Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was...Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was conducted in Forestry College of Shenyang Agricultural University from July 1999 to July 2001. The experiment included medium selection of explant induction survival, initial culture, subculture as well as rooting culture, and forming seedling with callus. The results showed that shoot segment in vitro survive rate is larger in spring than in autumn, and green dense callus could form plantlet. The best medium for initial culture was SH+0.5mg/L BA+0.05 mg/L NAA, with a propagation coefficient of 4.1 (per micro-cutting in a month), and for subculture it was B5+0.5 mg/L BA+0.05 mg/L NAA+ 10 mg/L Glu., with a propagation coefficient of 4.7. The best rooting medium was 1/2MS+0.5 mg/L NAA+10 mg/L Glu., with a rooting rate of 84.4%. These results provide reference data for reproduction of superior individuals of Robinia pseudoacacia f. decaisneana.展开更多
To explore the physiological and biochemical mechanism of the occurrence of vitrified shoots of Populus suaveolens in tissue culture, the changes in water, chlorphyll, lignin, H2O2, phenylalanine ammonialyase (PAL), m...To explore the physiological and biochemical mechanism of the occurrence of vitrified shoots of Populus suaveolens in tissue culture, the changes in water, chlorphyll, lignin, H2O2, phenylalanine ammonialyase (PAL), malonaldehyde (MDA), protective enzymatic systems, and some key enzymes involved in the ascorbate- glutathione cycle were comparatively studied in both normal and vitrified shoots of P. suaveolens. The results show that the lower activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and PAL, and the less contents of chlorphyll, lignin, ascorbate (ASA) and reduced glutathione (GSH) as well as the lower ratios of ASA / DHA and GSH / GSSG are observed in vitrified shoots than in normal ones during the whole culture period. While in comparison with normal shoots, the higher activity of superoxide dismutase (SOD) and the more concentrations of water, H2O2, MDA, dehydroascorbate (DHA) and oxidized glutathione (GSSG) are found in vitrified shoots. Statistical analysis indicates that the enhanced activity of SOD and the decreased activities of CAT and POD as well as some enzymes involved in the ascorbate-glutathione cycle might be closely correlated to the accumulation of H2O2. The less regeneration of ASA and GSH and the lower capacity of the ascorbate-glutathione cycle observed in vitrified shoots might be due to a significant decrease in APX, MDAR, DHAR and GR activities and a decline in redox status of ASA and GSH. The decreases in chlorphyll content might result in a decline in photosynthesis. The lower activities of POD and PAL could result in the decrease of lignin synthesis and cell wall ligination, which might be the key factor leading to the increase in water content. It is concluded that the deficiency of detoxification capacity caused by the lower capacity of the ascorbate-glutathione pathway and the decreased activity of protective enzymatic system might lead to the large accumulation of H2O2 and the enhancement of membrane lipid peroxidation, which might be the main cause leading to the occurrence of vitrifying shoots of P. suaveolens in tissue culture.展开更多
Twigs of 2-3-year-old Platanus occidentalis L. were used as experimental material to find the causes for the contamination and browning in the initial stages of tissue cultures. To compare the degree of browning of ex...Twigs of 2-3-year-old Platanus occidentalis L. were used as experimental material to find the causes for the contamination and browning in the initial stages of tissue cultures. To compare the degree of browning of explants picked off from different growing seasons, the experimental material was excised from trees on each of the first ten days in January, March, May and July, 2006. The results indicated that the contamination and browning rates of the material cut off in January （14.2% and 30.6%, respectively） and March were somewhat lower than those in July. The pretreatment of soaking the explants in different anti-oxidants and absorbents at the same time could diminish some side effects. The pretreatment of using 10 g·L^-1 vitamin C reduced the contamination and brown- ing rate effectively. An orthogonal experiment showed that the optimal factor and level arrangement is 0.5 mg·L^-1BA, 2.0 g·L^-1 active carbon and 1.5 g·L^-1 PVP which resulted in a browning rate of only 16.5%. In general, sampling period, physical properties and pretreatment of explants are the main factors responsible for the contamination and browning of material in the initial stages of P. occidentalis tissue cultures.展开更多
Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia （Maiden ＆ Betche） Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propaga...Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia （Maiden ＆ Betche） Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 ＋ BA 0.6mg L^-1 ＋NAA 0.1 mg L^-1＋sucrose 30g L-l, which yielded a 75.9 % initiation rate. An efficient multi- plication medium was MS ＋ BA 0.3 mg L^-1＋ NAA 0.15 mg L^-1 ＋ sucrose 30 g L^-1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 ＋ IBA 0.1-0.25 mg L^-1 ＋ sucrose 15 g L^-1, which yielded a 100 % rooting rate, 2.94-3.32 roots per individual and 1.36-1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.展开更多
The tissue cullurc of Schloss Mannheim (Rosa Chinensus , var. Florihunda ) with full and unsprouting bud of stem segments as the explants was experimented The result shows that the buds sprouted best on MS med...The tissue cullurc of Schloss Mannheim (Rosa Chinensus , var. Florihunda ) with full and unsprouting bud of stem segments as the explants was experimented The result shows that the buds sprouted best on MS medium with the addition of 6-HA 1 .0 mg/L,. and differentiation was best on MS medium with addition of 6-BA 1 .5 + NAA0.05 + ZT0.1 mg/L, or KT 1,0 + NAA0,05 + ZT0.1mg/L. The MS emdium with addition of 6-BA 0.3 + NAA 0.0 5+ ZT0.1 mg/L, or KT 0.3 + NAA0.05 +ZT0. 1 mg/L showed a good result for developing strong shoots. 1/2 MS medium with the addition ofIBA 0.1 mg/L, or IBA0.1 + NAA0.02 mg/L, had best result for rooting. The plantlets should be transplanted from test-tube to soil when they grew ' to 2.5 ~ 4.0 cm high and have 3 ~ 5 strips short roots. Ahigher survival rate was obtained under the conditions of conterolling humidity and temperature展开更多
Dormant buds of Larix gmelinii (4-30 years old) were cultured in vitro. Axillary buds grew on the explants, and 60%-65% of the explants' axillary buds, a differentiation rate of 60% was obtained on the explants co...Dormant buds of Larix gmelinii (4-30 years old) were cultured in vitro. Axillary buds grew on the explants, and 60%-65% of the explants' axillary buds, a differentiation rate of 60% was obtained on the explants collected from the 30-year-old trees. The maximum number of axillary buds was 26 in one induction per initial explant. Bud clusters were separated into individual buds and most of them elongated into shoots. A few roots grew on the shoots. The MS (Murashige and skoog) and SH (Schenk and Hildebrandt) were more efficient media than the WPM. (Woody Plant Medium). The best hormone Combinations for the axillary bud inductions were BA1+NAA0.01 and BA2+NAA0.2 (mg/L). The procedure was as follows: (1) Apical buds were explanted on the no-hormone basal agar medium and grown for 1 or 2 weeks; (2) Explants were transferred onto the bud-inducing medium and grown for 2 weeks and then (3) Cultured on the basal medium without hormones for axillary bud elongation; (4) Bud clusters were separated and cultured continuously to a minimum height of 1.5cm; (5) shoots were cut at the base and cultured on root-inducing medium; (6) plantlets were allowed to acclimatize and then transferred to the soil.展开更多
OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by ...OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by our laboratory was used to detect the localization of AM protein in rat kidney tissue by avidin-biotin complex immunohistochemistry. The expressions of AM and its receptor CRLR mRNA on cultured glomerular epithelial cells (GEC) and MsC were investigated by Northern blot assay, and the possible effect of AM secreted by GEC on MsC proliferation was observed using [3H]thymidine incorporation as an index. RESULTS: A specific monoclonal antibody against AM was succesfully developed. AM was immunohistochemically localized mainly in glomeruli (GEC and endothelial cells), some cortical proximal tubules, medullary collecting duct cells, interstitial cells, vascular smooth muscle cells and endothelial cells. Northern blot assay showed that AM mRNA was expressed only on cultured GEC, but not on MsC, however, AM receptor CRLR mRNA was only expressed on MsC. GEC conditioned medium containing AM can inhibit MsC growth and AM receptor blocker CGRP8-37 may partially decreased this inhibitory effect. CONCLUSION: AM produced by GEC inhibits the proliferation of MsC, which suggests that AM as an important regulator is involved in glomerular normal physiological functions and pathologic processes.展开更多
