Purification and properties of indole 2,3-dioxygenase from maize leaves

An indole 2,3-dioxygenase was purified ca 38-fold from maize leaves. The enzyme had an MW of about 98000, an optimum pH of 5.0 and the energy of activation was 9.1 kcal/mol. The K_max for indole was 1.4 × 10^?4 M. The enzyme was inhibited by diethyldithiocarbamate, salicylaldoxime and sodium dithionite. The inhibition by diethyldithiocarbamate was specifically reversed by Cu²⁺. The dialysed enzyme was stimulated by Cu²⁺. Four atoms of oxygen were utilized in the disappearance of 1 mole of indole. Inhibition of the enzyme by -SH compounds and -SH group inhibitors, and their partial removal by Cu²⁺ only, suggested the involvement of -SH groups in binding of Cu²⁺ at the catalytic site.     

Adaptation of beta-ray gauge technique for measurement of water deficit of intact rice leaves

A linear relationship was obtained between the logarithm of count rate and absorber’s (Aluminum foil and leaf) effective thickness in the range of 4.25 to 18.00 mg cm^?2. Also relative water content (RWC) and absorber effective thickness was linearly related (Y = ?89.80 + + 15.84 X, and r = 0.99). From these relationships it was possible to determine the RWC of a rice leaf simply by measuring the radiation intensity of fresh, fully turgid and completely dry leaf by beta ray gauge technique without the added necessity of determining the mass of the leaf.     

Factors affecting in vitro clonal propagation of Prosopis cineraria

Genotype, age of tree, nature of explant and size (length and diameter), season of explant collection, explant position on medium, plant growth regulators and certain additives (ascorbic and citric acids, adenine sulphate, L-arginine, glutamine and ammonium citrate), incubation conditions, and subculturing period greatly influenced the in vitro clonal propagation of P. cineraria. The maximum number of 10–12 shoots were induced from the nodal shoot segment from pruned thorny adult trees on Murashige and Skoog's (MS) medium containing 0.1 mgl^-1 indole- 3-acetic acid (IAA)+2.5 mgl^-1 benzylaminopurine (BAP)+additives. Higher temperature (31+-2°C) and mixed (fluorescent and incandescent) light of 50 mol m^-2 s^-1 photon flux density for 12 h per day photoperiod favoured shoot induction and subsequent growth. Explants from thornless trees produced 6–8 shoots per explant on MS medium containing 0.1 mgl^-1 IAA+5.0 mgl^-1 BAP + additives. Nodal shoot segments obtained from root and stump sprouts produced multiple shoots. Root segments differentiated into multiple shoots on MS medium containing 0.5 mgl^-1 indolebutyric acid (IBA)+2.5 mgl^-1 BAP.Differentiated shoots multiplied best on MS medium containing 0.1 mgl^-1 naphthalene acetic acid (NAA)+1.0 mgl^-1 BAP + additives. To yield multiple shoots the original explant was transferred 6 times on fresh medium after harvesting the differentiated shoots. Shoots were rooted by pulsing with 100 mgl^-1 IBA for 4 h and then culturing on hormone-free half strength MS medium. Initial dark incubation for 5 days at high temperature (33±2°C) was found essential for root induction from shoots which was 63% within two weeks. The rooted plantlets contained a consistent number of chromosomes (2n=28). It is suggested that the protocol developed could be useful for cloning of mature and tested trees of P. cineraria.     

Quantification and correlation of vesicular-arbuscular mycorrhizal propagules with soil properties of some mollisols of northern India

The populations of vesicular-arbuscular mycorrhizae (VAM) propagules by the most probable number method in some mollisols and their correlations with some important soil properties were determined. On average, the six soils, Phoolbagh clay loam, Beni silty clay loam, Haldi loam, Nagla loam, Khamia sandy loam and Patherchatta sandy loam contained 4.9, 4.0, 7.9, 7.9, 3.3 and 13.0 propagules/g soil, respectively, i.e. none of the soils was found to be high in VAM. The size of the VAM population was compared to soil properties such as pH, organic carbon, sand content, available phosphorus and available potassium, cation-exchange capacity, silt and clay contents. A significant positive correlation (r=0.586) was only found with available soil phosphorus (P<0.05) and a significant negative correlation (r=-0.555) with soil clay content (P<0.05).Directorate research paper series No. 7862     

Effect of soil moisture stress on legume-rhizobium symbiosis in soybeans

Summary In a pot culture experiment, the influence of soil moisture stress at different physiological stages of soybean, cv. Hark, on nodulation, symbiosis and nitrogen accumulation was studied. Moisture stress reduced leghemoglobin content of root nodules and nitrogen uptake by plants. It had no effect on number of bacteroids. Stress at mid bloom and rapid pod filling stages reduced yield and seed protein content. However, these parameters were not affected by stress at nodule initiation and early flowering stages, though, flower initiation and maturity of the plant were delayed. Moisture stress at any stage did not alter nitrogen status of roots.     

