Agro-climatic Zone Of Tamil Nadu Research Articles

Performance of Coleus (Coleus forskohlii) in Different Agro-climatic Zones of Tamil Nadu, India

A study was undertaken to characterize the Coleus-growing soils in different agro-climatic zones of Tamil Nadu to identify the yield limiting soil properties and management. Thesoil characteristics were rated for their quality as low, medium and high of three zones to assess. The horizon-wise soil samples from Typifying soil profiles and surface samples were collected from representing agro-climatic zones and soils were analysed. Soils were shallow to deep, well to somewhat poorly drained, dark brown to dark reddish brown in colour. The soils were sandy clay loam to sandy clay in texture and the clay content ranged from 28 to 45% being highest in Muthur soils. The organic carbon in soils ranged from 0.30 to 0.90% and cation exchange capacity from 10.2 (Rajapatty soils) to 22.8 cmol (p+) kg-1 (Andipudur soils). Soils were low in available nitrogen, low to medium in available phosphorus and potassium. DTPA-extractable micro nutrients were sufficient in all the zones. Coleus yields were significantly correlated with available phosphorus, potassium and manganese.

Optimization of Irrigation and Fertigation Scheduling for Sustainable Sugarcane Initiative (SSI) through Subsurface Drip Irrigation in Western Zone of Tamil Nadu

Sustainable Sugarcane Initiative (SSI) under Sub Surface Drip Irrigation (SSDI) is gaining momentum among the farmers because of more output with less input. Even though the benefits of SSI under SSDI are realized by farmers, development of optimal irrigation and fertigation schedule is need of the hour for Western Agro-climatic zone of Tamil Nadu. Field trials were carried out at Agricultural Research Station, Bhavanisagar from 2014 to 2017 to develop an optimal irrigation and fertigation schedule for SSI for Western Agro-climatic zone. The experiment was taken in a randomized block design with three replications. The experiment consisted of eight treatments of which six treatments comprised of SSDI with three irrigation regimes of 100, 80 and 60 percent pan evaporation and two fertigation levels of 100 and 75 percent of recommended N & K and two treatments in surface drip irrigation (SDI) with 100 percent pan evaporation (PE) + 100 percent RD and 100 percent PE + 75 percent RD of N&K through fertigation. The results of this study revealed that SSDI with 60 per cent PE + 100 per cent RD of N&K through fertigation recorded lower water use (1004 mm) and higher WUE (113 kg/ha-mm). However, significantly higher and comparable yield of sugarcane (148 t/ha) was recorded in SSDI with 100 per cent PE + 100 per cent RD of N&K through fertigation and surface drip irrigation with 100 per cent PE + 100 per cent RD of N&K through fertigation. The net return (Rs. 2,09,405 per ha) and B:C ratio (2.6) was higher in SSDI with 100per cent PE + 100 per cent RD of N&K through fertigation treatment.

Cross Sectional Study on Bovine Tuberculosis Status in the Selected North-Eastern Agro-Climatic Zone of Tamil Nadu

A cross sectional study was conducted to determine the dynamic prevalence of bovine tuberculosis amongst bovine using single intra dermal cervical comparable test (SICCT or CIDT) in North-Eastern agro-climatic zone of Tamil Nadu. In the present study, Out of 1119 blood samples tested from four selected districts of North-Eastern agro-climatic zone of Tamil Nadu, the overall prevalence of M. bovis infection in North-Eastern agro-climatic zones of Tamil Nadu was found to be 8.46 per cent by CIDT and highest prevalence was noticed in Vellore (10.86%) district followed by Kancheepuram (8.20%), Thiruvallur (7.92%) and Chennai (6.86%) districts, which shows the potential to increase the incidence as well as prevalence of the disease since the “test and slaughter” or “culling policy” are yet to be strengthened intensively or warranting the calf-hood immunization against tuberculosis.

