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Common fig (Ficus carica L.), an economically-important fruit species widely cultivated in the Mediterranean Basin, is gaining increasing interest in the tropical and subtropical regions. A vast genetic diversity of common fig is available; however, systematic studies of cultivar performance in a particular new environment are scarce. The objective of this study was to evaluate the performance of 17 common fig cultivars grown under the Malaysian tropical climate. Evaluation was based on 15 parameters relevant to fruit yield, fruit quality and pest susceptibility. The results showed variable performance among the cultivars tested; 10 cultivars performed well for orchard establishment. Cultivar ‘A134’ produced the highest fruit yield per plant (3410 g) compared to the average yield of the cultivars studied (2500 g). Cultivars ‘Fen Chan Huang’ and ‘Wuhan’ produced the highest number of fruits per plant, 119 and 82 fruits, respectively. Mealybug infestation and ostiole-end splitting are major limitations to fig cultivation in Malaysia. Cultivar ‘Longue d’Aout’ was the most susceptible to mealybug infestation; whereas cultivar ‘B110’ was the most resistant. Above 60% of the fruits of cvs. ‘Brunswick’ and ‘Qing Pi’ had split ostiole; however, this was less than 20% in cvs. ‘Longue d’Aout’ and ‘Alma’. This study facilitates successful farming of figs in Malaysia and provides insights for future development programs.

A common modern cultivation practice is bagging the fruit bunch if date palm (Phoenix dactylifera L.) which may influence fruit maturity and nutraceutical quality. Exposure of fruits to photooxidative stress induces changes in the endogenous concentrations of plant hormones and other metabolites, which may cause accelerated fruit maturity. This study was conducted to examine the effect of exposure to direct and indirect sunlight on date palm fruit development. The indirect sunlight treatment was simulated by fruit bunch bagging, a common practice in modern date production. The exposure of date palm fruits to direct sunlight-induced photooxidative stress causing an increased concentration of ascorbic acid and decreased content of chlorophyll, anthocyanins, carotenoids, and phenols compared to the fruit bagging treatment. Direct sunlight also reduced the concentration of phytohormones, including indoleacetic acid, gibberellin, and zeatin, but increased abscisic acid accumulation. The directly-exposed fruits reached a partially-mature stage (Rutab) in August, whereas the bagged fruits remained at the immature stage (Khalal). This study is the first to describe the biochemical basis of the observed improvement of date palm fruit development in response to reduced light intensity. Besides, it provides insights into controlling date palm fruit maturity and subsequently prolonging the shelf life dates on the tree; thus, extending the marketing period for the benefit of the farmers.

Nanotechnology has involved enormous attention in enhancing electromagnetic interference (EMI) shielding. The nanocomposite {Co0.5Zn0.5Fe2O4/PANI-PTSA} was synthesized in different ratios (9:1, 3:1, 1:1 and 1:3) and coded as (CZFP1, CZFP2, CZFP3 and CZFP4), respectively. X-ray diffraction, Hall effect, vibrating-sample magnetometer and then vector network analyzer in X-band were used to be characterized. The Nicholson–Ross–Weir (NRW) method was applied to determine the real and imaginary parts of the complex relative permittivity (e*) and permeability (μ*). The nanocomposite CZFP3 exhibited the best absorption property with the optimal matching thickness of 3 mm in the frequency of 8–12 GHz. The value of the maximum RL was − 2.3 dB (> 40% power absorption) at 8.1 GHz, − 17.08 dB (98% power absorption) at 9 GHz and − 24.86 dB (99.73% power absorption) at 10.9 GHz. The excellent absorption properties of Co0.5Zn0.5Fe2O4/PANI-PTSA nanocomposites with ratio weight 1:1 indicated their great potential as microwave absorbing materials.