Effect of dimethyl sulfoxide (DMSO) on zinc availability (L-value), growth and metabolic activities of rice plants

Summary Effects of soil application (0.01, 0.1 and 1%) and foliar sprays (0.001, 0.01 and 0.1%) of dimethyl sulfoxide (DMSO) and soil application of Zn (10 and 20 ppm) on growth, yield, photosynthetic pigments and some enzymatic activities of rice (Oryza sativa L. variety Jaya) were investigated in a Zn-deficient soil under pot culture trials. Control plants showed typical Zn deficiency symptoms, very low dry matter and chlorophyll contents and significantly lower activities of carbonic anhydrase and tryptophan synthetase. Application of 10 or 20 ppm Zn to the soil markedly improved plant growth, chlorophyll content, enzymatic activities, Zn availability (L-value), and grain yield. Application of 1% DMSO to the soil proved to be severly phytotoxic for plant growth and dry matter accumulation. Application of lower doses of DMSO to the soil (0.01 and 0.1%) or as foliar sprays (0.001 and 0.01%), however, slightly increased dry weights of all plant parts at 45 days after transplanting. Grain yield was significantly increased by all DMSO treatments, except 1% soil application which completely suppressed the grain formation.Enzymatic activities and chlorophyll and carotenoid accumulation showed concentration-dependent stimulation or inhibition by DMSO treatments. Carbonic anhydrase activity was significantly increased by most of the DMSO treatments whereas tryptophan synthetase activity was stimulated only by the lowest dose of soil (0.01%) and foliar (0.001%) applications. Chlorophyll content was stimulated by lower doses of foliar application of DMSO (0.001 and 0.01%) but the other DMSO treatments brought about a concentration-dependent decrease in chlorophyll accumulation. Carotenoid accumulation was inversely related to that of chlorophylls. Chlorophyll: carotenoid ratio was increased by all DMSO and Zn treatments except 1% soil application of DMSO. Zn availability (L-value) of the soil was increased by all DMSO treatments. Zn content of leaf blades was positively correlated with chlorophyll content (r=0.579), tryptophan synthetase (r=0.700) and carbonic anhydrase (r=0.537) activities but negatively correlated with that of carotenoid content (r=–0.896). The possible mechanisms of DMSO on plants are discussed in relation to its possible agricultural utility.Publication No. 811 under Journal Series of the Experiment Station, G.B. Pant of Agriculture & Technology, Pantnagar (Nainital), India.     

Epigenetic Modulation in Parkinson’s Disease and Potential Treatment Therapies

In the recent past, huge emphasis has been given to the epigenetic alterations of the genes responsible for the cause of neurological disorders. Earlier, the scientists believed somatic changes and modifications in the genetic makeup of DNA to be the main cause of the neurodegenerative diseases. With the increase in understanding of the neural network and associated diseases, it was observed that alterations in the gene expression were not always originated by the change in the genetic sequence. For this reason, extensive research has been conducted to understand the role of epigenetics in the pathophysiology of several neurological disorders including Alzheimer’s disease, Parkinson’s disease and, Huntington’s disease. In a healthy person, the epigenetic modifications play a crucial role in maintaining the homeostasis of a cell by either up-regulating or down-regulating the genes. Therefore, improved understanding of these modifications may provide better insight about the diseases and may serve as potential therapeutic targets for their treatment. The present review describes various epigenetic modifications involved in the pathology of Parkinson’s Disease (PD) backed by multiple researches carried out to study the gene expression regulation related to the epigenetic alterations. Additionally, we will briefly go through the current scenario about the various treatment therapies including small molecules and multiple phytochemicals potent enough to reverse these alterations and the future directions for a better management of PD.

     

Deciphering the Probiotic Potential of Bacillus amyloliquefaciens COFCAU_P1 Isolated from the Intestine of Labeo rohita Through In Vitro and Genetic Assessment

Probiotics and Antimicrobial Proteins - In this study, a bacterial strain COFCAU_P1, isolated from the digestive tract of a freshwater teleost rohu (Labeo rohita), was identified as Bacillus...     

Assessment of yield enhancement in cashew (Anacardium occidentale L.) by the pollinator sharing effect of magnetic bee-friendly plants in India

The objective of this study was to test the hypothesis that pollinator sharing among cashew (Anacardium occidentale L.) and co-blooming magnetic bee-friendly plants facilitate higher productivity of cashew nuts. We examined the reproductive efficacy of cashew in three sites with distinct vegetation pattern (site I: sparsely distributed individuals, without association of co-blooming magnetic bee-friendly plant; site II: densely distributed individuals, without association of co-blooming magnetic bee-friendly plant; site III: densely distributed individuals, associated with co-blooming magnetic bee-friendly plants). Floral traits (including flowering time, flower architecture, number of flowers per panicle, hermaphrodite- male flower ratio, floral rewards, anthesis time and longevity of flower) does not differ among the study sites. According to the value of relative pollinator service (RPS), Apis dorsata was the primary pollinator of cashew and also shared by the co-blooming bee-friendly plants. The abundance of pollinators was the highest in site III and the lowest in site I. The nut yield was also significantly higher in site III cashew orchard which was in association with magnetic bee-friendly plants. Therefore, we can conclude that the association of co-blooming magnetic plants increased nut yield of cashew through the enhancement of pollinator's services.