Influence of weather on the parasitoid catches in three rice growing agroclimatic zones of Tamil Nadu

Influence of weather on the parasitoid catches in three rice growing agroclimatic zones of Tamil Nadu

Impact of livestock production on poverty - evidence from rural Tamil Nadu*

The present study was undertaken in rural Tamil Nadu to quantify the impact of livestock production on poverty using randomly selected 540 sample respondents. The data were collected through personal interview using pretested interview schedules from sample respondents undergoing various occupations in the six districts covering four agro-climatic zones of Tamil Nadu. The per capita income function of households was fitted to explore the impact of livestock production on poverty. The results implied that the value of assets, education, employment in mandays, livestock occupation had a significant positive impact on the per capita income in contrast to the variables, viz. family size, family dependency ratio and illiteracy, which had negative impact. The per capita income with and without the particular occupation was estimated using the concerned co-efficients. Further, the poverty ratios were worked out in presence of an occupation and in absence of an occupation. The poverty indices were found to be higher for the income with occupation, when compared to the income without occupation for all the chosen occupations, except agricultural labourers. It could be concluded that the presence of agricultural labourer occupation increased the head count ratio (P0) by 0.0370, poverty gap index (P1) by 0.0208, poverty severity index (P2) by 0.0125 and the Watts index (W) by 0.0317. Among all the occupations, the presence of livestock farming decreased the poverty indices by the greatest extent (0.1852 of P0, 0.1002 of P1, 0.0593 of P2, and 0.1562 of W).). Following livestock, fishing had the greater potential of poverty reduction with the reduction values of 0.1852 (P0), 0.0844 (P1), 0.0492 (P2) and 0.1306 (W). Further, it could be revealed that the presence of livestock occupation, decreased the exit time for poverty by 5.22 years and it was 4.35 years for fishing occupation, 3.60 years for non-farm occupation and 2.05 years for cropping activity. Based on the results of the study, it could be concluded that the any poverty alleviation programme should comprise a livestock component.

Optimum livestock holding for exit out of poverty: A comparative analysis in rural Tamil Nadu

An attempt was made to assess the income generating capacity of selected livestock species reared by resource poor rural farmers and to estimate minimum livestock holding required to be reared by the households to escape out of poverty in rural Tamil Nadu. The data were collected through personal interview using pre-tested interview schedule from 213 livestock farmers from the six districts covering four agro-climatic zones of Tamil Nadu. Economics of cattle, buffalo, sheep and goat farming were worked out in order to estimate and compare the income generated from various livestock enterprises. The monthly income earned by the sample respondents was calculated to be ` 941.52/cattle, ` 932.72/buffalo, ` 125.91/sheep and ` 140.52/goat. Further, the study revealed that a household could tide over the poverty line without any other income source, if they rear a minimum of about 6 cattle (5.32 cattle) or 6 buffaloes (5.37 buffaloes) or 40 sheep (39.79 sheep) or 36 goat (35.65 goat). The present findings might be considered while implementing any poverty alleviation programmes with livestock component. Depending upon the locality and resources availability, suitable livestock species might be recommended to lift the poor from poverty trap and to sustain them with stable income.

Validation of Soil Test and Yield Target Based Balanced Fertilizer Prescription Model for Rainfed Maize on Inceptisol

Soil Test Crop Response based fertilizer prescription equations for desired yield target of rainfed maize were developed under Integrated Plant Nutrition System (STCR-IPNS) on Irugur soil series (Typic Ustropept) of Tamil Nadu. On farm testing of fertilizer prescription equations are essential to demonstrate the effectiveness of technology delivery to the stake holders in need. The present study was undertaken to evaluate the targeted yield model through field experiments at six locations in Dindigul district, Western Zone of Tamil Nadu. The treatments included control, blanket recommendation, soil test crop response (STCR) based fertilizer dose for the yield targets of 4.0 to 6.0 t ha-1 , STCR-IPNS based fertilizer dose for the yield targets of 4.0 to 6.0 t ha-1 and farmer’s practice. In all the six locations, the per cent achievement of the targeted yield was within  10 per cent variation proving the validity of the equations for prescribing integrated fertilizer doses for rainfed maize. The highest mean grain yield was recorded in STCR-IPNS – 6.0 t ha-1 (5013 kg ha-1 ) recording an increase of 52.2 per cent over blanket recommendation. The highest per cent achievement, response ratio and B:C ratio of 97.2,17.47 and 2.28, respectively were recorded in the yield target of 5.0 t ha-1 under STCR-IPNS. The post-harvest soil available NPK indicated the build up and maintenance of soil fertility due to soil test based fertilizer recommendation under IPNS. The fertilizer prescription equations developed for rainfed maize under IPNS can be recommended for red non calcareous soils of Tamil Nadu for achieving the yield target of 5.0 t ha-1 with sustained soil fertility and it can be extrapolated to other agro-climatic zones of Tamil Nadu on similar and allied soil types.

