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A field trial was conducted in a farmer’s field by integrating biocontrol agents, a multiple insecticide tolerant strain (MITs), Trichogramma chilonis and formulation of Bacillus thuringiensis (NBAIR BtG4) with reduced insecticidal spray as a biocontrol-based IPM compared to insecticidal application as a farmer’s practice, for the management of the diamondback moth (DBM), Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae) infesting cabbage. Six T. chilonis releases of 100,000 parasitized eggs ha− 1 were applied. Along with parasitoid release, a liquid formulation of B. thuringiensis (2%) was applied after third and fifth releases of T. chilonis. The number of P. xylostella larvae were significantly reduced in the field treated with biocontrol-based IPM as compared to farmer’s practice after 30 and 45 days after treatment. After the 45 days, the holes on cabbage leaves were 2.2/plant in the field treated with biocontrol, opposed to 8.0 holes per plant were recorded in the farmer’s practice filed. Only 7% of cabbage head damage was recorded in the field treated with biocontrol, whereas, in farmer’s practice field, those were 32.2%. The cost-benefit analysis showed that integrating these biological control agents along with a reduced number of insecticidal sprays could reduce DBM population and percent head damage with an eventual increase in the yield.

In today's commercial world, multilevel inverters is playing a significant role from power failure. Harmonics is a major problem in power systems that have become serious recently owing to the wide use of power electronics related equipment. In this process, there is a possibility of generation of harmonic peaks because majority of the power utilities are non-linear loads. A high performance multilevel inverter should have a clean output voltage with low total harmonic distortion (THD) for both linear and non linear loads. Harmonic distortion is the most important power quality problem occurring in multilevel inverter, the harmonics can be eliminated by an optimal selection of switching angles. A hybrid evaluation technique evaluates the obtained optimal switching angles that are attained from the fuzzy inference system as well as neural network. The proposed technique is tested with a seven level cascaded H-bridge inverter. The proposed method will be implemented in MATLAB working platform and the harmonic elimination performance will be evaluated.

The baseline-susceptibility of Indian populations of Helicoverpa armigera (Hubner) to the insecticidal protein Cry1Ac, from Bacillus thuringiensis (Berliner) was determined through bioassays conducted in 1999 and 2001. Populations of H. armigera were collected from cotton fields of nine major cotton growing states in India, which included (field locations in parentheses) Punjab (Bathinda), Haryana (Sirsa), Rajasthan (Sriganganagar), Madhya Pradesh (Barwah and Khandwa), Gujarat (Rajkot, Vadodra and Anand), Maharashtra (Jalgoan, Jalna, Akola and Yavatmal), Andhra Pradesh (Adilabad, Warangal, Khammam and Guntur), Karnataka (Raichur, Davangere and Ranebennur) and Tamil Nadu (Coimbatore and Dindigul). All populations were susceptible to Cry1Ac. The mean lethal concentrations, LC50—ranged from 0.14 to 0.71 and from 0.11 to 0.61; LC90 ranged from 1.17 to 6.94 and from 1.02 to 6.70 μg of Cry1Ac / ml of diet in 1999 and 2001 populations, respectively. Similarly, moult inhibitory concentrations, MIC50—ranged from 0.05 to 0.27 and from 0.05 to 0.14; MIC90—values ranged from 0.33 to 1.58 and from 0.25 to 0.91 μg of Cry1Ac in 1999 and 2001 populations, respectively. The effective concentrations (weight stunting related) EC50 ranged from 0.003 to 0.008 and from 0.0003 to 0.004; EC90 ranged from 0.029 to 0.076 and from 0.009 to 0.054 μg of Cry1Ac in 1999 and 2001 populations, respectively. These values form the baseline data for susceptibility of H. armigera to Cry1Ac and can be used as benchmarks for monitoring resistance to Cry1Ac. Bt cotton, expressing Cry1Ac, was approved for commercial cultivation in India in 2002.

Trichogrammatids are being mass reared and released in different ecosystems for control of lepidopterous pests for the past seven decades in India. Indiscriminate use of pesticides often results in decline in the natural enemy population besides development of tolerance in the pests and their resurgence and secondary pest outbreaks. With intensification of agriculture, pesticide consumption has increased drastically from 1950–1951 to 1990–1991 and later decreased from 1991–1992 to 2000–2001 mainly due to integrated approach, environmental concerns, and introduction of newer molecules. Among the major groups of pesticides in India – insecticides are consumed more, followed by herbicides and fungicides. Cotton receives more quantity of the pesticides (52–55 %) followed by paddy (17–18 %) and horticultural crops (13–14 %) as in 2001–2002. In the IPM program, chemical pesticides are integrated with biocontrol methods like release of egg parasitoids and biopesticides. Among 36 species of trichogrammatids described from India, only a few are being commercially mass reared and released. About ten such species have been tested for sensitivity to different pesticide groups. Those already tested include 4 in organochlorine group, 13 in organophosphates group, 12 in synthetic pyrethroid group, 32 in biopesticide group, and 21 in combination compounds for safety to biocontrol agents including trichogrammatids. Out of ten species screened for toxicity to various chemicals, T. chilonis has been more intensively screened against various pesticides by several researchers followed by T. japonicum and T. (= brasiliense) pretiosum. One of the main reasons for T. chilonis being the most widely screened against various pesticides and by various workers is due to its most dominant position in various ecosystems in India and its integration in IPM modules. In the future, studies should be oriented towards the safety of newly introduced pesticides, including combination compounds and biopesticides. Efforts should also be made to better understand the mechanism of populations building up tolerance, besides persistence by using different modern toxicological tools.

The declining activity of the growth hormone--insulin-like growth factor I (IGF-I) axis with advancing age may contribute to the decrease in lean body mass and the increase in mass of adipose tissue that occur with aging.To test this hypothesis, we studied 21 healthy men from 61 to 81 years old who had plasma IGF-I concentrations of less than 350 U per liter during a six-month base-line period and a six-month treatment period that followed. During the treatment period, 12 men (group 1) received approximately 0.03 mg of biosynthetic human growth hormone per kilogram of body weight subcutaneously three times a week, and 9 men (group 2) received no treatment. Plasma IGF-I levels were measured monthly. At the end of each period we measured lean body mass, the mass of adipose tissue, skin thickness (epidermis plus dermis), and bone density at nine skeletal sites.In group 1, the mean plasma IGF-I level rose into the youthful range of 500 to 1500 U per liter during treatment, whereas in group 2 it remained below 350 U per liter. The administration of human growth hormone for six months in group 1 was accompanied by an 8.8 percent increase in lean body mass, a 14.4 percent decrease in adipose-tissue mass, and a 1.6 percent increase in average lumbar vertebral bone density (P less than 0.05 in each instance). Skin thickness increased 7.1 percent (P = 0.07). There was no significant change in the bone density of the radius or proximal femur. In group 2 there was no significant change in lean body mass, the mass of adipose tissue, skin thickness, or bone density during treatment.Diminished secretion of growth hormone is responsible in part for the decrease of lean body mass, the expansion of adipose-tissue mass, and the thinning of the skin that occur in old age.