Notice     

N. Natarajan  P. C. Sundara Babu 《国际虫害防治杂志》2013,59(3):338-340

Abstract

The seasonal occurrence of gram pod borer, Heliothis armigera Hb. in sorghum during cropping periods was studied. The incidence of H. armigera larvae was highest between March and June, 1984. This gradually decreased between July and October, 1984 and was lowest between January and March, 1985. Larval counts were found to be higher on the cultivar CSH 5 than K‐tall. The main crop of first two cropping seasons harboured more larvae than the ratoon crops while in third cropping period there was no significant difference.  相似文献   

Influence of weather factors on sorghum earhead bug Calocoris angustatus Lethierry incidence     

N. Natarajan  P. C. Sundara Babu  S. Chelliah 《国际虫害防治杂志》2013,59(4):413-420

Abstract

Weather parameters during the same week and one, two, three or four weeks before were correlated with the population of earhead bug, Calocoris angustatus on different earhead stages of two hybrids, CSH 5 and K‐Tall, in main and ratoon crops. The weather factors in the different weeks contributing to the insect population varied with the stage of earhead, the hybrid and the nature of the crop (main or ratoon). In the main crop, the insect population at pre‐flowering, milky, dough and maturity stage was influenced by weather parameters one week before, the same, two and three weeks before respectively. Morning relative humidity was important in both hybrids at all stages, with a few exceptions. In the ratoon crop, the pre‐flowering and maturity stage populations were influenced by the weather parameters of the same week. The populations at milky and maturity stage were influenced by parameters four weeks and one week before the observations respectively. The factors influencing the population on CSH 5 and K‐Tall varied. In most cases morning relative humidity had a positive influence.  相似文献   

Studies on the sorghum grain midge,Contarinia sorghicola Coquillet,in relation to environmental influence     

K. Natarajan  S. Chelliah 《国际虫害防治杂志》2013,59(4):276-285

Abstract

Biology, ecology and damage potential of the sorghum midge, Contarinia sorghicola Coquillet, were studied at Coimbatore, India. The life cycle of the midge was shorter in summer than winter: Johnson grass, Sorghum halepense and pearl millet, Pennisetum americanum served as alternate hosts for the sorghum midge. Seasonal incidence studies revealed that four peak infestations occurred in crops sown in April, June, August and October. Midge developmental stages were quite active all through the year with no diapause, Peak adult midge attraction to the light trap was recorded at 21.00 hours. However, adult midges were found to be quite active only in the daytime in the field. There was no relationship between adult midge catches from the light trap and the population recorded in the field. Morning relative humidity and wind velocity were negatively associated with the population of midge attracted to the light trap. An increased percentage of midge population was recorded in the light trap during the new moon and second quarter phases of moon. Sticky traps were not efficient in trapping adult midges. One pair of adult midge per earhead caused 16–9% grain damage.  相似文献   

Hypoglycemic effect of Mucuna pruriens seed extract on normal and streptozotocin-diabetic rats     

Bhaskar A  Vidhya VG  Ramya M 《Fitoterapia》2008,79(7-8):539-543

The hypoglycemic effect of the aqueous extract of the seeds of Mucuna pruriens was investigated in normal, glucose load conditions and streptozotocin (STZ)-induced diabetic rats. In normal rats, the aqueous extract of the seeds of Mucuna pririens (100 and 200 mg/kg body weight) significantly (P<0.001) reduced the blood glucose levels after an oral glucose load from 127.5+/-3.2 to 75.6+/-4.8 mg% 2 h after oral administration of seed extract. It also significantly lowered the blood glucose in STZ diabetic rats from 240.5+/-7.2 to 90.6+/-5.6 mg% after 21 days of daily oral administration of the extract (P<0.001). Thus, this study shows that M. pruriens has an anti-hyperglycemic action and it could be a source of hypoglycemic compounds.  相似文献   

Management practices followed for draught cattle in the southern part of India   总被引：1，自引：1，他引：0  

Natarajan Akila  Mahesh Chander 《Tropical animal health and production》2010,42(2):239-245

A study was conducted to determine the management practices followed by the farmers for draught cattle in Tamil Nadu state, India. Methods of procurement of animals, use of female animals, breeds preferred, housing, health, disposal of animals, feeding, shoeing, purchase of animal-drawn implements and their maintenance were all assessed with 210 farmers from seven districts across different agro-climatic zones in Tamil Nadu. The results revealed that 86 % of the respondents purchased the draught cattle from the livestock markets, most were bullocks but 20 small farmers and 5 medium farmers used female animals for ploughing. Among the indigenous breeds, Kangeyam (33 %) and Hallikar (30 %) breeds were the most popular for work. Most farmers (69 %) provided a mixed type of housing (provision of housing only during the night time and the rainy season) for their draught cattle. The major health problem reported by 63 % of respondents was pyrexia. Almost all farmers sold their animals at the age of 8–10 years. The feeding practices for draught cattle were poor especially with the small farmers. The cattle were fed with mainly paddy straw and rice bran. Oilcakes and cotton seeds were given to the animals which work throughout the year mainly for ploughing and carting. The draught cattle were first shod at around 2.5 years of age. The majority of the farmers (71 %) used the traditional animal-drawn implements made by local artisans, and the farmers were not aware of the new implements to reduce the drudgery of work cattle, designed by the Agricultural Machinery Research Centre and Agricultural Engineering Departments located in India.  相似文献   

Effect of probiotic supplementation on growth,nitrogen utilisation and serum cholesterol in broilers     

B. Mohan  R. Kadirvel  A. Natarajan  M. Bhaskaran 《British poultry science》1996,37(2):395-401

1. The effect of dietary probiotic supplementation on the growth, nitrogen utilisation and serum cholesterol content of broiler chickens was studied in 2 trials.

