Sanjay Kumar Gupta

Dietary zinc promotes immuno-biochemical plasticity and protects fish against multiple stresses

ABSTRACT The abiotic and biotic stress is an episode that effect on regulatory, neuro‐endocrine and immune systems of animals including fish. The stress creates stimulatory and suppressive of immune system resulting in increases the incidence of infection. In view of these points, we have conducted an experiment to mitigate the stress through a nutritional approach through Zinc (Zn) supplementation in Pangasius hypophthalmus (initial weight‐3.65 ± 0.75 g). Three isocaloric and isonitrogenous diets with graded levels of zinc 0, 10 and 20 mg/kg were prepared and fed to seven different groups with each in triplicate. The experimental group as follows as normal water with control diet (Ctr/Ctr), lead (Pb) exposed and fed with control diet (Ctr/Pb), control diet and exposed to Pb and temperature (Ctr/Pb‐T), Zn 10 mg/kg fed without stressors (Zn‐ 10 mg/kg), Zn 20 mg/kg fed without stressors (Zn‐20 mg/kg), Zn 10 mg/kg fed and Pb and temperature exposed (Pb‐T/Zn 10 mg/kg) and Zn 20 mg/kg fed and exposed to Pb and temperature (Pb‐T/Zn 20 mg/kg). The Pb in treated water was maintained at the level of 1/20th of LC50 (4 ppm) and temperature at 34 °C in exposure groups. The neutraceuticals role of dietary Zn was studied in terms of antioxidative enzymes (catalase, superoxide dismutase, glutathione‐S‐transferase), stress markers (Heat shock protein 70, cortisol, acetylcholine esterase, blood glucose, Vitamin C), immunological parameters (Total protein, albumin, globulin, A/G ratio and NBT) and subsequent challenge with Aeromonas veronii biovar sobria. The antioxidative enzymes, stress markers, albumin were significantly (p < 0.01) elevated, brain AChE and immuno‐hematological parameters were significantly (p < 0.01) decreased due to lead (Pb) and temperature exposure. The relative survival (%) was reduced due to the concurrent effect of Pb, high temperature stress and bacterial challenge. Zinc at the rate of 10 and 20 mg/kg was found to be restore the biochemical and immunological parameters against concurrent exposure to lead (Pb), temperature and pathogenic infection. Results obtained in the present study indicate that supplementation of 10 and 20 mg/kg of Zn in the diet has a definitive role in the mitigation of lead (Pb) and temperature exposure along with pathogenic infection in P. hypophthalmus. HighlightsDietary zinc reduce antioxidative enzymes of Pangasius hypophthalmus reared under Pb and high temperature.The different level of dietary zinc protect neurotransmitter enzymes (AChE) of P. hypophthalmus reared under Pb and high temperature.Dietary zinc enhanced Immunomodulation of P. hypophthalmus reared under Pb and high temperature.Dietary zinc enhanced survival of P. hypophthalmus after infection with Aeromonas veronii biovar sobria.

Selenium nanoparticles enhanced thermal tolerance and maintain cellular stress protection of Pangasius hypophthalmus reared under lead and high temperature

There is strong relation between nutrition and thermal tolerance of fish in terms of improved critical temperature minima (CTmin), lethal temperature minima (LTmin), critical temperature maxima (CTmax), and lethal temperature maxima (LTmax). Fishes act as quantifying indicators of the climate change due to their critical thermal limits in nature and ability to adjust thermal sensitivity to maintain their homeostasis. In the present study, biologically synthesised selenium nanoparticles (Se-NPs) from fisheries waste (fish gill) were used to evaluate its efficacy for enhancement of thermal tolerance of Pangasius hypophthalmus reared under lead (Pb) and high temperature (34°C) for 72days. At the end of the experimental period, CTmin, LTmin, and CTmax, LTmax and cellular metabolic stress were evaluated. The CTmin, LTmin were noticeably (p<0.01) reduced and CTmax, LTmax were enhanced in treatment groups fed with dietary Se-NPs. It was also observed that CTmax and LTmax were increased with acclimation temperature. The positive correlation was perceived between CTmin, LTmin (Y=-0.45+11.05x, R2, 0.768) and CTmax, LTmax (Y=-0.78+8.17x, R2, 0.858) fed with Se-NPs supplemented diet and exposed to Pb and high temperature. Significant improvements in the oxidative and metabolic enzymes were noticed post thermal tolerance experiment. Overall results indicated that incorporation of Se-NPs @ 1mg/kg in diet can confer protection against Pb and thermal stress in P. hypophthalmus.

