Hail Rihan - Academia.edu (original) (raw)

Papers by Hail Rihan

Plant Growth Regulation, Jul 22, 2015

Effect of photosynthetic photon flux density on growth, photosynthetic competence and antioxidant... more Effect of photosynthetic photon flux density on growth, photosynthetic competence and antioxidant enzymes activity during ex vitro acclimatization of Dieffenbachia cultivars

Journal of Research on the Lepidoptera, 2020

Agronomy

Light emitting diodes (LEDs) are potential light sources for in vitro plant cultures. Here, axill... more Light emitting diodes (LEDs) are potential light sources for in vitro plant cultures. Here, axillary blackberry shoots were grown in MS medium with indole-3-butyric acid (1 mg L−1), naphthalene acetic acid (0.5 mg L−1), and sucrose supplementation (0–60 g L−1) and the cultures were incubated under four light treatments: three LED light treatments (blue + red light (2:1 spectral ratio), blue + red light (1:2), and cool + warm white light (1:1)) and a standard florescent tube white spectrum treatment. Sucrose was indispensable for rooting of blackberry microshoots. Sucrose concentrations up to 45 g L−1 increased total root length and root surface area under all light treatments. However, at this sucrose concentration, leaf area and vegetative growth were negatively affected. Plantlets grown in media containing 15–30 g L−1 of sucrose exhibited the highest leaf pigments, shoot length, and number of leaves. LED treatments increased leaf pigments as compared with florescent treatment. Pla...

Plants, Jan 27, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Plants

Catharanthus roseus L. (G.) Don is the most widely studied plant because of its high pharmacologi... more Catharanthus roseus L. (G.) Don is the most widely studied plant because of its high pharmacological value. In vitro culture uses various plant parts such as leaves, nodes, internodes and roots for inducing callus and subsequent plant regeneration in C. roseus. However, till now, little work has been conducted on anther tissue using plant tissue culture techniques. Therefore, the aim of this work is to establish a protocol for in vitro induction of callus by utilizing anthers as explants in MS (Murashige and Skoog) medium fortified with different concentrations and combinations of PGRs. The best callusing medium contains high α-naphthalene acetic acid (NAA) and low kinetin (Kn) concentrations showing a callusing frequency of 86.6%. SEM–EDX analysis was carried out to compare the elemental distribution on the surfaces of anther and anther-derived calli, and the two were noted to be nearly identical in their elemental composition. Gas chromatography–mass spectrometry (GC–MS) analysis ...

Plants

The demand for medicinal plants is on a rise due to their affordability, accessibility and relati... more The demand for medicinal plants is on a rise due to their affordability, accessibility and relatively non-toxic nature. Combretum molle (Combretaceae) is used in African traditional medicine to treat a number of diseases. This study aimed to screen the phytochemical composition of the hexane, chloroform and methanol extracts of C. molle leaves and stems using qualitative phytochemical screening. Additionally, the study aimed to identify the functional phytochemical groups, determine the elemental composition and provide a fluorescence characterization of the powdered leaves and stems by performing Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX) microanalyses and fluorescence microscopy. Phytochemical screening revealed the presence of alkaloids, flavonoids, phenolic compounds, polyphenols, terpenoids, tannins, coumarins, saponins, phytosterols, gums, mucilage, carbohydrates, amino acids and proteins within all leaf and stem extracts. Lipids and fixed oi...

Animals

In order to manage important transformations affecting a steppe area, it is necessary to analyze ... more In order to manage important transformations affecting a steppe area, it is necessary to analyze the existing pastoral system by evaluating the sustainability of its subsystems of production. For this reason, in this study, a tool for the evaluation of the sustainability of livestock production in the steppe area was used in order to identify the most sustainable systems. The study was conducted using a survey of 87 livestock farmers (production units) in the region ranked first in terms of sheep production. Principal component analysis (PCA) enabled us to identify two production systems: (i) the pastoral production system, characterized by the mobility of livestock and its high dependence on concentrated feed; (ii) the agropastoral system, combining fodder and livestock production, which is sedentary and semi-extensive. Using a grid for evaluating the sustainability of livestock systems in steppe regions, the impact of each system on the environment (environmental, economic, and so...

