Multiplication Rate Research Articles

Biological performance of Bollgard II® Bt-resistant vs susceptible population of pink bollworm, Pectinophora gossypiella (Saunders) on non-toxic diet

BackgroundThe pink bollworm, Pectinophora gossypiella (Saunders), is a devastating global pest of cotton that has caused substantial economic damage to Bt Bollgard-II® cotton plants in recent years due to the evolution of Bt resistance. The associated fitness cost is assumed to be one of the factors delaying the development of resistance against Bt transgenic crops. Hence, the present study was undertaken to assess the biological performance of pink bollworms by comparing the life history and demographic parameters of a resistant (Field-R) and susceptible (Lab-S) population.ResultsProlonged larval duration (23.40 days in Field-R vs 18.80 days in Lab-S population), total life cycle (male = 50.00 vs 42.80 days; female = 53.60 vs 46.20 days), reduced fecundity (100.60 vs 154.20 eggs/female) and fertility (88.00 vs 138.00 fertile eggs/female) was observed. The demographic parameters indicated a significant reduction in the net reproductive rate (184.27 vs 276.72), innate capacity for increase in number (0.11 vs 0.15), finite rate of increase in number (1.12 vs 1.16 female progenies produced/female/day), weekly multiplication rate (2.16 vs 2.86), potential fecundity (545.06 vs 634.11 eggs), number of hypothetical F2 females (33 955.65 vs 76 572.41), but longer mean length of generation (47.54 vs 37.74 days) and population doubling time (6.30 vs 4.62 days) in Field-R compared with Lab-S population. A stage-specific life table demonstrated the differences in survival rates between susceptible and resistant populations at various life stages, with the resistant population having higher generation mortality (0.22 vs 0.19).ConclusionsThe study confirms the involvement of fitness costs associated with Bt resistance in P. gossypiella. Despite reduced reproductive fitness, the resistant population tried prolonging the larval stage as a compensatory mechanism to repair the damaged host tissues due to Bt intoxication and for accumulation of enough nutrient reserves for normal pupation and adult emergence. Presence of a high proportion of double Bt-resistant larvae in the field coupled with continued noncompliance with refug planting certainly favours the flaring up of this monophagous pest despite the observed fitness costs. The resistance cannot be effectively reversed unless suitable alternative management strategies are deployed.

Refinement of the in vitro propagation process of Petunia (Petunia hybrida) plant

Petunia (Petunia hybrida) is currently one of the most favored ornamental potted flowers. Tissue culture-based propagation has proven to be effective in terms of multiplication rates and consistent seedling quality, meeting the demand for Purple Petunia varieties. In this study, Sodium hypochlorite (NaOCl) with various culture media [Murashige and Skoog (MS), ½ MS, and Knudson C] and growth regulators [6-benzyladenine (BA), Indole 3-butyric acid (IBA), and Naphthaleneacetic acid (NAA)] were utilized to determine the appropriate concentrations and durations for sample sterilization, shoot multiplication, and root induction processes of Purple Petunia. Evaluation criteria for in vitro Purple Petunia included parameters, such as survival rate, contamination rate, dead samples, number of shoots, shoot height, number of roots, and root length. The results indicated that stem sample sterilization at a 5% NaOCl concentration for 10 min yielded the highest survival rate (70.7%) at 14 days post-culture initiation. Purple Petunia stem samples, when cultured in MS medium supplemented with 0.5 mg/L BA combined with 0.1 mg/L IBA, demonstrated the most efficient shoot multiplication with a multiplication rate of 26.9, a shoot weight of 3.6 g, a leaf/shoot ratio of 4.6, and a shoot height of 3.0 cm. The MS medium supplemented with 0.1 mg/L NAA was found to be optimal for root induction, resulting in the highest number of roots at 32.1 roots/plant and a root length of 7.0 cm. Briefly, this research provided fundamental insights into the in vitro propagation process of disease-free Purple Petunia multiplication.

