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1.
The effects of differential soil crusting, as achieved by varying the raindrop size, and depth of sowing on seedling emergence
of chickpea (Cicer arietinum L.), pigeonpea (Cajanus cajan L.) and pearl millet (Pennisetum typhoides L.) were investigated. Three drop diameters: 2.75, 1.65 and 0.93 mm and four depths of sowing: 2, 4, 6, and 8 cm were studied.
Mean time of emergence increased with increase in raindrop size and depth of sowing. Crops differed in their emergence capacity
under adverse soil conditions from delay in the emergence of chickpea to complete failure in the case of pigeonpea. Pearl
millet was not significantly affected by drop size but was found to be sensitive to depths beyond 4 cm. Within the chickpea
crop, the variety H 208 was observed to have better emergence qualities than Pusa 209. Other parameters like epicotyl diameter,
swelling index, and the area of crust broken by the emerging seedling were measured. 相似文献
2.
M. J. van Steenis K. A. M. H. El-Khawass 《Entomologia Experimentalis et Applicata》1995,76(2):121-131
Life table data forAphis gossypii Glover (Homoptera: Aphididae), an important pest in glasshouse cucumber crops, were studied at 20, 25 and 30°C on two cucumber
cultivars (Cucumis sativus L.) in controlled climate cabinets. The development time on the cucumber cv. ‘Sporu’ ranged from 4.8 days at 20°C to 3.2
days at 30°C. Immature mortality was approximately 20% and did not differ between temperatures. Most mortality occurred during
the first instar. Reproduction periods did not differ among temperatures, but at 25 and 30°C more nymphs were produced (65.9
and 69.8 nymphs/♀, respectively) than at 20°C (59,9 nymphs/♀) because of a higher daily reproduction. Intrinsic rate of increase
was greatest at 25°C (r
m
=0.556 day−1). At 20 and 30°C the intrinsic rate of increase was 0.426 and 0.510, respectively. On cv. ‘Aramon’, the development time
ofA. gossypii was approximately 20% longer at all temperatures. Immature mortality did not differ between the two cultivars. The intrinsic
rate of increase on cv. ‘Aramon’ was 15% smaller than on cv. ‘Sporu’. The use of cucumber cultivars partially resistant to
aphids is discussed in relation to biological control of cotton aphid in glasshouses. Development time and immature mortality
on leaves of the middle and upper leaf layer of glasshouse grown cucumber plants (cv. ‘Aramon’) were comparable to development
in the controlled climate cabinets. On the lower leaves immature mortality was much higher (approximately 82%) than on leaves
of the middle (24.0%) and upper leaf layer (24.5%). Reproduction was less on the lower leaf layer (45.9, 70.5 and 70.1 nymphs/♀
on leaves of the lower, middle and upper leaf layer, respectively).
Aphids, successfully parasitized byAphidius colemani Viereck (Hymenoptera: Braconidae) only reproduced when they were parasitized after the third instar. Fecundity was 0.1 to
0.9 and 10.5 to 13.3 nymphs/♀ for aphids parasitized in the fourth instar or as adults, respectively. Reproduction of aphids
that were stung but survived the attack was lower than for aphids not stung. Average longevity of these aphids was equal to
the longevity of aphids not stung byA. colemani. 相似文献
3.
The marcoalga Ulva pertusa was cultured under (20 ± 2)°C, (20 ± 4)°C, (20 ± 6)°C, (20 ± 8)°C and (20 ± 10)°C circadian rhythms of fluctuating temperature
conditions, and constant temperature of 20°C was used as the control. The growth rate of macroalga at (20 ± 2)°C, (20 ± 4)°C
and (20 ± 6)°C were significantly higher than that at constant temperature of 20°C, while growth rate at (20 ± 8)°C and (20
± 10)°C were significantly lower than that at constant temperature of 20°C. The growth rate of macroalga was a quadratic function
of the thermal amplitude. Such a growth model can be described by G = β
0 + β
1(TA) + β
2(TA)2, where G represents the relative growth rate, TA is thermal amplitude in degree Celsius, β
0 is the intercept on the G axis, and β
1 and β
2 are the regression coefficients. The optimal thermal amplitude for the growth of thallus at mean temperature of 20°C was
estimated to be ± 3.69°C. Analysis of biochemical composition at the final stages of thaulls growth revealed that diel fluctuating
temperature caused various influences (P < 0.05). The content of chlorophyll, protein and total solute carbohydrate at (20 ± 2)°C and (20 ± 4)°C were slightly higher
than those at constant temperature of 20°C, however no statistically significant differences were found among them (P > 0.05). While osmolytes (total solute carbohydrate and free proline) at (20 ± 10)°C were significantly higher than that at
20°C (P < 0.05). Therefore, more chlorophyll and carbohydrate production might account for the enhancement in the growth of macroalga
at the diel fluctuating temperatures in the present study.