Plants

Controlled Environment Agriculture (CEA) is a method of increasing crop productivity per unit are... more Controlled Environment Agriculture (CEA) is a method of increasing crop productivity per unit area of cultivated land by extending crop production into the vertical dimension and enabling year-round production. Light emitting diodes (LED) are frequently used as the source of light energy in CEA systems and light is commonly the limiting factor for production under CEA conditions. In the current study, the impact of different spectra was compared with the use of white LED light. The various spectra were white; white supplemented with ultraviolet b for a week before harvest; three combinations of red/blue lights (red 660 nm with blue 450 nm at 1:1 ratio; red 660 nm with blue 435 nm 1:1 ratio; red 660 nm with blue at mix of 450 nm and 435 nm 1:1 ratio); and red/blue supplemented with green and far red (B/R/G/FR, ratio: 1:1:0.07:0.64). The growth, yield, physiological and chemical profiles of two varieties of lettuce, Carmoli (red) and Locarno (green), responded differently to the vario...

Horticulturae

The bio-constituents of medicinal plants are greatly influenced by the environmental conditions a... more The bio-constituents of medicinal plants are greatly influenced by the environmental conditions and growing seasons. This study aimed to uncover the presence of different metabolites and to investigate the biological properties of the leaves of Mangifera indica during summer and winter seasons. The extract of M. indica leaves for summer and winter using different solvent extracts (hexane, chloroform, and methanol) showed the presence of phenols, flavonoids, tannins, terpenoids, alkaloids, phytosterol, saponins, steroids, and carbohydrates. Antibacterial activity of the methanolic leaf extracts for summer and winter were evaluated against the bacterial species Staphylococcus aureus (ATCC 43300) and Escherichia coli (ATCC 25922). For S. aureus (ATTC 43300), the summer crude extract displayed lower antibacterial activity than the control streptomycin, with zones of inhibition of 14.17 and 16.67 mm, respectively. Winter extracts had a zone of inhibition of 12 mm, while streptomycin had ...

Plants

The biosynthesis of silver nanoparticles (AgNPs) from Diospyros villosa leaves and stem bark extr... more The biosynthesis of silver nanoparticles (AgNPs) from Diospyros villosa leaves and stem bark extracts is described. The stem bark AgNPs of D. villosa synthesized at 80 °C (S80) showed good scavenging activity with a lower IC50 value of 8.75 µg·mL−1 compared to ascorbic acid (9.58 µg·mL−1). The total phenol content of the S80 AgNPs was measured and found to be 10.22 ± 0.14 mg.g−1 gallic acid equivalence (GAE). Bacterial growth inhibition (% GI) and violacein inhibition (% VI) of 10.08% and 58.83%, respectively, was observed against C.subtsugae CV017 with leaf AgNPs synthesized at 80 °C (L80) at 80 μg·mL−1. Stem bark AgNPs synthesized at room temperature (SRT) also indicated % GI of 13.83% and % VI of 65.97% against C. subtsugae CV017 at 160 μg·mL−1. Leaf AgNPs of D. villosa synthesized at room temperature (LRT), showed % GI of 29.07% and % VI of 56.53%, respectively, against C. violaceum ATCC 12472 at 320 μg·mL−1. The L80 and SRT at 160 μg·mL−1 and LRT at 320 μg·mL−1 may be considere...

Plants

Diospyros villosa is a perennial species prominently acknowledged for its local medicinal applica... more Diospyros villosa is a perennial species prominently acknowledged for its local medicinal applications. The native utilisation of this species in traditional medicine may be ascribed to the presence of secretory structures and their exudate (comprised of phytochemicals). However, the morphological nature and optical features of the secretory structures in D. villosa remain largely unclear. This study was directed to ascertain the occurrence and adaptive features of structures found within the leaves and stem bark of D. villosa using light and electron microscopy techniques. The current study notes the existence of trichomes, and other secretory structures were noted. SEM indicated the presence of non-glandular hirsute trichomes with bulky stalk on both leaves and stem surfaces. Transverse stem sections revealed the existence of crystal idioblasts. Moreover, the presence of the main phytochemical groups and their localisation within the foliage and stem bark was elucidated through va...