Molybdenum fertilization effect on nodulation, yield and quality of green gram grown in the soils of southern agro-climatic zone of Tamil Nadu, India

A pot experiment was conducted under natural condition with green gram (cultivar CO 6) using twenty bulk soil samples collected from major soil series of Southern agro–climatic zone of Tamil Nadu. Application of graded levels of molybdenum (Mo) at 0, 0.025, 0.050, 0.075 and 0.1 mg kg<sup>−1</sup> positively influenced the yield, nodulation characteristics and nutritional quality of green gram crop. The highest number of nodules, dry weight nodules per plant, nodule N concentration and chlorophyll content of leaves were registered at 0.075 mg kg<sup>−1</sup> level. Similarly, the seed and stover yield, uptake of N, P, K and Mo by green gram were also increased with molybdenum application up to 0.075 mg kg<sup>−1</sup> level beyond which they declined. However, the amount of protein in seed significantly increased with increasing levels of Mo up to 0.1 mg kg<sup>−1</sup> level in different soils. Hence, Mo application not only increased the yield but also enhanced the nutritional quality of green gram through effective nodulation.

Immunoassay‐based Techniques for Early and Specific Detection of Latent Postharvest Anthracnose in Mango

AbstractThe postharvest anthracnose pathogen Colletotrichum gloeosporioides inciting latent or quiescent infection of mango was detected in early stages using immunoassay methods. Twenty‐five pathotypes isolated from different agroclimatic zones of Tamil Nadu, Karnataka and Pondicherry, India, revealed the variation in protein profile analysis (SDS‐PAGE). The polyclonal antibodies (PCA) were raised against the unfractioned mycelial protein (UMP) and a 40‐kDa polypeptide present in all pathotypes. Standardization of antigen and antiserum dilutions revealed that an antigen dilution of 1 : 200 (protein concentration of 20 μg/ml) and antiserum dilution of 1 : 100 (protein concentration of 40 μg/ml raised against UMP) and 1 : 200 (protein concentration of 20 μg/ml raised against 40 kDa polypeptide) was found to be optimum for the detection of anthracnose pathogen. Both antisera detected the C. gloeosporioides antigen in enzyme‐linked immunosorbent assays (ELISAs), dot immunobinding assays (DIBAs) and Western blots. The specificity in reaction was compared by isolating other Colletotrichum spp. from various hosts viz., C. lindemuthianum (beans), C. falcatum (sugarcane), C. musae (banana), C. capsici (chillies) and Botryodiplodia theobromae (mango). The antisera generated against UMP revealed the cross‐reaction with other host isolates and mango stem end rot pathogen (B. theobromae). The PCA raised against 40‐kDa polypeptide exhibited the specific reaction with C. gloeosporioides isolates in all the immunoassay techniques. By utilizing both PCA, the presence of latent infection was observed in healthy‐looking leaves, flowers and fruits in orchard conditions. The fruit tissues recorded high absorbance values followed by flowers and leaves in all the detection methods. The ELISA technique was also useful in assessing the pathogen inoculum at various biocontrol formulations sprayed mango trees under field conditions. The fluorescent pseudomonad strains mixture (KFP1 + FP7) amended with chitin sprayed at 30‐day intervals revealed the significant reduction in pathogen load than other formulations and unsprayed control.