Handling editor: S. M. Thomaz 相似文献
4.
Germination responses ofMallotus japonicus (Thumb). Muell. Arg. seeds to temperature revealed a gap-detecting mechanism in the seed germination of the species. Among
various constant and alternating temperatures examined in the range from 12–40°C, only very limited temperature regimes were
found to be favourable for seed germination, specifically, alternating temperatures between 18–32°C and 28–40°C. A single
several-hour higher-temperature (32–40°C) treatment could also induce the germination of seeds which had been imbibed for
several days at a constant temperature in the range of 20–26°C, suggesting that there is a process requiring higher temperature
among the overal germination processes. Seeds located at or near the surface of denuded soil would have a good chance of experiencing
such a temperature change when several rainy days are followed by fine weather, while seeds beneath close vegetation would
not. On the other hand, the pressence or absence of light or a simulated ‘canopy ligh’ had little effect on the germination.
Therefore, it was concluded that the seeds ofM. japonicus have a ‘gapdetecting mechanism’ in the form of a higher-temperature requirement of a certain process involved in the overall
germination processes. 相似文献
5.
V. A. Zaslavski K. B. Zinovjeva S. Ya. Reznik T. Ya. Umarova 《Entomologia Experimentalis et Applicata》1995,74(2):99-104
The dynamics of adult eclosion inTrichogramma evanescens Westw. were studied under (1) constant light and temperature of 20 °C, (2) photoperiods L12:D12 and L16:D8 at 20 °C, (3)
thermoperiod 4 h 27 °/20 h 20 °C at constant light, (4) joint action of photo- and thermoperiod. The emergence was arhythmic
in constant light combined with constant temperature, while a sharp monophasic rhythm was observed with the isolated action
of photo- or thermoperiod. The ‘light-on’ and ‘temperature step-up’ signals were shown to act in one direction. When both
signals were combined, they manifested themselveses competing entraining stimuli which, in turn, revealed an apparent individual
variation in relative reactivity to the light and temperature signals. Some perspectives which follow from these observations
are discussed. 相似文献
6.
Development, survival, fecundity, progeny sex ratio (PSR) and age-specific life-table parameters of the parasitoid Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae) were examined at six different constant temperatures (12, 17, 22, 27, 32 and 37°C) in
the laboratory [70 ± 10% RH and 10:14 h (light:dark) photoperiod]. Second instar larvae of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) were reared on chickpea (Cicer arietinum L.) and used as the host. Development times shortened as the temperature increased from 12 to 37°C. The estimated lower developmental
threshold (tL) was 3.4°C. The thermal summation for total immature stages was 379.97 degree-days. A reciprocal relationship between temperature
and longevity was observed in the range of 12–17°C. The maximum mortality of pupae (71.8%) occurred at 37°C. At 22°C, the
yield of a female parasitoid averaged 137.3 ± 14.7 (mean ± SD) progeny, of which 89.6 ± 7.6 were daughters. The number of
daughters produced decreased when the females were kept either above or below 22°C, although the PSR was female biased in
the range of 17–27°C. The analyses of life-table parameters, developmental rates, reproduction, mortality and PSR suggest
that maximum population growth (r
m
) is near 27°C. There was little variation observed in most of the desired qualities of C. chlorideae in the range of 17–27°C, and it appears that the parasitoid is adapted to a wide range of temperatures. We suggest that for
maximum production the parasitoid should be reared at 22 ± 4°C and be released in areas where the temperature ranges between
17° and 27°C, as in the plains of northern India. 相似文献
7.
