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In the last six decades, the consumption of reactive nitrogen (Nr) in the form of fertilizer in India has been growing rapidly, whilst the nitrogen use efficiency (NUE) of cropping systems has been decreasing. These trends have led to increasing environmental losses of Nr, threatening the quality of air, soils, and fresh waters, and thereby endangering climate-stability, ecosystems, and human-health. Since it has been suggested that the fertilizer consumption of India may double by 2050, there is an urgent need for scientific research to support better nitrogen management in Indian agriculture. In order to share knowledge and to develop a joint vision, experts from the UK and India came together for a conference and workshop on “Challenges and Opportunities for Agricultural Nitrogen Science in India.” The meeting concluded with three core messages: (1) Soil stewardship is essential and legumes need to be planted in rotation with cereals to increase nitrogen fixation in areas of limited Nr availability. Synthetic symbioses and plastidic nitrogen fixation are possibly disruptive technologies, but their potential and implications must be considered. (2) Genetic diversity of crops and new technologies need to be shared and exploited to reduce N losses and support productive, sustainable agriculture livelihoods. (3) The use of leaf color sensing shows great potential to reduce nitrogen fertilizer use (by 10–15%). This, together with the usage of urease inhibitors in neem-coated urea, and better management of manure, urine, and crop residues, could result in a 20–25% improvement in NUE of India by 2030.

Exitrons are exonic introns. This subclass of intron retention alternative splicing does not contain a Pre-Terminating stop Codon. Therefore, when retained, they are always a part of a protein. Intron retention is a frequent phenomenon predominantly found in plants, which results in either the degradation of the transcripts or can serve as a stable intermediate to be processed upon induction by specific signals or the cell status. Interestingly, exitrons have coding ability and may confer additional attributes to the proteins that retain them. Therefore, exitron-containing and exitron-spliced isoforms will be a driving force for creating protein diversity in the proteome of an organism. This review establishes a basic understanding of exitron, discussing its genesis, key features, identification methods and functions. We also try to depict its other potential roles. The present review also aims to provide a fundamental background to those who found such exitronic sequences in their gene(s) and to speculate the future course of studies. [ABSTRACT FROM AUTHOR]

Main conclusion: The high affinity nitrate transport system is a potential target for improving nitrogen use efficiency of bread wheat growing either under optimal or limiting nitrate concentration. Nitrate uptake is one of the most important traits to take into account to improve nitrogen use efficiency in wheat (Triticum aestivum L.). In this study, we aimed to gain an insight into the regulation of NO3− -uptake and translocation systems in two contrasting wheat genotypes [K9107(K9) vs. Choti Lerma (CL)]. Different conditions, such as NO3−-uptake rates, soil-types, N-free solid external media, and external NO3− levels at the seedling stage, were considered. We also studied the contribution of homeolog expression of five genes encoding two nitrate transporters in the root tissue, along with their overall transcript expression levels relative to specific external nitrate availability. We observed that K9107 had a higher 15N influx than Choti Lerma under both limiting as well as optimum external N conditions in vermiculite-perlite (i.e., N-free solid) medium, with the improved translocation efficiency in Choti Lerma. However, in different soil types, different levels of 15N-enrichment in both the genotypes were found. Our results also demonstrated that the partitioning of dry matter in root and shoot was different under these growing conditions. Moreover, K9107 showed significantly higher relative expression of TaNRT2.1 at the lowest and TaNPF6.1 and TaNPF6.2 at the highest external nitrate concentrations. We also observed genotype-specific and nitrate starvation-dependent homeolog expression bias in all five nitrate transporter genes. Our data suggest that K9107 had a higher NO3− influx capacity, involving different nitrate transporters, than Choti Lerma at the seedling stage. [ABSTRACT FROM AUTHOR]

Fertilization with suitable amendment in acidic soil is crucial to achieve long-term high crop yield without deteriorating soil health in intensive cropping system. We studied the chemical and biological properties of soil, soybean, and wheat yield after 47 years of long-term fertilization in an acidic Alfisol. Treatments were: unfertilized (control); recommended N dose (N); recommended N and P (NP); recommended N, P and K (NPK); NPK + hand weeding (NPK + HW); NPK + 10 Mg ha−1 farmyard manure (NPK + FYM) and NPK + 0.40 Mg ha−1 lime (NPK + lime). Long-term application of NPK + FYM significantly enhanced the soil cation exchange capacity (CEC), organic carbon, available NPK and microbial functions compared to NPK. Application of NPK + lime increased soil pH, dehydrogenase activity (DHA) and bacterial population by 15.7%, 38.8% and 145% respectively, over NPK. Continuous inorganic-P fertilizer application leads to substantial build-up of available-P in soil. Fertilization of FYM/lime with NPK recorded higher crops yield compared to NPK. Soil DHA, bacterial population and CEC were most influencing factors governing grain yield. Overall, long-term application of NPK with FYM/lime improved soil health and crop yield, but rate of inorganic-P input should be curtailed in an Alfisol. [ABSTRACT FROM AUTHOR]

