Propagation of Musa textilis Neé plants from apical meristem slices in vitro

Cultures were propagated from apical meristem slices of Musa textilis plants. They were cultured in vitro in light on either MS medium containing BAP (10 mg/l), but without edamin or MS mineral salts supplemented with 100 mg/l each of inositol, tyrosine, ascorbic acid; 150 mg/l citric acid; 2 mg/l cysteine; 0.4 mg/l thiamine HCl; 3% sucrose and 0.5–0.8% agar. Shoot initials were induced using media containing 5–10 mg/l BAP. Further promotion of shoot induction was achieved when BAP (1–3 mg/l) was supplemented with either NAA (1 mg/l) or adenine sulphate (80–160 mg/l). Shoot initials were multiplied on media containing 3–5 mg/l BAP, 0.1 mg/l IBA and 160–200 mg/l adenine sulphate. Plantlets generated roots on media without adenine sulphate but containing 1–1.5% sucrose and either NAA (0.1–1 mg/l) or IBA (2–10 mg/l). Plantlets were transferred into pots in the greenhouse 7 days after rooting.     

Induction ofent-kaurene biosynthesis by low temperature in dwarf peas

Germinating pea (Pisum sativum L.) seeds of two dwarf cultivars, “Progress No. 9” and “Green Arrow”, and two tall cultivars, “Alaska” and “Alderman”, were treated with low temperature (3–5°C) for 14 days and then transferred to normal growing conditions (19–21°C for 16 h/14.5–16.5°C for 8 h) for an additional 10 days. Biosynthesis of [¹⁴C]ent-kaurene from [¹⁴C]2-mevalonic acid (2-MVA) was assayed in cell-free enzyme extracts prepared from shoot tips 10 days after cold treatment and was compared with activity in enzyme extracts prepared from noncold-treated, 10-day-old control plants. Shoot lengths of cold-treated plants were measured throughout a 35-day period and compared with shoot lengths of plants grown without cold treatment for 25–35 days. Low temperature induced a five-to 10-fold enhancement ofent-kaurene, hence potentially gibberellin (GA), biosynthesis in seedlings of the two dwarf cultivars but not in the tall cultivars. However, the lack of an increase in growth rate in the cold-treated dwarfs indicated that endogenous GA biosynthesis remained blocked at some point beyondent-kaurene in the biosynthetic pathway. Since the late-flowering “Alderman” cultivar did not exhibit enhanced biosynthesis ofent-kaurene, it appears that if vernalization in late-flowering cultivars of peas is correlated with enhanced GA biosynthesis, it is not the early part of the biosynthetic pathway which is affected.     

Effect of benzylaminopurine and thidiazuron onin vitro shoot proliferation ofTilia cordata MILL.,Sorbus aucuparia L. andRobinia pseudoacacia L.

Benzylaminopurine and thidiazuron stimulated shoot proliferation ofTilia, Sorbus andRobinia. Low concentration of BAP (0.2—1.0 mg I^?1) promoted axillary bud formation and shoot elongation. Thidiazuron displayed high cytokinin activity at very low concentrations (0.002—0.05 mg I^?1). Shoot number induced on media containing thidiazuron was large. Numerous shoots were produced on the media containing BAP together with thidiazuron. Shoots produced on media containing thidiazuron or BAP together with thidiazuron rooted after transfer to medium supplemented with low concentration of auxin (IBA or NAA).     

A new procedure for increasing efficiency of protoplast plating and clone selection

Sea Prep^TM agarose (FMC corp.) was used as a gelling agent for media in the culture of potato and tomato protoplasts. The concentration and conditions appropriate for gelling and liquifaction were determined. The new method provided increased calli transfer efficiency of up to 50-fold. Shoot formation from the protoplast-derived cells occurred normally and without reduction in frequency.     