In this paper a general introduction is given to research advances in genetics improvement and breeding of Chinese aspen (Populus davidiana Dode) in China. This introduction includes natural distribution and collectio...In this paper a general introduction is given to research advances in genetics improvement and breeding of Chinese aspen (Populus davidiana Dode) in China. This introduction includes natural distribution and collection, conservation, gene diversity, provenance trial, crossing breeding, vegetative propagation and disease resistant etc. Based on the current situation of forest tree breeding in China, some strategic suggestions concerning the future development of Chinese aspen genetics improvement in China are presented, taking into consideration the existing domestic demands of forestry production and international trends in forest tree breeding.展开更多
Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram...Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram（4-amino-3,5,6-trichloropicolinic acid） at different concentrations of carbohydrate under the same conditions with presence or absence of luminosity.In our experiment,secondary explants were kept in MS medium containing 8.0 mg·L-1 of Picloram for the callus formation.Calluses were transferred in MS medium supplemented with sucrose,fructose and glucose（control,2%,4% and 6%）.Results show that Picloram induced the callogenesis in leaf sheath.The secondary embryogenesis was formed in yellow-globular callus.The sucrose as carbohydrate source in the absence of light was more efficient to induce rhizogenesis.Glucose was more efficiency in the presence of light.Callogenic induction and further embryogenesis evidenced the competence and determination of leaf sheath cells.展开更多
Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in t...Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak （Tectona grand＆ L.）. Higher number of shoots （6.17） per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length, number of nodes or leaves. For rooting, 2-4 cm long softwood shoots were excised and treated with either indole-3-butyric acid （IBA） or α-naphthyl acetic acid （NAA） at 0, 1000, 2000 or 3000 μmol.L^-1 each or with combinations （1000 ＋ 1000, 2000 ＋ 2000 or 3000 ＋ 3000 μmol.L^-1） and then placed in flat trays containing autoclaved sand at 25 ± 2℃ in 16 h photoperiod at 35 μmol.m^-2.s^-1. After 28 days, softwood cuttings treated with IBA ＋ NAA （3000 ＋ 3000 μmol.L^-1） had highest rooting percentage （89.3%） with 5.5 mean roots. Shoot apex and nodal explants of softwood cuttings were pretreated with 0.1% （w/v） ascorbic acid, boric acid, activated charcoal, citric acid, glutamine or polyvinylpolypyrollidone （PVP） for 24 h to remove phenolic compounds before surface disinfestation. Glutamine （G1） and PVP were equally effective resulting in 60% establishment of shoot apices on MS medium supplemented with 10 μmol.L^-1 6-benzylaminopurine （BAP） ＋ 5 μmol.L^-1 NAA. Using shoot apices, highest （42.80） number of multiple shoots with 54.33 mm shoot length were obtained on MS ＋ BAP （8.8 p.mol.L 1） ＋ IBA （2 μmol.L^-1） after 45 days. Shoots were successfully rooted and acclimatized to greenhouse conditions.展开更多
Micropropagation mostly leads to the production of innumerable true-to-type plants. However, establishing pathogen-free explants through in vitro culture requires a precise management of time for the exposure of expla...Micropropagation mostly leads to the production of innumerable true-to-type plants. However, establishing pathogen-free explants through in vitro culture requires a precise management of time for the exposure of explants to antimicrobial chemicals. The application of antimicrobial chemicals must also be managed to impose the least injury on explants. This review discusses the contributions of micropropagation procedures, explant types, subculture duration, media ingredients and plant growth regulators to the in vitro response of conifer explants. Even though regeneration from mature conifer explants such as mature shoots are laborious, the chances of variation, induced in vitro, are unlikely.展开更多
