Coliform pollution mapping in major watersheds along Jhelum River Basin of Kashmir Himalaya.

Coliform pollution for the last three decades in major river systems of the world has resulted in far ranging impacts on water quality. In this context, the present study aimed to assess the levels of indicator bacteria like total Coliform (TC), fecal Coliform (FC) and fecal Streptococcus (FS) in major watersheds of Kashmir valley. Sampling was carried out for a period of 2 years (summer 2017 to spring 2019) along several upstream, midstream and downstream reaches of Jhelum River Basin (JRB), while analysis was carried out by multiple tube fermentation technique involving Most Probable Number (MPN). Major highlights of the results revealed high levels of TC, FC and FS among downstream sites with pronounced seasonal variations between summer and winter. TC was highest at all the reaches and during all the seasons followed by FC and FS. Non-metric multidimensional scaling (NMDS) revealed more variation in Coliform count among reaches as compared to seasons. Mantle test revealed that environmental factors like observable environmental pressure (OEP) (r: 0.235, p < 0.0001), DO (r: 0.2815, p < 0.0001) and temperature (r: 0.04419, p = 0.0104) had prominent effect on Coliform distribution as compared to geographical factors. The study thus highlights the prevalence of Coliform bacteria along JRB resulting from fecal sources. Due to growing urbanization and lack of adequate sewage treatment facilities, there is an increase in the levels of Coliform bacteria along downstream reaches especially those residing within lower Jhelum and Dara watershed, which could jeopardize water quality and public health.

The role of plant-associated rhizobacteria in plant growth, biocontrol and abiotic stress management.

The rhizosphere is the region around the plant roots where maximum microbial activities occur. In the rhizosphere, microorganisms' beneficial and harmful activities affect plant growth and development. The mutualistic rhizospheric bacteria which improve plant growth and health are known as plant growth-promoting rhizobacteria (PGPR). They are very important due to their ability to help the plant in diverse ways. PGPR such as Pseudomonas, Bacillus, Azospirillum, Azotobacter, Arthrobacter, Achromobacter, Micrococcus, Enterobacter, Rhizobium, Agrobacterium, Pantoea and Serratia are now very well known. Rhizomicrobiome plays critical roles in nutrient acquisition and assimilation, improved soil texture, secreting and modulating extracellular molecules such as hormones, secondary metabolites, antibiotics and various signal compounds, all leading to the enhancement of plant growth and development. The microbes and compounds they secrete constitute valuable biostimulants and play pivotal roles in modulating plant stress responses. In this review, we highlight the rhizobacteria diversity and cutting-edge findings focusing on the role of a PGPR in plant growth and development. We also discussed the role of PGPR in resisting the adverse effects arising from various abiotic (drought, salinity, heat, heavy metals) stresses.

Multidimensional Role of Silicon to Activate Resilient Plant Growth and to Mitigate Abiotic Stress.

Sustainable agricultural production is critically antagonistic by fluctuating unfavorable environmental conditions. The introduction of mineral elements emerged as the most exciting and magical aspect, apart from the novel intervention of traditional and applied strategies to defend the abiotic stress conditions. The silicon (Si) has ameliorating impacts by regulating diverse functionalities on enhancing the growth and development of crop plants. Si is categorized as a non-essential element since crop plants accumulate less during normal environmental conditions. Studies on the application of Si in plants highlight the beneficial role of Si during extreme stressful conditions through modulation of several metabolites during abiotic stress conditions. Phytohormones are primary plant metabolites positively regulated by Si during abiotic stress conditions. Phytohormones play a pivotal role in crop plants' broad-spectrum biochemical and physiological aspects during normal and extreme environmental conditions. Frontline phytohormones include auxin, cytokinin, ethylene, gibberellin, salicylic acid, abscisic acid, brassinosteroids, and jasmonic acid. These phytohormones are internally correlated with Si in regulating abiotic stress tolerance mechanisms. This review explores insights into the role of Si in enhancing the phytohormone metabolism and its role in maintaining the physiological and biochemical well-being of crop plants during diverse abiotic stresses. Moreover, in-depth information about Si's pivotal role in inducing abiotic stress tolerance in crop plants through metabolic and molecular modulations is elaborated. Furthermore, the potential of various high throughput technologies has also been discussed in improving Si-induced multiple stress tolerance. In addition, a special emphasis is engrossed in the role of Si in achieving sustainable agricultural growth and global food security.

Assessment of physicochemical parameters of Vishav stream: an important tributary of river Jhelum, Kashmir Himalaya, India.

The deteriorating conditions in stream ecosystems are detrimental for society as far as its health, and development is concerned if the underlying factors continue to operate without regular monitoring. In order to maintain the health of a stream ecosystem, assessment of spatiotemporal changes in its physicochemical attributes and identification of all factors that could alter its hydrological regime is an essential component for managing it. The current 2-year study (October-2017 to September-2019) assessed the physicochemical regime of lower stretches of the Vishav stream, a major left-bank tributary of river Jhelum on a spatiotemporal basis. The physicochemical data was analyzed through linear regression, ANOVA (followed by Duncan's test), multivariate statistical analysis, viz., principal component analysis (PCA) and cluster analysis (CA). Linear regression pointed out the nature and magnitude of the relationship between different physicochemical variables (p < 0.05). PCA showed that WT, pH, EC, NO3-N, TDS, TH, and DO are the major factors reflecting the water quality of the Vishav stream. The range in water quality parameters of the Vishav stream was found conducive for the inhabitant fishes. Two well-defined clusters were obtained, wherein Cluster-I comprising of Site-III (a downstream pollution prone site) and Cluster-II comprising of Site-II and Site-I (mid- and upstream site respectively) are less prone to human interferences. The present study could serve as baseline information to manage and conserve this precious element of the aquatic ecosphere in terms of better water quality for humans and its inhabitant faunal elements especially fish which play a significant role in the economy of that region.