Development of plant-based yogurt from munguba (Pachira aquatica) seeds: Stability and predictive growth of lactic acid cultures

Lactic fermentation is employed to enhance the nutritional quality of plant-based milks, and exploring underutilized plant matrices like munguba (Pachira aquatica) can bring innovation to the plant-based beverage market. This study aimed to develop a yogurt from munguba seeds and investigate the fermentation kinetics of lactic acid bacteria (LAB), as well as the product's stability during storage. Munguba seed milk was prepared through cleaning, peeling, blanching, blending, filtering, and storing at 5 °C. Fermentation was conducted with Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Lactobacillus fermentum at 36 °C, and microbial growth was monitored to construct a LAB growth curve. Ultra High Temperature (UHT) whole cow's milk was used for comparison. Munguba seed milk fermented for 9 h showed LAB growth from 3.89 to 8.22 log CFU/mL, while UHT cow's milk fermented for 6 h showed LAB growth from 4.55 to 6.33 log CFU/mL. The Baranyi model showed good fits for both data sets (R2 of 0.9528 for munguba milk and 0.9340 for UHT milk). Specific growth rates, doubling times, and multiplication rates were higher for munguba milk (μ of 1.10 h^-1, td of 0.66 h, MR of 1.59 h^-1) compared to UHT milk (μ of 0.85 h^-1, td of 0.84 h, MR of 1.22 h^-1). LAB, mold, and yeast counts, pH, and lactic acid content remained stable over 31 days of refrigerated storage of munguba seed yogurt. These results indicate that munguba seed milk is a promising substrate for fermented beverages and beneficial microorganisms.

Hybrid Coffee (<i>Coffea arabica</i> L) Plantlet Production via Indirect Somatic Embryogenesis in Ethiopia: Current Statue and Future Direction

Traditional hybrid coffee propagation methods using seed or vegetative cuttings has tremendous limitations. Seed propagation is associated with hand pollination which is time consuming and need large number of skilled labor. On the other hand, vegetative cuttings ensure uniformity, but; cuttings generate relatively low multiplication rates as they can only be obtained from orthotropic branches. Multiplication by tissue culture techniques could provide a best alternative to these traditional methods of coffee propagation as it allowed the production of relatively uniform plantlets on a large scale in a shorter period in any climatic condition. Among tissue culture techniques, indirect somatic embryogenesis of hybrid coffee plays substantial role in rapid industrial scale multiplication of high valued varities. Research on somatic embryogenesis of <i>C. arabica</i> hybrid has been conducted since the late 70s with the objectives to substitute the conventional vegetative propagation of selected varieties. In Ethiopia, in vitro propagation of hybrid coffee is recent phenomenon and research on indirect somatic embryogenesis is already well underway by different research groups. Here, we discussed the current status of coffee research on somatic embryogenesis in general and specifically, we provide recommendations for future research for the establishment of mass propagation protocol for F1 hybrids varities in Ethiopia that utilized wild endogenous lines.

New insights into synergistic interactions of root-knot nematode and wilt causing fungi on pigeon pea in sandy loam soil

AbstractA study under pot conditions was undertaken to know the relationship between plant biomass and inoculum densities of Meloidogyne incognita. Similarly, plant biomass—Fusarium udum relationship was also observed. Results revealed that increased inoculum densities resulted in corresponding decrease in plant biomass markers. Compared to control plants, 2000 nematode inoculation caused significant damage in phytobiomass (23.07–26.32%) of pigeon pea. 2.0 g F. udum inoculation caused significant impairment in different plant growth characteristics (22.96–26.02%) over control plants at P < 0.05. The interactive study revealed that concomitant, M. incognita + F. udum inoculation caused the maximum reduction (33.68–56.66%) in plant biomass. Next to this, M. incognita inoculation 15 days prior to F. udum and F. udum inoculation 15 days prior to M. incognita caused an impairment of (28.55–50.11%) and (23.99–43.33%), respectively. However, they were statistically either at par or non-significant over each other. Disease assay revealed that M. incognita multiplication rate was correspondingly augmented upon the rise of nematode concentration, conversely, the reproduction factor was progressively decreased. Pathogens interactive facet revealed that M. incognita inoculated plants showed a higher root galls (99.40), eggs (79.20), fecundity (199.80), and nematode population (13,785.60). The presence of F. udum suppressed nematode multiplication ability. However, concomitant inoculation of M. incognita and F. udum aggravated percent wilt severity (65.48%) thus exhibiting a synergistic interaction between the vascular pathogens.