In vitro screening for cold hardiness of raspberry cultivars 总被引:1,自引:0,他引:1
Raspberry (Rubus idaeus L.) cultivars ‘Festival’, ‘Titan’ and ‘Willamette’ were cultured in vitro on three different media:
(A) MS medium supplemented with 1.0 mg l-1 BAP and 0.1 mg l-1 IBA, (B) MS medium without growth regulators, and (C) MS medium with reduced sucrose (10 g l-1), and exposed to different low temperature acclimation treatments: (1) control, no acclimation, (2) 1 week at +15 °C, 1 week
at +2 °C, 24 h at -2 °C and 3 days at +2 °C, and (3) 2 weeks at +15 °C, 2 weeks at +2 °C, 24 h at −2 °C and 3 days at +2 °C.
After acclimation, shoot moisture content was measured, and cold hardiness (LT50) was determined by controlled freezing. Shoot moisture content was generally lower on culture medium B compared to the other
media, but not affected by acclimation treatment. In non-acclimated plants, medium composition had no effect on cold hardiness
and no cultivar differences in hardiness were observed. After acclimation, plants on culture medium B were on average more
cold hardy than on the other media. Acclimation treatment 3 on media A and B allowed the best discrimination between the hardy
cultivar ‘Festival’ and less cold hardy ‘Titan’ and ‘Willamette’. When acclimation treatments were tested further using 11
raspberry cultivars with different levels of cold hardiness, discrimination between cultivars was satisfactory only after
acclimation treatment 3 on culture medium B.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
S. Jayasankar Marilyn Van Aman Zhijian Li Dennis J. Gray 《In vitro cellular & developmental biology. Plant》2001,37(4):476-479
Summary Somatic embryos of grapevine (Vitis vinifera L.) ‘Chardonnay’ were produced from liquid suspension cultures. Mature somatic embryos were blot dried briefly in the laminar
flow hood and germinated directly in Magenta GA-7 Vessels™ containing one of the following potting media: (1) sand, (2) commercial potting mixture (CPM), or (3) CPM overlaid with sand.
Each vessel containing 20 ml of distilled water and the potting medium was sterilized by autoclaving for 30 min and cooled
overnight before inoculating the somatic embryos. Five somatic embryos were placed in each vessel under aseptic conditions.
The vessels were closed and incubated at 26±2°C, 16 h photoperiod at 75 μmol s−1 m−2 light intensity. Results revealed that CPM overlaid with sand was best for plant development. There was more contamination
of somatic embryos on pure CPM. Since direct seeding bypasses at least two subcultures in agar medium, it has implications
for use of somatic embryos as ‘synthetic seeds’ for clonal plant production. This study shows that somatic embryos of grapevine
can be handled with some of the convenience of seeds, emphasizing the feasibility for further automating in vitro plant production, which might be especially useful for new varieties where propagation material is limited. 相似文献
9.
Fotini G. Skiada Katerina Grigoriadou Eleftherios P. Eleftheriou 《Central European Journal of Biology》2010,5(6):839-852
The effects of six basal media on in vitro shoot proliferation of the greek grapevines Vitis vinifera L. cv. ‘Malagouzia’ and ‘Xinomavro’ were investigated. Galzy and Zlenco proved to be the most effective for ‘Malagouzia’
and ‘Xinomavro’, respectively. If only BA was present in the medium, shoot development was poor and the plantlets were chlorotic.
When the medium was supplemented with BA and NAA, growth was enhanced. The best ratio (in μM) of growth regulators was 0.5/0.3
for ‘Malagouzia’, and 0.1/0.03 for ‘Xinomavro’, which resulted in the highest number of microshoots per explant and greatest
proliferation rate. The development of ‘Malagouzia’ and ‘Xinomavro’ explants at 21±2 and 26±2°C was also investigated, revealing
the higher temperature to be more effective. Regarding rooting, 0.5 μM IBA improved root formation at 26°C for ‘Malagouzia’
and 0.5 μM IBA at 21°C for ‘Xinomavro’. Moreover, 0.5 μM IBA resulted in a higher rooting percentage (>95%) and proved to
be more beneficial for the overall morphological appearance of the plantlets of ‘Malagouzia’. After acclimatization, survival
of microshoots cultivated in media with IBA was higher than those in NAA. 相似文献
10.
