + 0.2 mg l−1 2,4-D + 5.0 mg l−1 BA + 3% sucrose + 0.7% agar). Somatic embryos produced shoots and roots, and shoots developed into complete plantlets on solid MS medium supplemented with 3.0 mg l−1 BA and 0.1 mg l−1 NAA. The relationship between the DW of suspension cultures and pH changes in medium is also discussed. The suspension cultures still kept their vitalities after subculture for 8 months. 相似文献
19.
《Scientia Horticulturae》2005,103(2):227-232
Shoot tips from field grown, mature plants of Carissa carandas cv. Pant Sudarshan were cultured on Murashige and Skoog’s (MS) basal medium supplemented with benzyladenine (BA) and indolebutyric acid (IBA) during different seasons. The maximum sprouting rate was obtained with 1.5 cm long explant collected in spring season (February–March) followed by those collected in summer season (April–June). Shoot proliferation was highest on MS basal media supplemented with 3.0 mg l−1 BA. Rooting of microshoots was noted to be the best in 1/2 MS plus 0.8 mg l−1 IBA and 0.2 mg l−1 naphthalene acetic acid (NAA). The rooted plantlets were successfully acclimatized in vermiculite:sand:soil (1:1:1) potting mixture. 相似文献
20.
《Scientia Horticulturae》2002,95(3):251-260
A number of experiments were conducted to identify suitable procedure for in vitro shoot multiplication of Persian walnut (Juglans regia L.). Three different nutrient media (DKW, MS and WPM) and three different gelling agents (Phytagel, Difco Bacto agar and a mixture of Phytagel and Difco Bacto agar) were studied in the first experiment. Driver and Kuniyuki walnut (DKW) medium solidified with 2.2 g l−1 Phytagel was found optimum. Performance of explants was better on DKW medium than on MS and WPM. The DKW and MS media were not significantly different from each other, but both of them were significantly better than WPM, which was a very poor medium for this species. Phytagel alone was significantly better than Difco Bacto agar or Phytagel combined with Difco Bacto agar. In another experiment different concentrations of BA were studied. Medium containing 1.0 mg l−1 BA and 0.01 mg l−1 IBA was the best, although medium containing 0.6 and 0.8 mg l−1 BA were also successful, and utilisation of 0.4 mg l−1 BA and 0.01 mg l−1 IBA was optimum for shoot elongation. Application of different kinds of auxins (IAA, IBA and NAA at 0.01 or 0.1 mg l−1) with 1.0 mg l−1 BA were also studied. Media containing IBA were significantly better than media containing IAA for shoot fresh weight, but neither of them was significantly different from media containing NAA. Application of 0.01 mg l−1 or 0.1 mg l−1 auxin, with 1.0 mg l−1 BA, was not significantly different for shoot multiplication of Persian walnut. The morphology of shoots on media containing 0.01 mg l−1 IBA was the best. 相似文献