Grain and Food Quality Traits of Some Indigenous Medicinal Rice Cultivars of Manipur, India

Manipur, a northeastern state of India lying in the Indo-Burmese biodiversity hot-spot is endowed with rich biodiversity of rice cultivars including those with medicinal values. The systematic evaluation of the indigenous cultivars for their grain and food qualities has not been carried out yet. Hence 13 indigenous medicinally used cultivars were subjected to grain and food quality studies. The cultivar, Naganap, has found to be of high protein type. Chinachang and Meriunap possessed strong scent comparable to Basmati 370. Most of them are of low and intermediate amylose (<20%) content and have high hulling and milling recoveries with good cooking qualities.

QTLomics in Soybean: A Way Forward for Translational Genomics and Breeding

Food legumes play an important role in attaining both food and nutritional security along with sustainable agricultural production for the well-being of humans globally. The various traits of economic importance in legume crops are complex and quantitative in nature, which are governed by quantitative trait loci (QTLs). Mapping of quantitative traits is a tedious and costly process, however, a large number of QTLs has been mapped in soybean for various traits albeit their utilization in breeding programmes is poorly reported. For their effective use in breeding programme it is imperative to narrow down the confidence interval of QTLs, to identify the underlying genes, and most importantly allelic characterization of these genes for identifying superior variants. In the field of functional genomics, especially in the identification and characterization of gene responsible for quantitative traits, soybean is far ahead from other legume crops. The availability of genic information about quantitative traits is more significant because it is easy and effective to identify homologs than identifying shared syntenic regions in other crop species. In soybean, genes underlying QTLs have been identified and functionally characterized for phosphorous efficiency, flowering and maturity, pod dehiscence, hard-seededness, α-Tocopherol content, soybean cyst nematode, sudden death syndrome, and salt tolerance. Candidate genes have also been identified for many other quantitative traits for which functional validation is required. Using the sequence information of identified genes from soybean, comparative genomic analysis of homologs in other legume crops could discover novel structural variants and useful alleles for functional marker development. The functional markers may be very useful for molecular breeding in soybean and harnessing benefit of translational research from soybean to other leguminous crops. Thus, soybean crop can act as a model crop for translational genomics and breeding of quantitative traits in legume crops. In this review, we summarize current status of identification and characterization of genes underlying QTLs for various quantitative traits in soybean and their significance in translational genomics and breeding of other legume crops.

Genetic parameters of selection and stability and identification of divergent parents for hybridization in rice bean ( Vigna umbellata Thunb. (Ohwi and Ohashi)) in India

Fifty-two genotypes of rice bean (Vigna umbellata Thunb. (Ohwi and Ohashi)), an under-cultivated crop, were evaluated in the rainy (kharif) seasons of 2001, 2002 and 2003 in the North Eastern Hill Region, India to select suitable genotypes for cultivation in the North Eastern Hill region and to identify promising parents for hybridization programmes. The germplasm studied comprised 44 Indian and eight foreign genotypes. A wide range of variability was observed for eight characters studied (plant height, number of branches/plant, stem thickness, pod length, number of seeds/pod, 100-seed weight, pod weight/plant and seed yield/plant). Number of days to mid-flowering and number of days to maturity showed little variation. High heritability (0·58) and high genetic advance (0·53) were observed for 100-seed weight, high heritability (0·93) and moderate genetic advance (0·37) for seed yield/plant, and high heritability (0·60) and low genetic advance (0· 13) for number of days to mid-flowering. Since the main aim in rice bean breeding is to develop high yielding, early maturing genotypes with low plants, selection was based mainly on the mean performance of these three traits over the 3 years, as well as their stability. One of the genotypes, RBL 1, was very high yielding, although the yield was not stable across years. Another genotype, RBS 24, was very early maturing and had very short plants compared with the other genotypes studied. These two, along with several other genotypes selected, may be promising for a hybridization programme aiming to develop dwarf, early maturing genotypes with high yield. The best yielding genotypes, namely RBL 1, RCRB1-3 and IC 187911, may be recommended for cultivation in the shifting cultivation areas (Jhum) regions of North Eastern India.