A rapid economically viable micropropagation protocol has been developed in the present work for Morus indica L. (K-2 cultivar) utilizing the readily available nodal explants. Explants were established on different plant growth regulators (PGRs) either individually or in combinations. MS medium containing 1 mg L−1 Kinetin (Kin) showed the best shoot multiplication with 4.8 ± 0.23 cm average shoot length and 6.5 ± 0.03 number of internodes. Regenerated shoots were elongated in MS medium supplemented with 1.5 mg L−1 gibberellic acid (GA3). Elongated shoots cultured in full-strength MS medium supplemented with 1 mg L−1 2,4-dichlorophenoxyacetic acid (2,4-D) for one week and then cultured in half-strength MS proved to be more effective in rooting compared to other PGRs in significantly shorter duration. Micropropagated plants transferred to soil fortified with the quarter-strength of MS salts along with humidity regulation process showed 89% survival frequency. In vitro flowering in the regenerated shoots was also observed in the MS medium supplemented with (1.5 mg L−1) Kin and carbon source replaced by commercial sugar cubes. This method can be effectively used for in vitro culture of M. indica in commercial scale owing to its enhanced quality and reduced time frame.

Improvement of microwave-absorbing materials (MAMs) is the most important research area in various applications, such as in communication, radiation medical exposure, electronic warfare, air defense, and different civilian applications. Conducting polymer, polyaniline doped with para toluene sulphonic acid (PANI-PTSA) as well as cobalt ferrite (CoFe2O4) is synthesized by sol–gel method and intensely blends in different ratios. The characterization of the composite materials, CoFe2O4/PANI-PTSA (CFP1, CFP2, CFP3 and CFP4), was performed by X-ray diffraction (XRD), atomic force microscopy (AFM) and vibrating sample magnetometry (VSM). The microwave-absorbing properties’ reflection loss (dB) and important parameters, such as complex relative permittivity (e r ′–je r ″) and complex relative permeability (µ r ′–jµ r ″) were measured in different microwave frequencies in the X-band (8.2–12.4 GHz) region. The composite material CFP3 showed a wider absorption frequency range and maximum reflection loss of − 28.4 dB (99.8% power absorption) at 8.1 GHz and − 9.6 dB (> 90% power absorption) at 11.2 GHz, and so the composite can be used as a microwave absorber; however, it can be more suitable for application in daily life for making cell phones above 9 GHz. Also the results showed that the thicker composites like CFP3 (4 mm) exhibit obviously better EMI SE as compared with the thinner ones (0.19, 0.19, 0.3 mm); this may be related to the low transmission of the EM wave from the composites.

Microvesicles (or MVs) are plasma membrane-derived vesicles released from most eukaryotic cells constitutively during early apoptosis or at higher levels after chemical or physical stress conditions. This review looks at some of the functions of MVs in terms of intercellular communication and ensuant signal transduction, including the transport of proteins (unconventional protein export) as well as of mRNA and microRNA. MVs also have roles in membrane repair, the removal of misfolded proteins, and in the control of apoptosis. We also discuss the role MVs have been shown to have in invasive growth and metastasis as well as in hypoxia in tumours and cerebral ischaemia. The association of MVs in infectious and autoimmune disease is also summarised together with their possible use as therapeutic agents.

Horizontal gene transfer (HGT), in relation to genetic transfer between hosts and parasites, is a little described mechanism. Since the complement inhibitor CRIT was first discovered in the human Schistosoma parasite (the causative agent of Bilharzia) and in Trypanosoma cruzi (a parasite causing Chagas' disease), it has been found to be distributed amongst various species, ranging from the early teleost cod to rats and humans. In terms of evolutionary distance, as measured in a phylogenetic analysis of these CRIT genes at nucleotide level, the parasitic species are as removed from their human host as is the rat sequence, suggesting HGT. The hypotheses that CRIT in humans and schistosomes is orthologous and that the presence of CRIT in schistosomes occurs as a result of host-to-parasite HGT are presented in the light of empirical data and the growing body of data on mobile genetic elements in human and schistosome genomes. In summary, these data indicate phylogenetic proximity between Schistosoma and human CRIT, identity of function, high nucleotide/amino acid identity and secondary protein structure, as well as identical genomic organization.

This study was conducted to develop a micropropagation protocol for grey mangrove, Avicennia marina (Forsk.)