Understanding the spatiotemporal pollution dynamics of highly fragile montane watersheds of Kashmir Himalaya, India.

Pollution of riverine ecosystems through the multidimensional impact of human footprints around the world poses a serious challenge. Research studies that communicate potential repercussions of landscape structure metrics on snowmelt riverine water quality particularly, in climatically fragile Himalayan watersheds are very scarce. Though, worldwide, grasping the influence of land-use practices on water quality (WQ) has received renewed attention yet, the relevance of spatial scale linked to landscape pattern is still elusive due to its heterogenic nature across diverse geomorphic regions. In this work, therefore, we tried to capture the insights on landscape-aquascape interface by juxtapositioning the impacts of landscape structure pattern on snowmelt stream WQ of the whole Jhelum River Basin (JRB) under three varying spatial scales viz., watershed scale, riparian corridor (1000 m wide) and reach buffer (500 m wide). The percentage of landscape pattern composition and configuration metrics in the JRB were computed in GIS utilizing Landsat-8 OLI/TIRS satellite image having 30 m resolution. To better explicate the influence of land-use metrics on riverine WQ with space and time, we used Redundancy analysis (RDA) and multilinear regression (MLR) modeling. MLR selected land-use structure metrics revealed the varied response of WQ parameters to multi-scale factors except for total faecal coliform bacteria (TC) which showed perpetual presence. The reach-scale explained slightly better (76%) variations in WQ than riparian (75%) and watershed (70%) scales. Likewise, across seasonal scale, autumn (75%), winter (83%), and summer (77%) captured the most WQ variation at catchment, riparian, and reach scales respectively. We observed impairing WQ linkages with agriculture, built-up and barren rocky areas across watersheds, besides, pastures in riparian buffer areas, and fragmentation of landscape patches at the reach scale. Due to little appearance of spatial scale differences, a multi scale perspective landscape planning is emphasized to ensure future sustainability of Kashmir Himalayan water resources.

Pathogenesis-related proteins and peptides as promising tools for engineering plants with multiple stress tolerance.

Pathogenesis-related (PR) proteins and antimicrobial peptides (AMPs) are a group of diverse molecules that are induced by phytopathogens as well as defense related signaling molecules. They are the key components of plant innate immune system especially systemic acquired resistance (SAR), and are widely used as diagnostic molecular markers of defense signaling pathways. Although, PR proteins and peptides have been isolated much before but their biological function remains largely enigmatic despite the availability of new scientific tools. The earlier studies have demonstrated that PR genes provide enhanced resistance against both biotic and abiotic stresses, which make them one of the most promising candidates for developing multiple stress tolerant crop varieties. In this regard, plant genetic engineering technology is widely accepted as one of the most fascinating approach to develop the disease resistant transgenic crops using different antimicrobial genes like PR genes. Overexpression of PR genes (chitinase, glucanase, thaumatin, defensin and thionin) individually or in combination have greatly uplifted the level of defense response in plants against a wide range of pathogens. However, the detailed knowledge of signaling pathways that regulates the expression of these versatile proteins is critical for improving crop plants to multiple stresses, which is the future theme of plant stress biology. Hence, this review provides an overall overview on the PR proteins like their classification, role in multiple stresses (biotic and abiotic) as well as in various plant defense signaling cascades. We also highlight the success and snags of transgenic plants expressing PR proteins and peptides.

Physiological and biochemical changes associated with flower development and senescence in so far unexplored Helleborus orientalis Lam. cv. Olympicus.

The so far unexplored H. Orientalis cv. Olympicus exhibits a unique pattern of flower senescence, involving re-greening of creamy white petaloid sepals at the later stages. The greenish sepals become photosynthetically competent immediately after pollination and persist until the seeds are set. After the seed set, the entire (green) flower abscises from the plant. Flower development of Helleborus orientalis cv. Olympicus growing in the open was divided into six stages (I-VI) from tight bud stage to the senescent stage. The average life span of an individual flower after it is fully open is about 6 days. Membrane permeability of sepal tissues estimated as electrical conductivity of leachates increased during senescence. The content of sugars and soluble proteins in the sepal tissues increased during flower opening and declined thereafter during senescence. The protease activity increased as the flower progressed towards senescence. From the present study, it becomes evident that decline in the sugar status and elevation in specific protease activity leading to degradation of proteins are the important factors regulating development and senescence in H. orientalis flowers. Although the tissue content of soluble proteins registered an overall quantitative decrease but SDS-PAGE of protein extract from sepal tissues suggested a decrease in the expression of high molecular weight proteins and an increase in low molecular weight proteins during flower development and senescence. At this stage it is not known whether the polypeptides that increased during senescence play an important role in the senescence of Helleborus orientalis flowers. The increase in these polypeptides during flower senescence is of particular interest because they may be linked to flower longevity. Understanding the nature of these proteins can provide new insights into the pathways that execute senescence and the post-transcriptional regulation of senescence in this flower system.