A CRISPR way for accelerating cereal crop improvement: Progress and challenges

Humans rely heavily on cereal grains as a key source of nutrients, hence regular improvement of cereal crops is essential for ensuring food security. The current food crisis at the global level is due to the rising population and harsh climatic conditions which prompts scientists to develop smart resilient cereal crops to attain food security. Cereal crop improvement in the past generally depended on imprecise methods like random mutagenesis and conventional genetic recombination which results in high off targeting risks. In this context, we have witnessed the application of targeted mutagenesis using versatile CRISPR-Cas systems for cereal crop improvement in sustainable agriculture. Accelerated crop improvement using molecular breeding methods based on CRISPR-Cas genome editing (GE) is an unprecedented tool for plant biotechnology and agriculture. The last decade has shown the fidelity, accuracy, low levels of off-target effects, and the high efficacy of CRISPR technology to induce targeted mutagenesis for the improvement of cereal crops such as wheat, rice, maize, barley, and millets. Since the genomic databases of these cereal crops are available, several modifications using GE technologies have been performed to attain desirable results. This review provides a brief overview of GE technologies and includes an elaborate account of the mechanisms and applications of CRISPR-Cas editing systems to induce targeted mutagenesis in cereal crops for improving the desired traits. Further, we describe recent developments in CRISPR-Cas–based targeted mutagenesis through base editing and prime editing to develop resilient cereal crop plants, possibly providing new dimensions in the field of cereal crop genome editing

Plant Microbiome: An Ocean of Possibilities for Improving Disease Resistance in Plants

Plant diseases pose a serious threat to crop production and the agricultural economy across the globe. Currently, chemical pesticides are frequently employed to combat these infections, which cause environmental toxicity and the emergence of resistant pathogens. Moreover, the genetic manipulation of plant defense pathways and the breeding of resistant genes has attained limited success due to the rapid evolution of pathogen virulence and resistance, together with host range expansion. Additionally, due to climate change and global warming, the occurrence of multiple stresses during disease outbreak has further impacted overall crop growth and productivity, posing a serious threat to food security. In this regard, harnessing the plant beneficial microbiome and its products can provide novel avenues for disease resistance in addition to boosting agricultural output, soil fertility and environmental sustainability. In plant–beneficial microbiome interactions, induced systemic resistance (ISR) has emerged as a key mechanism by which a beneficial microbiome primes the entire plant system for better defense against a wide range of phytopathogens and pests. In this review, we provide the recent developments on the role of plant beneficial microbiomes in disease resistance. We also highlight knowledge gaps and discuss how the plant immune system distinguishes pathogens and beneficial microbiota. Furthermore, we provide an overview on how immune signature hormones, such as salicylic acid (SA), jasmonic acid (JA) and ethylene (ET), shape plant beneficial microbiome. We also discuss the importance of various high-throughput tools and their integration with synthetic biology to design tailored microbial communities for disease resistance. Finally, we conclude by highlighting important themes that need future attention in order to fill the knowledge gaps regarding the plant immune system and plant-beneficial-microbiome-mediated disease resistance

Exploring the Potential of Multiomics and Other Integrative Approaches for Improving Waterlogging Tolerance in Plants

Soil flooding has emerged as a serious threat to modern agriculture due to the rapid global warming and climate change, resulting in catastrophic crop damage and yield losses. The most detrimental effects of waterlogging in plants are hypoxia, decreased nutrient uptake, photosynthesis inhibition, energy crisis, and microbiome alterations, all of which result in plant death. Although significant advancement has been made in mitigating waterlogging stress, it remains largely enigmatic how plants perceive flood signals and translate them for their adaptive responses at a molecular level. With the advent of multiomics, there has been significant progress in understanding and decoding the intricacy of how plants respond to different stressors which have paved the way towards the development of climate-resistant smart crops. In this review, we have provided the overview of the effect of waterlogging in plants, signaling (calcium, reactive oxygen species, nitric oxide, hormones), and adaptive responses. Secondly, we discussed an insight into past, present, and future prospects of waterlogging tolerance focusing on conventional breeding, transgenic, multiomics, and gene-editing approaches. In addition, we have also highlighted the importance of panomics for developing waterlogging-tolerant cultivars. Furthermore, we have discussed the role of high-throughput phenotyping in the screening of complex waterlogging-tolerant traits. Finally, we addressed the current challenges and future perspectives of waterlogging signal perception and transduction in plants, which warrants future investigation

<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-GB">Variability in the accessions from Aravali range assessed for domestication of the Cleomaceae biodiesel plant <i style="mso-bidi-font-style:normal">Cleome viscosa</i> Linn.</span>

