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1.
Gerald Kastberger Ronald Thenius Anton Stabentheiner Randall Hepburn 《Journal of Insect Behavior》2009,22(1):65-85
Colony defence in Apis mellifera involves a variety of traits ranging from ‘aggressive’ (e.g. entrance guarding, recruitment
of flying guards) to ‘docile’ (e.g. retreating into the nest) expression. We tested 11 colonies of three subspecies (capensis, scutellata, carnica) regarding their defensiveness. Each colony was selected as reportedly ‘aggressive’, ‘intermediate’ or ‘docile’ and consisted
of about 10,000 bees. We applied three stimulation regimes (mechanical disturbance, exposure to alarm pheromones, and the
combination of both) and measured their behaviours by tracking the rates of outflying bees at the entrance sites of the test
hives. We provided evidence that for mechanical disturbances the test colonies resolved into two response types, if the ‘immediate’
defence response, assessed in the first minute of stimulation, was taken as a function of foraging: ‘releaser’ colonies allocated flying guards, ‘retreater’ colonies reduced the outside-hive activities. This division was observed irrespective
of the subspecies membership and maintained in even roughly changing environmental conditions. However, if pheromone and mechanical
stimulation were combined, the variety of colony defensiveness restricted to two further types irrespective of the subspecies
membership: six of nine colonies degraded their rate of flying defenders with increasing foraging level, three of the colonies
extended their ‘aggressiveness’ by increasing the defender rate with the foraging level. Such ‘super-aggressive’ colonies
obviously are able to allocate two separate recruitment pools for foragers and flying defenders. 相似文献
2.
Germination responses ofRhus javanica L. seeds to temperature and light were investigated with special reference to their gap-detecting mechanisms in germination,
i.e., responses to elevated and/or fluctuating temperatures and sensitivity to leaf-canopy transmitted light. The seeds, which
have water-impermeable coats to prevent imbibition, were shown to become permeable and germinable after exposure to higher
temperatures of 48–74°C for a brief period depending on the temperature. Once the coat impermeability had been removed by
such heat treatment, the seeds became readily germinable over a wide range of temperature and light conditions. The lower
and higher temperature limits for germination were around 8° and 36°C, respectively, with an optimal temperature of around
25°C. Simple linear relationships were observed between the temperature and germination rates, i.e., the reciprocals of the
time taken by the seed subpopulations to show 10–70% germination in the sub-optimal temperature range, where the required
‘thermal time’ for germination was 2300–3600 Kh. The presence or absence of light or a simulated ‘canopy light’ had little
effect on the germination of this species. It was concluded that the seeds ofR. javanica are furnished with a gap-detecting mechanism in the form of a heat requirement for the breakage of water-impermeable seed
dormancy, which may be fulfilled by either daytime elevation of the surface temperature of exposed soil, or more effectively
by fire. 相似文献
3.
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
4.
Experiments were conducted to quantify parasitism of Colorado potato beetle,Leptinotarsa decemlineata (Say), by the egg parasitoid,Edovum puttleri Grissell, on 3 different cultivars of eggplant,Solanum melongena L. Levels of parasitism were higher (P<0.05) on ‘Black Pride’ than on other cultivars. The percentage of egg masses that
were parasitized was 1.2-fold higher (P<0.05) on ‘Black Pride’ than on ‘Harris Special’ and ‘White’. The number of eggs per
mass that were parasitized was 1.3- and 1.4- fold greater (P<0.05) on ‘Black Pride’ than on ‘Harris Special’ and ‘White’,
respectively. The percentage of eggs that were parasitized per mass and percentage of emerged adult parasitoids did not differ
(P>0.05) among cultivars; between 2.1- to 2.6- fold more females than males emerged from eggs on all cultivars during the
growing season.Edovum puttleri suppressed the 2nd generation ofL. decemlineata on ‘Black Pride’ and ‘Harris Special’, but did not suppress populations on ‘White’.
相似文献
5.