Immuno-protective role of biologically synthesized dietary selenium nanoparticles against multiple stressors in Pangasinodon hypophthalmus

ABSTRACT An environment friendly and sustainable approach is being emerged in the area of nanotechnology for accelerated growth and development of culturable aquatic animals hence green chemistry is gaining momentum in recent years. The present study has been carried out to delineate the effects of selenium nanoparticles (Se‐NPs) on growth performance, antioxidative status and immunity of fish reared under lead (Pb) and high temperature (34°C). Three hundred and fifteen fish were equally distributed in seven treatments in triplicates. Three isocaloric and isonitrogenous experimental diets viz. control (Se‐NPs‐0 mg/kg), Se‐NPs at 1mg/kg and Se‐NPs at 2mg/kg were formulated. The fish were reared under lead (Pb, 1/21st of LC50 (4ppm)) and high temperature (34°C) stress and fed with or without dietary Se‐NPs. The effects of dietary Se‐NPs were studied in terms of growth performance (Weight gain %, feed conversion ratio, protein efficiency ratio and specific growth rate), antioxidative status (catalase, superoxide dismutase, glutathione‐S‐transferase and glutathione peroxidase), neurotransmitter enzymes (AChE), stress biomarkers (heat shock protein 70, serum cortisol, blood glucose, vitamin C), immunological status (total protein, A/G ratio and respiratory burst activity) in Pangasinodon hypophthalmus post challenge with Aeromonas veronii biovar sobria. Results of the investigation demonstrated significant improvement of growth performance, antioxidative status, neurotransmitter enzyme activity, stress markers and more importantly enhanced immunity of the fish with dietary incorporation of Se‐NPs at 1mg/kg. In addition, post bacterial infection, the relative % survival increased and cumulative mortality % decreased in the group fed with Se‐NPs at 1mg/kg diet. Pb and high temperature treated and fed with control diet group showed devastating impact on the growth performance, antioxidative status, stress markers and immunity of the fish. Similarly, application of Se‐NPs at 2mg/kg showed poor growth performance and elevated level of oxidative stress and other stress biomarkers including other biochemical attributes. Inclusive results indicated that, Se‐NPs at 1mg/kg has capability to enhance overall performance and alleviate multiple stresses in P. hypophthalmus. Hence, Se‐NPs at optimum level have ability to develop green chemistry in feed industry for better growth performance of the fish. HIGHLIGHTSDietary Se‐NPs enhanced growth performance and antioxidative status of Pangasinodon hypophthalmus reared under Pb and high temperature.Dietary Se‐NPs protect neurotransmitter enzymes (AChE) of P. hypophthalmus reared under Pb and high temperature.Dietary Se‐NPs enhanced Immunomodulation of P. hypophthalmus reared under Pb and high temperature.Dietary Se‐NPs enhanced survival of P. hypophthalmus after infection with Aeromonas veronii biovar sobria.

Genetic analyses for deciphering the status and role of photoperiodic and maturity genes in major Indian soybean cultivars

Allelic combinations of major photoperiodic (E1, E3, E4) and maturity (E2) genes have extended the adaptation of quantitative photoperiod sensitive soybean crop from its origin (China ∼35 ∘N latitude) to both north (up to ∼50 ∘N) and south (up to 40 ∘S) latitudes, but their allelic status and role in India (6–35 ∘N) are unknown. Loss of function and hypoactive alleles of these genes are known to confer photoinsensitivity to long days and early maturity. Early maturity has helped to adapt soybean to short growing season of India. We had earlier found that all the Indian cultivars are sensitive to incandescent long day (ILD) and could identify six insensitive accessions through screening 2071 accessions under ILD. Available models for ILD insensitivity suggested that identified insensitive genotypes should be either e3 /e4 or e1 (e1-nl or e1-fs) with either e3 or e4. We found that one of the insensitive accessions (EC 390977) was of e3 /e4 genotype and hybridized it with four ILD sensitive cultivars JS 335, JS 95-60, JS 93-05, NRC 37 and an accession EC 538828. Inheritance studies and marker-based cosegregation analyses confirmed the segregation of E3 and E4 genes and identified JS 93-05 and NRC 37 as E3E3E4E4 and EC 538828 as e3e3E4E4. Further, genotyping through sequencing, derived cleaved amplified polymorphic sequences (dCAPS) and cleaved amplified polymorphic sequences (CAPS) markers identified JS 95-60 with hypoactive e1-as and JS 335 with loss of function e3-fs alleles. Presence of photoperiodic recessive alleles in these two most popular Indian cultivars suggested for their role in conferring early flowering and maturity. This observation could be confirmed in F 2 population derived from the cross JS 95-60 × EC 390977, where individuals with e1-as e1-as and e4e4 genotypes could flower 7 and 2.4 days earlier, respectively. Possibility of identification of new alleles or mechanism for ILD insensitivity and use of photoinsensitivity in Indian conditions have been discussed.

