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Globodera rostochiensis (Woll.) and Globodera pallida (Stone), two potato cyst nematodes (PCNs), are significant pests worldwide. The first PCNs from North Himalayan regions of India were detected in 2010 in Shimla, Himachal Pradesh (HP). Despite a domestic quarantine, succeeding surveys in the mountainous regions of North India have shown the presence of PCNs in numerous districts of HP, Jammu and Kashmir and Uttarakhand. The seed plot technique is utilized in North Himalayan regions of India to create virus-free seed and the state agricultural departments distribute it to farmers in other parts of the nation. Therefore, the entire nation should be concerned about the emergence of such a significant potato seed location as the primary sites for large PCN populations. Inorganic pesticide based nematode management is an effectual way to address this biotic stress but improper use of chemicals can have a negative impact on the environment. Therefore, the farming community must prefer the employment of potential biocontrol agents, this might aid in fending off regulatory and environmental pressure. Plant growth-promoting rhizobacteria (PGPR) enabled control of PCNs can be environmentally benign. In light of this, we undertook an extensive and thorough review of the available literature pertaining to PGPRs. Our analysis uncovered that PGPRs can greatly assist in enhancing plant resilience to various stressors that can impede their growth and yield. However, achieving these benefits will require successful development and commercialization efforts. Furthermore, before PGPRs can be widely employed, it is crucial to tackle the challenges related to their selectivity and restricted range of activity. [ABSTRACT FROM AUTHOR]

Cucumber (Cucumis sativus L.) is a popular warm season vegetable used for salads and grown throughout the world under tropical and subtropical conditions. The use of synthetic fertilizers for cucumber production over an extended time period can improve the productivity but consecutively deteriorates soil health. Therefore, with the hypothesis that for an extensive evaluation of different nutrient sources, its influence on the soil health and economics of a crop needs to be quantified critically; a comprehensive study was carried out on cucumber cv. K-75 in a randomized block design with three replications during kharif seasons of 2018 and 2019. The experiment comprised nine treatments of different nutrient sources including organic manures alone and in conjugation with the inorganic fertilizers. Application of RDF + FYM @ 100 q ha−1 (T2) produced 50.22% higher yield over control i.e. T1 and registered the highest available soil NPK content (303.5, 122.3, and 407.9 kg ha−1, respectively) as well as B:C ratio (4.0). From the present investigation, it can be concluded that RDF + FYM @ 100 q ha−1 can be recommended to farmers for maintaining soil fertility and obtaining higher yields. It could be a cost-effective nutrient management module on a sustainable basis. [ABSTRACT FROM AUTHOR]

The present study was carried out on onion cv. Nasik Red in a randomized block design with three replications. The experiment comprised of nine treatments of different nutrient sources including organic manures and inorganic fertilizers. The effects of organic manures (farmyard manure, vermicompost and jeevamrut) alone and in conjugation with inorganic fertilizers on growth, nutrient uptake and yield of onion were studied. Integrated use of inorganic fertilizers and organic manure significantly influenced plant growth, yield and nutrient uptake by crop. The results showed that highest number (7.4) and length of leaves (36.6 cm), bulb size (19 cm2), NPK uptake (122.5, 16.7 and 67.4 kg ha−1, respectively) and biological yield (441.9 q ha−1) was recorded under T2 i.e., RDF + FYM @ 250 q ha−1. Increment in biological yield under T2 was 69.2% over control. Our results could provide a better understanding of the importance of inorganic fertilizers plus organic manure in maintaining soil fertility and thus enhancing nutrient uptake and crop production. [ABSTRACT FROM AUTHOR]

Among abiotic stresses, salt stress adversely affects growth and development in rice. Contrasting salt tolerant (CSR27), and salt sensitive (MI48) rice varieties provided information on an array of genes that may contribute for salt tolerance of rice. Earlier studies on transcriptome and proteome profiling led to the identification of salt stress-induced serine hydroxymethyltransferase-3 (SHMT3) gene. In the present study, the SHMT3 gene was isolated from salt-tolerant (CSR27) rice. OsSHMT3 exhibited salinity-stress induced accentuated and differential expression levels in different tissues of rice. OsSHMT3 was overexpressed in Escherichia coli and assayed for enzymatic activity and modeling protein structure. Further, Arabidopsis transgenic plants overexpressing OsSHMT3 exhibited tolerance toward salt stress. Comparative analyses of OsSHMT3 vis a vis wild type by ionomic, transcriptomic, and metabolic profiling, protein expression and analysis of various traits revealed a pivotal role of OsSHMT3 in conferring tolerance toward salt stress. The gene can further be used in developing gene-based markers for salt stress to be employed in marker assisted breeding programs. HIGHLIGHTS: - The study provides information on mechanistic details of serine hydroxymethyl transferase gene for its salt tolerance in rice. [ABSTRACT FROM AUTHOR]

Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. [ABSTRACT FROM AUTHOR]