Optimization of thermal management performance of direct-cooled power battery based on backpropagation neural network and deep reinforcement learning

The batteries of new energy vehicles generate a large amount of heat when discharged at large multiplication rates, which can cause safety hazards if the heat is not eliminated in time. In this paper, a Swiss roll-type cooling belt is used to improve the thermal performance of lithium-ion battery packs. This paper selects six key parameters as optimization parameters, including the structure of Swiss roll-type cooling belt, coolant type, inlet coolant mass flow rate, inlet coolant gas volume fraction, battery discharge rate, and ambient temperature. Use neural network fitting and deep reinforcement learning to optimize these six parameters in order to achieve optimized cooling performance. The results show that after the cold plate has been structurally optimised and the inlet parameters have been optimised by deep reinforcement learning, the thermal performance has been significantly improved. Not only does the cold plate inlet require less mass flow, but the battery pack also performs better in terms of temperature difference.

Development of efficient and scalable regeneration tissue culture method for Cannabis sativa

Large scale production of uniform disease-free plants is crucial for Cannabis sativa biotechnology. Existing micropropagation protocols rely heavily on shoot multiplication from existing meristems via direct organogenesis. Such protocols do not allow multiplication of plant material through continuous sub-culturing. Protocols that use indirect regeneration are usually not efficient enough and have very low multiplication rates. In the present study, an efficient protocol that uses a combination of direct organogenesis and callogenesis to induce multiple shoot development cultures is developed. Callogenesis was induced from various explants cultured on the media having various combinations of thidiazuron (TDZ) and naphthaleneacetic acid (NAA); best callogenesis and shoot regeneration was achieved from hypocotyl explants cultured on TDZ 0.4mgl-1 NAA 0.2mgl-1. Hypocotyls with cotyledonary node and shoot apical meristem were significantly better for shoot regeneration than explants without it. Shoots obtained from multiple shoot cultures were successfully rooted and then acclimatized under greenhouse conditions to develop into adult cannabis plants.

Spatial spread of Ditylenchus gigas and its interaction with Botrytis fabae on Vicia faba

AbstractDitylenchus gigas Vovlas is the dominant species of Ditylenchus nematode on faba bean in the UK. It is normally reported with Botrytis fabae Sardiña, which causes chocolate spot of faba bean. The aim of the work reported here was to estimate how fast isolated infections of D. gigas may spread spatially and how background infection of the host with B. fabae alters multiplication of D. gigas. Spatial spread in field conditions was measured in plants growing in square grids. After establishment, single plants at the centre of each grid were spray inoculated with D. gigas. In summer 2017, D. gigas spread to a distance of at least 1 m, the edge of each 2 m × 2 m plot. Incidence on shoots decreased very slowly with distance beyond 0.4 m. In a repeat experiment harvested in autumn 2018, D. gigas was detected at distances of up to 160 cm in 4 m × 4 m plots. The yield effect and reproduction rate of D. gigas were measured in glasshouse experiments, alone and following brush inoculation with low (103) or high (106 conidia/mL) doses of B. fabae. At low doses of D. gigas inoculum multiplied by approximately 75‐fold, with lower rates of multiplication as the inoculum dose increased. The reproduction rate of D. gigas was reduced in plants inoculated with B. fabae, especially at high doses of D. gigas. The reduction was approximately proportional to log (B. fabae dose). Seed yield from inoculated plants decreased approximately in proportion to the logarithms of the initial dose of D. gigas and of B. fabae.