Cultures of the blue-green alga (cyanobacterium)Oscillatoria tenuis were used to simulate thermal degradation and gas formation by heating without oxygen at 250° and 350 °C for 100 h. Analysis
through gas chromatography showed that the gases were mainly CH4, C2H6, C3H8, iC4 (isobutane), nC4 (normal butane), iC5 (isopentane), nC5 (normal pentane), H2, C02 and N2. The volume of gases per g dry weight of alga was 44 ml at 250 °C and 100 ml at 350 °C. Alkane gas comprised only 2.04% of
the total at 250 °C and rising to 40.0% at 350 °C. The fraction of C02 decreased from 83.3% at 250 °C to 40.0% at 350 °C. The quantity of alkane in the soluble organic matter doubled with rising
temperature but the H/C atomic ratio in the ‘kerogen’, insoluble organic matter, decreased sharply. Infrared spectra of the
‘kerogen’ showed that the peak of adipose radical at 2900 cm−1 disappeared gradually with rising temperature, which reflects the gradual break of CH4 or C2H6 from ‘kerogen’. This demonstrates that insoluble organic matter rather than soluble organic matter in blue-green algae are
the main sources of the gas alkanes in the process of simulated thermal degradation. 相似文献
11.
Dong Cao Wensheng Hou Shikui Song Hongbo Sun Cunxiang Wu Yongsheng Gao Tianfu Han 《Plant Cell, Tissue and Organ Culture》2009,96(1):45-52
Agrobacterium rhizogenes-mediated transformation has become a powerful tool for studying gene function and root biology due to its quick and simple
methodology. This transformation method is particularly suitable for those plants, including legumes, whose transformation
using Agrobacterium tumefaciens has been challenging. Although there are some reports on A. rhizogenes-mediated transformation of legumes to produce ‘composite’ plants, conditions influencing A. rhizogenes-mediated transformation of soybean [Glycine max (L.) Merr.] have not been yet fully investigated. To better understand A. rhizogenes-mediated root transformation in soybean, we have evaluated the impact of genotype, plant age for infection, bacterial inoculating
concentration, inoculation temperature, and other factors on transformation of soybean. The results have shown that there
are significant differences among soybean genotypes in their susceptibility to A. rhizogenes. Soybean cv. Zigongdongdou is the most susceptible to A. rhizogenes strain K599 among 10 genotypes tested. The effects of seedling age have been evaluated, and 1-day-old plantlets are found
to be optimal for hairy root induction. There are no significant differences in hairy root induction for bacterial suspension
from OD600 = 0.2 to OD600 = 1.2. Under 16 h photoperiod, hairy roots can be induced both at 23°C/20°C and 28°C/25°C, but not at 33°C/30°C as day/night
temperature regimes. Using this transformation protocol, almost 100% of the composite plants formed hairy roots within 2 weeks,
and based on GUS histochemical analysis, 94.2% transformation frequency is obtained. Transgene integration has been also confirmed
by Southern blot analysis.
D. Cao and W. Hou contributed equally to this work. 相似文献
12.
A landrace (‘Moscatella’) and a commercial cultivar (‘Starkspur Red’) of Malus pumila Mill. were maintained and proliferated in vitro for ≥ four years. A factorial experiment, planned to evaluate the response of the two cultivars in conservation in determined
slow growth conditions, was carried out for eighteen months. Single node cuttings were stored in 4 different media, at 4 °C,
in dark conditions, in microvessels to assess the feasibility of reducing space in in vitro gemplasm banks. Culture viability after storage was evaluated after 6, 8,12 and 18 months of storage. Both varieties showed
high survival percentages for up to a year of conservation, but the landrace's capability to resume growth dropped dramatically
afterwards. On the contrary, ‘Starkspur Red’ maintained substantially unchanged capacity of resuming vigorous growth after
18 months of conservation. Overall, microvessels appeared to be suitable for storing single node cuttings under slow growth
conditions up to a year at least. The described techniques could be useful for in vitro germplasm collections where frequent subculturing enhances the risk of genetic changes and personnel, energy and materials
costs limit the amount of genotypes that can be managed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
13.
