Seed treatments for sustainable agriculture-A review

Seed treatment refers to the application of certain agents physical, chemical or biological to the seed prior to sowing in order to suppress, control or repel pathogens, insects and other pests that attack seeds, seedlings or plants and it ranges from a basic dressing to coating and pelleting. Introduction and ban of arsenic (used from 1740 until 1808) is the key milestones in the history of modern seed treatment till then a continuous research and advancement in this technology is going on. The technological advancement prepared a roadmap for refiningexisting seed treatment technologies and future work on technologies like fluid drilling as a way to sow germinated seeds where gel can also serve as a delivery system for other materials, seed priming advances the early phase of germination without redicle emergence. Another advanced technology, solid matrix priming (SMP) has been evaluated as a means to advances the germination of seeds and serve as a carrier for useful material too. Physical and biological seed treatments alone an alternative to chemicals or in combination with a chemical treatment are being used worldwide because of their environmental safety and socioeconomic aspects. Biological seed treatments are expected to be one of the fastest growing seed treatment sectors in the near future, in part because they are easier to register at Environment Protection Agency (EPA). Lack of awareness to seed treatments at farmer’s level is one of the limiting factors in disease management and hence, efforts should be made at farmer’s level to adopt the technology. Keeping the all above facts in mind, selected seed treatment technologies with their improvement and significance will be discussed in this review

Productivity of sodic soils can be enhanced through the use of salt tolerant rice varieties and proper agronomic practices

AbstractRegaining the agricultural potential of sodic soils in the Indo-Gangetic plains necessitates the development of suitable salt tolerant rice varieties to provide an entry for other affordable agronomic and soil manipulation measures. Thus selection of high yielding rice varieties across a range of sodic soils is central. Evaluation of breeding lines through on-station and on-farm farmers’ participatory varietal selection (FPVS) resulted in the identification of a short duration (110–115 days), high yielding and disease resistant salt-tolerant rice genotype ‘CSR-89IR-8’, which was later released as ‘CSR43’ in 2011. Several agronomic traits coupled with good grain quality and market value contributed to commercialization and quick adoption of this variety in the sodic areas of the Indo-Gangetic plains of eastern India. Management practices required for rice production in salt affected soils are evidently different from those in normal soils and practices for a short duration salt tolerant variety differ from those for medium to long duration varieties. Experiments were conducted at the Indian Council of Agricultural Research-Central Soil Salinity Research Institute (ICAR-CSSRI), Regional Research Station, Lucknow, Uttar Pradesh, India during 2011 and 2013 wet seasons, to test the hypothesis that combining matching management practices (Mmp) with an improved genotype would enhance productivity and profitability of rice in sodic soils. Mmp were developed on-station by optimizing existing best management practices (Bmp) recommended for the region to match the requirements of CSR43. The results revealed that transplanting 4 seedlings hill−1 at a spacing of 15×20cm produced significantly higher yield over other treatments. The highest additional net gain was US$3.3 at 90kgha−1N, and the lowest was US$ 0.4 at 150kgha−1N. Above 150kgha−1, the additional net gain became negative, indicating decreasing returns from additional N. Hence, 150kgNha−1 was considered the economic optimum N application rate for CSR43 in these sodic soils. Using 150–60–40–25kg N–P2O5–K2O–ZnSO4·7H2Oha−1 in farmers’ fields grown to CSR43 produced an average of 5.5tha−1 grain. The results of on-farm evaluation trials of CSR43 showed that matching management practices (Mmp) increased yield by 8% over existing best management practices (Bmp) recommended by ICAR-CSSRI for sodic soils and by 16% over framers’ management practices; however, combining Mmp with CSR43 resulted in 35% higher yields over farmers’ current varieties and management. This approach of combining cost effective crop and nutrient management options and a salt-tolerant variety can maximize the productivity and profitability of sodic soils in the alluvial Indo-Gangetic plains and in neighboring salt-affected areas of the Ganges mega delta in South Asia

Development of a Correlation between CoreLok and AASHTO T 85 Tests for Specific Gravity of Coarse Aggregates used in Idaho

UI-20-01Specific gravity and absorption values of coarse aggregates are typically measured in accordance with the AASHTO T 85 standard. The test requires considerable experience to recognize the stage when a soaked sample reaches the saturated surface dry (SSD) condition upon drying. The CoreLok device offers an alternative approach which can be completed in less than 45 minutes compared to the 24 hours required by the AASHTO procedure. This study investigated the results from AASHTO T 85 and CoreLok testing of coarse aggregates to develop a correlation between bulk (dry) specific gravity (Gsb) values measured using the two test procedures. Blended samples, consisting of coarse and fine aggregates, were also tested to evaluate the use of the CoreLok method to reliably determine Gsb values. After testing 15 coarse aggregates and 17 blended aggregates, this study developed three equations that may be used to modify the CoreLok Gsb results to more closely reflect Gsb values based on AASHTO T 85 tests. The recommended equation uses the CoreLok Gsb and the fine aggregate percentage to predict the equivalent AASHTO T 85 Gsb with an R2 = 0.967. Furthermore, five reclaimed asphalt pavement (RAP) materials were also tested to see if the Gsb of the uncoated aggregate could be determined using the CoreLok method. Preliminary results indicate that the CoreLok Gsb results can be reliably calculated if the effective and absorbed binder content is known, or presumed, based on experience

