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1.
《Scientia Horticulturae》2005,107(1):43-50
This study was planned to evaluate the effect of preharvest calcium sprays on physicochemical aspects of cell wall components, activity patterns of pectin-modifying enzymes and susceptibility to brown rot (Monilinia fructicola) of peach fruits (Prunus persica L. cv. ‘Andross’). Six or 10 preharvest calcium sprays were applied with two different formulas (calcium chloride and an ethylenediamine tetraacetic acid (EDTA) chelated calcium form) in equimolar calcium concentration (0.12% Ca, w/v). After harvest, peach fruits were cold stored (0 °C, 95% R.H.) up to 4 weeks. Calcium content increased significantly in the calcium-sprayed peaches both in the peel (25–42%) and in the flesh (11–17%), 1 d after harvest. Calcium chloride sprays were more effective than those of chelated calcium, whereas the increase of calcium content in the fruits seems to be unaffected by the 6 or 10 calcium sprays. The increase of cell wall calcium corresponded to increase of calcium in the insoluble pectin fraction, whereas no differences were detected in the calcium of water-soluble pectin fraction. Ethylene production, respiration rate, uronic acid content and activity of pectin-modifying enzymes did not indicate substantial differentiations by preharvest calcium sprays as ripening progressed after harvest or cold storage. Calcium sprays resulted in significant decrease of brown rot development, although no effect on disease incidence was recorded.  相似文献   

2.
《Scientia Horticulturae》2002,95(4):297-308
Studies were conducted to investigate how harvest maturity influence fruit ripening processes to alleviate chilling injury (CI) in mangoes (cv. Tommy Atkins). Fruit at three stages of maturity, immature (M1), half-mature (M2) and mature (M3) were stored for 18 days at 5 °C and then at 1 or 3 days at 20 °C. M1 fruit succumbed to CI after 18 days at 5 °C, with symptoms increasing in severity upon warming. Low C2H4 production, poor colour development, minor changes to fruit composition, insipid flavour and poor aroma revealed that fruit ripening was insufficient to reduce CI compared to M2 and M3 fruits. M2 and M3 fruits had higher C2H4 production rates than M1 fruit and ripened normally with acceptable flavour and aroma after 18 days at 5 °C and 3 days at 20 °C. While M3 fruit had no CI symptoms, they were overripe and fruit decay incidence was 26.6%, compared to M2 fruit which had no decay, a trace of CI symptoms and possessed the best overall quality.  相似文献   

3.
《Scientia Horticulturae》2001,88(2):107-120
Methyl jasmonate (MJ) and CMN-pyrazole alone and in combination were applied to ‘Hamlin’ and ‘Valencia’ orange trees (Citrus sinensis (L.) Osbeck) in seven separate experiments in the 1998/1999 and 1999/2000 growing seasons to induce abscission of mature fruit for mechanical harvesting. MJ alone significantly reduced fruit detachment force (FDF) of ‘Hamlin’ oranges at concentrations of 10 mM and higher. However, MJ at 20 and 100 mM caused significant defoliation. For ‘Hamlin’ oranges, the most effective treatments were those combining 10 mM MJ and 50 mg l−1 CMN-pyrazole, and 20 mM MJ and 25 mg l−1 CMN-pyrazole. ‘Valencia’ oranges did not respond to 10 mM MJ treatments alone or in combination with CMN-pyrazole, and required MJ at 20 mM in combination with CMN-pyrazole to loosen this late-maturing variety to below 50 N, but excessive defoliation occurred.  相似文献   

