Physiological recovery of freezer-stored white and Engelmann spruce seedlings planted following different thawing regimes     

Edith L. Camm  Robert D. Guy  David S. Kubien  Darren C. Goetze  Salim N. Silim  Philip J. Burton 《New Forests》1995,10(1):55-77

Logistic problems of large-scale reforestation necessitate freezer-storage of conifer seedlings. Frozen stock is typically thawed slowly at low temperatures for up to several weeks before shipping to the plantation site, but the necessity of this practice is questionable. Experiments were conducted to study effects of different thawing regimes on photosynthetic recovery, frost hardiness, water relations and growth initiation in interior spruce (white spruce (Picea glauca (Moench) Voss) and Engelmann spruce (Picea engelmannii Parry) hybrid complex). One year-old container-grown seedlings were planted after 9 days post-storage thawing at 5–15 °C or still frozen, directly from the freezer. During a 29 day observation period after planting, both groups showed changes in xylem water potential (_w), carbon fixation (A), stomatal conductance (g _s ), chlorophyll a fluorescence and xanthophyll cycle pigments. Treatment differences in fluorescence and pigments peaked within one hour after planting. All differences in _w, A, g _s , ratio of internal to external CO₂ concentration (C_i/C_a), fluorescence, pigments and root number disappeared after 5 to 8 days. Terminal bud burst occurred 2.6 days earlier in the pre-thawed seedlings. When seedlings were rapidly thawed in the dark at 21 °C they achieved maximum _w (–0.2 MPa) in 3–4 hour. When evaluated 45 min after planting, A, g _s , C_i/C_a and fluorescence values of rapidly thawed seedlings were intermediate between those for seedlings planted frozen or after 9 days slow thawing, showing that the recovery process was well underway a few hours after removal from the freezer. These results suggested that a suitable on-site operational protocol for rapid thawing might be to lay frozen bundles on the ground at ambient temperature overnight. In field trials of this method, rapidly thawed seedlings broke bud 3.3 days later than slowly thawed stock and also had greater frost hardiness at time of planting. Height, shoot and root mass did not differ after 3 months growth.  相似文献   

Some of the properties of particleboard made from paulownia   总被引：3，自引：0，他引：3  

Hulya Kalaycioglu  Ilhan Deniz  Salim Hiziroglu 《Journal of Wood Science》2005,51(4):410-414

The objective of this study was to determine some of the properties of experimental particleboard panels made from low-quality paulownia (Paulownia tomentosa). Chemical properties including holocellulose, cellulose, lignin contents, water solubility, and pH level of the wood were also analyzed. Three-layer experimental panels were manufactured with two density levels using urea–formaldehyde as a binder. Modulus of elasticity (MOE), modulus of rupture (MOR), internal bond strength (IB), screw-holding strength, thickness swelling, and surface roughness of the specimens were evaluated. Panels with densities of 0.65 g/cm³ and manufactured using a 7-min press time resulted in higher mechanical properties than those of made with densities of 0.55 g/cm³ and press times of 5 min. Based on the initial findings of this study, it appears that higher values of solubility and lignin content of the raw material contributed to better physical and mechanical properties of the experimental panels. All types of strength characteristics of the samples manufactured from underutilized low-quality paulownia wood met the minimum strength requirements of the European Standards for general uses.  相似文献   

Seed germination of Albizia procera (Roxb.) Benth. in Bangladesh: a basis for seed source variation and pre-sowing treatment effect     

Md．SalimAZAD  RajibKumarBISWAS．  Md．AbdulMATIN 《中国林学(英文版)》2012,14(2):124-130

An experiment in seed morphology and seed germination techniques of Albizia procera was carried out in the nursery of the Forestry and Wood Technology Discipline,Khulna University,Bangladesh in order to discover the source variation in seeds and pre-sowing treatment effects on seed germination.Mature seeds of A.procera were collected from healthy trees in home garden plantations from five different districts in Bangladesh and treated with four pre-sowing treatments,i.e.,control,immersion in cold water (4°C for 24 h)and immersion in hot water(80°C for 10 min and 100°C for 1 min).The average length,width and thickness of seeds were calculated as 0.502±0.485,0.420±0.060 and 0.191±0.118 cm,respectively.Germination was conducted in poly-bags with a mixture of topsoil and cow dung in a ratio of 3:1.The results revealed that pre-sowing treatments affected the rate of germination of seeds,which significantly increased the germination percentages of seeds in hot water treatments compared with those in control (60.60%)and the cold water treatment(4°C for 24 h,63.53%).The highest germination success was 82.07%in the treatment of immersion in hot water(80°C)for 10 min,followed by 79.00%in immersion in hot water(100°C)for 1 min.Germination started 4 to 6 days after seed sowing and completed in a period of 22 to 25 days in all treatments.ANOVAs showed statistically significant differences(p0.05)in seed germination starting dates,closing dates,germination percentages and rates of germination among treatments,but no significant differences in seed germination starting dates,closing dates,germination period,germination percentages and rates of germination among the seed sources.The study also revealed that the interaction between seed source variation and treatment effect significantly differed in seed germination starting dates,closing dates,germination percentages and rates of germination. The hot water(100°C for 1 min)treatment is recommended for seed germination of A.procera in rural Bangladesh.  相似文献   