Haoru Tang Zhenglong Ren Gari Krczal 《In vitro cellular & developmental biology. Plant》2000,36(1):47-50
Summary Well-developed somatic embryos were selected from a repetivively somatic embryo line derived from embryonic axes of immature
zygotic embryos of English walnut ‘No. 120’ (Juglans regia L.) for germination and conversion studies. In germinating dishes, somatic embryos germinated into only shoots, only roots,
or both shoots and roots. Without any pretreatment, 28% somatic embryos germinated, while those treated with 2.5–5.0 mg 1−1 (7.2–14.4 μmol) gibberellic acid (GA3) germinated at 25–28% and those receiving a cold treatment of 2–3 mo. at 3–4°C germinated at 30–43%. However, only 4–19%
of the germinating embryos showed both shoots and roots. Treated with desiccation, either with CaCl2·6H2O or Ca(NO3)2·4H2O at 20°C in the dark for 3 d, somatic embryos germinated at 85–91%, 57–69% of which had both shoots and roots. Treatment
with 2 mo. cold storage in combination with desiccation using Ca(NO3)2·4H2O resulted in 92% of somatic embryos germinating, 70% of which showed both shoots and roots. No significant differences were
observed between solid and liquid germination media. After transferring the germinating embryos to plantlet development media,
52–63% of those with both shoots and roots developed into plantlets while 11% with only shoots or 9% with only roots converted
into plantlets. Plantlet development was improved by using lower medium salts and sucrose concentrations. The addition of
activated charcoal enhanced root development, particularly root branching. Of 131 plants transplanted, 91 plants were acclimatized
to a greenhouse. 相似文献
6.
Summary Use of lysozyme was tested for treatment of bacterial contaminations in in vitro shoot cultures of quince (Cydonia oblonga) ‘BA 29’ and the hybrid (Prunus persica × P. amygdalus) rootstock ‘GF 677’. Shoots which had been contaminated for about 1 yr by Bacillus circulans and Sphingomonas paucimobilis were treated in liquid culture, at pH 4.5, with 9–36 mg ml−1 egg white lysozyme (EWL), and compared to each other and to untreated cultures for their growth, proliferation, and number
of bacterial colony-forming units in the tissues. EWL did not negatively affect shoot growth up to 18 mg ml−1; furthermore, the proliferation rates of EWL-treated shoots were sometimes higher than those of controls. In contrast, the
concentration of 36 mg ml−1 had some deleterious effect on the regrowth capacity and shoot production of ‘GF 677’ at the first subculture to solid medium
after EWL, treatments. EWL had a simple bacteriostatic effect against Sphingomonas paucimobilis; in contrast, it was effective at 18 mg ml−1 in eliminating Bacillus circulans in both ‘BA 29’ and ‘GF 677’ cultures, after optimal treatment duration. 相似文献
7.
Effects of NaCl stress on germination, antioxidant responses, and proline content in two rice cultivars 总被引:1,自引:0,他引:1
Young Geol Sohn Byung Hyun Lee Kyu Young Kang Jeung Joo Lee 《Journal of Plant Biology》2005,48(2):201-208
We investigated the physiological and biochemical bases for salt tolerance in two rice (Oryza sativa L.) cultivars — relatively salt-tolerant ‘Dongjin’ and salt-sensitive ‘Kumnam’. Salinized hydroponic cultures were studied
at the germination and seedling stages. NaCI inhibited germination more severely in ‘Kumnam’ than in ‘Dongjin’. Increasing
the salt concentration also deterred growth to a larger extent in the former. Moreover, the leaves of ‘Kumnam’ exhibited greater
increases in lipid peroxidation and Na+ accumulation than those of ‘Dongjin’ under stress. The activities of constitutive and salt-induced superoxide dismutase (SOD,
EC 1.15.1.1) and ascorbate peroxidase (AP, EC 1.11.1.11) were also higher in ‘Kumnam’, while only catalase (CAT, EC 1.11.1.6)
activity was slightly higher in stressed plants of ‘Dongjin’. The positive correlation between leaf proline levels and NaCI
concentration was more evident in ‘Kumnam’. However, ‘Dongjin’ seeds, which had higher germinability in the presence of NaCI,
also contained more proline. These results suggest that the higher salt tolerance in ‘Dongjin’ seedlings could be ascribed
to their lower NaCI accumulations in the leaves. This presumably is due to reductions in the uptake or transport rates of
saline ions to the shoots from the roots. Finally, we believe that the higher germination rate by ‘Dongjin’ is caused by its
higher seed proline content. 相似文献
8.
Previous studies have tested the “vernal dam” hypothesis of spring ephemeral herbs in hardwood forests. The desert annual
is a component of the desert ecosystem that takes advantage of water resources and temperature conditions during the rainy
season to rapidly complete its life cycle within several months. To understand the role desert annual/ephemeral plants play
in nutrient flow, we studied vegetation cover, nitrogen content and litter production of annual plants and litter decomposition
rate in plant communities dominated by four shrubs (Haloxlon ammodendron, Hedysarum scoparium, Calligonum mongolicum, and Nitraria tangutorum) and two dominant annuals (Agriophyllum squarrosum and Halogeton arachnoideus Moq) in Minqin, northwestern China. Results indicate that over half of the total vegetation cover was provided by annuals.