We developed a method for in vitro regenera- tion of Garcinia xanthochymus （yellow mangosteen） from matured seed segments. Multiple shoots were induced on woody plant （WP） medium supplemented with cytokinins. An a...We developed a method for in vitro regenera- tion of Garcinia xanthochymus （yellow mangosteen） from matured seed segments. Multiple shoots were induced on woody plant （WP） medium supplemented with cytokinins. An average of 11 shoots per explant were regenerated from mature seed segments on WP medium containing 20 μM 6-benzylaminopurine. Histological analysis revealed that hypodermal cells of seed segments were initially involved in active division, which later developed into meriste- moids, subsequently leading to the formation of shoot buds. Shoot elongation was achieved by repeated subculturing of seed explants in shoot regeneration medium. Rooting of shoots was achieved on WP medium supplemented with indole-3-butyric acid or s-naphthalene acetic acid. Plant- lets were transplanted to pots containing soil： compost （1：1） and survival rate was 90 %.展开更多
Robinia pseudoacacia ‘Idaho＇ is one of several multi-purpose trees used in ornamental, soil and water conservation, fodder and nectar sources. Plant abiotic stress tolerance transformed by genes could meet the requi...Robinia pseudoacacia ‘Idaho＇ is one of several multi-purpose trees used in ornamental, soil and water conservation, fodder and nectar sources. Plant abiotic stress tolerance transformed by genes could meet the requirements for reclamation of arid or alkalid lands and vegetation restoration. For this paper, we studied the effects of auxin and cytokine on Idaho locust in vitro regeneration and the establishment of gene transformation systems for plants mediated by Agrobacterium tumefaciens. Results showed that the ratios of cytokinin and auxin were the major factors affecting adventitious bud differentiation on a MS medium; the concentration of 0.5 mg·L^-16-BA benefitted callus proliferation and 0.25 mg·L^-1 IBA promoted shoot rooting; however, a higher IBA concentration will inhibit rooting. The most effective antitoxin for screening transgenic Idaho locust shoots was G418 and the most sensitive concentration of it was 8 mg·L^-1.展开更多
A protocol was discussed for high efficient plant regeneration from seven bluegrass （Poa pratensis L.） cultivars via an in- direct callus induction and somatic embryogenesis method. Mature seeds were used as explant...A protocol was discussed for high efficient plant regeneration from seven bluegrass （Poa pratensis L.） cultivars via an in- direct callus induction and somatic embryogenesis method. Mature seeds were used as explants for callus initiation. Callus induction and proliferation efficiencies were investigated on NB, modified MS （MMS） and MS media, supplemented with 2.0 mg·L^-1 2,4-dichlorophenoxyacetic acid （2,4-D）. The MMS medium performed best. Based on the MMS medium, direct and indirect callus induction effects of bluegrass from mature seeds were compared at the range of 1-5 mg·L^-1 2,4-D contained in the medium. Under the direct callus induction method, the most suitable 2,4-D concentrations varied among cultivars. Under the indirect callus induction method, a significantly high callus induction frequency （93.33%-98.33%） was obtained and there were barely any statistically sig- nificant differences among the tested genetically diverse cultivars. Somatic embryos were promoted on the MMS medium supple- mented with 3 mg·L^-1 2,4-D, 0.1 mg·L^-1 kinetin and 0.8 mg·L^-1 CuSO4. Embryogenetic calli developed into plantlets on the MMS medium containing different concentrations of thidiazuron （TDZ）, and the differentiation frequencies varied in the range from 20.15% to 77.65%. The 0.25 mg·L^-1 TDZ was generally the most suitable concentration for the tested cultivars.展开更多
文摘Robinia pseudoacacia f. decaisneana is a transfiguration of Robinia pseudoacacia. For enhancing propagation coefficient of the species, the experiment of shoot tissue culture of Robinia pseudoacacia f. decaisneana was conducted in Forestry College of Shenyang Agricultural University from July 1999 to July 2001. The experiment included medium selection of explant induction survival, initial culture, subculture as well as rooting culture, and forming seedling with callus. The results showed that shoot segment in vitro survive rate is larger in spring than in autumn, and green dense callus could form plantlet. The best medium for initial culture was SH+0.5mg/L BA+0.05 mg/L NAA, with a propagation coefficient of 4.1 (per micro-cutting in a month), and for subculture it was B5+0.5 mg/L BA+0.05 mg/L NAA+ 10 mg/L Glu., with a propagation coefficient of 4.7. The best rooting medium was 1/2MS+0.5 mg/L NAA+10 mg/L Glu., with a rooting rate of 84.4%. These results provide reference data for reproduction of superior individuals of Robinia pseudoacacia f. decaisneana.
