Induction of resistance in tomato against Helicoverpa armigera (Hubner) using biofertilizers

Based on preliminary and confirmatory field screening of 321 tomato accessions for resistance against fruit borer, Helicoverpa armigera (Hubner), a promising accession Varushanadu Local was selected for studying induction of resistance using biofertilizers viz., Azospirillum, Phosphobacteria, Pseudomonas and K-solubilizer. In comparison, a susceptible check, I979 was also evaluated. The feeding preference of H. armigera larva was the least towards Varushanadu Local than I979 irrespective of the biofertilizer. Among the biofertilizers K-solubilizer treated plants were the least preferred than others. A trend was observed in both the free choice and confinement tests. ÂÂ

In vitro Efficacy of Beauveria bassiana (Bals.) Vuill. and Verticillium lecanii (Zimm.) viegas against selected insect pests of cotton

The bioefficacy of selected entomopathogenic fungi viz. Beauveria bassiana (Bals.) Vuill. against Heliothis armigera Hubner, Spodoptera litura Fabricius, Earias vittella Fabricius and Verticillium lecanii (Zimm.) Viegas against Aphis gossypii Glover, Bemisia tabaci Gennadius and Amrasca devastans Distant was studied under laboratory conditions at Department of Entomology, Faculty of Agriculture, Annamalai University, Annamalainagar, Tamilnadu, India during 2007-2008. Three different concentrations viz., 0.15, 0.20 and 0.25 per cent of liquid formulation of these entomopathogenic fungi were tested to evaluate the effective concentration. Among the three concentrations, 0.25 per cent recorded the highest mortality of H. armigera (86.67 %), S. litura (86.67 %), E. vittella (73.33 %), A. gossypii (100.00 %), B. tabaci (100.00 %) and A. devastans  (93.33 %) respectively.ÂÂ

Studies on the seasonal incidence of sugarcane internode borer, Chilo saccariphagus indicus (kapur) in Tamil Nadu, India

Internode borer (INB), Chilo saccariphagus indicus (Kapur) (Lepidoptera: Pyraustidae) is an important pest on sugarcane which inflicts yield loss of about than 45 per cent. Pest surveillance and forecasting is one of the important prerequisite tools in managing such pests. Hence, an attempt was made to study the seasonal incidence of the INB during 2007 and 2008 at Nellikuppam, Tamil Nadu, India. The study revealed that the peak incidence of INB was observed during June-July, which declined thereafter. Higher temperature and deficit or failure of rainfall during March –May are considered as the favourable factors for the rise in the incidence of INB

Field evaluation of sunflower (Helianthus annuus L.) accessions for resistance against leaf hopper, Amrasca biguttula biguttula (Ishida)

One hundred and twelve accessions of sunflower (Helianthus annuus L.) were screened under field conditions in two seasons at Sambavar Vadakarai and Udappankulam villages of Tirunelveli district of Tamilnadu, India during January to April and June to September, 2009 respectively for their resistance against leaf hopper (Amrasca biguttula biguttula Ishida). Observations on the number of nymphs/adults per plant were recorded at weekly interval. In the first season, four accessions viz., KBSH 1, AHT 14, GK 2002 and GMU 698 harboured the least population whereas in the second season, the accession KBSH 1 proved to be promising

Biochemical components of wild relatives of chickpea confer resistance to pod borer, Helicoverpa armigera

Efforts are being made to develop chickpea varieties with resistance to the pod borer, Helicoverpa armigera for reducing pesticide use and minimizing the extent of losses due to this pest. However, only low to moderate levels of resistance have been observed in the cultivated chickpea to this polyphagous pest. Hence, it is important to explore wild relatives as resistance sources to develop insect-resistant cultivars. Therefore, we studied different biochemical components that confer resistance to H. armigera in a diverse array of wild relatives of chickpea. Accessions belonging to wild relatives of chickpea exhibited high levels of resistance to H. armigera as compared to cultivated chickpea genotypes in terms of lower larval survival, pupation and adult emergence, decreased larval and pupal weights, prolonged larval and pupal developmental periods and reduced fecundity of the H. armigera when reared on artificial diet impregnated with lyophilized leaf powders. Amounts of proteins and phenols in different accessions of chickpea wild relatives were significantly and negatively correlated with larval weight, pupation and adult emergence. Phenols showed a negative correlation with pupal weight and fecundity, but positive correlation with pupal period. Total soluble sugars showed a negative correlation with larval period, but positive correlation with pupation and pupal weight, while tannins showed a positive correlation with larval weight, pupation and adult emergence. The flavonoid compounds such as chlorogenic acid, ferulic acid, naringin, 3,4-dihydroxy flavones, quercetin, naringenin, genistein, biochanin-A and formononetin that were identified through HPLC fingerprints, exhibited negative effects on survival and development of H. armigera reared on artificial diet impregnated with lyophilized leaf powders. The wild relatives with diverse mechanisms of resistance conferred by different biochemical components can be used as sources of resistance in chickpea breeding programs to develop cultivars with durable resistance to H. armigera for sustainable crop production