HortTechnology, 2022

Black cumin (Nigella sativa) is an important medicinal plant in the pharmacological industry. It ... more Black cumin (Nigella sativa) is an important medicinal plant in the pharmacological industry. It is cultivated on a commercial scale, but its seeds have a slow, unsynchronized germination rate. Enhancing seed germination is crucial for improving the production of black cumin. The influence of presowing treatments [gibberellic acid (GA3), potassium nitrate, salicylic acid, and stratification at 4 °C] on seed germination was assessed. Seed germination was determined daily for 30 days, and germination parameters, including final germination percentage (FGP), corrected germination rate, number of days to reach 50% of FGP, and seedling length vigor index, were evaluated. Endogenous contents of GA3 and abscisic acid (ABA) in nonstratified and stratified seeds were estimated using high-performance liquid chromatography (HPLC) and seedling growth was determined in 45-day-old seedlings. All presowing treatments tended to boost early germination for the first 10 days compared with the control...

ScienceAsia, 2022

Silver nanoparticles (AgNPs) are sought after by many industries including food industries, heavy... more Silver nanoparticles (AgNPs) are sought after by many industries including food industries, heavy metal sensing, pharmaceutical, and textile. The present study reports on the biosynthesis of silver nanoparticles (AgNPs) and theirs antibacterial activity using a methanolic leaf extract of Heteropyxis natalensis, a native South African medicinal tree. The synthesised particles were characterised by ultraviolet visible spectroscopy (UV-vis), energy dispersive Xray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM), and Fourier transform infrared spectroscopy (FTIR). A colour change of the reaction solution from yellow to brown preliminarily confirmed the presence of AgNPs, and a single absorbance peak at 422 nm, using UV-vis spectroscopy, was the indicative of AgNPs. While EDX revealed the presence of elemental silver in the sample, HRTEM identified spherical AgNPs ranging from 5-60 nm. Hydroxyls, alkynes, alkenes, alkanes, esters, and alkyl halides as possible capping agents of silver ions (Ag +) into AgNPs were identified by FTIR. In addition, AgNPs exhibited antibacterial efficacy against 5 strains of pathogenic bacteria: Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis. The results obtained in this study could potentially benefit future research in nanomedical-driven fields.

Journal of Chemistry, 2022

Callosobruchus maculatus (Fab.) (C. maculatus) is one of the major pests of legume seeds in stora... more Callosobruchus maculatus (Fab.) (C. maculatus) is one of the major pests of legume seeds in storage causing significant damage, leading to food insecurity and low income for farmers. This work was planned to develop eco-friendly agents from essential oils of Artemisia herba alba Asso. (AEO), Maticaria Recutita L. (MEO), and Dittrichia Viscosa L. (DEO) to control C. maculatus. To achieve this goal, essential oils (EOs) were extracted by hydro-distillation using Clevenger apparatus before being characterized by GC-MS. EOs were used for testing purposes using three different tests, namely, inhalation toxicity, contact toxicity, and repellency tests. GC-MS analysis of EOs showed the presence of 16 potentially active compounds in AEO and 38 in MEO, whilst 15 compounds were identified in DEO. AEO was higher in thujone (57.6%) and chrysanthenone (11.8%). Santolina alcohol (40.7%) and germacrene D (8.9%) were the major compounds identified in MEO, whereas isocostic acid (72.3%) was the chie...

Agronomy, 2017

Artificial seeds are artificially encapsulated somatic embryos (usually) or other vegetative part... more Artificial seeds are artificially encapsulated somatic embryos (usually) or other vegetative parts such as shoot buds, cell aggregates, auxiliary buds, or any other micropropagules which can be sown as a seed and converted into a plant under in vitro or in vivo conditions. An improved artificial seed production technique is considered a valuable alternate technology of propagation in many commercially important crops and a significant method for mass propagation of elite plant genotypes. The production of plant clones multiplied by tissue culture and distributed as artificial seeds could be a useful alternative to the costly F1 hybrids for different plant crops. The delivery of artificial seeds also facilitates issues such as undertaking several ways for scaling up in vitro cultures and acclimatization to ex vitro conditions. The development of an artificial seed technique also provides a great approach for the improvement of various plant species such as trees and crops.