Micropropagation of Laburnum anagyroides Medic. through axillary shoot regeneration

An in vitro propagation system based on the proliferation of axillary buds has been developed for Laburnum anagyroides. Culture initiation was influenced by explanting season, with the maximum response obtained from explants harvested in spring and autumn while the lowest response was noted in summer explants. The best shoot induction was observed on Murashige and Skoog medium (MS) supplemented with 2.22 μM 6-benzylaminopurine (BAP). The basal media, type of cytokinin, and explant type were the most important factors affecting shoot multiplication of L. anagyroides. Medium comprised of ½MS salts was found to be more efficient for axillary shoot multiplication compared to full-strength MS or Wood Plant Medium (WPM) when using identical growth regulators. Shoot tip explants were more responsive than nodal segments of microshoots for micropropagation. In vitro-derived shoots, >10 mm in length, were successfully rooted in medium containing ¼MS salts and 2.68 μM α-naphtalene acetic acid (NAA). In vitro-regenerated plantlets were adapted to ex vitro conditions and transferred to a greenhouse. This is the first report for successful in vitro propagation of L. anagyroides from bud explants of mature trees.     

Effect of nitrogen sources on shoot bud differentiation ofDioscorea deltoidea Wall. callus cultures

Tuber callus by subculture ofDioscorea deltoidea Wall, was grown with different sources of nitrogen on N-free Murashige and Skoog’s basal media supplemented with a high level of kinetin (1, 3, 6, 9 and 12 ml 1^-1) and low concentration of auxin (0.01 mg 1^-1 2,4-D) for shoot bud differentiation. Shoot and root differentiation was observed only in the case of ammonium nitrate. Other sources of nitrogen failed to produce shoot bud differentiation except in the case of ammonium citrate where tissues were slight green in colour and were recognizable as pro-embryo.     

Plant growth regulation with triazoles of the dioxanyl type

The plant growth retarding activities of several dioxanylalkyl and dioxanylalkenyl triazoles were determined in seedlings of barley, rice, and oilseed rape. Out of these groups some substances proved to be among the most efficient growth retardants known. The compound 1-(4-trifluormethyl)-2-(1,2,4-triazolyl-(1))-3-(5-methyl-1,3-dioxan-5-yl)-propen-3-ol was investigated more closely. Shoot growth is reduced more intensively than root growth by this compound. At lower dosages root growth may even be stimulated. The action of this retardant can be antagonized by gibberellin A₃ and byent-kaurenoic acid. It is suggested that its main biochemical action is to block the reactions that lead froment-kaurene toent-kaurenoic acid in the course of gibberellin biosynthesis.     

Efficient plant regeneration from shoot apex explants of maize (Zea mays) and analysis of genetic fidelity of regenerated plants by ISSR markers

An efficacious regeneration system was developed from shoot apex explants of Zea mays using a two-step culture procedure. Seventeen Indian genotypes were assessed for their regeneration potential. The maximum response of shoot induction was obtained from explants cultured on Murashige and Skoog medium supplemented with 4.5 µM thidiazuron and 26.7 µM glycine. Maximum mean number of shoots (17.2) was observed in genotype COH (m)-5 while NPK was the least responsive (6.7). Shoot clumps transferred from shoot induction medium to multiplication (second) medium amended with 1.1 µM thidiazuron and 0.88 µM N ₆ -benzylaminopurine showed increased number of shoots in COH (m)-5 (36.1 shoots); NPK was the least responsive with an average of 9.5 shoots. The best response in root induction, with a larger number of roots (10.5) and longer roots (6.6 cm), was observed in Murashige and Skoog medium supplemented with 7.3 µM indole-3-butyric acid and 7.9 µM phloroglucinol. Analysis of variance indicated that plant regeneration response varied greatly among the genotypes. In vitro raised plants were successfully transferred to the field after hardening, with a 99 % survival rate. Inter simple sequence repeats analysis revealed that the similarity matrix pair-wise value was 1, the Mantel test value was p 1.0; Analysis of molecular variance genetic variances were 93 % within the population and 7 % between populations; Principal component jolliffe cut off was 0.15, Principal component and Principle coordinate analysis % variance was 13.19. These values were congruent for both the mother and the in vitro-raised plants, confirming genetic integrity.     

Effects of sediment burial disturbance on the vegetative propagation of Phalaris arundinacea with different shoot statuses

Shoot status, such as orientation and connection to the root system, and sediment burial depth after flooding disturbances have important ecological consequences on the post-flooding growth and vegetative reproduction of emergent macrophytes in wetlands. In the present study, we investigated the effect of shoot status (vertical, prostrate, or detached) and sediment burial depth (0.5 or 10 cm) on biomass accumulation and propagule production in Phalaris arundinacea (Poaceae) using an outdoor mesocosm system. In contrast to our prediction that shallow sediment burial would activate the axillary buds on prostrate shoots and regenerate more ramets, significantly fewer new ramets, rhizomes, buds, and biomass accumulation formed in P. arundinacea as the shoots changed from vertical to prostrate. Deeper sediment burial resulted in lower biomass and propagule production in plants with prostrate shoots, whereas vertical shoots increased the number of ramets. P arundinacea with detached shoots also produced a number of propagules after shallow or deep sediment burial, which might be important for the long-distance dispersal of P. arundinacea. These results suggest that P. arundinacea is a potentially invasive species in many lacustrine wetlands, particularly those with a high sedimentation rate, due to its high capacity for vegetative propagation.     

