142 research outputs found
Response of combined abiotic stresses on maize (Zea mays L.) inbred lines and interaction among various stresses
In tropics, maize is largely grown as rain fed crop in marginal areas often faces drought and waterlogging simultaneouslyin same season that critically affects plant growth and development. The aim of the research was to studythe response of combined abiotic stresses and the interaction among various stresses on maize inbred plants. Inthe present study, eighty maize (Zea mays L.) inbred lines were screened, for multiple abiotic stresses at the vegetativestage. All the traits, observed were severely affected, in drought x low-N stress compare to waterloggingx low-N stress. However in both the stress combinations (drought x low-N and waterlogging x low-N) chlorophyllcontent decreases significantly, low-N stress has synergistic effect on the maize plants. Hence the overall effectof stress combination was negative causing enhanced damage to plants. Whereas, interaction of drought x waterloggingstress showed the antagonized each other response that primarily enhanced growth parameters (leafarea, plant height and stem diameter) and it has improved the tolerant mechanism of maize plants. Therefore weconcluded, the response of maize various plants exposed to combinations of stresses is depend on interactionof stresses
Purification and characterization of thermostable chitinase from a novel S. maltophilia strain
Aims: The presents study examines the purification and characterization of a chitinase from S. maltophilia SJ602 strainisolated from a soil sample collected from Jamia Hamdard, New Delhi.Methodology and Results: The purification steps included chitin affinity using colloidal chitin as the affinity matrix andcolumn chromatography using Sephadex G-100. The chitinase was purified to 66 fold having a yield of 17%. The molecular weight of the chitinase was found to be around 29 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The pH and temperature optima of the purified chitinase were found to be at pH 5.5 and60 °C, respectively. Conclusion, Significance and Impact of the study: Besides showing a significant yield, the enzyme has a highthermal stability which has its applicability in the recycling of chitin waste
Perfil lipídico, compuestos volátiles y estabilidad oxidativa durante el almacenamiento del aceite de semilla de Opuntia ficus-indica marroquí
The fatty acids, sterol, tocopherol and volatile compositions of Moroccan cold-pressed cactus (Opuntia ficus-indica) seed oil were studied. The most abundant fatty acid, tocopherol and sterol were linoleic acid (60.6%), γ-tocopherol (533 mg/kg) and β-sitosterol (6075 mg/kg), respectively. In this study, 23 volatile compounds were identified with perceivable odor attributes for 14 compounds. The oxidative quality of cactus seed oil was monitored over 4 weeks at 50 °C. Increases in PV, K232 and FFA were detected during the first two weeks as well as a decrease in the induction time; whereas no change was reported for the K270 values. The amount of total phenolic content increased until it reached 0.3 mg/kg and then decreased by the end of the storage period; while tocopherols started to decrease after the first week. The fat-free residue extracts showed a very strong effect to reduce the oxidation of linoleic acid. Consequently, the extracts were significantly more effective to bleach β-carotene in the β-carotene-linoleic acid assay in comparison with the control.Se estudiaron los ácidos grasos, esteroles, tocoferoles y la composición volátil del aceite de semilla de cactus marroquí (Opuntia ficus-indica) prensado en frío. Los ácidos grasos, tocoferoles y esteroles más abundantes fueron el ácido linoleico (60,6%), γ-tocoferol (533 mg/kg) y β-sitosterol (6075 mg/kg), respectivamente. En este estudio, se identificaron 23 compuestos volátiles con atributos perceptibles para 14 de ellos. La oxidación del aceite de semilla de cactus fue monitoreada durante 4 semanas a 50°C. Se observó un aumento en el PV, K232 y FFA durante las dos primeras semanas y una disminución en el tiempo de inducción, mientras que no se apreciaron cambios para los valores de K270. La cantidad de fenoles totales aumentó hasta alcanzar 0,3 mg/kg y luego disminuyó al final del almacenamiento, mientras que los tocoferoles comenzaron a disminuir después de la primera semana. Los extractos de residuos libres de grasa mostraron un efecto muy fuerte para reducir la oxidación del ácido linoleico. En consecuencia, los extractos fueron significativamente más efectivos para blanquear el β-caroteno en el ensayo de β-caroteno-ácido linoleico en comparación con el control
Compartmentalization of Cells Bearing "Rheumatic” Cell Surface Antigens in Peripheral Blood and Tonsils in Rheumatic Heart Disease