基金Supported by National Natural Science Foundation of China (Grant No. 30271093) and the Foundation of State-designated Base for Biology Researching and Teaching in Beijing Forestry University
文摘To explore the physiological and biochemical mechanism of the occurrence of vitrified shoots of Populus suaveolens in tissue culture, the changes in water, chlorphyll, lignin, H2O2, phenylalanine ammonialyase (PAL), malonaldehyde (MDA), protective enzymatic systems, and some key enzymes involved in the ascorbate- glutathione cycle were comparatively studied in both normal and vitrified shoots of P. suaveolens. The results show that the lower activities of peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and PAL, and the less contents of chlorphyll, lignin, ascorbate (ASA) and reduced glutathione (GSH) as well as the lower ratios of ASA / DHA and GSH / GSSG are observed in vitrified shoots than in normal ones during the whole culture period. While in comparison with normal shoots, the higher activity of superoxide dismutase (SOD) and the more concentrations of water, H2O2, MDA, dehydroascorbate (DHA) and oxidized glutathione (GSSG) are found in vitrified shoots. Statistical analysis indicates that the enhanced activity of SOD and the decreased activities of CAT and POD as well as some enzymes involved in the ascorbate-glutathione cycle might be closely correlated to the accumulation of H2O2. The less regeneration of ASA and GSH and the lower capacity of the ascorbate-glutathione cycle observed in vitrified shoots might be due to a significant decrease in APX, MDAR, DHAR and GR activities and a decline in redox status of ASA and GSH. The decreases in chlorphyll content might result in a decline in photosynthesis. The lower activities of POD and PAL could result in the decrease of lignin synthesis and cell wall ligination, which might be the key factor leading to the increase in water content. It is concluded that the deficiency of detoxification capacity caused by the lower capacity of the ascorbate-glutathione pathway and the decreased activity of protective enzymatic system might lead to the large accumulation of H2O2 and the enhancement of membrane lipid peroxidation, which might be the main cause leading to the occurrence of vitrifying shoots of P. suaveolens in tissue culture.
文摘Twigs of 2-3-year-old Platanus occidentalis L. were used as experimental material to find the causes for the contamination and browning in the initial stages of tissue cultures. To compare the degree of browning of explants picked off from different growing seasons, the experimental material was excised from trees on each of the first ten days in January, March, May and July, 2006. The results indicated that the contamination and browning rates of the material cut off in January （14.2% and 30.6%, respectively） and March were somewhat lower than those in July. The pretreatment of soaking the explants in different anti-oxidants and absorbents at the same time could diminish some side effects. The pretreatment of using 10 g·L^-1 vitamin C reduced the contamination and brown- ing rate effectively. An orthogonal experiment showed that the optimal factor and level arrangement is 0.5 mg·L^-1BA, 2.0 g·L^-1 active carbon and 1.5 g·L^-1 PVP which resulted in a browning rate of only 16.5%. In general, sampling period, physical properties and pretreatment of explants are the main factors responsible for the contamination and browning of material in the initial stages of P. occidentalis tissue cultures.
文摘Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia （Maiden ＆ Betche） Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 ＋ BA 0.6mg L^-1 ＋NAA 0.1 mg L^-1＋sucrose 30g L-l, which yielded a 75.9 % initiation rate. An efficient multi- plication medium was MS ＋ BA 0.3 mg L^-1＋ NAA 0.15 mg L^-1 ＋ sucrose 30 g L^-1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 ＋ IBA 0.1-0.25 mg L^-1 ＋ sucrose 15 g L^-1, which yielded a 100 % rooting rate, 2.94-3.32 roots per individual and 1.36-1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.
文摘The tissue cullurc of Schloss Mannheim (Rosa Chinensus , var. Florihunda ) with full and unsprouting bud of stem segments as the explants was experimented The result shows that the buds sprouted best on MS medium with the addition of 6-HA 1 .0 mg/L,. and differentiation was best on MS medium with addition of 6-BA 1 .5 + NAA0.05 + ZT0.1 mg/L, or KT 1,0 + NAA0,05 + ZT0.1mg/L. The MS emdium with addition of 6-BA 0.3 + NAA 0.0 5+ ZT0.1 mg/L, or KT 0.3 + NAA0.05 +ZT0. 1 mg/L showed a good result for developing strong shoots. 1/2 MS medium with the addition ofIBA 0.1 mg/L, or IBA0.1 + NAA0.02 mg/L, had best result for rooting. The plantlets should be transplanted from test-tube to soil when they grew ' to 2.5 ~ 4.0 cm high and have 3 ~ 5 strips short roots. Ahigher survival rate was obtained under the conditions of conterolling humidity and temperature
文摘Dormant buds of Larix gmelinii (4-30 years old) were cultured in vitro. Axillary buds grew on the explants, and 60%-65% of the explants' axillary buds, a differentiation rate of 60% was obtained on the explants collected from the 30-year-old trees. The maximum number of axillary buds was 26 in one induction per initial explant. Bud clusters were separated into individual buds and most of them elongated into shoots. A few roots grew on the shoots. The MS (Murashige and skoog) and SH (Schenk and Hildebrandt) were more efficient media than the WPM. (Woody Plant Medium). The best hormone Combinations for the axillary bud inductions were BA1+NAA0.01 and BA2+NAA0.2 (mg/L). The procedure was as follows: (1) Apical buds were explanted on the no-hormone basal agar medium and grown for 1 or 2 weeks; (2) Explants were transferred onto the bud-inducing medium and grown for 2 weeks and then (3) Cultured on the basal medium without hormones for axillary bud elongation; (4) Bud clusters were separated and cultured continuously to a minimum height of 1.5cm; (5) shoots were cut at the base and cultured on root-inducing medium; (6) plantlets were allowed to acclimatize and then transferred to the soil.