4.
《Scientia Horticulturae》2005,103(3):289-303
In a 2-year field study, strawberry cvs. ‘Elsanta’ and ‘Korona’ were exposed to three different levels of NaCl salinity supplied as aqueous solutions characterised by electrical conductivities of 0.3 dS/m, 2.6 dS/m, and 5.1 dS/m. Salinity in the rhizosphere reduced plant growth by up to 44% in ‘Korona’ and 90% in ‘Elsanta’. A rather distinct cultivar difference represented the reduction in leaf area per plant of 85% in the second year of experiment in ‘Elsanta’ compared to 29% in ‘Korona’. Strawberry can be regarded as a Na+ excluder, because Na+ content of both strawberry cultivars remained below 3 mg g−1 dry mass at all salinity levels. Cl− content increased considerably, up to 70 mg g−1 dry mass in ‘Korona’ and 80 mg g−1 dry mass in ‘Elsanta’ plants. ‘Korona’ retained most of its Cl− in roots and crowns, whereas in ‘Elsanta’ the maximum was detected in petioles. ‘Korona’ was able to accumulate up to 33% higher Cl− content in the roots than ‘Elsanta’. Macronutrient deficiency due to NaCl salinity was not observed and in comparison to ‘Elsanta’, higher Cl− content in roots of ‘Korona’ did not coincide with an impairment of macronutrient uptake. Salinity stress reduced fruit yield by up to 27% in ‘Korona’ and 64% in ‘Elsanta’. Fruit quality, characterised as taste, aroma, and texture by a consumer-type panel, decreased by more than 24% in ‘Elsanta’, but in ‘Korona’ differences were insignificant. Total soluble solids (Brix) and the ratio Brix/TA (TA, titratable acid) decreased significantly by about 20% in ‘Korona’ and 35% in ‘Elsanta’. To summarise, the ability of ‘Korona’ to retain Cl− in the root system more effectively than ‘Elsanta’ resulted not only in a 41% lower leaf Cl− content at the highest salinity level and a better growth under NaCl stress, but also in a relatively higher fruit yield and fruit quality.  相似文献   

5.
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   

6.
《Scientia Horticulturae》2005,106(3):341-352
Peppers (Capsicum spp.) were grown for phytochemical analyses at three different locations including a greenhouse at College Station and field plots at Uvalde and Weslaco, Texas. Cultivar effects were significant at each location for all compounds. The best sources of β-carotene were mature greenhouse-grown fruit of Fidel (23.7 μg/g) and C 127 (22.3 μg/g). Mature greenhouse fruit of Tropic Bell (10.1 μg/g) and PI 357509 (9.2 μg/g) had high lutein, but Uvalde field-grown mature fruit of these lines were low in this compound, (1.4 and 0.5 μg/g, respectively). MJ 201 fruit had the highest zeaxanthin levels (10 μg/g) at both College Station and Uvalde. The best sources of quercetin over all locations were the yellow wax types, Banana Supreme (186 μg/g), PI 357509 (86 μg/g) and Rio Grande Gold (26 μg/g). Fidel (37 μg/g) and Banana Supreme (21.5 μg/g) were the best sources of luteolin. Immature fruit generally contained lower levels of lutein and xeaxanthin than mature, colored fruit. These differences were not always statistically significant. Greenhouse-grown peppers at College Station contained more carotenoids than the field-grown peppers in Uvalde and Weslaco, but there were no significant differences among locations for flavonoid concentrations. Several good candidate parents were identified for the breeding program to develop novel pepper varieties with increased health benefits. Families of these varieties are currently being examined to assess the impact of specific environmental factors and identify genes involved in regulating synthesis of these beneficial phytochemicals.  相似文献   

7.
《Scientia Horticulturae》2001,89(4):317-324
Some factors (light, prechilling, gibberellic acid, ethylene) affecting germination of seeds of Echinacea angustifolia DC. were investigated. Without any pretreatment, the seeds germinated better in darkness than in light, however, percentages germination were low in both cases. GA3 did not increase germination in light. Prechilling for 7–15 days in light or in darkness hardly affected percentage germination but significantly increased the rate of germination. Ethephon during prechilling resulted in a large increase of percentage and rate of germination in light, but had hardly any effect on germination in darkness. The results showed that a prechilling treatment for about 11 days at 5°C in a 1 mM ethephon solution in continuous light, followed by a 2-week germination period in light (24 h per day) at 20/30°C, can induce >90% seed germination in E. angustifolia. The prechilling treatment in ethephon also increased the rate of germination.  相似文献   

8.
Effect of ethephon (2-chloroethylphosphonic acid) application on rabbiteye blueberry fruit quality during the growth period was investigated. Ethephon treatment stimulated the decrement of titratable acidity, anthocyanin accumulation and fruit softening 4 days after treatment and the promoting effects continued through the investigation period. The ripening promotion effect of ethephon on total soluble solids content was observed only 8 days after treatment. Ethephon treatment did not affect the fruit enlargement during the investigation period. From these results, it is concluded that ethephon application for rabbiteye blueberry promote the fruit ripening, but the stimulatory effects of ethephon on fruit ripening were different in degree on each ripening characters.  相似文献   

