Compared to seeds and mature plants, sprouts are well characterized based on their nutritive values and biological properties. Moreover, laser light application is known to be a promising approach to improving plant growth, photosynthesis, and nutraceutical values. However, no studies have investigated the phytochemicals and biological activity of lemongrass (Cymbopogon proximus (Hochst. ex A.Rich.) Chiov.) sprouts or the further improvement of their quality by applying laser light treatment. We carried out a preliminary experiment for the optimization of laser treatment conditions, finding that a helium neon (He–Ne) laser at 632 nm and 5 mW for 5 min provided the most favorable conditions. We then investigated fresh weight, photosynthetic reactions, and primary and secondary metabolites, including sugars, amino acids, organic acids, essential oils, and phenolic compounds. Moreover, we studied the effect of laser light-induced changes in chemical compositions on the antioxidant, anti-diabetic, and anti-cholesterol activities of Cymbopogon proximus sprouts grown from laser-treated seeds. Laser light treatment increased the photosynthesis and respiration and hence the fresh weight of Cymbopogon proximus sprouts. Overall, sprouting increased most bioactive primary and secondary metabolites as compared to seeds. Increased photosynthesis by laser light improved carbon allocation and raised non-structural carbohydrates, which in turn led to improved synthesis of amino acids, organic acids, and essential oils, as well as phenolic and flavonoid compounds. As a result, laser light significantly improved the antioxidant capacity in terms of increasing the levels of ferric reducing antioxidant power (FRAP) (from 9.5 to 21 µmole trolox/g fresh weight (FW)), oxygen radical absorbance (ORAC) (from 400 to 1100 µmole trolox/100 g FW), and DPPH (from 5% to 25% of inhibation) and enhanced the hypocholesterolemic and antidiabetic activity through increasing the percentage of cholesterol micellar solubility (CMS) inhibition (from 42% to 62%) and glycemic index (from 33 to 17 µmole/g) over sprouts and seeds. In conclusion, the synergism of seed laser treatment and sprouting induced the health-promoting bioactive compounds in Cymbopogon proximus as compared to seeds, which can be applied at a large scale to improve the biochemical, physiological, and nutraceutical values of medicinal and crop sprouts.

Tomatoes (Solanum tuberosum L.) are considered one of the most effective and nutritious foods in the human diet. Moreover, the fruit of a tomato is rich in phytochemical compounds such as carotenoids, vitamins, and phenolics which are beneficial to human health. The objective of this present research was to investigate the impact of biogenic Ag-containing nanoparticles on seed germination rate and germination speed index, the development of the stem and root system, and physio-biochemical parameters. Ag-containing nanoparticles were synthesized biologically using a silver nitrate solution and aqueous seed extract of Juniperus procera, which acted as a capping and reducing agent. The impact of different concentrations (0.0, 2.5, 5, 10, and 25 mg/L) of Ag-containing NPs on seed germination rate, biomass accumulation, phenolic compounds, total protein, enzymes activity, and total soluble sugar of tomatoes (Solanum tuberosum L.) in vitro has been tested. The obtained result demonstrated that Ag-containing nanoparticles have a significant impact on tomato seed germination rate, germination speed index, and the development of stem and root systems. As well as photosynthetic pigments, total protein, enzymes activity, phenolic compounds, and total soluble sugar. We concluded that Ag-containing NPs can be a promising nano-fertilizer for improving crop growth and production.

