Improved micropropagation protocol and enhancement in biomass and chlorophyll content in Stevia rebaudiana (Bert.) Bertoni by using high copper levels in the culture medium

Incorporation of a range of higher concentrations of CuSO₄·5H₂O in MS medium [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassay with 240 tobacco tissue cultures. Physiol. Plant 15, 473–497] significantly enhanced direct shoot bud induction and proliferation from cultured leaf and nodal explants taken from mature plants of Stevia rebaudiana. Shoot bud induction medium was supplemented with BAP (2.2 μM) and IAA (2.8 μM). When the concentration of CuSO₄·5H₂O in the induction medium was raised to 0.5 μM (five times the MS level, i.e. 0.1 μM) there was significant increase in percentage response along with increase in shoot bud number per explant. The shoots were healthy, well developed with dark green broader leaves. There was remarkable increase in total biomass and chlorophyll content at increased (0.5 μM) copper level in the medium. During proliferation stage also presence of high copper levels in the medium favoured increase in shoot bud number per explant.     

Variant biochemical responses: intrinsic and adaptive system for ecologically different rice varieties

Journal of Crop Science and Biotechnology - India has a diverse range of agro-ecological conditions which support the cultivation of different rice varieties differing in the adaptation which is so...     

Functional delivery of a cytosolic tRNA into mutant mitochondria of human cells

Many maternally inherited and incurable neuromyopathies are caused by mutations in mitochondrial (mt) transfer RNA (tRNA) genes. Kinetoplastid protozoa, including Leishmania, have evolved specialized systems for importing nucleus-encoded tRNAs into mitochondria. We found that the Leishmania RNA import complex (RIC) could enter human cells by a caveolin-1-dependent pathway, where it induced import of endogenous cytosolic tRNAs, including tRNA(Lys), and restored mitochondrial function in a cybrid harboring a mutant mt tRNA(Lys) (MT-TK) gene. The use of protein complexes to modulate mitochondrial function may help in the management of such genetic disorders.     

In vitro tuberisation of Gloriosa superba L. on basal medium

A suitable protocol for in vitro tuber production using non-dormant tubers of Gloriosa superba L. on Murashige and Skoog (MS) medium without addition of plant growth regulators is reported in the present study. Among the different basal media tested MS medium was found to be suitable for induction and development of secondary tubers; one in vitro tuber per explant was obtained after 6 weeks and 3 tubers per explant after 12 weeks of culture. These tubers produced healthy green shoots that rooted on basal medium. Best rooting was noted in half strength (half organics and inorganics) MS medium with one-fifth nitrates.     

Effect of thidiazuron (TDZ) on in vitro regeneration of blackgram (Vigna mungo L.) embryonic axes

Regeneration has been achieved in blackgram (Vigna mungo) using thidiazuron (TDZ) in the culture medium. The explanted cotyledon with wounded embryonic axes produced the highest number (9.75–10.45) of healthy, elongated shoots when cultured on shoot bud regeneration medium (SRI) composed of 2 μM BAP, 2 μM KIN, 2 μM TDZ, and 0.5 μM NAA followed by multiple shoot regeneration (SRII) medium containing 2 μM BAP, 2 μM KIN, and multiple shoot elongation (SE) medium (0.5 μM of BAP + 0.5 μM of KIN). The presence of TDZ in combination with BAP and NAA in the SRI medium for one sub-culture cycle (10–14 days) significantly increases formation of multiple shoot buds per explant. Independent, healthy shoots obtained were selected for both in vitro rooting and grafting. Establishment of plantlets in the soil was highest (80–100%) in the case of in vitro rooted compared to grafted shoots (40%). The protocol appears to be competent to Agrobacterium-meditated transformation with ‘gus’ as a reporter gene. PCR analysis of the T₀ and T₁ progenies showed the presence and transmission of the transgene. We document here the regeneration and transformation of blackgram using cotyledons with wounded embryonic axes and the protocol appears to be suitable for genetic transformation of blackgram.     

A Laboratory Model for Convection in Earth's Core Driven by a Thermally Heterogeneous Mantle

Thermal convection experiments in a rapidly rotating hemispherical shell suggest a model in which the convection in Earth's liquid outer core is controlled by a thermally heterogeneous mantle. Experiments show that heterogeneous boundary heating induces an eastward flow in the core, which, at a sufficiently large magnitude, develops into a large-scale spiral with a sharp front. The front separates the warm and cold regions in the core and includes a narrow jet flowing from the core-mantle boundary to the inner-core boundary. The existence of this front in the core may explain the Pacific quiet zone in the secular variation of the geomagnetic field and the longitudinally heterogeneous structure of the solid inner core.     

Soil Quality Assessment Through Minimum Data Set Under Different Land Uses of Submontane Punjab

Soil quality degradation is a major challenge in submontane Punjab. This poses a great threat to soil quality of this particular area. Thus, a study was conducted to address the selection of most appropriate soil quality indicators and to know the status of soil quality in the area under different land uses. Principal component analysis (PCA) approach was employed to get the minimum data set. Geo-referred soil samples were collected from five different land uses and analyzed for different physical, chemical, and biological attributes. The PCA was performed which screened out the five principal components (PCs) with eigenvalue >1. Soil quality index was highest under the land use forest (0.80) followed by grasses (0.79), horticulture (0.78), cultivated (0.75), and bare (0.67). The organic carbon contributed maximum to soil quality (28.5%) followed by available K (19.4%), electrical conductivity (18.3%), K-factor of universal soil loss equation (USLE) (14.9%), plant available water (10.5%), and clay (8.3%). Conclusively, the study area falls under the medium category of soil quality.