Photoperiod and plant growth regulator combinations influence growth and physiological responses in Pelargonium sidoides DC.

The aim of the present study was to evaluate the influence of photoperiod and meta-methoxytopolin riboside (MemTR)-auxin combinations on in vitro growth and physiological responses of Pelargonium sidoides DC. Shoot proliferation was highest under the conventional 16-h photoperiod. Based on the superiority of MemTR among other cytokinins from our previous study, it was selected for evaluating the cytokinin-auxin combination effect under long-day conditions. MemTR-auxin combinations had a significant effect on shoot proliferation compared to the control. The highest shoot proliferation rate (4.5 shoots/explant) was obtained on Murashige and Skoog medium supplemented with a combination of MemTR (1.0 μM) and α-naphthaleneacetic acid (NAA; 0.5 μM). Furthermore, combinations of MemTR and auxins had a synergistic effect on the concentration of photosynthetic pigments. On the other hand, photoperiod had no significant effect on the concentration of photosynthetic pigments. Formation of leaf glandular trichomes was influenced by photoperiod. Both 12- and 16-h photoperiods led to higher glandular trichome densities on the abaxial leaf surfaces of P. sidoides compared to plants grown under the 24-h photoperiod. MemTR-auxin combinations had a significant effect on the concentration of total phenolic compounds and flavonoids.     

Study of liquid culture system for micropropagation of the medicinal plant Solanum nigrum L. and its effect on antioxidant property

Solanum nigrum Linn., known for hepatoprotective and antioxidant properties, is extensively harvested from the wild. Supply is far short of demand, necessitating requirement of efficient in vitro propagation protocols. Nodal explants from wild S. nigrum plants were cultured in vitro in MS medium supplemented with 3.0 mg L^?1 IAA, 0.5 mg L^?1 BAP and gelled with 0.8 % agar. After 30 days, shoots buds were transferred to liquid MS medium of same composition. Subsequent subculture was carried out every 6 days. Shoot doubling time in solid and liquid media was calculated. Total phenolics, proanthocyanidin and flavonoid contents, ABTS^.+ and hydrogen peroxide radical scavenging antioxidant capacity of wild and in vitro aqueous leaf extracts were estimated and compared. In MS agar, 18 shoot buds were produced per explant after 30 days of culture, with shoot doubling time of 7.11 days. In liquid media, 21 shoots per explant were produced in 6 days, with a 5-fold higher multiplication rate and shoot doubling time of 1.37 days. Leaves were morphologically similar to those of wild plants. Total phenolics, proanthocyanidin and flavonoid contents of in vitro leaf extracts was 5–10 times higher than that of wild plants while ABTS^.+ and H₂O₂ radical scavenging activity was similar in both extracts. Liquid media is better suited for in vitro propagation of S. nigrum since enhanced multiplication rate was observed with shorter subculture intervals. Moreover, plants retained normal morphology and antioxidant property.     

Effects of temperature on the development and growth of winter wheat roots

Wheat plants were grown in columns of soil until early stem elongation at a wide range of constant root temperatures. Two light environments were imposed and three levels of nitrogen fertilizer added at sowing. Shoot and root development and growth were measured by destructive sampling to investigate the combined effects of temperature and changing nutrient and assimilate supply. Both mainstem leaf and root axis production were linearly related to thermal time above a base temperature of 0°C. Low irradiance affected the appearance of mainstem tillers and associated nodal root axes. Nitrogen had little effect on shoot or root development but increased shoot area between 6 and 8 mainstem leaves. Higher temperatures and supplementary light resulted in larger root systems when compared at equivalent times after sowing. Total root length and root dry weight increased exponentially with thermal time, based on the mean of 4 cm soil and 2 cm air temperatures, but no single relation existed for all temperature and light treatments. Total plant dry matter, root length and root dry weight increased linearly with accumulated, intercepted, photosynthetically active radiation. Root growth responded less than the shoot to supplementary light. Increasing temperature reduced the proportion of root weight to total plant weight.     