Iron-decorated N/S co-doped porous carbon for sodium-ion battery anode to achieve high initial coulombic efficiency

Hard carbon materials are preferred as anode materials for sodium-ion batteries due to their abundance, low price, and environmental friendliness. However, doping-based modification usually induces low initial coulombic efficiency (ICE), which seriously affects the practical application of carbon materials. In this work, Fe-modified N/S co-doped porous carbon is prepared using the salt template method. Fe, N, and S are uniformly distributed on the porous carbon to form an interwoven network structure, providing abundant active sites. Moreover, during the electrochemical reaction, FeNx effectively catalyzes the generation of solid electrolyte interface (SEI) film, which reduces the consumption of Na+ in the side reaction, leading to a high initial coulombic efficiency, and at the same time, the stabilized SEI film accelerates the diffusion of electrons and ions, effectively enhancing the multiplication rate performance. The NFSC exhibits a high specific capacity (371.3 mAh/g) by the co-coordination strategy and a high ICE (85.9 %). This study provides new ideas for research based on the modification of carbon materials.

Silicon nanoparticle(s) induced morpho-anatomical traits and improved micropropagation of white fleshed dragon fruit [Selenicereus undatus (Haworth)]

Silicon nanoparticles (SiNPs) improve plant growth and yield by enhancing nutrient uptake and stress tolerance. These nanoparticles boost plant defense mechanisms against pathogens and environmental challenges. In this study, seedlings-derived explants of white-fleshed dragon fruit (Selenicereus undatus) were used for differentiation and high-frequency shoot regeneration on Murashige and Skoog (MS) medium with 6-benzylaminopurine (BAP, 0.5 mg L−1) and α-naphthalene acetic acid (NAA, 0.25 mg L−1). The complementation of 3.0 mg L−1 SiNPs in the optimized nutrient medium enhanced the shoot multiplication rate to 23.0 cladodes per explants. The regenerated cladodes were structurally well-suited with thick cuticles, well-developed epidermis, hypodermis, aquiferous cortex, and collateral vascular bundles compared to the control and other concentrations of SiNPs tested. SiNPs promoted the development of 3-5 aerial and adventitious roots per cladode enabling preferred direct hardening of cloned plants on soilrite ex vitro. The morphological transformations improved by SiNPs, including the formation of robust cladode and spines, played a pivotal role in achieving a high rate of acclimatization success (96%) in the field. The incorporation of SiNPs in vitro at the shoot amplification stage of micropropagation of S. undatus induced morphogenesis and structural changes, and promoted qualitative and quantitative improvements in the regenerated cladodes which helped in enhanced survival of plants in vivo.

Pre-Germinative Treatments and In Vitro Germination of Dianthus caryophyllus and Alstroemeria spp. Seeds

Alstroemeria spp. and carnation (Dianthus caryophyllus L.) have considerable and increasing economic importance in the floriculture market, therefore breeders carry out intense breeding programs to select new superior varieties. However, poor germination of hybrid seeds remains a bottleneck. Based on this assumption, seed pre-treatments and in vitro germination protocols, using different germination substrates, were applied in Alstroemeria spp. and carnation to improve germinability. Seed viability was tested using the 2,3,5-triphenyl tetrazolium chloride (TTC) test, and resulted in 91.10% ± 2.33 and 86.66% ± 3.85 in Alstroemeria and carnation, respectively. In Alstroemeria, pre-treatment with potassium nitrate (KNO3) in combination with modified ½ Murashige and Skoog (MS) medium ensured high germination uniformity combined with high germination percentage, showing significantly higher values than the control. In carnation, a suitable seed sterilization procedure was set up (up to 95.8% sterility); treatments with gibberellic acid (GA3) and KNO3 did not influence germination percentage compared to the control. A high multiplication rate of seedling lines was obtained on hormone-free MS medium.

