D. K. Chauhan

Current Trends of Engineered Nanoparticles (ENPs) in Sustainable Agriculture: An Overview

Nanotechnology is an interesting area of multifaceted research in agricultural perspective. This technology incorporates the manufacturing of material at nano level. Nanoparticles (NPs) have now become an integral part of research because of their unique features like their size, shape and surface reactivity. In agriculture sector engineered nanoparticles (ENPs) i.e., metal NPs, metal oxide NPs and Carbon Nano Tubes (CNTs) etc has been used in the form of nanofertilizers and nanopesticide/ herbicides. Therefore, the appropriate use of nanoparticles could provide a proficient sustainable platform to achieve the food requirement of global massive population. As of the application of nanotechnology to agriculture and food industry is outturn in enhanced crop yield with better food quality as well as safety. Inspite of the significances of nano-material, negative outcomes should also be taken in consideration before applying it on a large scale.

Chromium (VI)-induced phytotoxicity in river catchment agriculture: evidence from physiological, biochemical and anatomical alterations in Cucumis sativus (L.) used as model species

ABSTRACT The present study investigates the impact of different Cr(VI) (50–200 µM) treatments on Cucumis sativus L. seedlings which is worldwide grown in river catchments. Chromium (VI) treatments showed significant (P < .05) reduction in growth, photosynthetic pigments, total protein content and PSII performance, which was in concurrence with a significant (P < .05) increase in the accumulation of Cr(VI) (up to 587 ± 18.19 µg Cr g−1 in roots), lipid peroxidation (MDA: up to 483%), H2O2 (up to 453%) and (up to 551%) compared to the control seedlings. Chlorophyll fluorescence parameters, such as Fm, Fv, Fv/Fm, Fm/F0 and Fv/F0, were declined while F0 showed enhancements (P < .05). Energy flux parameters, such as Phi_E0, Psi_0, PIABS, declined; however, ABC/RC, ET0/RC, DI0/RC and TR0/RC increased significantly (P < .05) under Cr(VI) treatments as compared to control. In addition, the levels of qP were reduced while NPQ was appreciably enhanced under different Cr(VI) treatments. The histochemical observations of H2O2 and were in accordance with their total estimation. Furthermore, Cr(VI) also severely injured the anatomical structure of roots. This study suggests that a higher accumulation of Cr(VI) in cucumber seedlings warrants serious attention in the studied catchments of the Ganges river to avoid any food contamination and biomagnifications to higher trophic levels.

Micronutrients and their diverse role in agricultural crops: advances and future prospective

In plant sciences, the prodigious significance of micronutrient is unavoidable since plant relies primarily on micronutrient as it has profound influence on array of plant activities. Although micronutrients are abundantly present in the soil but plants usually acquire them in relatively trace amounts; hence, regarded as tracer element. B, Cu, Fe, Mn, Zn are such micronutrients required in minute amounts by plants but inexorably play an eminent role in plant growth and development. Plant metabolism, nutrient regulation, reproductive growth, chlorophyll synthesis, production of carbohydrates, fruit and seed development, etc., are such effective functions performed by micronutrients. These tracer elements when present at adequate level, elevate the healthy growth in plant physiological, biochemical and metabolic characteristics while their deficiency promotes abnormal growth in plants. Prevalence of micronutrient deficiency has become more common in recent years and the rate of their reduction has further been increased by the perpetual demands of modern crop cultivars, high soil erosion, etc. On the basis of present existing condition, it is not difficult to conclude that, the regular increment of micronutrient deficiency will be mostly responsible for the remarkable degradation in substantiality of agricultural crops somewhere in near future and so that this issue has now been the subject of intensified research among the breeder, ingenuities and expertise of science. These micronutrients can also be proven toxic when present at accelerated concentrations and such toxicity level endangers the plant growth. Taking this into consideration, the current review unfolds the phenomenal participation of micronutrients in plant sciences and gives a brief overview of the current understanding of main features concerning several micronutrient acquisitions in agricultural crop plants.

Assessment of Antioxidant Potential of Plants in Response to Heavy Metals

Heavy metals (HMs) are consequential environmental contaminant, and their prodigious bioaccumulation in the surroundings has become an enigma for all living organisms including plants. Heavy metal has the potential to react with various indispensable cellular components like DNA, protein, and enzymes and in turn induce several stress responses in plants like oxidative stress which is the root cause for the progression of cell death in the plant. Stress responses inflicted by oxidative stress include severe morphological, metabolic, and physiological amendments in plants like DNA strand breakage, defragmentation of proteins, and damage of photosynthetic pigment, which may stimulate cell death. In reaction, plants have a range of mechanisms to minimize the heavy metal toxicity. Plants are endowed with antioxidant defense mechanism, which can be divided into two groups such as enzymatic antioxidants and nonenzymatic antioxidants, for instance, SOD, CAT, APX, GPX, GR and AsA, GSH, carotenoids, alkaloids, tocopherols, proline, and phenolic compounds, respectively, that together act as the scavengers for free radicals to mitigate the damaging impacts of heavy metal agglomeration in the cells. These antioxidant potentials could be assessed by different in vivo and in vitro methods such as hydrogen atom transfer and electron transfer through which we can evaluate the ROS detrimental action of antioxidant enzymes. Therefore, the present chapter attempts to provide the contemporary knowledge regarding the metal-influenced antioxidant status in plants and also provides the precise pathway that should follow for the future research in the area of antioxidant potentials.