A high-throughput method for isolation of salicylic acid metabolic mutants

Background  

Salicylic acid (SA) is a key defense signal molecule against biotrophic pathogens in plants. Quantification of SA levels in plants is critical for dissecting the SA-mediated immune response. Although HPLC and GC/MS are routinely used to determine SA concentrations, they are expensive and time-consuming. We recently described a rapid method for a bacterial biosensor Acinetobacter sp. ADPWH_lux-based SA quantification, which enables high-throughput analysis. In this study we describe an improved method for fast sample preparation, and present a high-throughput strategy for isolation of SA metabolic mutants.     

Genetic diversity for mineral accumulation in the foliage of Chenopodium spp.

Chenopodium spp. is being used as a leafy vegetable and subsidiary grain crop in different parts of the world due to its rich nutritional quality and its ability to grow in stress conditions. A field experiment was conducted in Lucknow (India) to assess the genetic diversity in 40 accessions of Chenopodium spp. based on mineral composition of the leaves. Principal Component Analysis (PCA) showed that the first 4 PCs (Principal Component) accounted for 74.70% of the total variance among the accessions. The first PC (PC1) accounted for 41.96% of the total qualitative variation and had nickel, zinc and chromium with high positive and copper with high negative coefficients. The most important loadings for PC2 were calcium and potassium. Cluster analysis grouped the accessions into 4 major clusters. The first cluster, which showed maximum diversity, had 17 accessions, all of C. quinoa having high content of most of the heavy metals viz. zinc, chromium, nickel and cadmium. Cluster II was the largest consisting of 18 accessions which had low content of nickel, cadmium and chromium. Cluster III contained 3 accessions that had lowest amount of calcium, iron, magnesium and zinc, while accessions in cluster IV were characterized by high levels of calcium, sodium, magnesium, nickel, chromium and cadmium. Significant genotypic differences existed in the heavy metal uptake by plants. Mineral uptake and concentration in Chenopodium spp. corresponds to the taxonomic categorization in the genus and could also be utilized as a supplementary taxonomic tool for grouping together of closely related taxa. Conclusively the diversity can be exploited in plant breeding programs for increasing nutritional value and for bioremediation purposes.     

Acaricide resistance in Rhipicephalus microplus collected from selected districts of Madhya Pradesh,Uttar Pradesh and Punjab states of India

Tropical Animal Health and Production - The isolates of Rhipicephalus microplus collected from Madhya Pradesh (MP), Punjab (PJB) and Uttar Pradesh (UP) states of India were characterized using...     

Hepatic endogenous defense potential of propolis after mercury intoxication

Exposure to mercuric chloride (HgCl₂; 5 mg kg^?1 body weight; i.p.) induced oxidative stress in mice and substantially increased lipid peroxidation (LPO) and oxidized glutathione (GSSG) levels, decreased the level of reduced glutathione (GSH) and various antioxidant enzymes in liver and also increased the activities of liver marker enzymes in serum. Therapy with propolis extract, a resinous wax‐like beehive product (200 mg kg^?1 orally, after mercury administration), for 3 days inhibited LPO and the formation of GSSG and increased the level of GSH in the liver. Release of serum transaminases, alkaline phosphatase, lactate dehydrogenase and γ‐glutamyl transpeptidase were significantly restored after propolis treatment. The activities of antioxidant enzymes, that is, superoxide dismutase, catalase, glutathione‐S‐transferase and glucose‐6‐phosphate dehydrogenase, were also concomitantly restored towards normal levels after propolis administration. These observations clearly demonstrate that propolis treatment augments antioxidant defense against mercury‐induced toxicity and provide evidence that propolis has therapeutic potential as a hepatoprotective agent.     

Differences between Cajanus cajan (L.) Millspaugh and C. cajanifolius (Haines) van der Maesen, the progenitor species of pigeonpea

A study was undertaken to know the difference/diversity between pigeonpea and its closely related wild species C. cajanifolius by studying their morphology, crossability, cytology of the hybrid between the two, and molecular studies. Studies revealed that there are at least 5–6 traits that separate the two species such as flower morphology, pod color and morphology, pod constriction, seed color and strophiole, 100 seed weight that separate C. cajan from C. cajanifolius. Molecular studies revealed that a genetic dissimilarity index value ranging from 0.81 to 0.94 exists between the two species.     

