Incidence of Debarking by Caterpillar, Indarbela quadrinotata Walker on Casuarina equisetifolia in Tamil Nadu and its Management

2019 ◽  
Vol 42 (3) ◽  
pp. 225-230
Author(s):  
K.R. Sasidharan ◽  
◽  
G. Ramesh ◽  

Casuarina equisetifolia is an exotic, fast growing, multipurpose tree species grown in Tamil Nadu. Altogether, about 40 species of insects have been recorded on C. equisetifolia in Tamil Nadu State. Among them, the bark eating caterpillar, Indarbela quadrinotata is considered as the most destructive pest in plantations. Wide variation in the infestation levels of bark eating caterpillar was noticed in Casuarina plantations grown under four agro-climatic zones of Tamil Nadu; the Cauvery Delta Zone showed highest intensity of attack, followed by the North Eastern Zone and the Southern Zone in the decreasing order of infestation, while the High Rainfall Zone was not affected by the pest. Plantations of younger age suffered from higher levels of infestation, compared to that of older ones. Among the climatological parameters, the minimum temperature had significant positive correlation with the pest infestation. Apart from the naturally occurring entomopathogenic fungus, Beauveria bassiana, the botanical formulations such as Melia azedarach seed kernel extract (5%), Pongamia pinnata seed oil (5%), Hydnocarpus pentandra seed oil (10,000 ppm) and Neem oil (5%) were found to be very effective in managing the pest under field condition.

2009 ◽  
Vol 23 (4) ◽  
pp. 633-647 ◽  
Author(s):  
V. Geethalakshmi ◽  
Akiyo Yatagai ◽  
K. Palanisamy ◽  
Chieko Umetsu

2004 ◽  
Vol 2 (2) ◽  
pp. 1-7
Author(s):  
J. Diraviam ◽  
M. Selvanayagam ◽  
S. Ignacimuthu

Agricultural systems are often considered by ecologists as disturbed, depauperate, and evolutionarily recent. But tropical rice agro-ecosystem is one exception due to its ecological complexity resulted by the long ecological complexity resulted by the long ecological history and wide geographical distribution. Rice nursery is very similar to natural grassland and offers a wide scope for studying the biodiversity due to the presence of arthropod fauna. A survey was conducted in five rice nursery fields in the same period in three villages of two districts of the north eastern zone of Tamil Nadu: Budur, Kavarapettai and Narasingapuram of Tiruvallur district, and Kavur and Malaiyambakkam of Kancheepuram district during Sornavari season,2003(April to August). The rice cultivar was uniformly ADT 43, a short duration variety. No chemical pesticide was applied in the nursery fields and the seedlings were of uniform age. Fifty double sweep net samples were taken to study arthropod diversity. The specimens sorted out were grouped into three guilds, viz., pests, entomophages and neutrals, and their relative abundance was worked out. . The overall observations revealed that a wide range of arthropod fauna were present in the rice nursery fields. The neutrals were the most dominant guilds in four out of five locations. The relative abundance range from 30.22 to 67.13% .This guild was followed by the pests, which ranged from 17.5 to 48.58%. The abundance of entomophages ranged from 13.32 to 24.36%. Among the locations, the maximum relative abundance of pest and entomophage guilds was observed in Narasingapuram. The maximum relative abundance of neutrals was observed in Budur. The green leaf hopper, white flies, white-bat plant hopper, grass hoppers and trips were the major pests. The pre dominant entomophages were the spiders, parasitic hymenoptera and ground beetles. Dipteran flies and hydrophilids were the pre dominant neutrals observed. It may be concluded that rice nursery field supports a wide range of arthropods. The neutrals help in the buildup of carnivorous (entomophages), which ultimately check the pest population.


GIS Business ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. 230-242
Author(s):  
M. Ganesan, K ◽  
K. Veerakumar ◽  
N. R Vembu ◽  
Dr. M. K Durgamani ◽  
Dr. Renuka

Job satisfaction is an important factor for employees working in formal and informal sector. The job is small or big, permanent or temporary, risky or non-risky, job satisfaction is important. It is the mental feeling which drives the employees to excel. Job satisfaction is a combination of psychological, physiological and environmental circumstances. A satisfied employee is a contented and happy human being. The labour turnover depends upon job satisfaction. Even highly paid employees quit the job when they are not satisfied with the job. Road transportation in Tamilnadu is growing day by day. Job stress in the road transportation is very high due to increase in number of vehicle playing on the road and heavy traffic. The drivers and conductors working in public transport corporation are suffering from high job stress. If drivers and conductors are not satisfied with their job which leads to mental stresses and affects the productivity and also creates accidents. In this present study the researchers made an attempt to study the level of job satisfaction among the drivers and conductors who are working in the Tamilnadu State Transport Corporation (TNSTC). The study reveals the expectations of drivers and conductors working in TNSTC with regards to the attributes like salary, promotion and fringe benefits etc., are satisfactory and not detrimental. 