Growth and physiological responses of date palm. Phoenix dactylifera L. cv. Barhee, callus to salinity stress were examined. Callus induced from shoot tips of offshoots was cultured on Murashige and Skoog medium supplemented with NaCl at concentrations ranging from 0 to 225 mM, in consective increments of 25 mM. Data obtained after 6 wk of exposure to salt have shown a significant increase in callus proliferation in response to 25 mM NaCl the lowest level tested, beyond which callus weight decreased. At 125 mM NaCl and higher, callus growth was nearly completely inhibited. Physiological studies on callus exposed to salt stress have shown an increase in proline accumulation in response to increased salinity. Proline accumulation was correlated to callus growth inhibition. Furthermore, increasing the concentration of NaCl in the culture medium generally resulted in a steady increase in Na+ and reduction in K+ concentrations. However, at 25 mM NaCl, the only level at which callus growth was significantly enhanced, an increase in K+ content was noted, in comparison to the NaCl free control. In response to increasing external NaCl level, the Na+/K+ ratio increased The Na+/K+ ratio was positively correlated to proline accumulation and hence callus growth inhibition. This study provides, an understanding of the response of date palm callus to salinity, which is important for future studies aimed at developing strategies for selecting and characterizing somaclonal variants tolerant to salt stress.

This study was conducted to examine the effect of biotin and thiamine concentrations on callus growth and somatic embryogenesis of date palm (Phoenix dactylifera L.). Embryogenic callus derived from offshoot tip explants was cultured on hormone-free MS medium containing biotin at 0, 0.1, 1, or 2 mg l−1 combined with thiamine at 0.1, 0.5, 2, or 5 mg l−1. Embryogenic callus weight, number of resultant embryos, and embryo length were significantly influenced by thiamine and biotin concentration. The optimum callus growth treatment consisted of 0.5 mg l−1 thiamine and 2 mg l−1 biotin. This treatment also gave the highest number of embryos. Embryo elongation was greatest at 0.5 or 2 mg l−1 thiamine combined with 1 mg l−1 biotin. Embryos from all treatments germinated and regenerants exhibited normal growth in soil. This study provides an insight into the importance of optimizing various culture medium components to overcome in vitro recalcitrace of date palm.

Ethylene is a plant growth regulator that is known to influence in vitro morphogenesis. This study investigated the effects of three ethylene inhibitors, silver nitrate (AgNO3), 2,5-norbornadiene, and cobalt chloride (CoCl2), on the regeneration of cowpea from cotyledon explants. Significant increases in the percentage of regeneration occurred as a result of adding either 50 µM AgNO3 or 100 µM 2,5-norbornadiene. The number of shoots produced per explant was enhanced by adding 25 µM CoCl2 or 100 µM norbornadiene. Maximum shoot elongation was obtained with 25 µM of either CoCl2 or norbornadiene. The effect of the duration of exposure to AgNO3 was also determined. The greatest percent regeneration was obtained with the addition of 60 µM AgNO3 either to both the initiation and regeneration stages, or to only the regeneration stage. The promotive effects on organogenesis in response to ethylene inhibitors suggests an important role for ethylene in the process of in vitro morphogenesis of cowpea and may contribute to its normally low regeneration frequency.

A system for micropropagation of Epimedium grandiflorum Morr. from rachis explants was developed. Explants were cultured onto Murashige and Skoog (MS) basal salts medium supplemented with (per L) 100 mg myo-inositol, 2 mg pyridoxine-HCl, 2 mg nicotinic acid, 0.40 mg thiamine-HCl, 30 g sucrose, and 2 g Phytagel. The medium also contained 2,4-dichlorophenoxyacetic acid (2,4-D) at 0.1, 0.2, or 0.25 mg/L (0.5, 0.9, or 1.1 µM) combined with either N6-benzyladenine (BA) or 2-isopentenyl adenine (2ip) at 2.5, 5, or 10 mg/L (11.1, 22.2, or 44.4 µM BA or 12.3, 24.6, or 49.2 µM 2iP). Cultures were maintained at a 16-h photoperiod (40 µmol/m2/s) and 23±2° C. Callogenesis preceded shoot regeneration. Callus formation increased with higher 2,4-D concentrations. The highest percent regeneration, 83% of explants, was obtained on 10 mg BA per L (44.4 µM) combined with 0.25 mg 2,4-D per L (1.1 µM). The maximum number of shoots, 15 per explant, was obtained from explants cultured on a medium containing 0.1 mg 2,4-D per L (0.45 µM) combined with 2.5 mg BA per L (11.1 µM). Maximum shoot length, 0.4 cm, was obtained on 5 mg BA per L (22.2 µM) combined with 0.2 mg 2,4-D per L (0.9 µM). To produce whole plants, shoots were separated and rooted on hormone-free medium containing 1 g activated charcoal per L. Rachises provided an excellent source of explants for Epimedium micropropagation and proved suitable for callus production.