Yield variability in rainfed crops as influenced by climate variables

Purpose – This paper aims to explore the impact of climate change on yields and yield variances in major rainfed crops and measure possible changes in yields under projected climate changes in different agro-climatic zones of Tamil Nadu, India. Although many empirical studies report the influence of climate change on crop yield, only few address the effect on yield variances. Even in such cases, the reported yield variances were obtained through simulation studies rather than from actual observations. In this context, the present study analyzes the impact of climate change on crops yield and yield variance using the observed yields. Design/methodology/approach – The Just-Pope yield function (1978) is used to analyze the impact of climate change on mean yield and variance. The estimated coefficient from Just-Pope yield function and the projected climatic data for the year 2030 are incorporated to capture the projected changes in crop yield and variances. Findings – By the year 2030, the yield of pulses is estimated to decline in all the zones (Northeast, Northwest, Western, Cauvery delta, South and Southern zones), with significant declines in the Northeast zone (6.07 per cent), Cauvery delta zone (3.55 per cent) and South zone (3.54 per cent). Sorghum yield may suffer more in Western zone (2.63 per cent), Southern zone (1.92 per cent) and Northeast zone (1.62 per cent). Moreover, the yield of spiked millet is more likely to decrease in the Southern zone (1.39 per cent), Northeast zone (1.21 per cent) and Cauvery delta zone (0.24 per cent), and the yield of cotton may also decline in the Northeast zone (12.99 per cent), Northwest zone (8.05 per cent) and Western zone (2.10 per cent) of Tamil Nadu, India. Originality/value – The study recommends introducing appropriate crop insurance policies to address possible financial losses to the farmers. Prioritizing area-specific stress-tolerant crop varieties without complementing yield would sustain crops cultivation further.

Facets of migratory sheep production system in southern Tamil Nadu

A study was conducted to analyze the migratory sheep production system in southern agro-climatic zone of Tamil Nadu. A total of 100 migratory sheep farmers were selected randomly in the study location. The overall mean flock size was 228.13±11.46 with a sex ratio of 1:24. Amigratory sheep flock was comprised of 2.74% breeding rams, 66.19% breeding ewes, 0.56% young males, 14.79% young females, 5.70% male lambs and 8.02% female lambs. The mean duration of penning in agricultural lands and coconut groves was 8.55±0.07 months in a year. The mean grazing time and distance covered were 10.59±0.05 h and 5.34±0.12 km/day in summer and 9.05±0.08 h and 3.70±0.07 Km/day in other seasons, respectively.

Validation of soil test and yield target based fertilizer prescription model for wheat on inceptisol

Soil test crop response (STCR) based fertilizer prescription for desired yield target of wheat was developed under Integrated Plant Nutrition System (STCR-IPNS) on Periyanaickepalayam soil series (Vertic Ustropept) of Tamil Nadu. On-farm testing of fertilizer prescription equations are essential to demonstrate the effectiveness of technology delivery to the stake holders in need. The present study was undertaken in six locations to evaluate the model through field experiments in Western Zone of Tamil Nadu. The treatments included control, blanket recommendation, soil test crop response (STCR) based fertilizer dose for an yield target of 3.0 and 4.0 t/ha, STCR-IPNS based fertilizer dose for an yield target of 3.0 and 4.0 t/ha and farmer's practice. Based on the initial soil test values of available N, P and K and the quantities of N, P and K contributed through farm yard manure (FYM), fertilizer doses were calculated and applied for STCR and STCR-IPNS treatments for the respective yield targets. The treatments were imposed and cultivation practices were carried out periodically and the grain yield was recorded at harvest. Using the data on grain yield and fertilizer doses applied, per cent achievement and response ratio (RR) were worked out. Post-harvest soil samples were collected and analyzed for available N, P and K status. The results of the experiments indicated that in all the six locations, the per cent achievement of the targeted yield was within±10% variation proving the validity of the equations for prescribing integrated fertilizer doses for wheat. The highest mean per cent achievement was recorded in the yield target of 4.0 t/ha (101.2) under STCR-IPNS followed by STCR-NPK alone 4.0 t/ha. The highest mean yield was recorded in STCR-IPNS–4.0 t/ha (4047 kg/ha) recording an increase of 62.1% over blanket recommendation. Among the treatments, STCR-IPNS recorded relatively higher RR than other treatments and the highest mean RR of 6.90 kg/kg was recorded under STCR-IPNS 4.0 t/ha. The highest benefit: cost ratio (1.81) was also recorded in STCR-IPNS 4.0 t/ha. The post-harvest soil available NPK indicated the build up and maintenance of soil fertility due to soil test based fertilizer recommendation under IPNS. The fertilizer prescription equations developed for wheat under IPNS can be recommended for mixed black calcareous soils of Tamil Nadu (Vertic Ustropept) for achieving an yield target of 4.0 t/ha with sustained soil fertility and it can be extrapolated to other agro-climatic zones of Tamil Nadu on similar and allied soil types.