Acta Horticulturae, 2015

A reliable method was investigated for high production of cauliflower artificial seeds through so... more A reliable method was investigated for high production of cauliflower artificial seeds through somatic embryogenesis. Optimum Embryogenic callus proliferation was obtained using friable callus derived from hypocotyls and root explants on semisolidified MS (Murashige and Skoog, 1962) media containing 0.15, 0.5 mg/L of 2,4-D and 0.5, 1.0, 2.0 mg/L kinetin. This callus induction medium (CIM) was used to maintain callus tissue by subculturing every 21 days. However, the initiation of liquid cultures from chopped embryogenic clusters and the high production of somatic embryos SEs were established on somatic induction medium (SIM) consisting of MS agitated liquid medium supplemented with 0.05 mg/L IAA, 0.5 mg/L kinetin and 20% sucrose after 20 days. The highest germination and conversion rate 60 and 100%, respectively, was achieved after one month when somatic embryos cultivated on MS medium without hormones. Mature somatic embryos were encapsulated in Ca-alginate beads to produce artificial seeds. The ability of cauliflower SEs to regenerate complete plantlets was discovered.

Plant Cell, Tissue and Organ Culture (PCTOC), 2011

Check the metadata sheet to make sure that the header information, especially author names and th... more Check the metadata sheet to make sure that the header information, especially author names and the corresponding affiliations are correctly shown. • Check the questions that may have arisen during copy editing and insert your answers/ corrections. • Check that the text is complete and that all figures, tables and their legends are included. Also check the accuracy of special characters, equations, and electronic supplementary material if applicable. If necessary refer to the Edited manuscript. • The publication of inaccurate data such as dosages and units can have serious consequences. Please take particular care that all such details are correct. • Please do not make changes that involve only matters of style. We have generally introduced forms that follow the journal's style. Substantial changes in content, e.g., new results, corrected values, title and authorship are not allowed without the approval of the responsible editor. In such a case, please contact the Editorial Office and return his/her consent together with the proof. • If we do not receive your corrections within 48 hours, we will send you a reminder. • Your article will be published Online First approximately one week after receipt of your corrected proofs. This is the official first publication citable with the DOI. Further changes are, therefore, not possible. • The printed version will follow in a forthcoming issue.

Agronomy, 2019

Light is a crucial element for plant growth and production. In areas where natural light is not s... more Light is a crucial element for plant growth and production. In areas where natural light is not sufficient for optimal plant growth and production, high pressure sodium (HPS) light sources are widely used. However, HPS lamps are considered not very electrically efficient generating high radiant heat and as a consequence, there has been a lot of interest in replacing HPS lamps with new more efficient lighting sources in the form of light-emitting diodes (LEDs). The effects of three lighting sources (White LED, Blue/Red LED and HPS) on the growth, development and on the essential oil yield and quality of sweet basil and bush basil were investigated. There was a clear advantage to the Blue/Red (452 nm and 632 nm, respectively) LED on virtually all growth and physiological parameters measured for both basil species. The HPS lighting system always performed least effectively in all comparisons. Combining increases in plant yield and increases in oil yield the Blue/Red LED array outperfor...

This copy of the thesis has been supplied on condition that anyone who consults it is understood ... more This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognize that its copyright rests with its author and that quotation from the thesis and no information derived from it may be published without the author's prior consent XII 5.2.4. The effect of Mo on the induction of CBF/DREB1 expression and on the cold tolerance of acclimated cauliflower microshoots .

VIII International Symposium on In Vitro Culture and Horticultural Breeding, 2015

An effective protocol for cauliflower micropropagation was optimised and developed which enabled ... more An effective protocol for cauliflower micropropagation was optimised and developed which enabled the production of tens of thousands of cauliflower microshoots from one cauliflower curd. The large number of microshoots that can be produced per culture unit facilitates the use of this protocol to analyse both the physiological and molecular components of abiotic stress tolerance. The protocol was used for cauliflower cold tolerance analysis and it was demonstrated that low temperature acclimation increased the cold tolerance of explants. The effect of two additives used with the cauliflower culture media on cold tolerance were evaluated. ABA significantly decreased both cold tolerance in acclimated and non-acclimated cauliflower microshoots whilst molybdenum had a highly positive effect on cold tolerance of cauliflower microshoots. Moreover, molybdenum had the capacity to increase the cold tolerance of cauliflower microshoots without low temperature treatment. This is the first study that confirmed this feature of molybdenum and it is believed that this finding could have an application in the field.