Aphids, a hemipteran group of insects pose a serious threat to many of the major crop species including Brassica oilseeds. Transgenic strategies for developing aphid-resistant plant types necessitate phloem-bound expression of the insecticidal genes. A few known phloem-specific promoters, in spite of tissue-specific activity fail to confer high level gene-expression. Here, we identified seven orthologues of phloem-specific promoters in B. juncea (Indian mustard), and experimentally validated their strength of expression in phloem exudates. Significant cis-motifs, globally occurring in phloem-specific promoters showed variable distribution frequencies in these putative phloem-specific promoters of B. juncea. In RT-qPCR based gene-expression study promoter of Glutamine synthetase 3A (GS3A) showed multifold higher activity compared to others, across the different growth stages of B. juncea plants. A statistical method employing four softwares was devised for rapidly analysing stability of the promoter-activities across the plant developmental stages. Different statistical softwares ranked these B. juncea promoters differently in terms of their stability in promoter-activity. Nevertheless, the consensus in output empirically suggested consistency in promoter-activity of the six B. juncea phloem- specific promoters including GS3A. The study identified suitable endogenous promoters for high level and consistent gene-expression in B. juncea phloem exudate. The study also demonstrated a rapid method of assessing species-specific strength and stability in expression of the endogenous promoters. [ABSTRACT FROM AUTHOR]

The productivity of Brassica oilseeds is severely affected by its major pest: aphids. Unavailability of resistance source within the crossable germplasms has stalled the breeding efforts to derive aphid resistant cultivars. In this study, jasmonate-mediated host defense in Indian mustard Brassica juncea (L.) Czern. was evaluated and compared with regard to its elicitation in response to mustard aphid Lipaphis erysimi (Kalt.) and the defense elicitor methyl jasmonate (MeJ). Identification of jasmonate-induced unigenes in B. juncea revealed that most are orthologous to aphid-responsive genes, identified in taxonomically diverse plant-aphid interactions. The unigenes largely represented genes related to signal transduction, response to biotic and abiotic stimuli and homeostasis of reactive oxygen species (ROS), in addition to genes related to cellular and metabolic processes involved in cell organization, biogenesis, and development. Gene expression studies revealed induction of the key jasmonate biosynthetic genes ( LOX, AOC, 12- OPDR), redox genes ( CAT3 and GST6), and other downstream defense genes ( PAL, ELI3, MYR, and TPI) by several folds, both in response to MeJ and plant-wounding. However, interestingly aphid infestation even after 24 h did not elicit any activation of these genes. In contrast, when the jasmonate-mediated host defense was elicited by exogenous application of MeJ the treated B. juncea plants showed a strong antibiosis effect on the infesting aphids and reduced the growth of aphid populations. The level of redox enzymes CAT, APX, and SOD, involved in ROS homeostasis in defense signaling, and several defense enzymes viz. POD, PPO, and PAL, remained high in treated plants. We conclude that in B. juncea, the jasmonate activated endogenous-defense, which is not effectively activated in response to mustard aphids, has the potential to reduce population growth of mustard aphids. [ABSTRACT FROM AUTHOR]

The study presents the impact of drought stress on five finger millet varieties (PR202, VL146, VL315, PES400 and VR708), representing contrasting areas of Indian sub-continent. Drought stress induced increase in the activity of superoxide dismutase, ascorbate peroxidase and glutathione reductase was higher in PR202 and VL315, while the activity was lower in the varieties PES400 and VR708. Ascorbate peroxidase : superoxide dismutase ratio, which is a crucial factor in alleviating drought stress, was higher in varieties PR202 and VL315, whilst the varieties PES400 and VR708 exhibited a lower ratio under stress. The variety PES400 recorded maximum stress induced damage, as indicated by higher accumulation of malondialdehyde and hydrogen peroxide; whereas the variety PR202 recorded least stress induced cytotoxic damage. The results clearly indicate that better drought tolerance of the variety PR202 is positively related to the capacity of its antioxidant system to scavenge reactive oxygen species, resulting in a reduced incidence of oxidative damage. Ascorbate peroxidase : superoxide dismutase ratio is found to be a critical factor governing the stress tolerance potential of different varieties. Therefore, varieties PR202 and VL315 were found to be tolerant while PES400 was susceptible to drought stress. [ABSTRACT FROM AUTHOR]

Plant growth and development and interactions with the environment are regulated by phytohormones and other signaling molecules. During their evolution, plants have developed strategies for efficient signal perception and for the activation of signal transduction cascades to maintain proper growth and development, in particular under adverse environmental conditions. Abscisic acid (ABA) is one of the phytohormones known to regulate plant developmental events and tolerance to environmental stresses. The role of ABA is mediated by both its accumulated level, which is regulated by its biosynthesis and catabolism, and signaling, all of which are influenced by complex regulatory mechanisms. Under stress conditions, plants employ enzymatic and non-enzymatic antioxidant strategies to scavenge excess reactive oxygen species (ROS) and mitigate the negative effects of oxidative stress. Glutathione (GSH) is one of the main antioxidant molecules playing a critical role in plant survival under stress conditions through the detoxification of excess ROS, maintaining cellular redox homeostasis and regulating protein functions. GSH has recently emerged as an important signaling molecule regulating ABA signal transduction and associated developmental events, and response to stressors. This review highlights the current knowledge on the interplay between ABA and GSH in regulating seed dormancy, germination, stomatal closure and tolerance to drought. [ABSTRACT FROM AUTHOR]