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The phyllosphere supports a tremendous diversity of microbes and other organisms. However, little is known about the colonization and survival of pathogenic and beneficial bacteria alone or together in the phyllosphere across the whole plant life-cycle under herbivory, which hinders our ability to understand the role of phyllosphere bacteria on plant performance. We addressed these questions in experiments using four genetically and biogeographically diverse accessions of Arabidopsis thaliana, three ecologically important bacterial strains (Pseudomonas syringae DC3000, Xanthomonas campestris, both pathogens, and Bacillus cereus, plant beneficial) under common garden conditions that included fungus gnats (Bradysia spp.). Plants supported greater abundance of B. cereus over either pathogenic strain in the phyllosphere under such greenhouse conditions. However, the Arabidopsis accessions performed much better (i.e., early flowering, biomass, siliques, and seeds per plant) in the presence of pathogenic bacteria rather than in the presence of the plant beneficial B. cereus. As a group, the plants inoculated with any of the three bacteria (Pst DC3000, Xanthomonas, or Bacillus) all had a higher fitness than uninoculated controls under these conditions. These results suggest that the plants grown under the pressure of different natural enemies, such as pathogens and an herbivore together perform relatively better, probably because natural enemies induce host defense against each other. However, in general, a positive impact of Bacillus on plant performance under herbivory may be due to its plant-beneficial properties. In contrast, bacterial species in the mixture (all three together) performed poorer than as monocultures in their total abundance and host plant growth promotion, possibly due to negative interspecific interactions among the bacteria. However, bacterial species richness linearly promoted seed production in the host plants under these conditions, suggesting that natural enemies diversity may be beneficial from the host perspective. Collectively, these results highlight the importance of bacterial community composition on plant performance and bacterial abundance in the phyllosphere.

The molecular marker is a useful tool for assessing genetic variations and resolving cultivar identities. Information on genetic diversity and relationships among rice genotypes from Pakistan is currently very limited. The objective of this study was to evaluate the genetic polymorphisms and identities of 10 traditional, 28 improved and 2 Japanese cultivars of rice using the random amplified polymorphic DNA technique. Twenty-five decamer-primers could generate a total of 208 RAPD fragments, of which 186 or 89.4% were polymorphic. The number of amplification products produced by each primer varied from 4 to 16 with an average of 8.3 bands primer -1 . The size of amplified fragments were ranged from 200 to 4000 bp. Pair-wise Nei and Li's similarity had estimated the range of 0.50 to 0.96 between rice cultivars. Based on analysis performed on a similarity matrix using UPGMA, 40 cultivars were grouped into 3 main clusters corresponding to aromatic, non-aromatic and japonica group. There were a few of independent cultivars. The cluster analysis had placed most of the aromatic cultivars into a close relation showing a high level of genetic relatedness. However, the clusters formed by the *Corresponding author aromatic cultivars were distinct from those of nonaromatic and japonica types. Interestingly, a number of improved and traditional cultivars originating from diverse sources did not form well defined groups and were interspersed, indicating no association between the RAPD patterns and the geographic origin of the cultivars. The information generated from this study can be used to maximize selection of diverse parents and broaden the germplasm base in the future of rice breeding programs.Rice (Oryza sativa L.) is one of the most important crops that provide food for more than half of the world population. It is no longer a luxury food but has become the cereal that constitutes a major source of calories for the urban and the rural (Sasaki and Burr, 2000). Rice is cultivated in a wide range of ecological environments worldwide. Pakistan is one of the few countries which had an enormous wealth of aromatic rices and old landraces. Many have been lost during the last three decades after green revolution. A number of traditional varieties and improved cultivars have been released for cultivation in different regions of Pakistan since the early nineteen

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The continuous cropping (CC) of major agricultural, horticultural, and industrial crops is an established practice worldwide, though it has significant soil health-related concerns. However, a combined review of the effects of CC on soil health indicators, in particular omics ones, remains missing. The CC may negatively impact multiple biotic and abiotic indicators of soil health, fertility, and crop yield. It could potentially alter the soil biotic indicators, which include but are not limited to the composition, abundance, diversity, and functioning of soil micro- and macro-organisms, microbial networks, enzyme activities, and soil food web interactions. Moreover, it could also alter various soil abiotic (physicochemical) properties. For instance, it could increase the accumulation of toxic metabolites, salts, and acids, reduce soil aggregation and alter the composition of soil aggregate-size classes, decrease mineralization, soil organic matter, active carbon, and nutrient contents. All these alterations could accelerate soil degradation. Meanwhile, there is still a great need to develop quantitative ranges in soil health indicators to mechanistically predict the impact of CC on soil health and crop yield gaps. Following ecological principles, we strongly highlight the significance of inter-, mixture-, and rotation-cropping with cover crops to sustain soil health and agricultural production.

The findings have demonstrated that early transient sphingosine‐1 phosphate lyase inhibition after acute myocardial infarction (AMI) correlates with increased stem cell mobilization and homing to the infarct border zones. These data indicate that pharmacological elevation of bioactive lipid levels can be beneficial in the early phase after cardiac ischemic injury and provide the first evidence that carefully timed transient pharmacological upregulation of bioactive lipids after AMI could be therapeutic.

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