EFFECT OF THE CONCENTRATION OF THE PLANT GROWTH REGULATORS ON IN VITRO SHOOT GROWTH OF BLACKBERRY

Berry fruit species, such as Ribes nigrum, are highly esteemed in numerous countries for their biological and economic value, being regarded as important species of small fruits. Ribes nigrum, indigenous to northern Europe, and northern and central Asia. Conserving species like blackcurrant, as highlighted in the International Scientific reports, is crucial due to their potential health benefits and contributions to maintaining vascular health, especially in postmenopausal populations. The discovery that blackcurrant extract, rich in phytoestrogens, shows promise in preventing elastin degradation and pathological vascular remodeling underscores the importance of preserving this species. In Kazakhstan, the preservation of Ribes nigrum includes various factors, such as ecological significance, local economic value through agriculture, and conservation priorities since blackcurrant plays a significant role in the country's biodiversity and traditional uses. The potential of in vitro propagation for rapid mass production of valuable species is substantial. Our study addresses biodiversity conservation by employing this approach. Specifically, we aimed to investigate the impact of nutrient media and growth regulators on shoot multiplication of Ribes nigrum. Our findings reveal that the optimal concentration of plant growth regulators (PGR) significantly influences both the number and length of shoots. Notably, the highest multiplication rate for Ribes nigrum was achieved on MS with a combination of BAP at 0.5 μ/L and GA 0.5 μ/L. In conclusion, our study elucidates the effects of manipulating PGR concentrations in culture media on Ribes nigrum. We recommend optimizing these concentrations to enhance the growth of Ribes nigrum for potential reintroduction efforts and biodiversity conservation. The research is being conducted as part of program BR21882166, which focuses on the scientific and practical aspects of reproducing, conserving, and utilizing fruit and berry plants from the natural flora of Western, Eastern, Central, and Northern Kazakhstan to ensure food security. This program is financially supported by the Ministry of Science and Higher Education of the Republic of Kazakhstan for the period 2023-2025.

Importance of Media Composition and Explant Type in Cannabis sativa Tissue Culture.

Producing uniform Cannabis sativa (Cannabis) for medicinal/recreational flower production through sexual propagation has been problematic, leading to dominance of clonal propagation from "mother plants" in the cannabinoid industry, which also faces significant limitations. Cannabis tissue culture (TC) methods have been developed to overcome these challenges, but the long-term health and maintenance of Cannabis explants in TC have been largely overlooked in previous studies. The current study focused on the development of an efficient and optimized micropropagation protocol covering the entire process, with a specific focus on the health and performance in the multiplication stage. Multiplication media were formulated hormone-free to avoid longer-term vitrification issues, resulting in single-main-shoot cultures rather than multiple-shoot cultures. This instigated the use of stage II explant types different from the standard shoot tips previously used for multiple shoot cultures. Multiplication media were further improved from the basal salt composition via nitrogen and calcium additives. The optimized protocol was used on eight diverse Cannabis cultivars to test its applicability across various genetic backgrounds. Results indicated that the protocol was effective for conservation purposes across all cultivars and achieved good long-term multiplication rates for some but not all. The outcomes of this study mark a significant stride towards an efficient Cannabis TC methodology ready for more comprehensive industrial applications.

Molecular, structural, and functional characterization of delta subunit of T-complex protein-1 from Leishmania donovani.

Chaperonins/Heat shock protein 60 are ubiquitous multimeric protein complexes that assist in the folding of partially and/or misfolded proteins using metabolic energy into their native stage. The eukaryotic group II chaperonin, also referred as T-complex protein-1 ring complex (TRiC)/T-complex protein-1 (TCP1)/chaperonin containing T-complex protein (CCT), contains 8-9 paralogous subunits, arranged in each of the two rings of hetero-oligomeric complex. In Leishmania, till date, only one subunit, LdTCP1γ, has been well studied. Here, we report the molecular, structural, and functional characterization of TCP1δ subunit of Leishmania donovani (LdTCP1δ), the causative agent of Indian kala-azar. LdTCP1δ gene exhibited only 27.9% identity with LdTCP1γ and clustered in a separate branch in the phylogenic tree of LdTCP1 subunits. The purified recombinant protein formed a high molecular weight complex (0.75 MDa), arranged into 16-mer assembly, and performed in vitro chaperonin activity as assayed by ATP-dependent luciferase folding. LdTCP1δ exhibits 1.8-fold upregulated expression in metabolically active, rapidly dividing log phase promastigotes. Over-expression of LdTCP1δ in promastigotes results in increased infectivity and rate of multiplication of intracellular amastigotes. The study thus establishes the existence of an individual functionally active homo-oligomeric complex of LdTCP1δ chaperonin with its role in parasite infectivity and multiplication.

