Biological Control of F. Oxysporum F. Sp. Lycopersici Causing Wilt of Tomato by Pseudomonas Fluorescens

Abstract- Pseudomonas fluorescens is one of the major fungal biocontrol agents found in the soil and the rhizosphere of various crop systems. Ten isolates of P.fluorescens were isolated from rhizosphere soil samples collected from various tomato-growing fields and evaluated for their efficacy in increasing seed quality variables of tomato and in inhibiting the mycelial growth of Fusarium oxysporum. Pseudomonas isolate 2 produced effective results and was selected and mass multiplied. Talc and sodium alginate formulations of mass multiplied using different agents were prepared and evaluated for their effects against fusarium wilt under greenhouse conditions. Fresh cultures of Pf2 isolate was found to increase seedling emergence and reduce fusarium wilt disease incidence when compared to the control and the formulations

Selection of effective bio-​antagonistic bacteria for biological control of tomato wilt caused by Fusarium oxysporum F. sp. lycopersici

Bacteria from the rhizoplane soil and surrounding soil of healthy and Fusarium oxysporum diseased tomato plants of district regions of Karnataka were collected. The best bacterial strains, based on their ability to control development of Fusarium oxysporum isolate, were identified as BS1, BS5 and BS18. All bacterial isolates resulted effective for the in vitro control of growth of Fusarium oxysporum, where the control mechanisms used by the bacteria do not involve the secretion of fungal cell wall hydrolytic enzymes. On the other hand, all bacteria grew well in conditions similar to those that can be found at the field level (considering pH, salinity, Fe3+ and temp.) and showed a good capacity of tomato root colonization. These results suggest that Pseudomonas fluorescens isolates studied have an excellent potential to be used as biocontrol agents of Fusarium oxysporum in tomato greenhouses at the field level

Biochemical characterization of Fusarium oxysporum f. sp. cubense isolates from India

The Fusarium wilt caused by Fusarium oxyspoum f. sp. cubense (Foc) is a major biotic constraint for banana production. The characteristics of F. oxyspoum f. sp. cubense isolates were investigated using electrophoretic studies of isozyme and whole-cell protein. The morphological characteristics of the isolates were very similar to each other. All the Foc isolates were pathogenic to banana cultivar ‘Nanjangud Rasabale’ but they did not induce any disease symptoms on cultivar ‘Cavendish’. F.oxyspoum (Isolate 6) did not induce wilt symptoms on either ‘Nanjangud’ or ‘Cavendish’ cultivar. Isozyme banding patterns showed 46 scoreable markers and cluster analysis with UPGMA using genetic distance showed that the isolates belonged to three main groups. Group 1 contained isolates 1, 2, 4, 5, 7 and isolate 3 and 6 were placed in group 2 and 3. Results indicated that the estimated intraspecific variation may be more pronounced with isozyme analysis than with protein markers. The levelof isozyme variability detected within F. oxysporum f.sp. cubense suggested that it is reliable, efficient and effective in determining genetic relationships among Foc isolates

A Survey on Wireless Network Applications in Automated Public Utilities Control and Management, Journal of Telecommunications and Information Technology, 2015, nr 3

Public utilities such as water, electricity and gas are essential services that play a vital role in economic and social development. Automation of public utility services addresses the huge losses faced by the utility services today, due to non-accounting of distributed utility resources. Automation improves government revenues. The different type of architectures are proposed and designed for automated metering, control and management of public utilities like water, gas, and electricity for effective management and control of resources. The various network topologies, hardware and software architectures to automation and management of public utilities are proposed by researchers. In this paper, the different technologies proposed by various researchers across the globe are surveyed and list of issues and challenges for automated meter reading and control of public utilities is identified

Biochemical characterization of Fusarium oxysporum f. sp. cubense isolates from India

The Fusarium wilt caused by Fusarium oxyspoum f. sp. cubense (Foc) is a major biotic constraint for banana production. The characteristics of F. oxyspoum f. sp. cubense isolates were investigated using electrophoretic studies of isozyme and whole-cell protein. The morphological characteristics of the isolates were very similar to each other. All the Foc isolates were pathogenic to banana cultivar 'Nanjangud Rasabale' but they did not induce any disease symptoms on cultivar 'Cavendish'. F. oxyspoum (Isolate 6) did not induce wilt symptoms on either 'Nanjangud' or 'Cavendish' cultivar. Isozyme banding patterns showed 46 scoreable markers and cluster analysis with UPGMA using genetic distance showed that the isolates belonged to three main groups. Group 1 contained isolates 1, 2, 4, 5, 7 and isolate 3 and 6 were placed in group 2 and 3. Results indicated that the estimated intra-specific variation may be more pronounced with isozyme analysis than with protein markers. The level of isozyme variability detected within F. oxysporum f.sp. cubense suggested that it is reliable, efficient and effective in determining genetic relationships among Foc isolates