2019 ◽  
Vol 56 (3) ◽  
pp. 294-304
Author(s):  
C Sharmila Rahale

Six field experiments were conducted at Tamil Nadu Rice Research Institute, Aduthurai to evolve suitable zinc fertilization method for rice - rice (Oryza sativa L.) cropping system in Cauvery delta zone. The treatment includes: T1 : Control, T2 : 100 g zinc sulphate (ZnSO4)/cent in nursery alone., T3 : root dipping alone in 2 % zinc oxide (ZnO) solution, T4 : 25 kg ZnSO4 ha-1, T5 : 37.5 kg ZnSO4 ha-1, T6 : 25 kg ZnSO4 ha-1+ Farm Yard Manure (FYM) 12.5 t ha-1, T7 : 25 kg ZnSO4 ha-1 + Green Leaf Manure (GLM) 6.5 t ha-1, T8 : Tamil Nadu Agricultural University Micro Nutrient (TNAU MN) mixture 25 kg ha-1 as Enriched Farm Yard Manure (EFYM), T9 : TNAU MN mixture 37.5 kg ha-1 as EFYM, T10 : Foliar spray of 0.5% ZnSO4 + 1 % urea at tillering and panicle initiation stage, T11 : 100g ZnSO4 /cent in nursery alone + Foliar spray of 0.5 % ZnSO4 + 1 % urea at tillering and panicle initiation stage (T2+ T10), T12 : root dipping alone in 2 % ZnO solution + Foliar spray of 0.5 % ZnSO4 + 1 % urea at tillering and panicle initiation stage (T3 + T10), T13: 100 g ZnSO4 /cent in nursery alone + root dipping alone in 2 % ZnO solution + Foliar spray of 0.5 % ZnSO4 + 1 % urea at tillering and panicle initiation stage (T2 + T3 + T10). The treatments T5, T6, T7 and T9 were skipped in rabi season to know the residual effect of these treatments in the subsequent season. Among the treatment combinations, application of 25 kg ZnSO4 ha-1 + FYM 12.5 t ha-1 recorded higher grain yield in both kharif (6232 kg ha-1) and rabi (6236 kg ha-1) seasons. The same treatment combination recorded higher Zn content and Zn uptake as well. Regarding soil nutrient content, the same treatment recorded higher N, P and K content. This treatment was followed by application of 25 kg ZnSO4 ha-1 + green leaf manure 6.5 t ha-1. The experimental findings suggested that combination of organic and inorganic sources not only increased the yield but also improves soil health in Cauvery delta zone.


2021 ◽  
Vol 58 (5) ◽  
pp. 567-576
Author(s):  
Ronald G. Munger ◽  
Rajarajeswari Kuppuswamy ◽  
Jyotsna Murthy ◽  
Kalpana Balakrishnan ◽  
Gurusamy Thangavel ◽  
...  

Background and Objective: The causal role of maternal nutrition in orofacial clefts is uncertain. We tested hypotheses that low maternal vitamin B12 and low folate status are each associated with an increased risk of isolated cleft lip with or without cleft palate (CL±P) in a case–control study in Tamil Nadu state, India. Methods: Case-mothers of CL±P children (n = 47) and control-mothers of unaffected children (n = 50) were recruited an average of 1.4 years after birth of the index child and plasma vitamin B12, methylmalonic acid (MMA), total homocysteine (tHcy), and folate were measured at that time. Logistic regression analyses estimated associations between nutrient biomarkers and case–control status. Results: Odds ratios (ORs) contrasting biomarker levels showed associations between case-mothers and low versus high plasma vitamin B12 (OR = 2.48, 95% CI, 1.02-6.01) and high versus low plasma MMA, an indicator of poor B12 status (OR = 3.65 95% CI, 1.21-11.05). Case–control status was not consistently associated with folate or tHcy levels. Low vitamin B12 status, when defined by a combination of both plasma vitamin B12 and MMA levels, had an even stronger association with case-mothers (OR = 6.54, 95% CI, 1.33-32.09). Conclusions: Mothers of CL±P children in southern India were 6.5 times more likely to have poor vitamin B12 status, defined by multiple biomarkers, compared to control-mothers. Further studies in populations with diverse nutritional backgrounds are required to determine whether poor maternal vitamin B12 or folate levels or their interactions are causally related to CL±P.


Water Policy ◽  
2008 ◽  
Vol 10 (4) ◽  
pp. 391-407 ◽  
Author(s):  
K. Palanisami ◽  
A. Vidhyavathi ◽  
C. R. Ranganathan

Groundwater depletion is experienced in several districts of Tamil Nadu state and Coimbatore district is heading in that direction. The average well failure rate is 47% for open wells and 9% for bore wells. The total cost of depletion for new wells varies from Rs 1,999 per ha to Rs 90,975 per ha. The electricity subsidy to the farmers has varied from Rs 22,621 per ha for coconut growers to Rs 25,498 per ha for banana growers as on 2004. The cost of irrigation per cubic metre (m3) is less on large farms. The average net return with free electricity varies from Rs 0.14 per m3 to Rs 1.38 per m3 and is drastically reduced when electricity is priced at an economic cost, i.e. Rs −1.15 to Rs −0.14 per m3. The shift in cropping pattern towards high value crops helped the farmers to some extent to bear the cost of externalities arising out of depletion. The social cost caused by groundwater overdraft is about Rs 554.3 million, which may increase when the well density increases further. Suggested policy options are to change the cropping pattern to less water-consuming crops, to invest in watershed development activities, to change inefficient pumpsets and to adopt well spacing norms.


Author(s):  
R. Vinodh Kumar ◽  
M. Vakkil

The study was conducted to identify the most difficult topic in elementary teacher education first-year social science curriculum as perceived by the student-teachers by using survey research design. The study also investigated the underlying reasons responsible for the student-teachers' difficulties in learning different topics. 218 student-teachers were selected using convenience sampling technique from five District Institutes of Education and Training (DIET), in Tamil Nadu State (India) for the study. The instrument used for data collection was a checklist designed by the researchers to elicit information from the student-teachers. The data collected were analysed using frequencies and percentages. The results showed that the topic namely, 'Reading the Globe, Maps and Atlas' was perceived as the most difficult topic in social science curriculum. The results also showed that teaching the topic without using the maps, lack of previous knowledge about the maps, the existence of vague concepts, heavy content load, and lack of interest and motivation to learn map concepts were the main reasons responsible for the student-teachers' difficulties in learning the topic.


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