Non-escaping frost tolerant QTL linked genetic loci at reproductive stage in six wheat DH populations     

Jingjuan Zhang  MD Shahidul Islam  Yun Zhao  Masood Anwar  Zaid Alhabbar  Maoyun She  Rongchang Yang  Angela Juhasz  Guixiang Tang  Jiansheng Chen  Hang Liu  Yanjie Jiang  Shengnan Zhai  Xin Hu  Junkang Rong  Yingquan Zhang  Yebo Qin  Qier Liu  Zitong Yu  Yujuan Zhang  Sadegh Balotf  Mirza Dowla  Sonia Afrin  Nandita Roy  Md Resad Mallik  Md Atik Us Saieed  Shanjida Rahman  Nigarin Sultana  Sarah Al-Sheikh Ahmed  Chris Florides  Kefei Chen  Darshan Sharma  Nathan Height  Ben Biddulph  Meiqin Lu  Jorge EMayer  Wujun Ma 《作物学报(英文版)》2022,(1):147-165

Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time.  相似文献   

Effect of induced pyrexia on the disposition kinetics of ciprofloxacin in dogs     

Faqir Muhammad  Masood Akhtar  M. Irfan Anwar  M. Javed Arshed 《Veterinary research communications》2009,33(8):971-977

Ciprofloxacin was administered intravenously @ 5 mg/kg body weight to six healthy dogs. After a washout period of two weeks, fever was induced by injecting Escherichia (E) coli endotoxin. Ciprofloxacin was administered again. Blood samples were collected at various time intervals and analyzed for ciprofloxacin with HPLC. The kinetic analysis revealed the volume of distribution in healthy vs. febrile dogs as 2.12 ± 0.32 vs. 1.79 ± 0.43 L/Kg, respectively. The elimination half life was 2.23 ± 0.78 and 2.07 ± 0.74 hours in healthy and febrile dogs, respectively. Similarly, dogs under healthy and febrile conditions showed comparable total plasma clearance of 0.66 ± 0.06 and 0.60 ± 0.07 L/Kg/h, respectively. All these and other investigated kinetic parameters were statistically non significant. This study concludes that the pharmacokinetic behavior of ciprofloxacin is similar under healthy and febrile conditions. Thus, the kinetic studies of fluoroquinolones conducted in normal/healthy animals may be used to depict the pharmacokinetic parameters in diseased animals.  相似文献   

Effect of dietary zinc proteinate supplementation on growth performance, and skin and meat quality of male and female broiler chicks     

Salim HM  Lee HR  Jo C  Lee SK  Lee BD 《British poultry science》2012,53(1):116-124

1. An experiment was conducted to evaluate the effect of dietary zinc proteinate (ZP) supplementation on growth performance and on skin and meat quality of male and female broiler chicks.

2. A total of 240 1-d-old male and 240 1-d-old female broiler chicks were randomly distributed into 24 floor pens (12 replicate pens/sex; 20 birds/pen) and were given either 0 (Control diet) or 40?mg/kg ZP (ZP 40), resulting in a 2?×?2 factorial arrangement of treatments.

3. The growth performance of male and female broiler chicks was not affected by the ZP supplementation, but the males showed significantly higher growth performance than did females.

4. ZP supplementation increased the total thickness of skin in both sexes, and males had thicker skin than females. It also increased the collagen content of skin, but not that of meat. Males had higher skin collagen contents than did females, but no sex difference was found in the meat collagen contents.

5. ZP supplementation did not affect the shear force values of skin and meat; however, males had higher shear force values of back skin than females. ZP supplementation increased the zinc contents of thigh meat and plasma in both sexes. Males had higher zinc contents in back skin than females.

6. It is concluded that dietary ZP supplementation could increase the skin quality of broiler chicks in both sexes, particularly in female broilers, without any effect on growth performance. Male broilers have better growth performance and skin quality than females.  相似文献   

Dynamics of Growth and Water Relations of Fodderbeet and Seabeet in Response to Salinity     

B. H. Niazi  J. Rozema  R. A. Broekman  M. Salim 《Journal of Agronomy and Crop Science》2000,184(2):101-110

A pot experiment was conducted under greenhouse conditions with two subspecies of beet, fodderbeet ( Beta vulgaris cv. Majoral) and seabeet ( Beta maritima ), under saline conditions. Growth and physiological parameters (dry weight, leaf area, water relations and net photosynthesis) were recorded. The two subspecies responded differently in terms of growth parameters. Plant growth was significantly reduced at 400 m m NaCl, while no significant growth reduction occurred at 200 m m NaCl. Fairly high values of relative growth rate were associated with the leaf area of the cultivars. The water content of the shoot decreased with plant age. The fodderbeet cultivar Majoral showed a significant increase in dry matter at 200 m m NaCl after 5 weeks. This growth improvement may be related to the better adaptation of the plants under saline conditions.  相似文献   