2. In experiment 1, the birds receiving the 0, 75, 100, 125 mg probiotic/kg diets had weight gains of 1204.0, 1272.0, 1268.3 and 1210.5 g, respectively at the end of 8 weeks of feeding. The group of birds fed on the 75 mg probiotic supplemented diet retained significantly (P<0.01) more nitrogen than the control birds. Serum cholesterol content was lower in the probiotic‐supplemented birds (93.3 mg/100 ml) compared to the control birds (132.2 mg/100 ml).

3. In the second experiment the probiotic plus antibiotic‐supplemented group of birds had the maximum weight gain (1148.5 g) followed by antibiotic (1141.3 g), probiotic‐supplemented (1128.4 g) and control birds (1045.6 g) after 6 weeks. Nitrogen retention was greatest in the antibiotic—(48.5%) followed by the probiotic—(46.5%), probiotic plus antibiotic‐supplemented groups (46.3%) compared to 40.2% in control birds.

4. The apparent metabolisable energy was greatest in birds receiving the probiotic plus antibiotic‐supplemented diet (12.37 MJ/kg) followed by antibiotic—(12.00 MJ/kg), probiotic‐supplemented birds (11.92 MJ/kg) than in control birds (11.62 MJ/kg). Serum cholesterol was significantly (P<0.01) lower in probiotic‐supplemented birds (86.1 mg/dl) compared to 118.4 mg/dl in control birds.  相似文献   

NSF and Science Education     

Natarajan KV 《Science (New York, N.Y.)》1981,212(4499):1085-1086

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Neem oil (Azadirachta indica) nanoemulsion--a potent larvicidal agent against Culex quinquefasciatus     

Anjali CH  Sharma Y  Mukherjee A  Chandrasekaran N 《Pest management science》2012,68(2):158-163

BACKGROUND: Nanoemulsion composed of neem oil and non‐ionic surfactant Tween 20, with a mean droplet size ranging from 31.03 to 251.43 nm, was formulated for various concentrations of the oil and surfactant. The larvicidal effect of the formulated neem oil nanoemulsion was checked against Culex quinquefasciatus. RESULTS: O/W emulsion was prepared using neem oil, Tween 20 and water. Nanoemulsion of 31.03 nm size was obtained at a 1:3 ratio of oil and surfactant, and it was found to be stable. The larger droplet size (251.43 nm) shifted to a smaller size of 31.03 nm with increase in the concentration of Tween 20. The viscosity of the nanoemulsion increased with increasing concentration of Tween 20. The lethal concentration (LC₅₀) of the nanoemulsion against Cx. quinquefasciatus was checked for 1:0.30, 1:1.5 and 1:3 ratios of oil and surfactant respectively. The LC₅₀ decreased with droplet size. The LC₅₀ for the ratio 1:3 nanoemulsions was 11.75 mg L^?1. CONCLUSION: The formulated nanoemulsion of 31.03 nm size was found to be an effective larvicidal agent. This is the first time that a neem oil nanoemulsion of this droplet size has been reported. It may be a good choice as a potent and selective larvicide for Cx. quinquefasciatus. Copyright © 2011 Society of Chemical Industry  相似文献   

Relative effects of parents on some economic characters in sugarcane     

B. V. Natarajan  T. N. Krishnamurthy  J. Thuljaram Rao 《Euphytica》1967,16(1):104-108

Studies on the relative effects of parents on some economic characters in sugarcane have given indications of maternal influence in the progeny performance in certain crosses with regard to millable canes at harvest, height of stalks and brix per cent in juice, irrespective of the fact that pollen parent effect was positive or negative. As judged from a study of the progeny of the direct crosses and reciprocals among the varieties studied, particularly use of Co. 678 as a pistil parent in the breeding programme for improving the mean height of the progeny and Co. 527 as a pistil parent for increasing number of millable canes at harvest and brix per cent in juice is clearly indicated. These indications should also prove useful for application in adopting the polycross method of breeding as well.  相似文献   

Flat fish eggs,larvae and their development     

N. Ramanathan  R. Natarajan 《Aquaculture (Amsterdam, Netherlands)》1979,18(4):349-366

Studies on development of eight species of flat fishes (Psettodes erumei, Brachypleura novae-zeelandiae, Pseudorhombus arsius, Bothus myriaster, Synaptura albomaculata, S. commersoniana, Cynoglossus arel and C. monopus) were carried out with plankton collections and with laboratory reared larvae. The development stages of Cynoglossus arel and C. monopus from egg to metamorphosis are described.  相似文献