Effects of Thermal Degradation on Carbon Reinforced PEEK Composites

The application of fibre reinforced thermoplastic composites in aerospace industry has increased drastically in the last decade. Carbon fibre/Polyether-ether-ketone (C/PEEK) is one of the high-performance thermoplastic composites and is replacing metallic and thermosetting counterparts in various aircrafts components. Parts made from such composites undergo multiple heat treatment cycles, and each cycle involves processing at temperatures above melt. At these temperatures, thermal stability is a limiting factor, which results in severe thermal degradation of the polymer, especially in oxidative environments. For this project, the thermal degradation of 8-ply unidirectional C/PEEK composites is investigated. The objectives include finding the reduction in morphological properties of PEEK polymer due to degradation over four different processing temperatures (385, 405, 425, and 445°C), and times (10, 30, 60, and 90 minutes), in two processing environments (air and nitrogen), exploring the effect of oxygen and temperature on degradation, and evaluating the mechanical performance through three-point bending. Thermal analysis through Differential Scanning Calorimetry (DSC) showed that the crystallinity reduces from 32% for an untreated laminate to 28% for the lowest heat treatment condition (385°C, 10 minutes). From there, a steady reduction is observed, with 15% at 425°C, 60 minutes, and 0% at 425°C, 90 minutes and 445°C, 90 minutes. A contour plot for polymer property reduction based on crystallinity serves as a processing guideline for C/PEEK laminates. DSC analysis through the thickness of air treated laminates showed that surface plies degrade faster than the inner plies. This effect is not observed in a nitrogen environment. This showed the effect of oxygen on the surface. Though inner plies were shielded from oxygen exposure, they still showed a higher degradation than nitrogen treated laminates, showing that diffusion of oxygen through the laminates has taken place. At 425°C and 445°C, in air, the through thickness difference is higher compared to 385°C. So, in oxygen environment, polymer degrades faster at higher temperatures than at lower temperatures. In nitrogen, at 385°C, there is almost no degradation, whereas the other three temperatures show an increased degradation. The rate of degradation in different environments and at different temperatures is characterized by computation of activation energies. The air treated laminates showed an activation energy of 126 kJ/mol, whereas, nitrogen treated laminates has 193 kJ/mol. 3-point bending tests are performed to observe matrix failure. No failure was observed at 10, 30, and 60 minutes at 385°C, but from 405°C, cracks starts to appear and cracks initiates at lower stresses with increasing heat treatment conditions.Aerospace Engineering | Novel Aerospace Material

Enhancing the efficacy and persistency of <i>Spodoptera litura </i>(Fab.) nuclear polyhedrosis virus using UV irradiation protectants

1175-1176To enhance the field persistency of S. litura nuclear polyhedrosis virus (SLNPV), three chemicals viz. cupric ammonium nitrate, tinopal and cupric sulphate were tried as protectants (0.01 mg/ml) against natural sunlight (UV) irradiation. On exposure for 8 hr and subsequent bioassaying (diet surface treatment), it was found that cupric sulphate protected the polyhedrosis inclusion bodies (PIBs), recording 95.56 % mortality which was statistically at par with unexposed PIBs recording 97.78% mortality

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Not AvailableConogethes sp. is a large taxon that infests more than 120 wild and cultivated host plants across the world. So far, several scientists have studied this group of moth pests to appreciate the genetic variability in the genus; however, owing the complexity at genetic and ecological levels, it has become difficult to understand this group of moths. Till date 24 species have been deposited in the Barcode of Life Data (BOLD) system. In order to study the molecular diversity of Conogethes, multiple markers have been used world over. However, several researchers have revealed that combined analysis of molecular markers and morphological data with field observations may constitute powerful evidence for proper identification of pest species in this problematic taxa. Precise identification would then be utilized for developing realistic practices for the management of Conogethes sp. in diversified cultivated ecosystems.Not Availabl