9.
《Scientia Horticulturae》2005,106(2):203-212
Cultivation of roses in various soil-less media was studied with the aim to identify the optimum soil condition for rose production. Madelon roses grafted on rootstock of Rosa indica var. major were transplanted to polyethylene bags containing zeolite and perlite (at ratios of 25z:75p, 50z:50p, 75z:25p and 100z:0p, v/v) in a climate-controlled greenhouse. Net photosynthesis (Anet), stomatal conductance (gs) and water use efficiency (WUE) of roses were followed for 5 months. Flower production and quality were recorded in three flowering flushes during a 5-month period. Analysis of variance of repeated measurements showed that even though the overall Anet did not differ among treatments (average 18.7 μmol m−2 s−1), trends in Anet seasonality for roses in 25z:75p substrate differed significantly from those in 50z:50p, 75z:25p or 100z:0p. Stomatal conductance did not show any significant seasonality or trends in response to substrate mixtures, averaging 0.89 mol m−2 s−1. Water use efficiency was significantly lower for roses in 25z:75p than in 100z:0p mixtures (1.8 ± 0.15 and 2.0 ± 0.13 μmol m−2 s−1 CO2/mmol m−2 s−1 H2O, respectively). Cumulative production of rose plants did not differ among substrate mixtures. Productivity significantly differed among flower stem classes. Stem class I (>70 cm) and class V (≤30 cm) exhibited the least production, contributing to only 7.6 and 3.7% of the total production, respectively. The highest productivity was observed in classes III (51–60 cm) and IV (31–50 cm), contributing to the bulk of productivity (68.4%). Class II contributed a 20.3% of the production. Results showed that zeolite and perlite acted as inert materials. Zeolite did not exert any positive effect on productivity, in contrast to what has been reported in literature recently. Use of perlite resulted in a little improvement in photosynthesis, however this improvement was not reflected by a significant increase in production.  相似文献   

10.
Two separate trials during 2007 and 2008 were conducted using containerized white flowering horse chestnut trees (Aesculus hippocastanum L.) to assess the efficacy of a range of insecticides applied at three different times during a growing season against the insect pest, horse chestnut leaf miner (Cameraria ohridella Deschka and Dimic; HCLM). Insecticides were timed to coincide with the emergence of the adult moth, the target organism. A conventional synthetic insecticide (deltamethrin) used within the UK for HCLM control was included for comparison. A marked impact of insecticide type and frequency of application on HCLM severity was recorded. The effectiveness of each insecticide on mean number of HCLM mines per leaf and percent HCLM larvae/pupae mortality increased when applied at increasing frequencies, i.e. three sprays provided a higher degree of control than two sprays while two sprays provided a higher degree of control than one spray. Limited efficacy as HCLM protectant compounds was demonstrated when the insecticides pyrethrum and soap were applied, irrespective of number of applications. The synthetic insecticide deltamethrin and insect growth regulator diflubenzuron provided the greatest degree of HCLM control. In some instances two foliar sprays provided 100% HCLM control. Efficacy of remaining insecticides based on reduction of HCLM mines per leaf after three sprays averaged across both the 2007 and 2008 trials was in the order silicon dioxide > alginate/polysaccharide combination > organic plant extract > spray oil. Results show commercially registered insecticides exist that provide growing season control of HCLM provided two sprays are applied.  相似文献   

11.
Two separate trials during 2010 and 2011 were conducted using field grown white flowering horse chestnut trees (Aesculus hippocastanum L.) to asssess the insecticidal efficacy of three systemic inducing agents (SIR), namely (Messanger (active substance (a.s.) Harpin protein), Phoenix (a.s. Potassium phosphite) and Rigel (a.s. Salicylic acid derivative) applied to coincide with the appearance of each adult generation of the insect pest, horse chestnut leaf miner (Cameraria ohridella Deschka and Dimic; HCLM). A conventional synthetic insecticide (deltamethrin) used within the UK for HCLM control was included for comparison. A marked impact of SIR inducing agent and frequency of application on HCLM severity was recorded. The effectiveness of each SIR inducing agent on mean number of HCLM mines per leaf and percent HCLM larvae/pupae mortality increased when applied at increasing frequencies i.e. three sprays provided greater control than two sprays while two sprays provided greater control than one spray. The synthetic insecticide deltamethrin provided the greatest degree of HCLM control with two foliar sprays providing 100% HCLM control. Efficacy of SIR inducing agents based on reduction of HCLM mines per leaf after three sprays averaged across both the 2010 and 2011 growing seasons was in the order potassium phosphite > salicylic acid derivative > harpin protein > water control where leaf mining activity was reduced by 35–64%. Enhancement of leaf phenolic content was indicated as a means by which SIR agents reduced leaf mining activity. Results show commercially available SIR inducing agents exist that provide potentially acceptable degrees of HCLM control provided at least two sprays are applied during a growing season.  相似文献   