246-255<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-GB">In an earlier study at our laboratory showed that the biodiesel derived from the seed oil of the annual herbaceous medicinal weed plant Cleome viscosa Linn. possesses properties similar to the commercial biodiesel produced from Jatropha seed oil. Here, the possibilities of domestication of C. viscosa were examined. With this objective, 15 accessions from Aravali range in North-West India and two from North-East India were evaluated for phenotypic and genetic variability. The accessions were cultivated in four seasons from May to November 2009 at New Delhi by growing them in randomized block design replicated four times. The accessions were studied for 6 qualitative and 13 agronomic characters and significant genetic variability in all the agronomic traits was observed. On the basis of morphological features, the accessions fell into two groups: a small leaved group and a large leaved group. While the small leaved group comprised of accessions from Rajasthan, the large leaved group included accessions from different locations in North-west and North-East India. One of the small leaved accessions called CVR14 was identified as a putative high yielding accession. The July-October (or monsoon-autumn) season of about 13-15 weeks was observed to be the most suitable period for obtaining rainfed crop of <i style="mso-bidi-font-style: normal">C. viscosa CVR14. The DNA fingerprinting based analysis of hierarchical relationships between accessions demonstrated that large leaved and small leaved accessions were inter-related. The results indicated that C. viscosa accessions from diverse locations perhaps comprised a single complex.</span

Plant beneficial microbiome a boon for improving multiple stress tolerance in plants

Beneficial microbes or their products have been key drivers for improving adaptive and growth features in plants under biotic and abiotic stress conditions. However, the majority of these studies so far have been utilized against individual stressors. In comparison to individual stressors, the combination of many environmental stresses that plants experience has a greater detrimental effect on them and poses a threat to their existence. Therefore, there is a need to explore the beneficial microbiota against combined stressors or multiple stressors, as this will offer new possibilities for improving plant growth and multiple adaptive traits. However, recognition of the multifaceted core beneficial microbiota from plant microbiome under stress combinations will require a thorough understanding of the functional and mechanistic facets of plant microbiome interactions under different environmental conditions in addition to agronomic management practices. Also, the development of tailored beneficial multiple stress tolerant microbiota in sustainable agriculture necessitates new model systems and prioritizes agricultural microbiome research. In this review, we provided an update on the effect of combined stressors on plants and their microbiome structure. Next, we discussed the role of beneficial microbes in plant growth promotion and stress adaptation. We also discussed how plant-beneficial microbes can be utilized for mitigating multiple stresses in plants. Finally, we have highlighted some key points that warrant future investigation for exploring plant microbiome interactions under multiple stressors

Exogenously Applied Sulphur Improves Growth, Photosynthetic Efficiency, Enzymatic Activities, Mineral Nutrient Contents, Yield and Quality of <i>Brassica juncea</i> L.

Background: Due to increasing domestic and industrial demand, edible oil production is not keeping up with demand. To fill this gap, the productivity of oilseeds can be increased by applying adequate nutrients, particularly sulphur (S), at the crucial growth stage. Purpose: The present study aims to explore the best concentration of S for its foliar application on various cultivars of mustard. Methods: A factorial randomized pot experiment was conducted to investigate the role of leaf-applied S on growth, physiobiochemistry, yield and quality traits of three cultivars of Brassica juncea L. (mustard). Five levels of S viz. 0 (water), 15, 30, 45 and 60 ppm S constituted one variant, and the three cultivars (Chutki, Nath Sona and Rohini) were the other variants. The various levels of S were sprayed at 50 and 70 days after sowing (DAS). The growth and physio-biochemical characteristics were studied at 90 DAS, and yield and quality attributes at 120 DAS (harvest). Results: The data indicated that increasing S levels up to 45 ppm S improved all parameters of mustard and thereafter (at the level above 45 ppm S) decreased. Cultivar Nath Sona, followed by Rohini and Chutki, performed best. Among the foliar spray treatment of different levels of S, the application of 45 ppm S increased plant dry weight by 40.21, 35.65 and 30.96%, photosynthetic rate by 28.27, 27.44 and 36.29%, pods of a plant by 15.23, 12.12 and 10.80%, seed yield of a plant by 7.54, 3.89 and 4.91%, oil content by 48.70, 46.31 and 43.15% and oil yield of a plant by 24.56, 23.93 and 22.35% in cultivar Nath Sona, Rohini and Chutki, respectively, compared with their respective water-treated plants. Moreover, the oil was examined by GC-MS technique for its various components. The analysis revealed that there were 36 compounds in the oil of the non-treated plants and 44 compounds in the oil of plants treated with 45 ppm S. The extra compounds resulted from the application of 45 ppm S. Conclusion: It may be concluded that two sprays of 45 ppm S proved effective in improving the growth, physio-biochemical characteristics, yield and quality of cultivars of mustard, particularly Nath Sona

Exogenously Applied Sulphur Improves Growth, Photosynthetic Efficiency, Enzymatic Activities, Mineral Nutrient Contents, Yield and Quality of Brassica juncea L.