Polyploidization plays an important role in the genesis of cultivated wheat (hexaploid and tetraploid) from its diploid progenitors. Thus, evolution during polyploidization resulted in present-day hexaploid bread wheat. GS2 and Fd-GOGAT enzymes are core components involved in the assimilation of primary nitrogen (N) in plants. In the present study, we aimed to analyze these two important genes at their molecular level to find the extent of variation that occurred during evolution from the ancient diploid progenitors to the modern-day hexaploid bread wheat. Furthermore, we studied their gene expression pattern and assayed both the enzymes under N stress. We also investigated the degree of resilience among these species in terms of certain important morphophysiological and biochemical parameters under N stress. Comparison of the genomic sequences along with their promoter region revealed that both GS2 and Fd-GOGAT genes were located on chromosome 2 and were comprised of 13 and 33 exons respectively. A limited sequence divergence at cDNA and amino acid levels was observed among the genome species, but the divergence was significantly higher in the promoter region. Both these genes were present in three copies in the bread wheat, two copies in the durum wheat, and a single copy in their diploid progenitors. Differential gene expression among the five genome species under N stress suggested major differences in gene regulation due to the difference in cis-elements. Enzyme activity did not correlate with the gene expression level probably due to post-transcriptional and post-translational modification of the enzymes. There was neither correlation between the GS2 and Fd-GOGAT activity in any species. All growth parameters, except root length, decreased or remain unchanged with different degrees of plasticity in the genotypes under N stress and correlated with reduced Fd-GOGAT activity, which supply the primary assimilate glutamate. GS2/Fd-GOGAT enzyme activity along with total N accumulation, protein, chlorophyll, and carotenoid content in shoot were found responsive to the N stress through combined PCA analysis. Our study confirmed the conserved nature of GS2 and Fd-GOGAT enzymes at the CDS and protein level; however, their expression and subsequent effects were different in cultivated wheat and their progenitors. [ABSTRACT FROM AUTHOR]

Polyphenols and tannins have implications for health and nutrition because of their antioxidant activities. Foods with high content of phenolics, such as fruits, vegetables, grains and legumes, show decreasing incidence of several diseases upon their consumption. However, there are limited reports on antioxidative properties of tannins present in legumes. Faba bean seed has been known for high content of condensed tannin which is attributed as one of the antinutritional factors in this highly proteinaceous pulse crop. Therefore, the objective of this study was to estimate and characterize the phenolic compounds in different tissues of this underutilized pulse and their antioxidative activities. Fairly good amount of phenolics were observed in all tissues extract which was quite evident from their high FRAP (Ferric reducing antioxidant power) value. It was further, observed that the extract prepared from its seeds presented a potent radical scavenger activity as indicated by its high capacity to reduce the free radical diphenylpicrylhydrazyl, whereas the tannin-free extract indicated loss of antioxidative activities. The seed extract also interacted with superoxide anions, hydroxyl radicals as well as the oxidant species, hydrogen peroxide. Thus, our results provide evidence that the extract prepared from different tissues of faba bean shows antioxidant and radical scavenging activities largely because of its condensed tannins (proanthocyanidins). [ABSTRACT FROM AUTHOR]