Annuals also took up a large amount of nitrogen (0.46–3.78 g N m−2) along the oasis–desert ecotone. Litter production and nutrient content were higher in areas dominated by annual plants than
in areas dominated by shrubs. Furthermore, the litter decomposition rate of the annuals was higher than that of the shrubs,
except for the shrub H. ammodendron, although almost all of the litter’s carbon (C) and nitrogen (N) remained after 6 months of decomposition. Without the annuals,
more nutrients and rainwater might be lost through leaching or dust transfer caused by the wind erosion. In addition, green
twigs of the annuals are the food for some animals, we found some green twigs and litter from annuals left in front of gerbil
and rabbit burrows, sometimes even blocking these burrows. Thus, desert summer annuals, like nutrient reservoirs and providers,
take up nutrients during the rainy season, providing some animals and microbes with food, and finally release these nutrients
after death.
Bao-Ming Chen and Gen-Xuan Wang contributed equally to this work. 相似文献
9.
Li-Chun Huang Cheng-Kuo Hsiao Shu-Huey Lee Bau-Lian Huang Toshio Murashige 《In vitro cellular & developmental biology. Plant》1992,28(1):30-32
Summary Repeated grafting of 0.2-cm shoot tips from fruiting-age trees ofCitrus reticulata Blanco ‘Ponkan’ mandarin andC. sinensis Osbeck ‘Liu Tseng’ sweet orange onto freshly germinated ‘Troyer’ citrange [Poncirus trifoliata (L.) Raf. X.C. sinensis Osbeck] seedlings in vitro resulted in progressive restoration of rooting competence and vigor of regenerated roots and shoots.
The restored traits were retained through the course of the investigation and suggested a phase reversal phenomenon. 相似文献
10.
Cytokinins antagonize the jasmonates action on the regulation of potato (Solanum tuberosum) tuber formation in vitro 总被引:1,自引:0,他引:1
Debabrata Sarkar Suman Kumar Pandey Sushruti Sharma 《Plant Cell, Tissue and Organ Culture》2006,87(3):285-295
Cucurbita pepo L. (squash, pumpkin) is a highly polymorphic vegetable species of major importance. Our study characterized a spectrum of C. pepo germplasm for the ability to regenerate in vitro by direct organogenesis from cotyledon explants. Cultivars tested included both cultivated subspecies, texana and pepo, and nearly all of their respective cultivar-groups. Direct shoot regeneration occurred in all accessions, and was generally high (56–94%), with a single exception of 22% (‘Bolognese’). There was no significant difference between the percentage regeneration of the two subspecies. Shoot regeneration per responding explant was uniform (1.2–1.6 shoots per explant). Only ‘True French’ produced statistically more shoots (3.9 per explant) than other accessions. The morphology of regeneration varied. Most cultivars produced long shoots, often fasciated, amid a few small buds. Some subspecies pepo cultivars (Beirut, Yugoslavia 7, Ma’yan and True French) produced short, massive, hollow shoots, sometimes accompanied by shoots that were more normal. Two subspecies texana cultivars (Creamy Straightneck and Small Bicolor) produced single (sometimes double) shoots without other buds. The production of chimeric (mixoploid) regenerants varied and there was a tendency to regenerate chimeric plants from the widest-fruited accessions (i.e. lowest length-to-width ratio) in each subspecies. Subspecies pepo Pumpkin Group ‘Tondo di Nizza’ showed significantly greater production of chimeric regenerants. In comparison with the great range of variation observed in fruit shape, the variation of in vitro responses (mostly less than 2-fold in regeneration and shoot production) was less than expected. 相似文献
11.
Richard L. Bell Ralph Scorza Delores Lomberk 《Plant Cell, Tissue and Organ Culture》2012,108(2):229-236
Adventitious shoot regeneration of twenty-four pear genotypes was compared in a common in vitro shoot induction and development
protocol. This study also compared cultures newly established from scionwood with cultures that been in long-term cold storage.