Plant Growth Regulation, Jul 22, 2015

Effect of photosynthetic photon flux density on growth, photosynthetic competence and antioxidant... more Effect of photosynthetic photon flux density on growth, photosynthetic competence and antioxidant enzymes activity during ex vitro acclimatization of Dieffenbachia cultivars

Journal of Research on the Lepidoptera, 2020

Agronomy

Light emitting diodes (LEDs) are potential light sources for in vitro plant cultures. Here, axill... more Light emitting diodes (LEDs) are potential light sources for in vitro plant cultures. Here, axillary blackberry shoots were grown in MS medium with indole-3-butyric acid (1 mg L−1), naphthalene acetic acid (0.5 mg L−1), and sucrose supplementation (0–60 g L−1) and the cultures were incubated under four light treatments: three LED light treatments (blue + red light (2:1 spectral ratio), blue + red light (1:2), and cool + warm white light (1:1)) and a standard florescent tube white spectrum treatment. Sucrose was indispensable for rooting of blackberry microshoots. Sucrose concentrations up to 45 g L−1 increased total root length and root surface area under all light treatments. However, at this sucrose concentration, leaf area and vegetative growth were negatively affected. Plantlets grown in media containing 15–30 g L−1 of sucrose exhibited the highest leaf pigments, shoot length, and number of leaves. LED treatments increased leaf pigments as compared with florescent treatment. Pla...

Plants, Jan 27, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Plants

Catharanthus roseus L. (G.) Don is the most widely studied plant because of its high pharmacologi... more Catharanthus roseus L. (G.) Don is the most widely studied plant because of its high pharmacological value. In vitro culture uses various plant parts such as leaves, nodes, internodes and roots for inducing callus and subsequent plant regeneration in C. roseus. However, till now, little work has been conducted on anther tissue using plant tissue culture techniques. Therefore, the aim of this work is to establish a protocol for in vitro induction of callus by utilizing anthers as explants in MS (Murashige and Skoog) medium fortified with different concentrations and combinations of PGRs. The best callusing medium contains high α-naphthalene acetic acid (NAA) and low kinetin (Kn) concentrations showing a callusing frequency of 86.6%. SEM–EDX analysis was carried out to compare the elemental distribution on the surfaces of anther and anther-derived calli, and the two were noted to be nearly identical in their elemental composition. Gas chromatography–mass spectrometry (GC–MS) analysis ...

Plants

The demand for medicinal plants is on a rise due to their affordability, accessibility and relati... more The demand for medicinal plants is on a rise due to their affordability, accessibility and relatively non-toxic nature. Combretum molle (Combretaceae) is used in African traditional medicine to treat a number of diseases. This study aimed to screen the phytochemical composition of the hexane, chloroform and methanol extracts of C. molle leaves and stems using qualitative phytochemical screening. Additionally, the study aimed to identify the functional phytochemical groups, determine the elemental composition and provide a fluorescence characterization of the powdered leaves and stems by performing Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX) microanalyses and fluorescence microscopy. Phytochemical screening revealed the presence of alkaloids, flavonoids, phenolic compounds, polyphenols, terpenoids, tannins, coumarins, saponins, phytosterols, gums, mucilage, carbohydrates, amino acids and proteins within all leaf and stem extracts. Lipids and fixed oi...

Animals

In order to manage important transformations affecting a steppe area, it is necessary to analyze ... more In order to manage important transformations affecting a steppe area, it is necessary to analyze the existing pastoral system by evaluating the sustainability of its subsystems of production. For this reason, in this study, a tool for the evaluation of the sustainability of livestock production in the steppe area was used in order to identify the most sustainable systems. The study was conducted using a survey of 87 livestock farmers (production units) in the region ranked first in terms of sheep production. Principal component analysis (PCA) enabled us to identify two production systems: (i) the pastoral production system, characterized by the mobility of livestock and its high dependence on concentrated feed; (ii) the agropastoral system, combining fodder and livestock production, which is sedentary and semi-extensive. Using a grid for evaluating the sustainability of livestock systems in steppe regions, the impact of each system on the environment (environmental, economic, and so...