文摘OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by our laboratory was used to detect the localization of AM protein in rat kidney tissue by avidin-biotin complex immunohistochemistry. The expressions of AM and its receptor CRLR mRNA on cultured glomerular epithelial cells (GEC) and MsC were investigated by Northern blot assay, and the possible effect of AM secreted by GEC on MsC proliferation was observed using [3H]thymidine incorporation as an index. RESULTS: A specific monoclonal antibody against AM was succesfully developed. AM was immunohistochemically localized mainly in glomeruli (GEC and endothelial cells), some cortical proximal tubules, medullary collecting duct cells, interstitial cells, vascular smooth muscle cells and endothelial cells. Northern blot assay showed that AM mRNA was expressed only on cultured GEC, but not on MsC, however, AM receptor CRLR mRNA was only expressed on MsC. GEC conditioned medium containing AM can inhibit MsC growth and AM receptor blocker CGRP8-37 may partially decreased this inhibitory effect. CONCLUSION: AM produced by GEC inhibits the proliferation of MsC, which suggests that AM as an important regulator is involved in glomerular normal physiological functions and pathologic processes.
文摘In this paper a general introduction is given to research advances in genetics improvement and breeding of Chinese aspen (Populus davidiana Dode) in China. This introduction includes natural distribution and collection, conservation, gene diversity, provenance trial, crossing breeding, vegetative propagation and disease resistant etc. Based on the current situation of forest tree breeding in China, some strategic suggestions concerning the future development of Chinese aspen genetics improvement in China are presented, taking into consideration the existing domestic demands of forestry production and international trends in forest tree breeding.
基金supported by FAPESP (So Paulo Research Foundation, Brazil)CAPES (Coordination for the Improvement of Higher Level, Brazil)
文摘Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram（4-amino-3,5,6-trichloropicolinic acid） at different concentrations of carbohydrate under the same conditions with presence or absence of luminosity.In our experiment,secondary explants were kept in MS medium containing 8.0 mg·L-1 of Picloram for the callus formation.Calluses were transferred in MS medium supplemented with sucrose,fructose and glucose（control,2%,4% and 6%）.Results show that Picloram induced the callogenesis in leaf sheath.The secondary embryogenesis was formed in yellow-globular callus.The sucrose as carbohydrate source in the absence of light was more efficient to induce rhizogenesis.Glucose was more efficiency in the presence of light.Callogenic induction and further embryogenesis evidenced the competence and determination of leaf sheath cells.
文摘Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak （Tectona grand＆ L.）. Higher number of shoots （6.17） per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length, number of nodes or leaves. For rooting, 2-4 cm long softwood shoots were excised and treated with either indole-3-butyric acid （IBA） or α-naphthyl acetic acid （NAA） at 0, 1000, 2000 or 3000 μmol.L^-1 each or with combinations （1000 ＋ 1000, 2000 ＋ 2000 or 3000 ＋ 3000 μmol.L^-1） and then placed in flat trays containing autoclaved sand at 25 ± 2℃ in 16 h photoperiod at 35 μmol.m^-2.s^-1. After 28 days, softwood cuttings treated with IBA ＋ NAA （3000 ＋ 3000 μmol.L^-1） had highest rooting percentage （89.3%） with 5.5 mean roots. Shoot apex and nodal explants of softwood cuttings were pretreated with 0.1% （w/v） ascorbic acid, boric acid, activated charcoal, citric acid, glutamine or polyvinylpolypyrollidone （PVP） for 24 h to remove phenolic compounds before surface disinfestation. Glutamine （G1） and PVP were equally effective resulting in 60% establishment of shoot apices on MS medium supplemented with 10 μmol.L^-1 6-benzylaminopurine （BAP） ＋ 5 μmol.L^-1 NAA. Using shoot apices, highest （42.80） number of multiple shoots with 54.33 mm shoot length were obtained on MS ＋ BAP （8.8 p.mol.L 1） ＋ IBA （2 μmol.L^-1） after 45 days. Shoots were successfully rooted and acclimatized to greenhouse conditions.