Type III Secretion Is Essential for the Rapidly Fatal Diarrheal Disease Caused by Non-O1, Non-O139 Vibrio cholerae

Cholera is a severe diarrheal disease typically caused by O1 serogroup strains of Vibrio cholerae. The pathogenicity of all pandemic V. cholerae O1 strains relies on two critical virulence factors: cholera toxin, a potent enterotoxin, and toxin coregulated pilus (TCP), an intestinal colonization factor. However, certain non-O1, non-O139 V. cholerae strains, such as AM-19226, do not produce cholera toxin or TCP, yet they still cause severe diarrhea. The molecular basis for the pathogenicity of non-O1, non-O139 V. cholerae has not been extensively characterized, but many of these strains encode related type III secretion systems (TTSSs). Here, we used infant rabbits to assess the contribution of the TTSS to non-O1, non-O139 V. cholerae pathogenicity. We found that all animals infected with wild-type AM-19226 developed severe diarrhea even more rapidly than rabbits infected with V. cholerae O1. Unlike V. cholerae O1 strains, which do not damage the intestinal epithelium in rabbits or humans, AM-19226 caused marked disruptions of the epithelial surface in the rabbit small intestine. TTSS proved to be essential for AM-19226 virulence in infant rabbits; an AM-19226 derivative deficient for TTSS did not elicit diarrhea, colonize the intestine, or induce pathological changes in the intestine. Deletion of either one of the two previously identified or two newly identified AM-19226 TTSS effectors reduced but did not eliminate AM-19226 pathogenicity, suggesting that at least four effectors contribute to this strain’s virulence. In aggregate, our results suggest that the TTSS-dependent virulence in non-O1, non-O139 V. cholerae represents a new type of diarrheagenic mechanism

Peptide-Pulsed Dendritic Cells Induce the Hepatitis C Viral Epitope-Specific Responses of Naïve Human T Cells

Hepatitis C virus (HCV) is a major cause of liver disease. Spontaneous resolution of infection is associated with broad, MHC class I- (CD8+) and class II-restricted (CD4+) T cell responses to multiple viral epitopes. Only 20% of patients clear infection spontaneously, however, most develop chronic disease. The response to chemotherapy varies; therapeutic vaccination offers an additional treatment strategy. To date, therapeutic vaccines have demonstrated only limited success in clinical trials. Vector-mediated vaccination with multi-epitope-expressing DNA constructs provides an improved approach. Highly-conserved, HLA-A2-restricted HCV epitopes and HLA-DRB1-restricted immunogenic consensus sequences (ICS, each composed of multiple overlapping and highly conserved epitopes) were predicted using bioinformatics tools and synthesized as peptides. HLA binding activity was determined in competitive binding assays. Immunogenicity and the ability of each peptide to stimulate naïve human T cell recognition and IFN-γ production were assessed in cultures of total PBMCs and in co-cultures composed of peptide-pulsed dendritic cells (DCs) and purified T lymphocytes, cell populations derived from normal blood donors. Essentially all predicted HLA-A2-restricted epitopes and HLA-DRB1-restricted ICS exhibited HLA binding activity and the ability to elicit immune recognition and IFN-γ production by naïve human T cells. The ability of DCs pulsed with these highly-conserved HLA-A2- and -DRB1-restricted peptides to induce naïve human T cell reactivity and IFN-γ production ex vivo demonstrates the potential efficacy of a multi-epitope-based HCV vaccine targeted to dendritic cells

Efficacy of limonene nano coatings on post-harvest shelf life of strawberries

Strawberries are highly demanded fruits because of their color, nutritional values and appearance. The aim of this study was to develop and characterize alginate and limonene liposomes as edible coating materials and to determine their efficacy in shelf life extension and maintaining quality parameters of ‘Chandler’ strawberries. Alginate solution (1.5% w/v) and Limonene liposomes prepared from 80% lecithin and 20% PDA were used as edible coating materials. Fungal decay percentage, total yeast and mold counts, headspace atmosphere analysis, total soluble solids, pH, titratable acidity, total anthocyanin content and total phenolics were analyzed to assess fruit quality during 14 days at 4 °C of storage. Days of storage was found to be significant in maintaining the quality of the strawberries. Among the coating types, limonene liposomes were found to be significantly more effective in maintaining the lower concentration of carbon dioxide (CO2), lower the change in pH (3.9), and had higher total anthocyanin (43.85) content during storage than those without a liposomal coating. Thus, limonene liposomes were found to be useful for extending the shelf life and maintaining quality of strawberry fruits