High-Frequency Regeneration by Abscisic Acid (ABA) from Petiole Callus of Jatropha curcas

Jatropha curcas L. is attaining worldwide interest as an important biofuel crop. Experiments were conducted to improve the prevailing micropropagation technique as well as to develop a new ex vitro rooting method for J. curcas plant regeneration. Regeneration and ex vitro rooting efficiency was enhanced by augmenting the culture medium with abscisic acid (ABA). Different concentrations of 6-benzylaminopurine (BAP) and indole-3-butyric acid (IBA) were tested for callus generation from both in vitro and in vivo explants (leaf and petiole) on Murashige and Skoog (MS) medium. The best regenerative callus was achieved on MS medium supplemented with BAP (4.44 μM) and IBA (2.45 μM) from in vitro-cultured petioles. Highest regeneration (91%) was achieved by culturing petiole callus on MS medium supplemented with BAP (8.88 μM), IBA (0.49 μM), and ABA (1.9 μM), whereas 61% regeneration was obtained from in vitro leaf callus. Shoot proliferation and elongation was achieved on BAP (2.22 μM) and IAA (8.56 μM) with 10–13 shoots per explants. Highest rooting (65%) was achieved from M1 shoots (BAP, IAA, and ABA) on MS medium supplemented with IBA (2.45 μM), naphthaleneacetic acid NAA (0.54 μM), and 0.02% activated charcoal. Ex vitro rooting of 1-mo-old M1 shoots obtained from the charcoal-containing medium resulted optimum rooting (>72%) when transferred to polybags containing sterile sand. The plantlets were successfully acclimatized in soil with more than 98% survival rate in the greenhouse.     

Productivity and root/shoot ratio of reedswamp species growing in outdoor hydroponic cultures

The study of the annual productivity of some reedswamp species grown in hydroponic sand cultures is described. The plants were cultivated in the open in a mixture of diatomite earth and sand, and irrigated periodically with a nutrient solution. The cultivation tanks were arranged in tiers to enable a continuous passage of the nutrient solution through the rooting medium. The plants were grown from small rhizome cuttings or seedlings one year old. Harvests at intervals of 1 to 3 years made it possible to follow and assess in quantitative terms the dry matter production of both aerial (shoots) and underground organs (“Root/Shoot” Ratio) and the annual dry weight increase of the underground biomass of these perennial species. The research included macro- and microclimatological measurements of temperature (air, substrate), humidity and incident (global) solar radiation. The annual productivity and the efficiency of incident solar energy utilization in the yields of cultivated reedswamp species are compared with corresponding values of the same species in natural stands. The values of production (standing crop), net annual productivityC, and the coefficient of solar energy conversion η were very high, surpassing in several cases those of natural habitats. The significance of these findings is discussed.     

Abscisic acid promotes shoot regeneration in Arabidopsis zygotic embryo explants

An efficient shoot organogenesis protocol for Arabidopsis zygotic embryo explants of Landsberg erecta ecotype was established. This de novo shoot organogenesis protocol has three different steps, i.e., induction of callus in an auxin-rich callus induction medium, the formation of green-organogenic callus in the shoot induction medium (SIM), and the final morphological differentiation of shoot in the hormone-free shoot development medium (SDM). Abscisic acid (ABA), auxin, and cytokinin (CK) were used in the SIM. Individual plant growth regulators as well as their combination were studied to understand their importance in the shoot induction treatment. We found that a combination of ABA + CK and ABA + CK + auxin induced higher shoot organogenic ability in the callus than ABA, CK, and auxin alone. Optimum ABA concentration on shoot organogenesis was determined to be 10^?5 M. Morphological characterization of callus induction and shoot organogenesis events indicated that calli were derived from the cotyledons of zygotic embryo explants and the formation of green organogenic calli was specific to the exogenous inclusion of ABA + CK in the SIM. During the time of shoot development, the green organogenic callus became darker green due to the formation of anthocyanins. Shoot organogenic calli in the SIM and the SDM were easily identified by the green-colored calli and anthocyanin pigments, respectively. Furthermore, we demonstrated the significance of exogenous and endogenous ABA in shoot organogenesis by fluridone treatments. The inclusion of ABA in SIM has a significant effect on shoot formation.     

