Phytochemical diversity of Murraya koenigii (L.) Spreng. from Western Himalaya.

Murraya koenigii (L.) Spreng. (Rutaceae), commonly known as 'curry leaf tree', is a popular spice and condiment of India. To explore the diversity of the essential-oil yield and aroma profile of curry leaf, growing wild in foot and mid hills of north India, 58 populations were collected during spring season. M. koenigii populations were found to grow up to an altitude of 1487 m in north India. Comparative results showed considerable variations in the essential-oil yield and composition. The essential-oil yield varied from 0.14 to 0.80% in shade-dried leaves of different populations of M. koenigii. Analysis of the essential oils by GC and GC/MS, and the subsequent classification by statistical analysis resulted in four clusters with significant variations in their terpenoid composition. Major components of the essential oils of investigated populations were α-pinene (2; 4.5-71.5%), sabinene (3; <0.05-66.1%), (E)-caryophyllene (11; 1.6-18.0%), ß-pinene (4; <0.05-13.6%), terpinen-4-ol (9; 0.0-8.4%), γ-terpinene (8; 0.2-7.4%), limonene (7; 1.1-5.5%), α-terpinene (6; 0.0-4.5%), (E)-nerolidol (14; 0.0-4.1%), α-humulene (12; 0.6-3.5%), α-thujene (1; 0.0-2.5%), ß-elemene (10; 0.2-2.4%), ß-selinene (13; 0.2-2.3%), and myrcene (5; 0.5-2.1%). Comparison of the present results with those in earlier reports revealed new chemotypes of M. koenigii in investigated populations from Western Himalaya. The present study documents M. koenigii populations having higher amounts of sabinene (3; up to 66.1%) for the first time.

Nanomaterial based gene delivery: a promising method for plant genome engineering.

Nanomaterials have attracted considerable attention from researchers in recent years due to their unique architecture and small dimensions. Significant progress has been made in the therapeutics, diagnostics, and delivery of biomolecules in animal cells. However, nanotechnology is still in its infancy in plant science. Nanotechnology offers tremendous opportunities for crop improvement and would make significant contributions to increase agricultural productivity. There are several reports where nanomaterial-induced improvement of the agronomic traits has been successfully achieved. However, very little is known about the interactions of nanomaterials with plant cells and the mechanism of internalization and delivery of biomolecules using nanoparticles as a carrier. Due to the presence of the cell wall, the delivery of biomolecules such as nucleic acids is a major challenge, which limits the application of nanomaterials in genetic engineering-mediated crop improvement. However, in recent years, the use of various nanomaterials like carbon nanotubes, magnetic nanoparticles, mesoporous silica nanoparticles, etc. for nucleic acid delivery in plant cells has been reported as proof of concept. Here, we intend to update researchers about the use of various nanomaterials as a novel gene delivery tool for plant genetic engineering. This review also explores the progress made in nanoparticle-mediated nucleic acid delivery in plant cells and their role in plant genome engineering.