Monoclonal antibodies that recognize "rheumatic” antigens of peripheral blood non-T cells were used to study the compartmentalization of such cells in peripheral blood and tonsils of individuals with rheumatic heart disease (RHD) and suitable control subjects. The peripheral blood of most (71%) of the 42 individuals with RHD contained cells reacting with monoclonal antibody 83S19.23 or 256S.10, whereas these cells were present in only 17% of the 41 control subjects (P < .02). However, none of 21 individuals with RHD had such cells in their tonsils, although they were present in the tonsils of 50% of the 40 control subjects (P < .03). These results may reflect a failure in RHD of organ-specific homing of cells with the epitopes recognized by the antibodies. The presence of these cells in tonsils may be important in the immune response to streptococcal pharyngeal infection, and their absence in RHD may be involved in the unusual immune responses characteristic of this diseas
Host stage preference and parasitism behaviour of Aenasius bambawaleian an encyrtid parasitoid of Phenacoccus solenopsis
In Pakistan, the cotton mealybug, Phenacoccus solenopsis Tinsley (Sternorrhyncha (Homoptera): Pseudococcidae), is a serious pest of many cultivated plants. A parasitoid, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae), is associated with P. solenopsis. In order to mass rear A. bambawalei for a biological control program, it is important to investigate the parasitoid’s host stage preference and its parasitism behavior for P. solenopsis in order to optimize production. The present tudy showed that under both choice and no choice conditions, the parasitoid preferred 3rd instar and pre-reproductive host stage mealybugs for parasitism. Parasitoid larva developing inside the host exhibited a greater longevity, shorter developmental period and longer body size in these preferred host stages. Our study also confirmed that A. bambawalei showed no attraction to male mealybugs and no host feeding on any host stage was recorded. The ability of the parasitoid to effectively discriminate between suitable and non-suitable stages means that it is feasible to rear it on a mixed population
Designing, construction and characterization of genetically encoded FRET-based nanosensor for real time monitoring of lysine flux in living cells
Plant regeneration through somatic embryogenesis from stem and petiole explants of Indian chicory (<i style="">Cichorium intybus</i> L.)
250-255An efficient protocol has been developed for rapid propagation of Indian chicory (Cichorium intybus L.) through somatic embryo development. Indirect somatic embryogenesis was induced through nodal stem and petiole explants, cultured on Murashige and Skoog (MS) medium containing different concentrations of 2,4-D, NAA or IAA. Callus was induced from both the explants after 3 wk of inoculation. Subsequently, calli were sub-cultured on MS medium containing different auxin/cytokinin ratios that influenced the intensity of embryo formation, germination and ability to regenerate plants. Somatic embryogenesis was more intensive in medium with higher concentration of Kn (1.5 mg L-1) and lower concentration of IAA (0.5 mg L-1) supplemented with vitamin-free casein hydrolysate (500 mg L-1). After sub-culture, the embryoids were matured onto a fresh MS medium supplemented with Kn (1.5 mg L-1) + IAA (0.1 mg L-1) + IBA (1.0 mg L-1) + CH (500 mg L-1). The germination of embryos into shoots and less developed roots occurred on the same medium with slight change in IBB concentration (0.5 mg L-1). Further, root formation occurred in MS medium supplemented with 1.0 mg L-1 IBA
Molecular cloning and structural characterization of HMG-CoA reductase gene from <i style="">Catharanthus roseus</i> (L.) G. Donn. cv. Albus
16-22The
3-hydroxy-3-methyl glutaryl-CoA reductase (HMGR) catalyzes the conversion of
HMG-CoA to mevalonate, the first committed step in isoprenoid biosynthesis
pathway in plants. HMG-CoA reductase gene was amplified from the Catharanthus roseus (L.) G. Donn. cv.
Albus by polymerase chain reaction (PCR) with primers designed using published
sequence of HMG-CoA reductase c-DNA of C. roseus cv. Little Delicata (Acc. No. M96068). PS2 SERVER was used to generate three dimensional (3-D) structure of the
enzyme using human HMG-CoA reductase as template. The
structure was evaluated at various web interfaced
servers, i.e., PROCHEK, Profunc and PDBsum, for checking the stereo interfaced
quality of the structure in terms of bonds, bond angles, dihedral angles,
structural as well as functional domains. The generated model was visualized
using the Rasmol. The results of these studies revealed that HMG-CoA reductase
gene from cv. Albus had 99% sequence
homology with hmgr cDNA of cv. Little Delicata. The amino acid sequence of the HMGR protein of cv.
Albus was found closely
related to the members of the family Solanaceae and distantly related to the members
of the families Euphorbiaceae and Brassicaceae. The enzyme has N-terminal
transmembrane domain and a C-terminal catalytic domain with active sites that
can bind to HMG-CoA and NADPH2. The fold of the substrate domain is
unique and resembles the prism with 28-residue helix forming the central core.
The homology model of enzyme generated in the present study, hence, could be
used in determining the mechanistic function of this important class of
proteins
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