Influence of dietary phosphorus on mineralization and morphology of Indian major carp,catla (<Emphasis Type="Italic">Catla catla</Emphasis>) fingerlings

The present study was conducted to investigate the changes in mineralization and morphology in response to graded levels of dietary phosphorus in Indian major carp, Catla (Catla catla) fingerlings (av. wt. 4.23 ± 0.87 g). The experimental system constituted of 24 150-L capacity plastic tanks (eight treatments, three replicates) stocked with 20 fingerlings each. Eight isonitrogenous and isocaloric semi-purified diets (crude protein 35%, crude lipid 8.5%) were formulated with graded levels of phosphorus (0%-control; 0.1; 0.3; 0.5; 0.7; 0.9; 1.1; 1.3; 1.5%) using KH₂PO₄. The fish were fed twice daily with the respective feeds for a period of 120 days. The percentage of ash content in whole body, vertebrae and opercular bones was found to be significantly (P < 0.05) lower in fish fed low levels of dietary phosphorus (T₁, T₂) in comparison with other treatments. The concentration of phosphorus and calcium was found to be significantly (P < 0.05) lower in whole body, vertebrae and opercula of fish fed low phosphorus diets (T₁, T₂) relative to treatments with higher levels of dietary phosphorus supplementation. The concentration of magnesium in opercular and vertebral tissues of T₁ group was significantly (P < 0.05) lower than all other groups. The X-ray radiographs did not reveal any skeletal deformities in any of the treatments. Truss analysis showed absence of significant morphological variations between fish of different treatments. The deficiency of dietary phosphorus in catla led to significantly lower mineralization of whole body and bone tissues, but the deficiency was not severe enough to cause skeletal deformities and morphological changes in the fish.     

Biological parameters of the endangered fish Chitala chitala (Osteoglossiformes: Notopteridae) from some Indian rivers

Age, growth and maturity data of the freshwater feather back Chitala chitala (Hamilton-Buchanan, 1822) were collected from ten different geographical locations. Out of ten populations, maximum 6+ ages were recorded from four river basins namely river Bhagirathi, Koshi, Saryu and Ganga and the back calculated lengths at 6+ ages ranged from 1033.36–1073.63 mm. In rest of the locations, however, only 3+ age classes were recorded. Specific rate of linear growth (C_l) and specific rate of weight increase (C_w) showed decreases except in two locations. The specific rate of linear growth (C_l) and the specific rate of weight increase (C_w) increased at 3+ age class in the river Bhagirathi. Among other growth parameters, three distinct life stages of C. chitala were observed based on analysis of growth constant data. Analysis of variance (ANOVA) of the back-calculated length data of 10 populations indicated a significant difference (p < 0.05). Out of ten populations studied, six showed significant variation of growth in 1+ age class and two showed significant variation in 2+ to 6+ age classes. Length-weight relationship of the species from all the population was calculated and the coefficient of correlation (r) was at the significant level where the value of ‘b’ was almost 3 for all the locations studied. Male C. chitala attained maturity earlier (2+ age) whereas females matured at age 3+. The percentages of mature individuals also varied between river basins. Based on this study strategies can be proposed for sustainable exploitation of the species from wild populations.     

Targeted species substitution in giant freshwater prawn trade revealed by genotyping

This study presents the molecular barcoding results of giant freshwater prawns and allied products collected from inland landing centres, markets and stores of Vembanad Lake (Kerala state, India) which is recognized as a natural abode for Macrobrachium rosenbergii. Prawns collected from landing centres of the lake could be easily identified as the above with their large size and morphological characters. There were certain ‘alien’ prawns and prawn products (headless shell on, peeled and deveined) traded in the markets and stores of this region as M. rosenbergii. Genotyping of all these samples using COI and 16S rRNA gene sequences confirmed the speciation of individuals from inland landing centres as M. rosenbergii, ‘alien’ prawns and certain prawn products as M. malcolmsonii. To ensure the same and to detect the presence of any other congeners of genus Macrobrachium inhabiting Vembanad Lake, additional homologous COI and 16S rRNA sequences available in NCBI were acquired and incorporated for molecular analyses. Results generated from NJ tree and genetic distance data confirmed the trade of non‐indigenous Macrobrachium species M. malcolmsonii in Kerala for the first time and its use as a species substituent for M. rosenbergii.