Comparative effect of different sugars instigating non-enzymatic browning and Maillard reaction products in guava fruit leather

Browning is a major quality deterioration process affecting both visual colour and nutritional value of guava leather. The aim of the study was to determine the role of different sugars viz., sucrose, fructose, glucose and sorbitol in non-enzymatic browning and antioxidant activity of guava fruit leather. The total free amino acids, ascorbic acid and antioxidant activities were at significantly lower levels in glucose and fructose treated guava leather, while the sorbitol added samples had all of above parameters at the highest level; while a reverse trend was observed in browning index and non-enzymatic browning. Among the browning intermediate products, Hydroxymethylfurfural was present at higher concentration (12.80-32.32 ng/g) than furfural (0.29-0.95 ng/g) in guava leather samples. Among the treatments, hydroxymethylfurfural was found lowest in sorbitol (12.8 ng/g) and highest in fructose (32.3 ng/g). In brief, this paper describes a novel effort in bringing the in-vitro studies related to sugars and total free amino acids, influencing the biochemical and nutritional attributes which are responsible for browning in guava fruit leather

Immunity elicitors for induced resistance against the downy mildew pathogen in pearl millet

Pearl millet (Pennisetum glaucum (L.) R. Br.) is a globally important cereal whose production is severely constrained by downy mildew caused by Sclerospora graminicola (Sacc.). In this study, immunity eliciting properties of 3,5-dichloroanthranilic acid (DCA), Cell Wall Glucan (CWG), Lipopolysaccharide (LPS), and Glycinebetaine (GB) was deciphered through enzymatic and protein studies based on elicitor treatment activated defense mechanisms. Glycinebetaine, LPS, CWS and DCA elicited enzyme activities and gene expression of the defense enzymes, such as β-1,3-glucanase, phenylalanine ammonia lyase (PAL), peroxidase (POX), polyphenol oxidase (PPO), lipoxygenase (LOX) and defense protein hydroxyproline-rich glycoproteins (HRGPs). However, the speed and the extent of elicitation differed. High levels of enzyme activities and gene expression in elicitor-treated P. glaucum positively correlated with the increased downy mildew resistance. A very rapid and large changes in elicitor-treated seedlings, in contrast to the delayed, smaller changes in the untreated susceptible control seedlings suggests that the rate and magnitude of defense gene expression are important for effective manifestation of defense against pathogen. As compared to other elicitors and control, GB promoted increase in enzyme activities and gene expression, implicating that GB is a promising elicitor of downy mildew resistance in P. glaucum

Optimization of factors influencing osmotic dehydration of aonla (Phyllanthus emblica L.) segments in salt solution using response surface methodology

Optimization of process parameters is a critical requirement in food processing and food product industries for the development of highly acceptable product. Quantification of mass transfer kinetics under different processing conditions is essential step for optimizing the osmotic dehydration process. A Box-Behnken Design (BBD), adopted from response surface methodology (RSM) approach was used for evaluating and quantifying the moisture loss and solids gain kinetics of aonla segments in salt solution during the osmotic dehydration process. The independent variables were fixed at three levels (salt concentration- 2, 4, 6%; processtemperature - 45, 50, 55 OC and process time - 60, 120, 180 minutes). The process responses were water loss percentage (WL%) and solids gain percentage (SG%). Validation experiments were conducted at optimum conditions to verify predictions and adequacy of the models. The optimum conditions predicted were 5.02% salt concentration, 54.8 OC temperature and 60.64 minutes process time to attain a desired effect of maximum water loss (6.42%) and minimum solid gain (1.09%) in osmotic dehydration of aonla in salt medium

Fusarium oxysporum f. sp. lycopersici causal agent of vascular wilt disease of tomato: Biology to diversity– A review

Tomato (Lycopersicon esculentum) is one of the widely grown vegetables worldwide. Fusarium oxysporum f. sp. lycopersici (FOL) is the significant contributory pathogen of tomato vascular wilt. The initial symptoms of the disease appear in the lower leaves gradually, trail by wilting of the plants. It has been reported that FOL penetrates the tomato plant, colonizing and leaving the vascular tissue dark brown, and this discoloration extends to the apex, leading to the plants wilting, collapsing and dying. Therefore, it has been widely accepted that wilting caused by this fungus is the result of a combination of various physiological activities, including the accumulation of fungal mycelia in and around xylem, mycotoxin production, inactivation of host defense, and the production of tyloses; however, wilting symptoms are variable. Therefore, the selection of molecular markers may be a more effective means of screening tomato races. Several studies on the detection of FOL have been carried out and have suggested the potency of the technique for diagnosing FOL. This review focuses on biology and variability of FOL, understanding and presenting a holistic picture of the vascular wilt disease of tomato in relation to disease model, biology, virulence. We conclude that genomic and proteomic approachesare greater tools for identification of informative candidates involved in pathogenicity, which can be considered as one of the approaches in managing the disease