Csaba Lantos Anikó Gémes Juhász György Somogyi Krisztina Ötvös Pál Vági Róbert Mihály Zoltán Kristóf Norbert Somogyi János Pauk 《Plant Cell, Tissue and Organ Culture》2009,97(3):285-293
The influence of the developmental stage of microspores on establishing isolated microspore cultures of three Hungarian (‘Szegedi
80’, ‘Szegedi 178’, and ‘Remény’) and three Spanish (‘Jeromin’, ‘Jariza’, and ‘Jaranda’) pepper genotypes was investigated.
Donor anthers containing 80% uninucleated and 20% binucleated microspores yielded the highest frequency of successful microspore
cultures. Co-cultures with wheat, line ‘CY-45’, ovaries exhibited enhanced frequency of embryoid production than those with
pepper ovaries. Differences in efficiency of isolated pepper microspore culture establishment were observed among different
pepper genotypes. Green plantlets were regenerated from microspore-derived embryoids, but some were exhibited abnormal growth
habits, such as leaf rosetting. A total of seven fertile microspore-derived plants were obtained, including three ‘Jariza’,
three ‘Jaranda’, and a single ‘Szegedi 80’ plant. 相似文献
14.
Dietary fibres from Ulva lactuca (L.) Thuret (sea lettuce) and Enteromorpha compressa (L.) Grev. (A.O. nori) were measured according to a ‘standard’ method and a ‘physiological’ protocol simulating the gastric
and intestinal environments. U. lactuca contained 15.8–8.0% soluble and 24.2–32.6% insoluble fibres according to the ‘standard’ and ‘physiological’ methods, respectively.
For E. compressa, these values were 14.9–15.9 and 21.6–28.7%, respectively. For both algae, the composition suggests that the soluble fibres
were xylorhamnoglycuronans sulphates and insoluble fibres were essentially composed of glucans. No marked chemical compositional
variation was observed between soluble fractions extracted under the simulated gastric and intestinal conditions. Fibres in
both algae are hydrophilic but the water holding capacities were higher after extraction of soluble fibres (5.5–9.5 g g−1 for the dry algae; 14.0–16.0 g g−1 for the standard insoluble fibres). Water soluble fibres demonstrated low intrinsic viscosities at 37 °C in buffers, particularly
those from E. compressa (36.0–36.5 ml g−1), and was affected by pH for those of U. lactuca (147.5 ml g−1 at pH 3.0 and 175.0 ml g−1 at pH 7.3). 相似文献
15.
M. Aluja R. J. Prokopy J. P. Buonaccorsi R. T. Cardé 《Entomologia Experimentalis et Applicata》1993,68(2):99-108
Little is known about how adults of the corn leafhopper,Dalbulus maidis (DeLong & Wolcott), and its congeners survive subfreezing temperatures at high elevations during the dry winter in Mexico.
In the laboratory, duration of survival at −5°C was measured for four MexicanDalbulus species:D. maidis, D. elimatus (Ball),D. gelbus DeLong andD. quinquenotatus DeLong & Nault; and a closely related North American species,Baldulus tripsaci Kramer & Whitcomb. Adult leafhoppers reared under environmental conditions that simulated the beginning of the dry winter
season during October in Mexico (‘October-reared’) were at least twice as tolerant of −5°C than adults reared under environmental
conditions that simulated the beginning of the wet summer season during June (‘June-reared’).Dalbulus species found primarily at high elevations, such asD. elimatus, were seven times more tolerant of −5°C thanD. quinquenotatus, a species which overwinters at low to mid elevations on itsTripsacum hosts. October-rearedD. maidis adults survived relatively short periods at −5°C (LT50=8.9h) compared to October-rearedD. elimatus adults (LT50=42.3h). This suggests that in Mexico,D. maidis either overwinters in protected habitats at higher elevations or it migrates to lower, frost-free regions. October-rearedB. tripsaci adults, which overwinter in the egg stage, were intolerant of −5°C (LT50=2.6h). A conditioning period for 1 h at +5°C before and after exposure to −5°C significantly improved survival forD. maidis. Supercooling points (SCPs) were between −23 and −20°C, indicating that mortality of these leafhoppers at −5°C was due to
cold shock injury rather than internal ice formation. 相似文献
16.