Background: Due to increasing domestic and industrial demand, edible oil production is not keeping up with demand. To fill this gap, the productivity of oilseeds can be increased by applying adequate nutrients, particularly sulphur (S), at the crucial growth stage. Purpose: The present study aims to explore the best concentration of S for its foliar application on various cultivars of mustard. Methods: A factorial randomized pot experiment was conducted to investigate the role of leaf-applied S on growth, physiobiochemistry, yield and quality traits of three cultivars of Brassica juncea L. (mustard). Five levels of S viz. 0 (water), 15, 30, 45 and 60 ppm S constituted one variant, and the three cultivars (Chutki, Nath Sona and Rohini) were the other variants. The various levels of S were sprayed at 50 and 70 days after sowing (DAS). The growth and physio-biochemical characteristics were studied at 90 DAS, and yield and quality attributes at 120 DAS (harvest). Results: The data indicated that increasing S levels up to 45 ppm S improved all parameters of mustard and thereafter (at the level above 45 ppm S) decreased. Cultivar Nath Sona, followed by Rohini and Chutki, performed best. Among the foliar spray treatment of different levels of S, the application of 45 ppm S increased plant dry weight by 40.21, 35.65 and 30.96%, photosynthetic rate by 28.27, 27.44 and 36.29%, pods of a plant by 15.23, 12.12 and 10.80%, seed yield of a plant by 7.54, 3.89 and 4.91%, oil content by 48.70, 46.31 and 43.15% and oil yield of a plant by 24.56, 23.93 and 22.35% in cultivar Nath Sona, Rohini and Chutki, respectively, compared with their respective water-treated plants. Moreover, the oil was examined by GC-MS technique for its various components. The analysis revealed that there were 36 compounds in the oil of the non-treated plants and 44 compounds in the oil of plants treated with 45 ppm S. The extra compounds resulted from the application of 45 ppm S. Conclusion: It may be concluded that two sprays of 45 ppm S proved effective in improving the growth, physio-biochemical characteristics, yield and quality of cultivars of mustard, particularly Nath Sona

Thiamin stimulates growth, yield quality and key biochemical processes of cauliflower (Brassica oleracea L. var. Botrytis) under arid conditions.

Thiamin is a crucial vitamin with a vast variety of anti-oxidative and physiological roles in plants subjected to abiotic stresses. We examined the efficiency of foliar-applied thiamin (50 and 100 mM) on growth, yield quality and key-biochemical characteristics of two cultivars (FD1 and FD3) of cauliflower (Brassica oleracea L.) under water-deficit stress. Water stress at the rate of 50% field capacity (F.C.) markedly decreased the plant biomass, leaf total phenolics and ascorbic acid (AsA) contents. In contrast, drought-induced increase was noted in the leaf [hydrogen peroxide (H2O2), AsA, proline, malondialdehyde (MDA), glycinebetaine (GB), total soluble proteins and oxidative defense system in terms of high activities of peroxidase (POD), and catalase (CAT) enzymes] and the inflorescence (total phenolics, proline, GB, MDA, H2O2, and activities of SOD and CAT enzymes) characteristics of cauliflower. However, foliar-applied thiamin significantly improved growth and physio-biochemical attributes except leaf and inflorescence MDA and H2O2 contents of both cauliflower cultivars under water stress. Overall, application of thiamin enhanced the plant growth may be associated with suppressed reactive oxygen species (ROS) and upregulated antioxidants defense system of cauliflower

Identification and comparative analysis of Brassica juncea pathogenesis-related genes in response to hormonal, biotic and abiotic stresses.

Not AvailablePathogenesis-related proteins (PRs) are the antimicrobial proteins which are commonly used as signatures of defense signaling pathways and systemic acquired resistance. However, in Brassica juncea most of the PR proteins have not been fully characterized and remains largely enigmatic. In this study, full-length cDNA sequences of SA (PR1, PR2, PR5) and JA (PR3, PR12 and PR13) marker genes were isolated from B. juncea and were named as BjPR proteins. BjPR proteins showed maximum identity with known PR proteins of Brassica species. Further, expression profiling of BjPR genes were investigated after hormonal, biotic and abiotic stresses. Pre-treatment with SA and JA stimulators downregulates each other signature genes suggesting an antagonistic relationship between SA and JA in B. juncea. After abscisic acid (ABA) treatment, SA signatures were downregulated while as JA signature genes were upregulated. During Erysiphe cruciferarum infection, SAand JA-dependent BjPR genes showed distinct expression pattern both locally and systemically, thus suggesting the activation of SA- and JA-dependent signaling pathways.Not Availabl