12.
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   

13.
《Scientia Horticulturae》2005,107(1):36-42
In clayey and calcareous soils without a stable irrigation and fertilization system, the type of rootstock can particularly affect both the vegetative and productive properties of ‘Suncrest’ peach (Prunus persica L. Batsch) plants, and the qualitative and nutritional attributes of their fruit. The GF677 rootstock (P. persica × Prunus amygdalus) promoted the highest vegetative development, followed by Julior (Prunus insistitia). The ‘Suncrest’ on Ishtara [(Prunus cerasifera × P. persica) × (P. cerasifera × Prunus salicina)] and Barrier1 (P. persica × Prunus davidiana) had lower, but similar, plant vigour, but the latter rootstock differed in its higher production of pruned wood. The lowest adaptability to these cultivation conditions was observed for ‘Suncrest’ grafted onto Citation (P. persica × P. salicina), which showed the lowest plant development and production. For the plant yield, the ‘Suncrest’ grafted onto GF677, Julior, Ishtara, and Barrier1 were all similar. The fruit yield and both the canopy volume and pruned wood of ‘Suncrest’ grafted onto Ishtara showed a particular relationship, giving the best indices of yield efficiency and plant physiological equilibrium. Moreover, the same rootstock promoted the largest fruit size, while the smallest fruit were found on GF677 rootstock. The fruit from the Citation ‘Suncrest’ ripened 3 days early, while those from Barrier1 had a late fruit ripening. Firmness, soluble solids and the soluble solids to total acidity ratio were only affected slightly by the different rootstocks, while the total acidity of the fruit varied significantly according to rootstock; the fruit from ‘Suncrest’ grafted onto Barrier1, Julior, and Citation had the highest total acidities. The rootstock effects on the nutritional attributes of the fruit were relevant. The ‘Suncrest’ on Julior and GF677, followed by Ishtara, produced fruit with the greatest antioxidant activities and total phenolic contents. The ‘Suncrest’ on Citation and, especially, Barrier1 had reduced nutritional values of the fruit. The variations in antioxidant activities and total phenolic contents showed a positive correlation.  相似文献   

14.
‘Hayward’ kiwifruit were stored at 0, 5, 10, 15 and 20°C for 5, 12 and 17 days before rewarming to 20°C for 10 more days. Ethylene and CO2 production, ACC, ACC synthase (ACS) and ACC oxidase (ACO) activities, flesh and core firmness, soluble solids content (SSC) and flesh colour were measured. Kiwifruit stored at 0, 5, 10 and 15°C did not ripen, produce ethylene or show increases in ACS or ACO activity. Fruit stored for 5 days at the above temperatures, then rewarmed to 20°C, did not show any change during the following 10 days. Rewarmed fruit, pre-stored at 0–10°C for 12 days, started autocatalytic ethylene production within 24 h, followed by fruit ripening. Fruit stored at 15°C for 12 days needed 72 h to start ethylene autocatalyse and did not fully ripen during 10 days at 20°C. After 17 days storage at 0–15°C kiwifruit started autocatalytic ethylene production with no delay upon exposure to 20°C. Autocatalytic ethylene production correlated with increased ACC content, and increased activities of ACS and ACO. Fruit held continuously at 20°C started autocatalytic ethylene production after 19 days, with concomitant increases in ACC content, ACS and ACO activities and ripening. Respiration increased after rewarming, concomitantly with the increase in ethylene production.We concluded that exposing kiwifruit to chilling temperatures (0–10°C) for 12 days advanced ethylene biosynthesis and ripening when compared with fruit held continuously at 20°C. The advanced ethylene biosynthesis was due to increase ACS and ACO activities immediately upon rewarming of the fruit.  相似文献   