Plants

Controlled Environment Agriculture (CEA) is a method of increasing crop productivity per unit are... more Controlled Environment Agriculture (CEA) is a method of increasing crop productivity per unit area of cultivated land by extending crop production into the vertical dimension and enabling year-round production. Light emitting diodes (LED) are frequently used as the source of light energy in CEA systems and light is commonly the limiting factor for production under CEA conditions. In the current study, the impact of different spectra was compared with the use of white LED light. The various spectra were white; white supplemented with ultraviolet b for a week before harvest; three combinations of red/blue lights (red 660 nm with blue 450 nm at 1:1 ratio; red 660 nm with blue 435 nm 1:1 ratio; red 660 nm with blue at mix of 450 nm and 435 nm 1:1 ratio); and red/blue supplemented with green and far red (B/R/G/FR, ratio: 1:1:0.07:0.64). The growth, yield, physiological and chemical profiles of two varieties of lettuce, Carmoli (red) and Locarno (green), responded differently to the vario...

Horticulturae

The bio-constituents of medicinal plants are greatly influenced by the environmental conditions a... more The bio-constituents of medicinal plants are greatly influenced by the environmental conditions and growing seasons. This study aimed to uncover the presence of different metabolites and to investigate the biological properties of the leaves of Mangifera indica during summer and winter seasons. The extract of M. indica leaves for summer and winter using different solvent extracts (hexane, chloroform, and methanol) showed the presence of phenols, flavonoids, tannins, terpenoids, alkaloids, phytosterol, saponins, steroids, and carbohydrates. Antibacterial activity of the methanolic leaf extracts for summer and winter were evaluated against the bacterial species Staphylococcus aureus (ATCC 43300) and Escherichia coli (ATCC 25922). For S. aureus (ATTC 43300), the summer crude extract displayed lower antibacterial activity than the control streptomycin, with zones of inhibition of 14.17 and 16.67 mm, respectively. Winter extracts had a zone of inhibition of 12 mm, while streptomycin had ...

Plants

The biosynthesis of silver nanoparticles (AgNPs) from Diospyros villosa leaves and stem bark extr... more The biosynthesis of silver nanoparticles (AgNPs) from Diospyros villosa leaves and stem bark extracts is described. The stem bark AgNPs of D. villosa synthesized at 80 °C (S80) showed good scavenging activity with a lower IC50 value of 8.75 µg·mL−1 compared to ascorbic acid (9.58 µg·mL−1). The total phenol content of the S80 AgNPs was measured and found to be 10.22 ± 0.14 mg.g−1 gallic acid equivalence (GAE). Bacterial growth inhibition (% GI) and violacein inhibition (% VI) of 10.08% and 58.83%, respectively, was observed against C.subtsugae CV017 with leaf AgNPs synthesized at 80 °C (L80) at 80 μg·mL−1. Stem bark AgNPs synthesized at room temperature (SRT) also indicated % GI of 13.83% and % VI of 65.97% against C. subtsugae CV017 at 160 μg·mL−1. Leaf AgNPs of D. villosa synthesized at room temperature (LRT), showed % GI of 29.07% and % VI of 56.53%, respectively, against C. violaceum ATCC 12472 at 320 μg·mL−1. The L80 and SRT at 160 μg·mL−1 and LRT at 320 μg·mL−1 may be considere...

Plants

Diospyros villosa is a perennial species prominently acknowledged for its local medicinal applica... more Diospyros villosa is a perennial species prominently acknowledged for its local medicinal applications. The native utilisation of this species in traditional medicine may be ascribed to the presence of secretory structures and their exudate (comprised of phytochemicals). However, the morphological nature and optical features of the secretory structures in D. villosa remain largely unclear. This study was directed to ascertain the occurrence and adaptive features of structures found within the leaves and stem bark of D. villosa using light and electron microscopy techniques. The current study notes the existence of trichomes, and other secretory structures were noted. SEM indicated the presence of non-glandular hirsute trichomes with bulky stalk on both leaves and stem surfaces. Transverse stem sections revealed the existence of crystal idioblasts. Moreover, the presence of the main phytochemical groups and their localisation within the foliage and stem bark was elucidated through va...