Qinxian Jia Hongping Wang Fanjing Kong Mianping Zhen 《Frontiers of Biology in China》2009,4(3):358-363
The effects of temperature on population characteristics of Artemia parthenogenetica Gahai from the Gahai Salt Lake, Qinghai Province, China, were studied in the laboratory at a salinity of 60‰. The major conclusions
are as follows: (1) It was found that the adaptive temperature for the development of brine shrimp ranged from 10°C to 39°C.
The threshold temperature of development (TD) and the effective accumulative temperature (TA) for hatching were 9.94°C·d and
(22.91±2.08)°C·d, respectively. The TD and TA for the larva were 10.33°C·d and (261.26±24.1)°C·d, respectively, and for the
whole generation were 10.28°C and (458.68±57.60)°C·d, respectively. (2) It showed that the population’s net reproduction rate
(Ro), the intrinsic rate of natural increase (rm), the mean generation time (T), the finite rate of increase (λ), and the days for population to double (t) of the brine shrimp
were determined over temperatures ranging from 19°C to 34°C by analyzing the life table and numerical model. In the temperature
range of 14.3°C to 37.3°C for Ro>1, the optimum temperature (°C) for Ro, rm, λ, and t were 25.8°C, 29.8°C, 30.5°C, and 29.02°C, respectively. The maximum values of Ro, rm and λ were 54.86 ind., 0.106138/d, and 1.1070/d, respectively. The minimum value of t was 4.73 d. The value of T was in a
range of 96.77 to 16.10 d. (3) Based on the 1993–1994 and 1997 data of the water temperature in the Gahai Salt Lake, Qinghai
Province, it was estimated that the number of generation of A. parthenogenetica Gahai and the number of the reproductive peak value were 2.67±0.34 and 4.69±0.43 in a year, respectively. The peak of nauplii of
the first generation was on April 20 to 28. The last whole generation began on August 10. The first reproductive peak was
on June 18 to 25. The last reproductive peak was on September 12 to 17. The nauplii that hatched after September 1 cannot
complete the development from nauplii to adults because of insufficient habitat effective accumulative temperature. During
the period from July 11 to September 20, there was a relatively high productivity of the population. In this case, doubling
the population would take less than 30 d, and the intrinsic rate of natural increase was over 0.02/d. Therefore, the value
of resource exploitation would be maximal during that period annually. 相似文献
17.
Trabelsi El Bahri Bouzid Sadok Bouzid Monji Elloumi Nedra Belfeleh Zina Benabdallah Abdallah Ghezel Rachida 《Journal of Plant Biology》2003,46(3):173-180
We induced somatic embryogenesis from the cotyledon segments ofOlea europaea (L) cvs. ‘Chetoui’, ‘Chemleli’, and ‘Arbequina’. Calli were established from all three cultvars on OMc media supplemented
with IBA and 2i-R The greatest success was obtained with media that contained zero or low concentrations of growth regulators.
High levels of hormones (i.e.,>0.5 mgL-1 IBA and 2i-P) inhibited embryogenesis. Embryos at different maturation stages were observed with continuously proliferating
secondary embryogenesis. Abnormally shaped embryos and teratoma were also noted. Four weeks was the optimal incubation period
for inducing embryogenesis on the auxin-containing medium. In addition, 30 to 40 gL-1 sucrose was more effective than glucose in stimulating the growth and maturation of somatic embryos. Embryogeic efficiency
was also higher when multivariate combinations of nitrogen sources (inorganic and organic nitrogen forms) were used. The plantlets
that were derived from our germinating somatic embryos were similar to those obtained from axillary buds. 相似文献
18.