15.
《Scientia Horticulturae》2005,104(3):265-273
In Japan, artificial pollination is practiced to improve fruit set as well as fruit size and to obtain perfect round shapes in ‘Housui’ (S3S5) Japanese pear and most commercial cultivars that present gametophytic self-incompatibility. The period of artificial pollination application is limited by environmental conditions and the availability of a labor force. The present study aimed to determine if pre-pollination applications of putrescine (1.0 and 0.01 mM) positively affect fruit set in ‘Housui’ after hand-pollination. During 2002 and 2003, fruit set in late pollinated flowers increased with pre-pollination putrescine applications and concentrations of 1.0 mM had a better effect than 0.01 mM. In vitro pollination tests revealed that higher pollen germination was present in the stigmas of flowers sprayed with 1.0 mM of putrescine compared to the controls. Putrescine application did not affect post-pollination ethylene production in the styles. Moreover, in the styles of non-treated flowers, an increment of putrescine content and ethylene production after pollination was found, suggesting post-pollination responses and confirming the lack of antagonism between polyamines and ethylene at least during this process.  相似文献   

16.
《Scientia Horticulturae》2005,107(1):51-57
Interploid crosses of diploid Kinnow mandarin, Succari sweet orange and Sweet lime with tetraploid Kinnow were made reciprocally for the production of triploid plants. Low fruit set and occurrence of underdeveloped or empty seeds was common in all interploid crosses. The hybrid fruits harvested after 12–14 weeks or 7 months after pollination produced many underdeveloped and few developed seeds; however, tetraploid Kinnow as seed parent yielded more developed seeds per fruit. The under developed seeds were devoid of endosperm. Nucellar embryony was higher in the diploid than in the tetraploid strain of Kinnow. Immature embryos of seeds harvested 12–14 weeks after pollination were cultured in vitro on MS media supplemented with adenine sulphate (20 mg l−1) and malt extract (500 mg l−1). Maximum germination (75%) of hybrid embryos from underdeveloped seeds was obtained in 4× × 2× cross of Kinnow strains. The germinated plantlets were transferred into pots and noted 59–89.3% survival rate in various crosses.  相似文献   

17.
《Scientia Horticulturae》2001,89(2):143-154
The effectiveness of two commercial formulations of gibberellin (GA) and benzyladenine (BA) for reducing foliar chlorosis on Easter lily (Lilium longiflorum Thunb.) was compared. On a per liter basis, plants were sprayed with 0, 100, 200, or 400 mg (BA equivalent) of Accel (GA4+7:BA of 1:10) or Promalin (GA4+7:BA of 1:1) when the crop leaf area index (LAI)=3. One group of plants was sprayed with 100 mg of Accel or Promalin (BA equivalent) per liter twice: once at LAI=3 and again 3 weeks later. Plants were harvested when the largest flower bud on each plant measured 13 cm in length, stored for 0 or 3 weeks at 2.5°C in the dark, and then moved into a post-harvest evaluation room at 21°C, where foliar chlorosis was monitored for 3 weeks. Senescence of some lower leaves on plants in every treatment was evident at harvest, and incidence of senescence increased during the 21 days of post-harvest evaluation. Cold storage increased the number of leaves senescing during the subsequent evaluation period. Application of Promalin or Accel significantly reduced leaf senescence compared to that of untreated plants. At harvest, 21% of the leaves on untreated plants were senescent, while plants treated with Promalin or Accel averaged 3 or 9% senescent leaves, respectively. Following 7 days of post-harvest evaluation, Promalin was more effective in preventing chlorosis than Accel at the 400 mg l−1 (BA equivalent) level. Following 14 or 21 days of post-harvest evaluation, Promalin was more effective than Accel for the 100 mg l−1 2× and 400 mg l−1 (BA equivalent) treatments.Plants in all Promalin and Accel treatments were taller than untreated plants 1 week after sprays were applied. At harvest, plants sprayed with Promalin were between 6 and 14 cm taller than untreated plants, but those treated with Accel were the same height as untreated plants.Neither Promalin nor Accel influenced the occurrence of malformed or aborted flowers in this study. However, cold storage significantly increased the number of plants with aborted buds and malformed flowers. Unstored plants averaged 0.16 aborted buds and 0.02 malformed flowers each, while those stored 3 weeks averaged 0.51 aborted buds and 0.18 malformed flowers each.  相似文献   