Transgenic spinach (Spinacia oleracea L.) plants expressing cucumber mosaic virus (CMV) coat protein genes were regenerated. Leaf and hypocotyl explants from two spinach cultivars, ‘Fall Green’ and ‘High Pack,’ were transformed with Agrobacterium tumefaciens strain LBA 4404 carrying the binary vector pBI121 in which the β-glucuronidase (GUS) gene was replaced with the coat protein gene of CMV isolate SP103 or SP104. Calluses were induced from both cultivars at rates of 10-27% on MS selective medium containing 86 µM kanamycin, 237 µM carbenicillin and 209 µM cefotaxime. After 12 wk (three transfers), putatively transformed calluses were transferred to MS medium without kanamycin to promote callus proliferation. Shoots were regenerated at the rates of 23-29% for ‘High Pack’ and less than 0.5% for ‘Fall Green’. Approximately 80% of the regenerated shoots from both cultivars were subsequently induced to establish whole plants. Regenerated plants were screened for transgene incorporation using a polymerase chain reaction (PCR) method using the same primer pair originally used to amplify the CMV coat protein genes for insertion into pBI121. Based on the PCR screening, approximately 12% of the regenerated spinach plants contained a CMV coat protein gene. Southern blot analysis confirmed the presence of viral coat protein genes in the plant genomes. Western blot analysis indicated that the CMV coat protein genes were expressed in transgenic spinach plants.

Shoot multiplication was induced in cowpea, cv. Georgia-21, from shoot tip explants. Shoot tips, 5 mm long, were isolated from in vitro-grown seedlings and cultured on MS medium containing N6-benzyladenine (BA) at 1, 2.5, or 5 mg/liter (4.4, 11.1, or 22.2 µM) or 6-furfurylaminopurine (kinetin) at 1, 2.5, or 5 mg/liter (4.6, 11.6, or 23.2 µM) combined with 2,4-dichlorophenoxyacetic acid (2,4-D) at 0.01, 0.1, or 0.5 mg/liter (0.05, 0.5, or 2.3 µM) or naphthaleneacetic acid (NAA) at 0.01, 0.1, or 0.5 mg/liter (0.05, 0.5, or 2.7 µM). Cultures were maintained at a 12-h photoperiod (40 µmol·m−2·s−1) and 23 ± 2° C. Treatments with BA induced greater shoot proliferation than those with kinetin. The highest number of shoots was produced on 5 mg (22.2 µM) BA per liter in combination with NAA or 2,4-D at 0.01 mg/liter (0.05 µM). Callus proliferated from the basal ends of shoot pieces in all treatments. The cultures also formed roots in the presence of kinetin, but not on BA-containing medium. To produce whole plants, the shoots were separated and rooted on 0.1 mg (0.5 µM) NAA per liter. Resulting plants grew normally under greenhouse conditions. Shoot tips provide an excellent explant source for cowpea micropropagation and can be used for callus induction.