The effects of three salinities (0, 100 and 500 mM NaCl) and four constant temperatures (10, 20, 30 and 35 °C) on seed germination of Halostachys caspica (M. B.) C. A. Mey., Kalidium foliatum (Pall.) Mop. and Halocnemum strobilaceum (Pall.) Bieb. were investigated. After seeds were treated with different concentrations of NaCl at constant temperatures
of 10–35 °C for 16 days, ungerminated seeds were transferred to distilled water for 10 days to investigate the total germination;
after this time, the ungerminated seeds from the 10 and 20 °C treatments were then moved to 35 °C for another 5 days to determine
the final germination. The three plant species in the present experiment are salt-resistant euhalophytes growing in high saline
soils in the Zhungur Basin in Xinjiang, a northwest province of China.Compared with germination under control conditions,
germination percentages of all three species were not affected by 100 mM NaCl at 10–35 °C, while severely inhibited by 500 mM NaCl; germination percentages were very low at 10 °C up to 100 mM NaCl for all species; the optimum temperature for germination of H. caspica and K. foliatum was 20–30 °C, while 35 °C for H. strobilaceum, up to 100 mM NaCl; seeds did not suffer ion toxicity for all species, as evidenced by the high total germination after ungerminated seeds
pretreated with 500 mM NaCl were transferred to distilled water at constant temperatures of 10–35 °C for 10 days, and the high final germination
after the ungerminated seeds from the 10 and 20 °C treatments were subsequently moved to 35 °C for another 5 days; Halostachys caspica had greater sensitivity to increasing temperatures from 10 and 20 °C to 35 °C compared with the other two species. 相似文献
19.
Nielsen P Larsen LH Ramløv H Hansen BW 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2007,177(3):287-296
The oxygen consumption rate during embryogenesis of Acartia tonsa subitaneous eggs were measured at different temperatures (10, 15, 17, 21, 24 and 28°C) with nanorespirometry. The oxygen
consumption was constant during the embryogenesis but increased rapidly at hatching time. The mean ± SD oxygen consumption
rate increased exponentially with temperature and ranged from 0.09 ± 0.04 (10°C) to 0.54 ± 0.09 nmol O2 egg−1 h−1 (28°C). The mean ± SD Q10-value was 2.51 ± 0.15. Calculations of energy consumption during embryogenesis ranged from 1.86 to 18.28 mJ depending on
temperature and development time. We conclude that the effect of temperature on oxygen consumption rate was far less important
than the prolonged development time when calculating the energy consumed during embryogenesis. 相似文献
20.
Summary Shoot tips, of four potato cultivars (Désirée, Genet, Tigoni, and Tomensa), 3–4 mm in size, were precultured for 2 d on Murashige
and Skoog (MS) solid medium, then encapsulated in calcium alginate to produce hollow bead synthetic seed capsules averaging
0.78 cm in diameter. Regeneration and ‘regrowth’ were tested on MS solid medium and on soil in the greenhouse, respectively.
The encapsulated shoot tips were stored at 4 and 10°C for up to 390 d. For all cultivars, the encapsulated shoot tips stored
at both temperatures for 180 d and at 4°C,for 270 d, 100% regeneration on MS solid medium was recorded. After 360 d in storage
at 4°C, 70.8% (Tigoni), 66.7% (Genet), 58.3% (Désirée), and 51.5% (Tomensa) regeneration was recorded on MS medium, reducing
to 15% (Tigoni), 25% (Genet), 10% (Désirée), and 0% (Tomensa) regeneration after 390 d in storage. ‘Regrowth’ of 93–100% was
recorded for non-stored encapsulated shoot tips, directly transferred on soil in the greenhouse after a 2 wk preculture on
MS solid medium with an added fungicide (carbendazim) in the encapsulating gel. The ‘regrown’ shoot tips produced plants showing
normal development. The results presented here demonstrate that hollow bead synthetic seed capsules are an alternative propagating
method for potato seed production. 相似文献