Microbial interactions modify saffron traits selectively and modulate immunity through adaptive antioxidative strategy: Organic cultivation modules should be trait and crop-specific

Saffron (Crocus sativus L.) is a high-value, low-volume niche cash crop that has the unique ability to synthesize apocarotenoids. Since different biofertilizers are advocated for promoting plant health, we aimed to evaluate the interactions of commercially available microbial inoculants with this unique hysteranthous plant species. We studied the interactive effect of microbial inoculants on agronomical, physiological and biochemical aspects of Crocus growth, corm multiplication and apo-carotenoid biosynthesis. Significant differences in nutrient mobilization potential, induced systemic resistance, plant growth, corm, and stigma yield/quality were detected between the different biofertilizer combinations. The arbuscular mycorrhizal fungi (AMF) + phosphate-solubilizing bacteria (PSB) + potassium-solubilizing bacteria (KSB) combination was the most suitable for enhancing shoot biomass, root depth, and root biomass. Additionally, the average number of flowers per corm, stigma yield, and corm yield were greatest for the same combination. The highest multiplication rate of mother corms and a small corm index were recorded for plants inoculated with Azospirillum + PSB + KSB. Although Azospirillum caused maximum multiplication, the percentage of smaller daughter corms was greater, while the replacement of Azospirillum with AMF resulted in maximum percentage of larger corms. Plant health improved through AMF-mediated microbial interactions, which induced systemic resistance via enzymatic and nonenzymatic mechanisms and increased the uptake of P, K, Cu, Fe, Mn, and Zn. The interrelationship between plant and microbial consortium was complex, causing trait-specific qualitative and quantitative impacts on saffron attributes. Microbial inoculants increased nutrient uptake by saffron plants and triggered biochemical defence response by causing mild stress, making the plant more growth-responsive and better equipped for defence. Microbial interaction increased saffron yield and quality by favourably modulating plant metabolism, majorly overlapping with plant protection mechanisms. However, plant-microbial combinations in an organic production module are trait-specific and should be chosen carefully.

A novel in vitro shoot excision technique for enhancing proliferation in banana cv. Chini Champa

Micropropagation technology has been commercially exploited for mass multiplication of banana. Several parameters such as nutrient media, explants, culture conditions etc have been standardized. However, a novel in vitro shoot excision technique designed to enhance the proliferation rate of banana cv. Chini Champa has been examined for the first time. We meticulously examined the impact of excision angles (45º and 90º) and excision site (Tip, middle and base) during shoot proliferation stage. Our findings unequivocally demonstrate that employing a 45º angle excision and tip excision yield the highest multiplication rates and biomass accumulation, surpassing other excision angles and methods. The substantial enhancement in shoot numbers, growth and biomass underscores the potential of this technique for improving banana propagation protocols, offering a valuable tool for sustainable banana production.

Strain-rate and size dependence of gradient lamellar nickel investigated by in-situ micropillar compression

Strain rate plays a nonnegligible role in the plastic deformation behavior of metallic materials with heterogeneous nanostructure, while little research focuses on the topic. In-situ compression tests at various strain rates were conducted on the micropillars located at different depths from the gradient lamellar Ni. These tests intended to reveal the strain-rate dependence of micropillars with different lamellar thicknesses and illustrated the competitive relationship between strain rate and intrinsic grain size on the plastic deformation behavior of metallic materials. In addition, due to the strain rate sensitivity related to not only intrinsic size but also external size, single Ni micropillars with different diameters were also compressed at various strain rates in order to clarify the competitive relationship between intrinsic size and external size on the strain rate sensitivity. It is found that lamellar thickness rather than strain rate has more effect on plastic deformation, and external size exhibits a more obvious impact on the strain rate sensitivity. The plastic deformation behaviors of different micropillars are mainly explained by transitions in the effect of lamellar grain boundaries on the dislocation motion at various strain rates and over different lamellar thicknesses, resulting in the change of dislocation multiplication and annihilation rate.