In vitro cultures of 13 Pyrus genotypes and budwood from 23 Pyrus genotypes were obtained from the National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. With the exception of
one genotype of P. elaeagrifolia Pall., and ‘Ya Li’ (P. pyrifolia var. sinensis Teng & Tanabe), all were P. communis L. cultivars. The basal shoot induction media consisted of Chevreau and Leblay (CL) basal nutrients, vitamins, and organics
(Chevreau and Leblay in Acta Hortic 336: 263–268, 1993). The analysis of variance indicated that differences among genotypes were highly significant and the main effect of culture
origin was non-significant. However, there was a significant interaction between genotype and culture origin, with percentage
regeneration of ‘Abate Fetel’ from new budwood significantly greater than that from long-term in vitro cultures, while ‘Jesinji
Vodenac’ cultures derived from the old NCGR cultures regenerated significantly more adventitious shoots. The ranges of mean
regeneration frequency were similar for both in vitro (0–87.7%) and scionwood-derived cultures (0–70.7%). Maximum regeneration
was observed for ‘Conference’, followed by ‘Magness’, ‘Dr. Jules Guyot’, and Packham’s Triumph’. The range of number of adventitious
shoots was relatively narrow, with the minimum of 1.0 for seven genotypes to 2.2 for ‘Conference’. 相似文献
12.
Shimpei Uraguchi Masako Kiyono Takuya Sakamoto Izumi Watanabe Katsuji Kuno 《Planta》2009,230(2):267-276
The contributions of cadmium (Cd) accumulation in cell walls, antioxidative enzymes and induction of phytochelatins (PCs)
to Cd tolerance were investigated in two distinctive genotypes of black oat (Avena strigosa Schreb.). One cultivar of black oat ‘New oat’ accumulated Cd in the leaves at the highest concentration compared to another
black oat cultivar ‘Soil saver’ and other major graminaceous crops. The shoot:root Cd ratio also demonstrated that ‘New oat’
was the high Cd-accumulating cultivar, whereas ‘Soil saver’ was the low Cd-accumulating cultivar. Varied levels of Cd exposure
demonstrated the strong Cd tolerance of ‘New oat’. By contrast, low Cd-accumulating cultivar ‘Soil saver’ suffered Cd toxicity
such as growth defects and increased lipid peroxidation, even though it accumulated less Cd in shoots than ‘New oat’. Higher
activities of ascorbate peroxidase (EC 1.11.1.11) and superoxide dismutase (EC 1. 15. 1. 1) were observed in the leaves of
‘New oat’ than in ‘Soil saver’. No advantage of ‘New oat’ in PCs induction was observed in comparison to Cd-sensitive cultivar
‘Soil saver’, although Cd exposure increased the concentration of total PCs in both cultivars. Higher and increased Cd accumulation
in cell wall fraction was observed in shoots of ‘New oat’. On the other hand, in ‘Soil saver’, apoplasmic Cd accumulation
showed saturation under higher Cd exposure. Overall, the present results suggest that cell wall Cd accumulation and antioxidative
activities function in the tolerance against Cd stress possibly in combination with vacuolar Cd compartmentation. 相似文献
13.
Summary An efficient system to regenerate shoots on excised sepals (calyx) of greenhouse-grown ‘Bounty’ strawberry (Fragaria x ananassa Duch.) was developed in vitro. Sepal cultures produced multiple buds and shoots without an intermediary callus phase on 2–4 μM 1-phenyl-3-(1,2,3-thiadiazol-5-yl) urea (thidiazuron, TDZ)-containing shoot induction medium within 4–5 wk of culture initiation.
Young expanding sepals with the adaxial side touching the culture medium and maintained for 14 d in darkness produced the
best results. In a second experiment, sepals proved more effective than the leaf discs and petiole segments for regenerating
shoots. A third experiment compared the effects of six concentrations of two cytokinins (TDZ at 0, 0.5, 2, and 4 μM and zeatin at 2 and 4 μM) for elongation of sepal-derived adventitious shoots. The media containing TDZ generally promoted more callus formation and
suppressed shoot elongation. TDZ-initiated cultures transferred into the medium containing 2–4 μM zeatin, produced usable shoots after one additional subculture. Shoots were rooted in vitro in the same medium used for shoot regeneration, but without any growth regulators. When transferred to potting medium, 85–90%
of in vitro plantlets survived. 相似文献
14.
