Browsing by Author "Malhotra, Bhanu"

Now showing 1 - 4 of 4

A comprehensive Vis-NIRS equation for rapid quantification of seed glucosinolate content and composition across diverse Brassica oilseed chemotypes
(Elsevier B.V., 2021) Gohain, Bornali; Kumar, Pawan; Malhotra, Bhanu; Augustine, Rehna; Pradhan, Akshay K.; Bisht, Naveen C.
The globally cultivated Brassica crops contain high deliverable concentrations of health-promoting glucosinolates. Development of a Visible-Near InfraRed Spectroscopy (Vis-NIRS) calibration to profile different glucosinolate components from 641 diverse Brassica juncea chemotypes was attempted in this study. Principal component analysis of HPLC-determined glucosinolates established the distinctiveness of four B. juncea populations used. Subsequently, modified partial least square regression based population-specific and combined Vis-NIRS models were developed, wherein the combined model exhibited higher coefficient of determination (R2; 0.81–0.97) for eight glucosinolates and higher ratio of prediction determination (RPD; 2.42–5.35) for seven glucosinolates in B. juncea populations. Furthermore, range error ratio (RER > 4) for twelve and RER > 10 for eight glucosinolates make the combined model acceptable for screening and quality control. The model also provided excellent prediction for aliphatic glucosinolates in four oilseed Brassica species. Overall, our work highlights the potential of Vis-NIR spectroscopy in estimating glucosinolate content in the economically important Brassica oilseeds.
Defense versus growth trade-offs: insights from glucosinolates and their catabolites
(John Wiley & Sons, 2023) Malhotra, Bhanu; Kumar, Pawan; Bisht, Naveen C.
Specialized metabolites are a structurally diverse group of naturally occurring compounds that facilitate plant-environment interactions. Their synthesis and maintenance in plants is overall a resource-demanding process that occurs at the expense of growth and reproduction and typically incurs several costs. Evidence emerging on different specialized compounds suggests that they serve multiple auxiliary functions to influence and moderate primary metabolism in plants. These new functionalities enable them to mediate trade-offs from defenses to growth and also to offset their production and maintenance costs in plants. Recent research on glucosinolates (GSLs), which are specialized metabolites of Brassicales, demonstrates their emerging multifunctionalities to fine-tune plant growth and development under variable environments. Herein, we present findings from the septennium on individual GSLs and their catabolites (GHPs) per se, that work as mobile signals within plants to mediate precise regulations of their primary physiological functions. Both GSLs and GHPs calibrate growth-defense trade-off interactions either synergistically or directly when they function as storage compounds, abiotic stress alleviators, and one-to-one regulators of growth pathways in plants. We finally summarize the overall lessons learned from GSLs and GHPs as a model and raise the most pressing questions to address the molecular-genetic intricacies of specialized metabolite-based trade-offs in plants.
Editorial: Glucosinolates: Regulation of biosynthesis and hydrolysis
(Frontiers Media S.A., 2020) Malhotra, Bhanu; Bisht, Naveen C.
The members of the Brassicaceae family possess a class of sulfur and nitrogen containing specialized metabolites glucosinolates (GSLs), that are important for plant defense and animal nutrition. Glucosinolates are both constitutive and inducible, and their accumulation is controlled by environmental, molecular, and genetic levels. Much of the information about the glucosinolate biosynthesis, transport, hydrolysis, turnover, crosstalk amongst biosynthesis and hormonal pathways, and mechanisms controlling glucosinolate accumulation and metabolism during abiotic and biotic stresses has been derived from the model plant Arabidopsis thaliana (Figure 1). However, there are still lacunae in fully understanding these regulatory processes in crop species. Thus, the purpose of this Research Topic is to decipher several aspects under the glucosinolate regulatory mechanisms, in view of which a total of eight research articles have been published.
A guide to culturing, maintenance, and leaf inoculation methods for rapid screening and quantification of sclerotinia sclerotiorum infection in mustard
(Springer Nature Publishing AG, 2026) Malhotra, Bhanu; Tiwari, Ruchi; Varghese, Mohan; Bisht, Naveen C.
Sclerotinia rot poses a significant challenge to the cultivation of oilseed Brassica crops, causing the reduction of seed number, weight, and quality leading to >95% yield losses globally. Due to its substantial economic impact on agriculture, Sclerotinia sclerotiorum has been extensively studied at the molecular level and has now been adopted as a model to investigate the host-pathogen interactions. Despite various procedures and strategies described in different reports, there exists a considerable disparity in how the pathogen is cultured, maintained, and manipulated across studies.This chapter provides a comprehensive guide to the fundamental procedures of working with S. sclerotiorum. It describes step-by-step methods for its routine culturing and maintenance over artificial media, replenishing and storing laboratory stocks, and conducting detached leaf assays-a robust method used for screening the mustard cultivars. Additionally, we outline the quantification of pathogen load in planta through qRT-PCR analysis. The methods presented in the current chapter are reproducible and can be suitably applied when working with different isolates of the pathogen.Through the present compilation, we aim to address the research gaps in methods involving the pathogen that would not only benefit the new researchers entering the field but also future research endeavors on white mold.