The influence of high strain rates on mechanical properties and microstructure of CuCrZr alloy under strong current carrying condition

The extreme condition of high-speed metal deformation under intense current flow is commonly encountered in the realms of national defense, military, and industry. However, there has always been a lack of effective research method for the micro deformation mechanism of metal under this extreme condition. We have developed a high current and high strain rate tensile (HCHST) testing platform based on RC circuits, which is used to research the micro-deformation mechanisms of CuCrZr alloy under this extreme condition. The dynamic tensile tests of CuCrZr alloy at different high strain rates (1401s−1, 2957 s−1, 5503 s−1, 8012 s−1) under the high current density (6550 A/mm2) condition were conducted using the HCHST experimental platform. The mechanical properties and microstructure of CuCrZr alloy under the HCHST were analyzed by combining TEM and EBSD. The research results indicate that the microhardness of the alloy in the HCHST #1 environment (6550 A/mm2,1401s−1) is almost the same as the original state. This is attributed to the strong current promoting the movement of dislocations and reducing the accumulation of dislocations. Under condition like HCHST#1, the dislocation annihilation rate and dislocation formation rate of CuCrZr alloy almost reach equilibrium. At higher strain rates, the dislocation multiplication rate is much higher than the dislocation annihilation rate caused by strong current. This imbalance leads to dislocation entanglement and the formation of dislocation cells, resulting in an increase in the microhardness of the material. Additionally, EBSD was used to analyze the changes in grain size, average volume fraction of LAGBs, average KAM value, and texture of the samples, further verifying the dislocation evolution and microhardness changes of copper alloys under HCHST conditions. Our research results provide strong theoretical for the application of CuCrZr in the field of electrical thermal mechanical coupling.

Direct regeneration-mediated in vitro propagation and microtuberization of potato: An appraisal of the past ten-year period

Potato (Solanum tuberosum L.) is one of the most important food crops widely cultivated worldwide due to its edible and nutrition-rich tubers. It is a temperate crop; however, currently, it is grown in a wide range of areas with distinctive climatic conditions. Traditionally, potato is propagated by whole or cut tubers and true potato seeds. Owing to the low rate of multiplication and high cost of cultivation to produce virus-free planting material during traditional propagation, the in vitro technique becomes an alternative approach to conventional propagation. Over the past ten years, significant advancements have been made in the optimization of protocols for several varieties/cultivars of potato via a direct regeneration-mediated approach. The present short-review illustrates the analysis of an array of significant published findings on various physical and chemical variables that are responsible for fruitful in vitro direct regeneration and microtuberization of potato. Furthermore, this short-review describes a number of undiscovered areas, research gaps, and major problems that might be accounted for advancing noteworthy ingenious approaches associated with potato biotechnology in the near future. The current short-review further addresses salient recommendations and conclusions (based on achievements during the last ten-year period), paving the way for potato researchers to work on several unexplored areas in the coming years.

Experimental vaccination by single dose sporozoite injection of blood-stage attenuated malaria parasites

Malaria vaccination approaches using live Plasmodium parasites are currently explored, with either attenuated mosquito-derived sporozoites or attenuated blood-stage parasites. Both approaches would profit from the availability of attenuated and avirulent parasites with a reduced blood-stage multiplication rate. Here we screened gene-deletion mutants of the rodent parasite P. berghei and the human parasite P. falciparum for slow growth. Furthermore, we tested the P. berghei mutants for avirulence and resolving blood-stage infections, while preserving sporozoite formation and liver infection. Targeting 51 genes yielded 18 P. berghei gene-deletion mutants with several mutants causing mild infections. Infections with the two most attenuated mutants either by blood stages or by sporozoites were cleared by the immune response. Immunization of mice led to protection from disease after challenge with wild-type sporozoites. Two of six generated P. falciparum gene-deletion mutants showed a slow growth rate. Slow-growing, avirulent P. falciparum mutants will constitute valuable tools to inform on the induction of immune responses and will aid in developing new as well as safeguarding existing attenuated parasite vaccines.