HortTechnology, 2022

Black cumin (Nigella sativa) is an important medicinal plant in the pharmacological industry. It ... more Black cumin (Nigella sativa) is an important medicinal plant in the pharmacological industry. It is cultivated on a commercial scale, but its seeds have a slow, unsynchronized germination rate. Enhancing seed germination is crucial for improving the production of black cumin. The influence of presowing treatments [gibberellic acid (GA3), potassium nitrate, salicylic acid, and stratification at 4 °C] on seed germination was assessed. Seed germination was determined daily for 30 days, and germination parameters, including final germination percentage (FGP), corrected germination rate, number of days to reach 50% of FGP, and seedling length vigor index, were evaluated. Endogenous contents of GA3 and abscisic acid (ABA) in nonstratified and stratified seeds were estimated using high-performance liquid chromatography (HPLC) and seedling growth was determined in 45-day-old seedlings. All presowing treatments tended to boost early germination for the first 10 days compared with the control...

ScienceAsia, 2022

Silver nanoparticles (AgNPs) are sought after by many industries including food industries, heavy... more Silver nanoparticles (AgNPs) are sought after by many industries including food industries, heavy metal sensing, pharmaceutical, and textile. The present study reports on the biosynthesis of silver nanoparticles (AgNPs) and theirs antibacterial activity using a methanolic leaf extract of Heteropyxis natalensis, a native South African medicinal tree. The synthesised particles were characterised by ultraviolet visible spectroscopy (UV-vis), energy dispersive Xray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM), and Fourier transform infrared spectroscopy (FTIR). A colour change of the reaction solution from yellow to brown preliminarily confirmed the presence of AgNPs, and a single absorbance peak at 422 nm, using UV-vis spectroscopy, was the indicative of AgNPs. While EDX revealed the presence of elemental silver in the sample, HRTEM identified spherical AgNPs ranging from 5-60 nm. Hydroxyls, alkynes, alkenes, alkanes, esters, and alkyl halides as possible capping agents of silver ions (Ag +) into AgNPs were identified by FTIR. In addition, AgNPs exhibited antibacterial efficacy against 5 strains of pathogenic bacteria: Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis. The results obtained in this study could potentially benefit future research in nanomedical-driven fields.

Journal of Chemistry, 2022

Callosobruchus maculatus (Fab.) (C. maculatus) is one of the major pests of legume seeds in stora... more Callosobruchus maculatus (Fab.) (C. maculatus) is one of the major pests of legume seeds in storage causing significant damage, leading to food insecurity and low income for farmers. This work was planned to develop eco-friendly agents from essential oils of Artemisia herba alba Asso. (AEO), Maticaria Recutita L. (MEO), and Dittrichia Viscosa L. (DEO) to control C. maculatus. To achieve this goal, essential oils (EOs) were extracted by hydro-distillation using Clevenger apparatus before being characterized by GC-MS. EOs were used for testing purposes using three different tests, namely, inhalation toxicity, contact toxicity, and repellency tests. GC-MS analysis of EOs showed the presence of 16 potentially active compounds in AEO and 38 in MEO, whilst 15 compounds were identified in DEO. AEO was higher in thujone (57.6%) and chrysanthenone (11.8%). Santolina alcohol (40.7%) and germacrene D (8.9%) were the major compounds identified in MEO, whereas isocostic acid (72.3%) was the chie...

Agronomy, 2017

Artificial seeds are artificially encapsulated somatic embryos (usually) or other vegetative part... more Artificial seeds are artificially encapsulated somatic embryos (usually) or other vegetative parts such as shoot buds, cell aggregates, auxiliary buds, or any other micropropagules which can be sown as a seed and converted into a plant under in vitro or in vivo conditions. An improved artificial seed production technique is considered a valuable alternate technology of propagation in many commercially important crops and a significant method for mass propagation of elite plant genotypes. The production of plant clones multiplied by tissue culture and distributed as artificial seeds could be a useful alternative to the costly F1 hybrids for different plant crops. The delivery of artificial seeds also facilitates issues such as undertaking several ways for scaling up in vitro cultures and acclimatization to ex vitro conditions. The development of an artificial seed technique also provides a great approach for the improvement of various plant species such as trees and crops.