J. Y. Choi H. J. Kim C. H. Lee J. M. Bae Y. S. Chung J. S. Shin N. I. Hyung 《In vitro cellular & developmental biology. Plant》2001,37(2):274-279
Summary An efficient and simple plant regeneration system via organogenesis from leaf segments of persimmon (Diospyros kaki Thunb.) cultivars ‘Fuyu’ and ‘Nishimurawase’ has been developed. The regeneration capacity was influenced by the culture
vessels, gelling agents, plant growth regulators, and light conditions. Leaf explants taken from in vitro shoots were cultured on a modified Murashige and Skoog medium (MS1/2N), for 16 wk without transfer to fresh medium. Adventious
shoots appeared after 4 and 8 wk in culture of ‘Nishimurawase’ and ‘Fuyu’ tissues, respectively. The culture of leaf explants
in Erlenmeyer flasks with medium containing 4 g l−1 agar enhanced shoot formation in comparison to media with increased agar concentrations. Optimal shoot regeneration was obtained
with 5 mg l−1 (22.8 μM) zeatin and 0.1 mg l−1 (0.05 μM) indole-3-butyric acid (IBA) for ‘Nishimurawase’, and 10 mg l−1 (45.6 μM) zeatin and 0.1 mg l−1 (0.05 μM) IBA for ‘Fuyn’. Shoot regeneration frequencies in both cultivars were 100%, and shoot numbers per explant reached up to
9.2 for ‘Nishimurawase’ and 2.2 for ‘Fuyu’. Dark incubation during the first 4–5 wk was the most effective condition to successfully
influence shoot regeneration in both cultivars. While dark incubation was essential for adventitious shoot formation by ‘Fuyu’,
it was only slightly beneficial to ‘Nishimurawase’. More than 80% of the regenerated shoots rooted within 4 wk on hormone-free
MS1/2N demium after having been dipped for 30 s in 250 mg l−1 (1.1. mM) IBA solution. 相似文献
15.
Effects of exogenous B supply on growth, B accumulation and distribution of two navel orange cultivars 总被引:3,自引:0,他引:3
Ou Sheng Shang W. Song Yun J. Chen Shu A. Peng Xiu X. Deng 《Trees - Structure and Function》2009,23(1):59-68
To investigate the effects of boron (B) on growth, B concentration and distribution of two navel orange cultivars, ‘Newhall’
(Citrus sinensis Osbeck) and ‘Skagg’s Bonanza’ (Citrus sinensis Osbeck) grafted on the rootstock trifoliate orange [Poncirus trifoliata (L.) Raf.], B at five levels was exogenously supplied to 1-year-old grafted plants of both cultivars under greenhouse conditions.
Plants were grown in sand:perlite (1:1, v/v) medium and were irrigated every 2 days with half-strength Hoagland’s No. 2 nutrient
solutions containing different B, 0.01, 0.05, 0.10, 0.25 and 2.50 mg l−1 (0.25 and 2.50 mg l−1 were considered as control and excess B treatment, respectively, and the other three B levels were considered as low B treatments).
After treatments for 183 days, leaves (from basal, middle, upper parts of the shoots), stem of scion, stem of rootstock and
root were separately sampled. Our results showed that plant growth (plant height, root volume and dry weights of various parts)
was inhibited in response to low or excess B supplies in both cultivars. It was found that B concentrations in the upper leaves
of both cultivars were substantially higher than those in the basal leaves when low concentrations (≤0.05 mg l−1) of exogenous B were applied, suggesting that B was preferentially translocated to the upper-younger leaves to support their
growth. Analysis of B distribution in different parts indicated that translocation of B from the root to the scion’s shoots
(stems and leaves of scion) may be restricted upon exposure to low B conditions. When B was inadequately supplied, growth
of ‘Skagg’s Bonanza’ was better than ‘Newhall’, implying that the former cultivar was more tolerant to low B status, which
may be due to the higher efficiency of B translocation from the root to the scion’s shoots. However, when the plants were
treated with excess B (2.50 mg l−1), both cultivars showed a similar degree of B toxicity. The probability of scion–rootstock interactions in relation to the
differential responses of growth and different efficiency of B translocation involved in the two orange cultivars following
the long-term low B stress were discussed. 相似文献
16.
Larval mortality ofNeodiprion sertifer (Geoffroy),Diprion pini (L.) andGilpinia pallida (Klug) were studied in field experiments around a factory complex in southwestern Finland. Larval colonies were transferred
on the shoots of Scots pines growing at different distances from the emission source. Larval mortality was highest near the
factories. InN. sertifer, larval mortality caused by the nuclear polyhedrosis virus was higher and cocoon mortality caused by parasitoids was lower
near the pollutant source. The most abundant parasitoid species wereSynomelix scutulata (Hartig) andLamachus eques (Hartig). 16–67% of theN. sertifer, 0–5% of theD. pini and the 73–100% ofG. pallida cocoons contained parasitoids oviposited during the larval period of the sawflies.
