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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]

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]