Interactive Effects of High Boron and NaCl Stresses on Subcellular Localization of Chloride and Boron in Wheat Leaves     

S. Masood  M. A. Wimmer  K. Witzel  C. Zörb  K. H. Mühling 《Journal of Agronomy and Crop Science》2012,198(3):227-235

Salinity and boron (B) toxicity often occur simultaneously and may have interactive effects on plant responses. This study aims at further investigating long‐term effects of salinity, B toxicity and their combination on wheat plants. Plants grown in hydroponics were treated with 2.5 μm H₃BO₃ (control), 75 mm NaCl, 200 μm H₃BO₃ or 75 mm NaCl + 200 μm H₃BO₃ and were analysed on a subcellular level 6 weeks after germination. Shoot fresh and dry weight (DW), water content, transpiration rate and osmolality were reduced, while Na⁺ and Cl^? concentrations increased under salinity stress. However, Cl^? was reduced in all compartments by an additional application of B toxicity. At adequate B supply, NaCl increased apoplastic and symplastic soluble B concentrations, whereas the total B content remained unchanged. At high B level, however, soluble and total B was reduced by additional salt stress. Despite this antagonistic effect of a combined salt and B toxicity stress on Cl^? and B concentrations, an additive effect was observed regarding shoot fresh weight reduction. Our results confirm an alleviating effect of the combined stresses on toxic ion concentrations, which did not prevent additive growth reductions.  相似文献   

Light and scanning electron microscopic study on the blood vascular system of the donkey placenta     

Saber A  Abd-Elnaeim M  Hembes T  Pfarrer C  Salim A  Leiser R 《Anatomia, histologia, embryologia》2008,37(2):86-94

The donkey placenta is diffuse and epitheliochorial with numerous microplacentomes consisting of a fetal microcotyledonary and a maternal microcaruncular part. The microplacentomal vasculature during the last third of pregnancy has been investigated by light microscopy in comparison to scanning electron microscopy of the materno-fetal contact surface and corrosion casts of blood vessels after plastic instillation from either the microcotyledonary or the microcaruncular side, and, for the first time in a perissodactyle, from both sides. Morphological data were semiquantitatively evaluated. The supplying parts of both, the microcotyledonary and the microcaruncular vascular system are strictly proximo-distally oriented, thus reaching the capillary systems or working parts in the shortest way possible. The straight course of the vasculature, particularly on the fetal side, suggests the occurrence of venulo-arteriolar back diffusion. The fetal capillary system consists of convolutes confronting the maternal septal capillary complexes in a countercurrent way. This materno-fetal blood flow interrelationship is highly efficient in terms of placental exchange, which is further supported (1) by dilations and increasing coiling of the fetal venular capillary limbs in particular and (2) by a decrease in the interhaemal distance from 12.5 to 7.2 microm between the two capillary systems. Besides the countercurrent blood flow interrelationship, some maternal branch arterioles reach the septal capillary system from the maternally oriented pole of the microplacentome or microcaruncle, respectively, resulting in the less efficient crosscurrent blood flow. Hence, in the donkey placenta fetal and maternal blood vessels meet in a mix of countercurrent and crosscurrent flow patterns.  相似文献   

Partitioning of Biomass, N and S in Sunflower (Helianthus Annuus L.) by Nitrogen and Sulphur Nutrition     

G. Nabi  Rahmatullah  M. Salim  M. A. Gill 《Journal of Agronomy and Crop Science》1995,174(1):27-32

Response of sunflower ( Helianthus annuus L.) to sulphur applied ca. 0, 30, 90 and 150 mg kg^-1 and nitrogen applied ca. 0, 100 and 200 mg kg^-1 soil were studied on a Typic Camborthids in greenhouse. Nitrogen and S application had a significant (P < 0.01) main and interactive effect on seed yield and dry weight of leaves and stem. Cumulative N and S contents of sunflower seeds, stem and leaves were significantly (P < 0.01) affected by N and S application. Sulphur transport and accumulation in sunflower seeds was increased with S application. There were significant (P < 0.01) correlations between seed yield and N and S content of sunflower plants. Critical S concentration (%) in 60 days old plants was 0.36 for 95 % relative yield of the maximum. Application of 90 mg S kg^-1 with 200 mg N kg^-1 resulted in the highest seed yield and maximum total S and N contents in sunflower leaves, stem and seeds. Relative increase in sunflower seeds yield at higher levels of N and S was more than that of dry weight of stem and leaves.  相似文献