Aim: The objective was to study the growth performance of the broiler birds after feeding Okara meal containing with or without non-starch polysaccharides degrading enzyme. Materials and Methods: 220 day-old broiler chicks were individually weighed and divided randomly into five treatment groups (T, T, T, T and T ) consisting of 44 chicks each which was further subdivided into four replicates of 11 chicks. The 1 2 3 4 5 feed consumption in each replicates of five groups was recorded daily for a total period of 6 weeks experimental feeding. Results: The average total feed consumption of six weeks was 3948.10±7.60, 4088.76±8.30, 4415.33±9.44, 4381.24±9.25 and 4728.76±10.05 (g) in groups T, T, T, T and T, respectively. The differences were statistically non-significant (P>0.05) 1 2 3 4 5 among the various groups. The average total body weight gain and average daily weight gain in birds of group T were 4 significantly higher (P<0.01) than birds of other groups except T group. It showed that 25 percent replacement of ground nut 3 cake with Okara meal and addition of non-starch polysaccharides degrading enzyme (provizyme-bro) had positive effect on growth performance of birds. The increase in weight in broilers of enzyme added group T in comparison to their counterpart 4 without enzyme group (T and T ) attributed to degradation of non-starch polysaccharides in ration, thereby, enhancing the 2 3 utilization of other nutrients. Conclusion: The findings indicated that 25 percent replacement of ground nut cake with Okara meal and addition of nonstarch polysaccharides degrading enzyme had positive effect on growth performance of birds. So, Okara meal feeding had no adverse effect on growth performance of the broilers. [ABSTRACT FROM AUTHOR]

Summary Developing early maturing lentil has the potential to minimize yield losses, mainly during terminal drought. Whole‐genome resequencing (WGRS) based QTL‐seq identified the loci governing earliness in lentil. The genetic analysis for maturity duration provided a good fit to 3:1 segregation (F2), indicating earliness as a recessive trait. WGRS of Globe Mutant (late parent), late‐flowering, and early‐flowering bulks (from RILs) has generated 1124.57, 1052.24 million raw and clean reads, respectively. The QTL‐Seq identified three QTLs (LcqDTF3.1, LcqDTF3.2, and LcqDTF3.3) on chromosome 3 having 246244 SNPs and 15577 insertions/deletions (InDels) and 13 flowering pathway genes. Of these, 11 exhibited sequence variations between bulks and validation (qPCR) revealed a significant difference in the expression of nine candidate genes (LcGA20oxG, LcFRI, LcLFY, LcSPL13a, Lcu.2RBY.3g060720, Lcu.2RBY.3g062540, Lcu.2RBY.3g062760, LcELF3a, and LcEMF1). Interestingly, the LcELF3a gene showed significantly higher expression in late‐flowering genotype and exhibited substantial involvement in promoting lateness. Subsequently, an InDel marker (I‐SP‐383.9; LcELF3a gene) developed from LcqDTF3.2 QTL region showed 82.35% PVE (phenotypic variation explained) for earliness. The cloning, sequencing, and comparative analysis of the LcELF3a gene from both parents revealed 23 SNPs and InDels. Interestingly, a 52 bp deletion was recorded in the LcELF3a gene of L4775, predicted to cause premature termination of protein synthesis after 4 missense amino acids beyond the 351st amino acid due to the frameshift during translation. The identified InDel marker holds significant potential for breeding early maturing lentil varieties. [ABSTRACT FROM AUTHOR]

The nitrogen use efficiency (NUE) of crop plants is limited and enhancing it in rice, a major cereal crop, would be beneficial for farmers and the environment alike. Here we report the genome-wide transcriptome analysis of two rice genotypes, IR 64 (IR64) and Nagina 22 (N22) under optimal (N+) and chronic starvation (N−) of nitrogen (N) from 15-day-old root and shoot tissues. The two genotypes were found to be contrasting in their response to N−; IR64 root architecture and root dry weight remained almost equivalent to that under N+ conditions, while N22 showed high foraging ability but a substantial reduction in biomass under N−. Similarly, the photosynthetic pigments showed a drastic reduction in N22 under low N, while IR64 was more resilient. Nitrate reductase showed significantly low specific activity under N− in both genotypes. Glutamate synthase (GOGAT) and citrate synthase CS activity were highly reduced in N22 but not in IR64. Transcriptome analysis of these genotypes revealed nearly double the number of genes to be differentially expressed (DEGs) in roots (1016) compared to shoots (571). The response of the two genotypes to N starvation was distinctly different reflecting their morphological/biochemical response with just two and eight common DEGs in the root and shoot tissues. There were a total of 385 nitrogen-responsive DEGs (106 in shoots and 279 in roots) between the two genotypes. Fifty-two of the 89 DEGs identified as specific to N22 root tissues were also found to be differentially expressed between the two genotypes under N−. Most of these DEGs belonged to starch and chloroplast metabolism, followed by membrane and signaling proteins. Physical mapping of DEGs revealed 95 DEGs in roots and 76 in shoots to be present in quantitative trait loci (QTL) known for NUE. [ABSTRACT FROM AUTHOR]