Plants produce a wide range of secondary metabolites that play vital roles for their primary functions such as growth, defence, adaptations or reproduction. Some of the plant secondary metabolites are beneficial to mankind as nutraceuticals and pharmaceuticals. Metabolic pathways and their regulatory mechanism are crucial for targeting metabolite engineering. The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated system has been widely applied in genome editing with high accuracy, efficiency, and multiplex targeting ability. Besides its vast application in genetic improvement, the technique also facilitates a comprehensive profiling approach to functional genomics related to gene discovery involved in various plant secondary metabolic pathways. Despite these wide applications, several challenges limit CRISPR/Cas system applicability in genome editing in plants. This review highlights updated applications of CRISPR/Cas system-mediated metabolic engineering of plants and its challenges.

Artemisia vulgaris is an enormously useful aromatic plant known for its insecticidal, antifungal, parasiticidal, and medicinal values. The main aim of this study is to investigate phytochemical contents and the potential antimicrobial activities of Artemisia vulgaris essential oil (AVEO) from the fresh leaves of A. vulgaris grown in Manipur. The AVEO isolated by hydro-distillation from A. vulgaris were analyzed by gas chromatography/mass spectrometry and solid-phase microextraction-GC/MS to describe their volatile chemical profile. There were 47 components identified in the AVEO by GC/MS, amounting to 97.66% of the total composition, while 97.35% were identified by SPME-GC/MS. The prominent compounds present in AVEO analyzed by direct injection and SPME methods are found to be eucalyptol (29.91% and 43.70%), sabinene (8.44% and 8.86%), endo-Borneol (8.24% and 4.76%), 2,7-Dimethyl-2,6-octadien-4-ol (6.76% and 4.24%), and 10-epi-γ-Eudesmol (6.50% and 3.09%). The consolidated component in the leaf volatiles comes to the terms of monoterpenes. The AVEO exhibits antimicrobial activities against fungal pathogens such as Sclerotium oryzae (ITCC 4107) and Fusarium oxysporum (MTCC 9913) and bacterial cultures such as Bacillus cereus (ATCC 13061) and Staphylococcus aureus (ATCC 25923). The percent inhibition of AVEO against the S. oryzae and F. oxysporum was found up to 50.3% and 33.13%, respectively. The MIC and MBC of the essential oil tested for B. cereus and S. aureus were found to be (0.3%, 0.63%) and (0.63%, 2.5%), respectively. Finally, the results revealed that the AVEO characterized by the hydro-distillation and SPME extraction yielded the same chemical profile and showed potent antimicrobial activities. Further research into A. vulgaris’s antibacterial properties can be performed in order to use it as a source for natural antimicrobial medications.

Hyposidra talaca is a major defoliating pest of tea plants in north-eastern part of India. In this study, we look for variations (if any) in the attacking virus. Viral samples were collected from different regions of the northern part of West Bengal in India and were analyzed by PCR technique to study the variations across the region. The partial segment of the HytaNPV polyhedrin gene was cloned and sequenced. A 527 bp nucleotide sequence containing highly conserved region from polyhedrin gene of HytaNPV was observed. The blast homology search for studied polyhedrin gene showed 98% sequence identity with the sequence of previous reported NPV of H. talaca, H. infixaria and Buzura suppressaria. Pathogenicity study against second instar H. talaca indicated that the LC₅₀ values ranged from 4.61 × 10⁵ to 7.57 × 10⁵ polyhedral occlusion bodies per ml (POBs/ml) and the LT₅₀ values ranged from 4.2 to 6.66 days. Sequencing result reveals that the same HytaNPV strain dominates across this area and the pathogenicity indicates its potential as an alternative to chemical insecticides to control H. talaca.