Acta Horticulturae, 2015

A reliable method was investigated for high production of cauliflower artificial seeds through so... more A reliable method was investigated for high production of cauliflower artificial seeds through somatic embryogenesis. Optimum Embryogenic callus proliferation was obtained using friable callus derived from hypocotyls and root explants on semisolidified MS (Murashige and Skoog, 1962) media containing 0.15, 0.5 mg/L of 2,4-D and 0.5, 1.0, 2.0 mg/L kinetin. This callus induction medium (CIM) was used to maintain callus tissue by subculturing every 21 days. However, the initiation of liquid cultures from chopped embryogenic clusters and the high production of somatic embryos SEs were established on somatic induction medium (SIM) consisting of MS agitated liquid medium supplemented with 0.05 mg/L IAA, 0.5 mg/L kinetin and 20% sucrose after 20 days. The highest germination and conversion rate 60 and 100%, respectively, was achieved after one month when somatic embryos cultivated on MS medium without hormones. Mature somatic embryos were encapsulated in Ca-alginate beads to produce artificial seeds. The ability of cauliflower SEs to regenerate complete plantlets was discovered.

Plant Cell, Tissue and Organ Culture (PCTOC), 2011

Check the metadata sheet to make sure that the header information, especially author names and th... more Check the metadata sheet to make sure that the header information, especially author names and the corresponding affiliations are correctly shown. • Check the questions that may have arisen during copy editing and insert your answers/ corrections. • Check that the text is complete and that all figures, tables and their legends are included. Also check the accuracy of special characters, equations, and electronic supplementary material if applicable. If necessary refer to the Edited manuscript. • The publication of inaccurate data such as dosages and units can have serious consequences. Please take particular care that all such details are correct. • Please do not make changes that involve only matters of style. We have generally introduced forms that follow the journal's style. Substantial changes in content, e.g., new results, corrected values, title and authorship are not allowed without the approval of the responsible editor. In such a case, please contact the Editorial Office and return his/her consent together with the proof. • If we do not receive your corrections within 48 hours, we will send you a reminder. • Your article will be published Online First approximately one week after receipt of your corrected proofs. This is the official first publication citable with the DOI. Further changes are, therefore, not possible. • The printed version will follow in a forthcoming issue.

Agronomy, 2019

Light is a crucial element for plant growth and production. In areas where natural light is not s... more Light is a crucial element for plant growth and production. In areas where natural light is not sufficient for optimal plant growth and production, high pressure sodium (HPS) light sources are widely used. However, HPS lamps are considered not very electrically efficient generating high radiant heat and as a consequence, there has been a lot of interest in replacing HPS lamps with new more efficient lighting sources in the form of light-emitting diodes (LEDs). The effects of three lighting sources (White LED, Blue/Red LED and HPS) on the growth, development and on the essential oil yield and quality of sweet basil and bush basil were investigated. There was a clear advantage to the Blue/Red (452 nm and 632 nm, respectively) LED on virtually all growth and physiological parameters measured for both basil species. The HPS lighting system always performed least effectively in all comparisons. Combining increases in plant yield and increases in oil yield the Blue/Red LED array outperfor...

This copy of the thesis has been supplied on condition that anyone who consults it is understood ... more This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognize that its copyright rests with its author and that quotation from the thesis and no information derived from it may be published without the author's prior consent XII 5.2.4. The effect of Mo on the induction of CBF/DREB1 expression and on the cold tolerance of acclimated cauliflower microshoots .

VIII International Symposium on In Vitro Culture and Horticultural Breeding, 2015

An effective protocol for cauliflower micropropagation was optimised and developed which enabled ... more An effective protocol for cauliflower micropropagation was optimised and developed which enabled the production of tens of thousands of cauliflower microshoots from one cauliflower curd. The large number of microshoots that can be produced per culture unit facilitates the use of this protocol to analyse both the physiological and molecular components of abiotic stress tolerance. The protocol was used for cauliflower cold tolerance analysis and it was demonstrated that low temperature acclimation increased the cold tolerance of explants. The effect of two additives used with the cauliflower culture media on cold tolerance were evaluated. ABA significantly decreased both cold tolerance in acclimated and non-acclimated cauliflower microshoots whilst molybdenum had a highly positive effect on cold tolerance of cauliflower microshoots. Moreover, molybdenum had the capacity to increase the cold tolerance of cauliflower microshoots without low temperature treatment. This is the first study that confirmed this feature of molybdenum and it is believed that this finding could have an application in the field.