相似文献
17.
J. G. Roddick G. Melchers 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,70(6):655-660
Summary Analyses of leaves and ‘tubers’ from somatic hybrids of potato and tomato (‘pomato’ with plastids of potato, ‘topato’ with
plastids of tomato) produced by fusion of protoplasts from liquid cultures of dihaploid potato and mesophyll of tomato revealed
the presence of the two major potato glycoalkaloids (α-solanine and α-chaconine) as well as the tomato glycoalkaloid (αtomatine). The total alkaloid content of leaves was greater than that of ‘tubers’ and similar to levels in the foliage of
parent plants. However, glycoalkaloids were more abundant in hybrid ‘tubers’ than in normal potato tubers by a factor of 5–15.
In hybrid foliage, approximately 98% of the alkaloid present was of potato origin whereas in ‘tubers’ the reverse was the
case, with tomatine comprising 60–70% of the total alkaloid. The similarities in alkaloid content and ratios between the pomato
and the topato lines indicate that plastomes do not influence the biosynthesis and distribution of these alkaloids. The results
indicate that major secondary metabolites may prove useful for assessing the hybrid nature of such plants. 相似文献
18.
Wen Liu Xuesen Chen Guanjun Liu Qing Liang Tianming He Jianrong Feng 《Plant Cell, Tissue and Organ Culture》2007,88(3):289-299
Embryo rescue technique was used successfully to produce interspecific hybrids by crossing peach (P. persica) as a female parent with apricot (P. armeniaca) and plum (P. salicica). In those crosses that had ‘Yuhualu’ or ‘Zhonghuashoutao’ as female parents, hybrid embryos aborted from the 7th or 8th
week after pollination mainly due to post-pollination incompatibility. An embryo rescue protocol was established to rescue
such embryos and recover hybrid plants. Modified half-strength MS medium containing 4 mg l−1 6-BA and 0.5 mg l−1 IBA produced up to 90% germination in the embryos. Modified MS medium with 1.0 mg l−1 6-BA and 1.0 mg l−1 IBA gave the highest bud induction and multiplication whereas modified MS medium containing 0.5 mg l−1 IAA and 0.2 mg l−1 NAA gave the best rooting percentage. All the hybrids obtained using this embryo rescue technique were verified using simple
sequence repeat (SSR) markers. A series of pollen treatments were carried out to partially overcome pre-pollination incompatibility,
and it was found accidentally that pollen treatment with electrostatic field not only improved pollen germination but also
increased the multiplication coefficient of embryo-induced shoots. 相似文献
19.
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
20.
Sibylle Stoeckli Karsten Mody Cesare Gessler Andrea Patocchi Mauro Jermini Silvia Dorn 《Tree Genetics & Genomes》2008,4(4):833-847
The rosy apple aphid (Dysaphis plantaginea), the leaf-curling aphid (Dysaphis cf. devecta) and the green apple aphid (Aphis pomi) are widespread pest insects that reduce growth of leaves, fruits and shoots in apple (Malus × domestica). Aphid control in apple orchards is generally achieved by insecticides, but alternative management options like growing
resistant cultivars are needed for a more sustainable integrated pest management (IPM). A linkage map available for a segregating
F1-cross of the apple cultivars ‘Fiesta’ and ‘Discovery’ was used to investigate the genetic basis of resistance to aphids.
Aphid infestation and plant growth characteristics were repeatedly assessed for the same 160 apple genotypes in three different
environments and 2 consecutive years. We identified amplified fragment length polymorphism (AFLP) markers linked to quantitative
trait loci (QTLs) for resistance to D. plantaginea (‘Fiesta’ linkage group 17, locus 57.7, marker E33M35–0269; heritability: 28.3%), and to D. cf. devecta (‘Fiesta’ linkage group 7, locus 4.5, marker E32M39–0195; heritability: 50.2%). Interactions between aphid species, differences
in climatic conditions and the spatial distribution of aphid infestation were identified as possible factors impeding the
detection of QTLs. A pedigree analysis of simple sequence repeat (SSR) marker alleles closely associated with the QTL markers
revealed the presence of the alleles in other apple cultivars with reported aphid resistance (‘Wagener’, ‘Cox’s Orange Pippin’),
highlighting the genetic basis and also the potential for gene pyramiding of aphid resistance in apple. Finally, significant
QTLs for shoot length and stem diameter were identified, while there was no relationship between aphid resistance and plant
trait QTLs.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献