Advances in Soybean Genomics

Soybean is an agronomically important crop that is endowed with rich seed protein and oil. It enriches the soil by fixing nitrogen through symbiosis with bacteria. In addition to human consumption, soybean is a major protein source in animal feeds and is also becoming a major crop for biodiesel production. A major landmark in soybean genomics research was its draft genome sequence assembly (cultivar Williams 82) following whole-genome shot gun (WGS) approach. It revealed 950 Mb (megabases) of assembled and anchored sequence as against the predicted 1,115 Mb genome consequently representing 85 % of the whole genome. Development of comprehensive physical map employing chiefly Bacterial artificial chromosomes (BAC) and Binary large-insert BAC clones (BIBAC) have assisted in the whole genome sequencing venture and in targeted genetic marker development, accelerating positional cloning approaches along with the generation of rapid and robust EST maps. Comprehensive Expressed Sequence Tags (ESTs) repository and genome sequence of the crop have helped in sound integration of physical map with the genetic map. In order to perform genetic and genomic analysis various molecular markers like RFLP, RAPD, AFLP, SSR, SNP etc. have been employed on RIL or F2 populations. In addition the genome is typified with single nucleotide polymorphisms (SNPs) and its utilization in molecular breeding applications like QTL mapping, positional cloning and association mapping studies is gaining impetus. QTLs associated with foremost traits of agronomic interests including QTLs for Aphid resistance, Soybean Cyst Nematode (SCN) resistance among others have been identified and validated. Further molecular marker assisted QTL introgression and gene pyramiding for traits like enhanced seed protein concentration and Soybean Mosaic Virus (SMV) resistance, insect resistance etc. have been accomplished. Legume comparative genomics using orthologous genomic regions have addressed queries relating to Nucleotide binding-Leucine rich repeat (NB-LRRs) genes, polyploidy, and genome evolution. In the soybean functional genomics arena, in addition to the conventional assays involving qRT-PCR, Northern blotting, global gene expression analysis like Serial analysis of gene expression (SAGE), microarrays kind strategies are being widely employed. With the identification of micro RNAs (miRNAs) as ultimate gene effector molecules identification and characterization of novel miRNAs in soybean is gaining a momentum. Thus the rapid development of soybean genomics and transcriptomics has provided tremendous opportunity for the genetic improvement of soybean.

Evaluation of Genotypic Variation and Suitability of Rice Bean Genotypes for Mid-Altitudes of Meghalaya, India

In the North Eastern Hill Region of India, the shifting or jhum cultivation is practiced in 16.79 lac ha area and rice bean is an essential part of jhum. Increasing the productivity of jhum is one of the important management options to uplift the economies of farmers. Identification / development of early maturing, high yielding rice bean genotypes that may give stable yields, is the most important breeding objective in this region. Fifty two rice bean genotypes were evaluated in kharif seasons for three consecutive years to select suitable genotypes for cultivation in this region and identify suitable parents for hybridization programmes. Wide range of variability was observed for the characters studied. Grain yield was found to be positively correlated with all the characters except days to maturity. Two lines, IC 187911 and RCRB 1-3 with high grain yield/plant, average stability and predictable performance over three years, were identified as suitable for cultivation in the region. An analysis of the percentage contribution to genetic diversity revealed that 100-seed weight and pod yield/plant were the major contributing characters towards genetic diversity. Based on the diversity in clusters and their mean performances for various characters, probable parents were identified for developing high yielding and early maturing genotypes.