18.
Some practitioners within the green industry have lauded the application of sugar-containing products to the soil around trees as a method to improve plant health. A research study was initiated to evaluate the effects of exogenous applications of glucose and starch on the growth and vitality of healthy live oaks (Quercus virginiana P. Miller). Glucose, starch, or a 50:50 mixture of both carbohydrates were applied as soil drenches around 60 young live oaks growing at a field nursery. Carbohydrates were dissolved in water and applied at concentrations of 0, 40, 80, and 120 g L?1 within 0.5 m from the trunk. Solutions were applied using 10 L per application every four months during an 18-month period. Trunk diameter, root and canopy growth, and carbohydrate content of twigs and roots were measured every four months, and net photosynthetic rate, chlorophyll fluorescence, and soil respiration were measured every six months. Tissue samples from twigs and roots were collected after 16 months to measure carbon isotope composition (δ13C) as an indicator of carbohydrate uptake. Chlorophyll fluorescence varied throughout the experiment but did not demonstrate a clear trend. Higher carbohydrate applications did influence the concentration of glucose in twigs although the results did not clearly indicate that this effect was caused by an uptake of glucose from roots. δ13C signatures did not provide any evidence about potential carbohydrate uptake. Even though there was a significant increase in soil respiration after being treated with starch, no significant increase in growth or vitality was detected on healthy live oaks.  相似文献   

19.
《Scientia Horticulturae》2005,105(3):331-342
The germination of loquat seeds faces certain problems. The present research was designed to study the promotion of the germination of loquat seeds by moist-chilling and GA3 applications. The results showed that loquat seeds display an endogenous dormancy that can be released by moist-chilling treatment for a certain period. In this respect, the best treatment was moist-chilling for 3 weeks at 5 ± 1 °C or 1 week of moist-chilling followed by soaking in 250 ppm GA3 solution for 20 h. These treatments significantly increased germination percentage (88 and 85%, respectively) and decreased time to 50% germination (T50) (31.5 and 40.7 days, respectively) compared to control (51% and 56 days, respectively). Also, the characteristics of the obtained seedlings were much better than the control seedlings. In addition, the 3-week moist-chilled seeds contained the highest soluble protein concentration and were characterized by the synthesis of new protein band of 161.7 kDa that was absent in all other treatments. This treatment lead to the absence of five polypeptides bands (222.5, 201.5, 109.5, 71.1 and 49.3 kDa), which were synthesized in GA3 treatment, and the presence of a higher number of polypeptide bands compared with those of other moist-chilling periods and the control treatments. However, increasing the moist-chilling period over 3 weeks significantly decreased both germination percentage and T50. The combination between GA3 and moist-chilling treatments produced differential effects on seed germination, soluble protein and the number of protein bands depending on the length of the moist-chilling period. Although GA3 application on un-chilled seeds resulted in more synthesis of protein bands than other tested treatments, it did not improve the germination process. The concentration of soluble inorganic phosphorus of the tested seeds was negatively (r = −0.57*) and the concentration of soluble organic phosphorus positively (r = +0.49*) correlated with the germination percentage. It was concluded that treatment of moist-chilling for 3 weeks or 1 week moist-chilling followed by 250 ppm GA3 is recommended for promoting the germination process of loquat seeds and improving growth characteristics of the subsequent seedlings.  相似文献   

20.
《Scientia Horticulturae》2001,89(3):207-215
This study aimed to improve in vitro shoot proliferation efficiency without inducing hyperhydricity in Japanese pear. The shoot number increased at 2.5–10.0 mg l−1 benzyladenine (BA), while shoot fresh mass increased at 1.0 and 2.5 mg l−1 BA. Different macroelement formulation did not affect shoot proliferation, but adding activated charcoal (AC) to the medium inhibited markedly the production of axillary shoots and biomass and many shoots were hyperhydric. Different carbon sources (CS) significantly increased the shoot number and fresh mass, with the best results for shoot proliferation at 20–30 g l−1 sorbitol. With gelling agents, the shoot number increased at 0.4 and 0.6% agar and 0.3% gellan gum, while fresh mass increased at 0.4% agar. The hyperhydric explants were more than 30% at 0.4–0.6% agar and at any concentration of gellan gum. The improved culture (woody plant (WP) supplemented with 20 g l−1 sorbitol, 0.1 mg l−1 3-indolyl-butyric acid (IBA), 2.5 mg l−1 BA and 0.8% agar) and double-phase culture (the same medium using a double-phase liquid-gelling agent solidified culture system) produced a higher number of axillary shoots than the conventional culture (1/2MS supplemented with 0.1 mg l−1 IBA, 1.0 mg l−1 BA, 30 g l−1 sucrose and 0.8% agar), moreover, double-phase culture had a higher fresh mass than the other cultures.  相似文献   

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