基金supported by grant from Gorgan University of Agricultural Sciences and Natural Resources(GUASNR) for multiyear project on micropropagation of Juniperus species
文摘Micropropagation mostly leads to the production of innumerable true-to-type plants. However, establishing pathogen-free explants through in vitro culture requires a precise management of time for the exposure of explants to antimicrobial chemicals. The application of antimicrobial chemicals must also be managed to impose the least injury on explants. This review discusses the contributions of micropropagation procedures, explant types, subculture duration, media ingredients and plant growth regulators to the in vitro response of conifer explants. Even though regeneration from mature conifer explants such as mature shoots are laborious, the chances of variation, induced in vitro, are unlikely.
基金supported by University Grants Commission[Project no.F.No.41-423/2012(SR)]Department of Biotechnology(DBT-KUD-IPLS programme BT/PR14555/INF/22/126/2010)+1 种基金New Delhi and Department of Atomic Energy(BRNS project no.2013/35/BRNS/20)MumbaiIndia
文摘We developed a method for in vitro regenera- tion of Garcinia xanthochymus （yellow mangosteen） from matured seed segments. Multiple shoots were induced on woody plant （WP） medium supplemented with cytokinins. An average of 11 shoots per explant were regenerated from mature seed segments on WP medium containing 20 μM 6-benzylaminopurine. Histological analysis revealed that hypodermal cells of seed segments were initially involved in active division, which later developed into meriste- moids, subsequently leading to the formation of shoot buds. Shoot elongation was achieved by repeated subculturing of seed explants in shoot regeneration medium. Rooting of shoots was achieved on WP medium supplemented with indole-3-butyric acid or s-naphthalene acetic acid. Plant- lets were transplanted to pots containing soil： compost （1：1） and survival rate was 90 %.
文摘Robinia pseudoacacia ‘Idaho＇ is one of several multi-purpose trees used in ornamental, soil and water conservation, fodder and nectar sources. Plant abiotic stress tolerance transformed by genes could meet the requirements for reclamation of arid or alkalid lands and vegetation restoration. For this paper, we studied the effects of auxin and cytokine on Idaho locust in vitro regeneration and the establishment of gene transformation systems for plants mediated by Agrobacterium tumefaciens. Results showed that the ratios of cytokinin and auxin were the major factors affecting adventitious bud differentiation on a MS medium; the concentration of 0.5 mg·L^-16-BA benefitted callus proliferation and 0.25 mg·L^-1 IBA promoted shoot rooting; however, a higher IBA concentration will inhibit rooting. The most effective antitoxin for screening transgenic Idaho locust shoots was G418 and the most sensitive concentration of it was 8 mg·L^-1.
文摘A protocol was discussed for high efficient plant regeneration from seven bluegrass （Poa pratensis L.） cultivars via an in- direct callus induction and somatic embryogenesis method. Mature seeds were used as explants for callus initiation. Callus induction and proliferation efficiencies were investigated on NB, modified MS （MMS） and MS media, supplemented with 2.0 mg·L^-1 2,4-dichlorophenoxyacetic acid （2,4-D）. The MMS medium performed best. Based on the MMS medium, direct and indirect callus induction effects of bluegrass from mature seeds were compared at the range of 1-5 mg·L^-1 2,4-D contained in the medium. Under the direct callus induction method, the most suitable 2,4-D concentrations varied among cultivars. Under the indirect callus induction method, a significantly high callus induction frequency （93.33%-98.33%） was obtained and there were barely any statistically sig- nificant differences among the tested genetically diverse cultivars. Somatic embryos were promoted on the MMS medium supple- mented with 3 mg·L^-1 2,4-D, 0.1 mg·L^-1 kinetin and 0.8 mg·L^-1 CuSO4. Embryogenetic calli developed into plantlets on the MMS medium containing different concentrations of thidiazuron （TDZ）, and the differentiation frequencies varied in the range from 20.15% to 77.65%. The 0.25 mg·L^-1 TDZ was generally the most suitable concentration for the tested cultivars.