Droplet-vitrification cryopreservation of <Emphasis Type="Italic">in vitro</Emphasis>-grown shoot tips of grapevine (<Emphasis Type="Italic">Vitis</Emphasis> spp.)

An efficient and broad-spectrum protocol for cryopreservation of Vitis spp. shoot tips by droplet-vitrification is reported. Shoot tips (1.0 mm) containing 5–6 leaf primordia (LPs) were precultured for 3 d with a preculture medium containing 0.3 M sucrose, 0.16 μM glutathione, and 0.14 μM ascorbic acid. Precultured shoot tips were treated for 20 min at 24°C with a loading solution composed of 2 M glycerol and 0.4 M sucrose, followed by exposure at 0°C to half-strength plant vitrification solution 2 (PVS2) for 30 min, and then full-strength PVS2 for 50 min. Dehydrated shoot tips were transferred into 2.5-μL PVS2 carried on aluminum foil, prior to a direct immersion in liquid nitrogen. With this method, an average shoot regrowth level of 50.5% was obtained from cryopreserved shoot tips in six V. vinifera genotypes (three wine cultivars, two table cultivars, and one rootstock) and two V. pseudoreticulata genotypes. Vegetative growth of the regenerants recovered from cryopreservation, significantly increased as the number of subculture cycles increased and was greater than the control after the third subculture following cryopreservation. Inter-simple sequence repeats (ISSR) and random amplification of polymorphic DNA (RAPD) analyses did not detect any polymorphic loci in the plants of V. vinifera L. cv. ‘Cabernet Sauvignon’ from cryopreserved shoot tips compared to the original cultures. This droplet-vitrification cryopreservation method provides a technical platform to set up cryobanks of Vitis spp.     

Detection and validation of novel QTL for shoot and root traits in barley (Hordeum vulgare L.)

Shoot and root attributes are essential for plant performance in agriculture. Here, we report detection and validation of quantitative trait loci (QTL) for shoot and root traits in 301 BC₂DH lines achieved by crossing cultivar Scarlett and wild barley accession ISR42-8. Phenotypic evaluations were made for six traits across 3 years under control and drought conditions. QTL analysis was performed using 371 DNA markers genotyped by different protocols, such as sequence repeats, diversity array technology as well as gene-specific markers. Marker by trait analysis revealed 33 QTL of which 15 and 18 QTL showed trait-improving effects of the exotic and elite alleles, respectively. Two major QTL for plant height (PH) were found on chromosome 2H (QPh.S42.2H) and 3H (QPh.S42.3H.b). The strongest QTL QSdw.S42.5H for increasing shoot dry weight was associated with an exotic allele on chromosome 5H. QTL QTkw.S42.1H underlie a novel exotic allele that improved thousand kernel weight. Seven QTL were associated with root dry weight of which at four loci introgression of exotic alleles enhanced traits values. The strongest QTL QRdw.S42.7H was linked to a gene-specific marker VrnH3 on chromosome 7H. At QRl.S42.5H, the exotic allele accounted for a 9 % increase in root length. In addition, 18 epistatic interactions were linked to PH, shoot and root dry weights. QTL validation was performed with 53 introgression lines (ILs) carrying ISR42-8 introgressions in the Scarlett background. Nine novel QTL alleles of exotic origin were validated in the isogenic background. These QTL-bearing ILs provide valuable genetic resources for plant breeding and positional cloning of the underlying genes.     

Inheritance and QTL mapping of related root traits in soybean at the seedling stage

Key message

This study provides a foundation for further research on root genetic regulation and molecular breeding with emphasis on correlations among root traits to ensure robust root growth and well-developed root systems.