This study was conducted to establish and optimize a regeneration system for adapted U.S. rice genotypes including three commercial rice cultivars (LaGrue, Katy, and Alan) and two Arkansas breeding lines. Factors evaluated in the study were genotype, sugar type, and phytohormone concentration. The system consisted of two phases, callus induction and plant regeneration. In the callus induction phase, mature caryopses were cultured on MS medium containing either 1% sucrose combined with 3% sorbitol or 4% sucrose alone, and 0.5 to 4 mg·L−1 (2.26 to 18.10 μM) 2,4-D with or without 0.5mg·L−1) (2.32 μM) kinetin. In the plant regeneration phase, callus was transferred to 2,4-D-free MS medium containing 0 or 2 mg·L−1 (9.29 μM) kinetin combined with 0 or 0.1 mg·L−1 (0.54 μM) NAA. Callus induction commenced within a week, independent of the treatments. Callus growth and plant regeneration, however, were significantly influenced by interactions among experimental factors. Generally, the greatest callus growth and plant regeneration were obtained with 0.5 mg·L−1 (2.26 μM) 2,4-D and decreased with increasing 2,4-D concentrations. Kinetin enhanced callus growth only when combined with 0.5 mg·L−1 (2.26 μM) 2,4-D, and 4% sucrose. Inducing callus on kinetin-containing medium generally enhanced regeneration capacity in the presence of sucrose but not with a sucrose/sorbitol combination. Media containing sucrose alone generally supported more callus proliferation, but the sucrose/sorbitol combination improved regeneration of some cultivars. NAA and kinetin had little effect on regeneration.

This study describes the isolation of temperate B. anthracis phages, from 4 out of 20 B. anthracis strains screened, by use of the inducing agents mitomycin C and UV light. Phage phi 20 isolated from B. anthracis Sterne 34F2 (pXO1+ pXO2-) was shown to have double-stranded DNA of size 48756 bp and a restriction site map showing nine sites for enzymes BamHI, BglII, and SstI is included. The phi 20 genome was found to exist as a plasmidial prophage and the phage itself to have a polyhedral head of diameter 65 nm and tail 217 nm long and 15 nm wide.

A micropropagation system was developed forAcacia mearnsii De Wild., which is the principal source of the world’s tanbark and an excellent firewood. Shoot tips 5-mm long from 3-wk-old seedlings germinated in vitro served as explants. The seeds were germinated on hormone-free MS medium and the shoot tips were cultured on three-fourth-strength MS medium supplemented with combinations of auxins [indole-3-butyric acid (IBA) andα-naphthaleneacetic acid (NAA)] and cytokinins [kinetin and benzylaminopurine (BAP)]. Cultures were maintained at 25° ± 5° C and exposed to 12-h photoperiods of cool-white fluorescent light (70 µEm−2·s−1). Multiple shoot formation was promoted by BAP at 2 mg · liter−1 (8.87µM) and higher combined with or without 0.01 mg · liter−1 (0.049µM) IBA. Cytokinins at concentrations of less than 1 mg · liter−1 combined with 0.01 to 0.1 mg · liter−1 auxin inhibited multiple shoot formation and promoted rooting of the shoot tip explants. Shoot multiplication cultures were maintained by transferring segments of multiple-shoot clusters onto a medium containing 2 mg · liter−1 BAP and 0.01 mg · liter−1 IBA. Although higher levels of BAP promoted more multiple shoot formation, this BAP level allowed shoot elongation as well as multiplication. In-vitro-produced shoots were induced to root on a range of NAA concentrations (0.0 to 0.8 mg · liter−1[4.3µM]) supplemented to half- or full-strength MS medium. The highest frequency of root proliferation was on half-strength MS medium supplemented with 0.6 mg · liter−1 (3.22µM) NAA. Plantlets survived in potting soil and exhibited normal growth under greenhouse conditions.

A system for the regeneration of spinach (Spinacia oleracea L.) from mature dry seed explants has been established. The response of two commercial spinach cultivars, ‘Grandstand’ and ‘Baker’, was examined. Callus proliferation was most prominent on MS medium supplemented with 9.3 μM of 6-furfurylaminopurine (kinetin) and 3.39 μM 2,4-dichlorophenoxyacetic acid (2,4-D). Adventitious shoot formation was observed within 8 wk after callus was transferred onto regeneration medium. Shoot regeneration was best from callus induced on 9.3 μM kinetin and 4.56 μM 2,4-D. The regeneration medium contained 9.3 μM kinetin, 0.045 μM 2,4-D, and 2.89 μM gibberellic acid (GA3). Shoots were rooted on hormone-free medium, and plants grown in a greenhouse showed normal phenotype. This system is beneficial in rapid propagation of spinach plants, particularly when only a limited number of seeds are available.