Dry direct-seeded rice (Oryza sativa L.), a climate-smart and resource-efficient (labor and water) rice production technology is gaining popularity in many parts of Asian countries; however, weeds are the major constraints for its early establishment and optimum productivity. Chemical weed management is effective, rapid, and also decreases weed management costs in dry direct-seeded rice (DSR) system; however, chemical use for weed management have a negative effect on the environment and also have human health hazards. Therefore, integrated weed management (IWM) is the best option for the sustainability of rice production under the DSR system. Improving competitiveness against weeds, weed-competitive rice cultivars, and high seeding rates were found to be the most promising IWM strategies in DSR. In this context, a field study was conducted to evaluate the weed competitiveness of rice cultivars and seeding rates on the performance of aus rice in dry direct-seeded systems in Bangladesh. Three inbred rice cultivars (CV), namely “BRRI dhan26”, “BRRI dhan48”, and “BRRI dhan55”, and one hybrid cultivar, “Arize” were tested in a seeding rate (SR) of 20, 40, and 80 kg ha⁻¹ under two weeding regimes (WR) of weed-free and partially-weedy. Rice grain yield was strongly affected (p < 0.01) by the interactions of WR, CV, and SR. In weed-free conditions, the yield of all three inbred cultivars was increased up to SR of 40 kg ha⁻¹ and for the hybrid cultivar, up to SR of 20 kg ha⁻¹, and with further increment of SR, there was no yield advantage. Conversely, under partially weedy conditions, the yield of three inbred cultivars increased up to SR of 80 kg ha⁻¹; however, for the hybrid cultivar, this increment was up to SR of 40 kg ha⁻¹ and thereafter, no yield gain. In weedy conditions, the higher SR compensates for the yield losses by increasing the competitiveness of rice with weeds. Across SR, the hybrid cultivar had a significantly (p < 0.01) higher weed competitive index (WCI) than all the inbred cultivars and the highest SR always had a higher WCI.

Artemisia species are very important medicinal plants, particularly in the Middle East and in developing countries. Their products have been used in traditional and medicine contemporary for the treating of infectious ulcers, gangrenous ulcers, inflammations, and malaria. Artemisinin derived from Artemisia species has been used as a drug in many countries for malaria disease treatment. Hence, this study aimed to identify and evaluate the bioactive compounds of three species of Artemisia (Artemisia judaica, Artemisia monosperma, and Artemisia sieberi) growing in Saudi Arabia. Therefore, several analytical techniques, such as gas chromatography–mass spectrometry (GC-MS), UV-Visible spectrophotometry (UV-Vis), and high-performance liquid chromatography (HPLC), with reference standards, were used. The GC-MS analysis of the artemisia species revealed many bioactive constituents associated with plant secondary metabolites; some of these identified phytochemical components have biological activity. A. Judaica showed the highest number of bioactive compounds, followed by A. sieberi and A. monosperma. Further, the total phenol, total flavonoid, total tannin, terpenoids, and TCA were estimated. Furthermore, biomolecules such gallic acid, tannin acid, quercetin, and artemisinin in different artemisia species were quantified using HPLC with the reference standard. The amount of artemisinin in the leaf extract of these species (A. sieberi, A. Judaica, and A. monosperma) was found to be about 3.01, 2.5, and 1.9 mg/g DW, respectively. Moreover, the antioxidant activity of the samples was estimated. The obtained results have shown that these species possessed high antioxidant activity, and the scavenging of the DPPH radical and hydrogen peroxide were found to be raised with the increase in the plant extract concentration. This reflects the number of bioactive compounds in these species. The findings of this research support and justify the utilization of Artemisia species in folk medicine in the Middle East.

Plectranthus amboinicus (Lour.) Spreng is a perennial plant from the mint family with aromatic, succulent leaves and several health benefits. Multiple shoot regeneration was accomplished in vitro using nodal segments (NS) explants of P. amboinicus pretreated with 0, 0.5, 5, 25, 50, and 100 μM thidiazuron (TDZ) for 4 h, then transferred to a growth regulator-free media. After 8 weeks of growth, NS explants pre-treated with 25 μM TDZ for 4 h and then transferred to TDZ-free Murashige and Skoog (MS) media produced the greatest number of shoots (27.3 per NS) with the longest average shoot length (4.9 mm) in 97.2% of cultures. On the same medium, regeneration of roots in most of the P. amboinicus shoots occurred spontaneously. The in vitro-regenerated P. amboinicus plantlets were adequately hardened off and adapted to the ex-vitro environment with a 90% survival rate. Total phenolic, tannin, and flavonoid contents, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging/antioxidant activity, were significantly higher in in vitro-regenerated plants than in ex vitro-plants. Flow cytometry (FCM) analysis validated the nuclear genome stability of the in vitro generated plants, which assessed their nuclear DNA content and found it to be comparable in genome size to that of the field-grown plants. The study found a quick and efficient method for in vitro multiplication of P. amboinicus which can aid to increased availability and accessibility of this plant species for various purposes. The genetic and phytochemical analysis of the in vitro propagated plants can also provide valuable insight into the plant’s properties and potential applications, which can further assist in its preservation and sustainable usage.