Abstract

A set of 447 recombinant inbred lines (RILs) derived from a cross between Jingdou23 (cultivar, female parent) and ZDD2315 (semi-wild, male parent) were used to analyze inheritance and detect QTLs related to root traits at the seedling stage using major gene plus polygene mixed inheritance analysis and composite interval mapping. The results showed that maximum root length (MRL) was controlled by three equivalent major genes, lateral root number (LRN) was controlled by two overlapping major genes, root weight (RW) and volume (RV) were controlled by four equivalent major genes. Hypocotyl length (HL) was controlled by four additive main genes, and hypocotyl weight (HW) was controlled by four additive and additive × additive epistatic, major genes; however, polygene effects were not detected in these traits. Shoot weight (SW) was controlled by multi-gene effects, but major gene effects were not detected. Twenty-four QTLs for MRL, LRN, RW, RV, SW, HL, HW were mapped on LG A1 (chromosome 5), LG A2 (chromosome 8), LG B1 (chromosome 11), LG B2 (chromosome 14), LG C2 (chromosome 6), LG D1b (chromosome 2), LG F_1 (chromosome 13), LG G (chromosome 18), LG H_1 (chromosome 12), LG H_2 (chromosome 12), LG I (chromosome 20), LG K_2 (chromosome 9), LG L (chromosome 19), LG M (chromosome 7), LG N (chromosome 3), LG O (chromosome 10), separately. Root traits were shown to have complex genetic mechanisms at the seedling stage, SW was controlled by multi-gene effects, and the other six traits were controlled by major gene effects. It is concluded that correlations among root traits must be considered to improve the development of beneficial root traits.     

Physiological performance of the cold-water coral Dendrophyllia cornigera reveals its preference for temperate environments

Cold-water corals (CWCs) are key ecosystem engineers in deep-sea benthic communities around the world. Their distribution patterns are related to several abiotic and biotic factors, of which seawater temperature is arguably one of the most important due to its role in coral physiological processes. The CWC Dendrophyllia cornigera has the particular ability to thrive in several locations in which temperatures range from 11 to 17 °C, but to be apparently absent from most CWC reefs at temperatures constantly below 11 °C. This study thus aimed to assess the thermal tolerance of this CWC species, collected in the Mediterranean Sea at 12 °C, and grown at the three relevant temperatures of 8, 12, and 16 °C. This species displayed thermal tolerance to the large range of seawater temperatures investigated, but growth, calcification, respiration, and total organic carbon (TOC) fluxes severely decreased at 8 °C compared to the in situ temperature of 12 °C. Conversely, no significant differences in calcification, respiration, and TOC fluxes were observed between corals maintained at 12 and 16 °C, suggesting that the fitness of this CWC is higher in temperate rather than cold environments. The capacity to maintain physiological functions between 12 and 16 °C allows D. cornigera to be the most abundant CWC species in deep-sea ecosystems where temperatures are too warm for other CWC species (e.g., Canary Islands). This study also shows that not all CWC species occurring in the Mediterranean Sea (at deep-water temperatures of 12–14 °C) are currently living at their upper thermal tolerance limit.     

Effects of Mild and Moderate Hypothemia Therapy on Expression of Cerebral Neuron Apoptosis Related Proteins and Glial Fiber Acidic Protein After Rat Cardio-pulmonary Resuscitation

To explore the effects of different degrees of hypothermia on brain tissue apoptosis after cardio-pulmonary resuscitation (CPR). Cardiac arrest for 5 min induced by asphyxia method was used to create CPR model. 30 SD rats were randomly divided into control group (normothermia), 33 °C hypothermia group and 30 °C hypothermia group with ten rats in each. Rats in control group received routine treatment at 25 °C room temperature after CPR; Rats in mild hypothermia and moderate hypothermia groups were given hypothermia treatment 0.5 h after CPR. Brain tissue in all groups was taken 24 h after CPR, and immunohistochemistry was used to detect the caspase-3 in cerebral cortex and glial fiber acidic protein (GFAP) expression in astrocyte. Western blotting was used to detect Bcl-2 and Bax protein expression, and histopathological change was observed in brain tissue. Compare to the control group, caspase-3 expression in cerebral neurons in hypothermia group was significantly decreased (p<0.01), which was significantly lower in 30 °C group than that in 33 °C group (p > 0.05); GFAP level in hypothermia groups was significantly increased (p < 0.01), which was higher in 30 °C hypothermia group than that in 33 °C hypothermia group (p < 0.05); Bcl-2 expression level in hypothermia group was significantly increased (p < 0.01), which was higher in 30 °C hypothermia group than that in 33 °C hypothermia group (p < 0.05); The level of Bax had no significant difference among the three groups. Hypothermia-regulated GFAP expression by decreasing caspase-3 expression and increasing Bcl-2 expression to promote brain cell signaling transduction, and further inhibited cell apoptosis and reduced brain injury. Moderate hypothermia therapy is more effective than mild hypothermia in preventing brain injure.