Research

L - An SEM image (using secondary electrons) of a cryo-fractured seedling root of Arachis hypogaea at 15 mm from the root apex.             

R - Enhancing phytoremediation through biotechnological innovations.                         

Why plants are important?

Cyanobacteria and plants can convert water and carbon dioxide into oxygen and organic carbon thus are precursors for supporting heterotrophic and aerobic life forms on earth. Photoautotrophs such as cyanobacteria, algae, and plants contributed to the evolution of heterotrophic life in the marine environment and its transition to the terrestrial environment. These organisms “terraformed” earth by modifying its atmosphere and surface that can support the existence of human life.

Why we study vascular plants?

A large part of oxygen and organic carbon are synthesized by land plants; thus, they are of extreme importance to humans. The significance of land plants in human society is evident from the earliest human civilizations to the most recent scientific endeavors. The cave paintings, relics of ancient civilizations, emergence of agriculture, tradition and cultural practices across globe and the use of scientific knowledge such as genetics and biotechnology to study and improve plant traits clearly indicates the importance of plants for humans. However, most of the focus has been on the above-ground parts of plants and unfortunately very little attention has been paid towards the below-ground plant parts such as roots. Research in plant science reflects this skewed distribution, however, with the availability of new technologies, research concerning plant roots are increasing.

Why root biology can be the key to paradigm shift in agriculture and food security?

Besides anchorage, water and nutrient sequestration, roots are associated with several plant-microbe interactions. Some of the well-documented interactions involve microbes such as Agrobacterium, Rhizobium and mycorrhizal fungi. Such interactions, improve plant and soil health while providing a network for communication between distant plants. Roots can sense water and nutrient distribution and reprogram their post-embryonic development to access such resources thus manifesting plasticity of root architecture. The quiescent centre in roots offers an excellent model for stem cell studies while their close interaction with microbes offers immense potential for antimicrobial discovery. Finally, roots being a sink for photosynthates are a major source for carbohydrates and can act as a sink for atmospheric carbon thus holds promise for food security and mitigating climate change.

Current or proposed projects

Ⅰ. Agriculture

Due to unsustainable agricultural practices, salt and drought stress have become a major challenge in agriculture. Such challenges remain and will exacerbate with rise in global population, climate change and shift in demography towards urban settlements. Several cellular and physiological parameters of plants such as water potential, ion homeostasis, photosynthetic efficiency and transpiration rate are adversely affected by stress resulting in lower productivity. Several field studies indicated the role of potassium and calcium in ameliorating plant stress. However, the cellular and molecular mechanism through which the ions can mitigate stress and their limitations are yet to be identified. Pertinent questions such as role nutrient interactions, transporters, channels, genetic regulatory networks, ion homeostasis, compatible solutes and reactive oxygen species can help us better understand the process. 

Ⅱ. Environment

Anthropogenic activities have led to heavy metal contamination of several habitats with severe health and environmental costs. Phytoremediation has been used as an ecofriendly, sustainable and inexpensive strategy to clean environment of heavy metal pollution. Though the technique has become popular in the past two decades yet the molecular mechanism of heavy metal accumulation in plant tissue is not clearly understood. The distribution and compartmentation mechanism of the metals along with their effect on the nutrient content of edible parts of plants are pertinent questions. Understanding the physiological, biochemical and genetic mechanisms that allow plants to tolerate heavy metal toxicity can propel biotechnological innovations for climate smart agriculture and sustainable environment.

Ⅲ. Space

Space exploration has incentivized the concept of growing plants in Moon and Mars for sustainable human settlement. Several essential nutrients for plant growth have been detected in mars and moon, however their relative ratio and concentration are different as compared to soil on earth. Recent, reports on the growth of Arabidopsis on lunar soil and space-grown lettuce have encouraged the possibility of growing plants using such matrix and conditions. Growing plants hydroponically in simulated solutions that reflect the nutrient status of Mars and Moon would be the first step in identifying their effect in plant morphology, physiology and productivity. Such initial data would be essential to design strategy for nutrient management and genetic modification of plants for “space farming”.

Ⅳ. Health

Antibiotics enters the food chain through plants grown in contaminated soil and water. The use of manure from antibiotic fed cattle, waste water and urban agriculture has exacerbated the problem and antibiotic contamination in food is a major health concern. Thus, to improve food safety it is important to understand the uptake mechanism, distribution and fate of antibiotics in plant tissues. Their effects in altering the nutrient status and physiology of plant cell is equally important to investigate their effect on productivity. Hydroponically grown plants can be treated with fluorescent antibiotics to investigate their uptake and distribution while MALDI-TOF MS can be utilized to ascertain their fate in plant tissues. Metabolic inhibitors such as ATPase inhibitor, transpiration inhibitor, aquaporin inhibitor and channel blockers can be used to estimate their effects on cell physiology.

Ⅴ. Cell signaling

a.  Several developmental events in the life cycle of plants such as seed development, seed germination, vegetative growth, stem elongation, leaf expansion, flowering and pollen maturation are regulated by gibberellins. DELLA proteins besides being involved in crosstalk between phytohormones and the environment are also involved in repression of gibberellin responses thus are considered as master growth repressors. Gibberellins mediates the polyubiquitination and degradation of DELLA proteins. DELLA genes have been exclusively identified in land plants and they had a significant role in green revolution which mostly focused on modifying above-ground parts of plants. However, knowledge gap exists about their role in root development though we know that nodulation and the growth of endodermis are influenced by such protein. Thus, transcript analysis of DELLA gene expression has potential for biotechnological innovation in developing better root architecture and climate-smart agriculture.

b. Calcium signaling through CBL-CIPK network plays a major role in plant’s response to developmental and environmental cues. CBL–CIPK signaling pathway is involved in several biological processes including nutrient sequestration, abiotic/biotic stress response and stomatal movement. The pathway maintains Ca2+ homeostasis in plants through several membrane-bound channels and transporters that tightly regulates sequestration and release of calcium from intracellular organelles and environment. Thus, functional characterization of the CBL–CIPK pathway can be a precursor for biotechnological innovation to develop resilient crops.