Effect of different zinc levels on activity of superoxide dismutases & acid phosphatases and organic acid exudation on wheat genotypes

A field study was carried out to investigate the effect of three Zn levels 0, 20 kg ZnSO₄ ha⁻¹ and 20 kg ZnSO₄ ha⁻¹+ foliar spray of 0.5 % ZnSO₄ on superoxide dismutase activity, acid phosphatase activity and grain yield and a pot experiment to study the effect of zinc deficient and sufficient conditions on organic acid exudation. Increasing Zn levels was established as beneficial in improving the enzyme activities of genotypes. Combined foliar and soil application of Zn proved to be superior of all the treatments. Zinc application resulted in a maximum increment limit of 96.8 % in superoxide dismutase activity, 75.76 % in acid phosphatase activity, and a decrement limit of 88.57 % in oxalic acid exudation irrespective of stages and year of study. The increased enzyme activities had a positive impact on grain yield. As an average of all genotypes an improvement of 19.88 % in 2009 and 21.29 % in 2010 due to soil application while of 16.45 % in 2009 and 13.01 % in 2010 due to combined application was calculated for grain yield. There existed a variation among genotypes in showing responses towards zinc application and the genotypes UP 2584 and PBW 550 were found to be more responsive.     

Cloning, in silico characterization and interaction of cysteine protease and cystatin for establishing their role in early blight disease in tomato

Cysteine protease (CP) and Cysteine protease inhibitor (CPI) or cystatin constitute a critical point in programmed cell death (PCD), a basic biological phenomenon which takes place in the plants, when they are exposed to varying biotic and abiotic stresses. In the present study we isolated and cloned cDNAs encoding cysteine protease and cystatin from early blight infected tomato plants. Using computational biology tools the sequence-structure-function relationships for the tomato cystatin and cysteine protease were elucidated. Interaction between the cystatin and cysteine protease of host and pathogen is higher as compared to interaction shown by cystatin and cysteine protease within the host. The interaction energy of (a)tomato cystatin—tomato cysteine protease, (b)tomato cystatin—fungal cysteine protease and (c)tomato cysteine protease—fungal cystatin are ?319.33 Kcal/mol, ?504.71 Kcal/mol and ?373.731 Kcal/mol respectively. Comparative protein sequence analysis with different plant cystatins and cysteine protease were also done with the sequences of cystatin and cysteine protease isolated from tomato. Structures for all the cystatin and cysteine protease were modeled along with their interactions with fungal cystatin and cysteine protease in order to explore the structural variability and its manifestation at the functional level. This helped to relate the already known functions of these proteins with their sequences as well as the predicted structures. This also served to better understand the CP-CPI interaction operational in developing this protein family and its implication in plant defense during fungal pathogenesis in tomato plants.     

C9orf72 deficiency promotes microglial-mediated synaptic loss in aging and amyloid accumulation

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A systemic approach to understand plants’ responses under abiotic stress: a laboratory exercise for undergraduate biology majors

ABSTRACT

This article describes a ten week long laboratory exercise designed for undergraduate students aimed at enhancing their understanding of physiological and biochemical responses of plants under dehydration stress. Hypothesis was built around previous reports which suggested that exogenous application of certain elicitors leads to transient alleviation of dehydration stress in plants. The chosen elicitors were Calcium and Sodium Nitroprusside (Nitric Oxide elicitor) which were tested on Rice plants under dehydration stress. The experiments were divided into four categories: 1. Water Status and Osmotic adjustment: relative water content (RWC) and Proline content 2. Oxidative Damage: Lipid peroxidation of membranes, electrolyte leakage, total peroxide level 3. Metabolic Health: photosynthesis pigments (chl a, b and carotenoids) and 4. Reactive oxygen species (ROS) scavenger enzymes: ascorbate peroxidase (Apx) and catalase (CaT) assays. The instructor along with the teaching assistants acted as a mentor by initially training the students in the required technical skills and then later guiding them through the course of the project. This curriculum embedded research exercise was designed to foster science process skills and develop integrative thinking for solving scientific problems by employing a hands-on approach in a plant physiology laboratory course.     

Molecular Detection and Exploration of Diversity Among Fungal Consortium Involved in Phosphate Solubilization

Abstract

Phosphorous (P) that upholds life become unattainable as most of them become unavailable due to the formation of insoluble complexes with cations such as Ca²⁺, Al³⁺ and Fe³⁺ forming a complex calcium phosphate (Ca₃(PO₄)₂), aluminum phosphate (AlPO) and ferrous phosphate (FePO) that results in the decrease of soluble P to a greater extent. There are several reports stating that several rhizospheric fungal species play an important role in solubilizing these insoluble phosphates into a soluble form by the excretion of enzymes like phosphatase, phytase enzymes, and organic acids. In view of this, so we have collected twenty fungal isolates having probable phosphate solubilizing efficiency from different regions of Lucknow, India. Their morphological and biochemical characteristics were tested. Among all, six efficient fungal isolates were further checked at molecular level by using 18S rRNA universal primers and by RAPD means. A dendrogram indicated 40-90% homology i.e., highest similarity was found in between species of Aspergillus flavus and A. biplanus with 33.8% similarity while minimum similarity was observed among A. flavus and Fusarium oxysporum. These findings suggest RAPD proves as, a reliable molecular tool that helps in strain specific discrimination.