Assessment of SOC Stock, Their Changes Overtime and Prediction of SOC Stock Using Roth-C Model for Benchmark Soils of Different Agro-climatic Zones of Tamil Nadu

A study was conducted in different agroclimatic zones of Tamil Nadu with the objective of assessment of Soil Organic Carbon (SOC) stock and its changes overtime, prediction of SOC stock under existing and alternate cropping pattern using Roth C model. Fifteen benchmark soils were selected in different agroclimatic zones of Tamil Nadu based on their land use and areal extent to assess SOC level and its changes overtime. Results revealed that, during 1997 and 2007 SOC was higher in forest ecosystem of pedon 15 (Ooty series) and in pedon 14 (Pechiparai series) of horticultural land use. Among seven agroclimatic zones of Tamil Nadu soil series in five agroclimatic zones viz., Periyanaickenpalayam series (Western zone), Peelamedu series (Southern zone), Vallam series (North eastern zone), Vannappatti series (North western zone) and Padugai series (Cauvery delta zone) were selected to predict SOC stock for the year 2025 and 2050 except hilly and high rainfall zone due to high organic carbon content in these agroclimatic zones. Results showed that, among the soil series selected for the study, Vannappatti and Padugai series registered the highest Total Organic Carbon (TOC), Biomass Carbon (BIO) and Humified Organic Carbon (HUM) under existing cropping pattern while Periyanaickenpalayam, Peelamedu and Vallam series had high TOC, BIO and HUM under alternate cropping pattern. Among five selected soil series, Periyanaickenpalayam, Peelamedu and Padugai series recorded 7.5 g kg-1 TOC during 2025 and 2018, 2100 and 2035, 2013 and 2014 under existing and alternate cropping pattern respectively.

Multiple linear regression model for forecasting Bluetongue disease outbreak in sheep of North-west agroclimatic zone of Tamil Nadu, India

Aim: A study was undertaken to develop a forecasting model for predicting bluetongue outbreaks in North-west agroclimatic zone of Tamil Nadu, India. Materials and Methods: Eleven bluetongue outbreaks were characterised by active and passive surveillances for a period of twelve years and used in this study. Meteorological data comprising of maximum and minimum temperatures, relative humidity, rainfall and wind speed were collected and used as the multiple predictor variables in the multiple liner regression model. Results: A multiple liner regression model was developed for the North-west zone of Tamil Nadu. Values of the dependant variables were less than or greater than one, and indicated remote or greater chances of bluetongue outbreaks respectively. The monthly mean maximum and minimum temperatures, relative humidity at 8.30 h and at 17.00 h IST, wind speed, and monthly total rainfall of 29.1 - 31.0°C, 20.1 - 22.0°C, 80.1 - 85.0%, 65.1 - 70.0%, 3.1 - 5.0 km/h and < 200 mm respectively, were identified as the ideal climatic conditions for increased numbers of bluetongue outbreaks in this zone. Conclusion: Based on the values obtained from the prediction model, stake holders can be warned timely through the media to institute suitable prophylactic measures against bluetongue, to avoid economic losses due to disease.

Exploring the Psychological Antecedents of Attitude towards Indigenous Wetland Practices

A study was conducted in the North eastern agro-climatic zone of Tamil Nadu, India to analyze the possible impact of the psychological antecedents of attitude towards Indigenous Wetland Practices(IWPs) among the farming community. Two hundred and nine farmers were selected at random from ten blocks in three districts of the state. Their psychological characteristics and attitude towards IWPs were assessed. The mean attitude score and the mean attitude index were analysed. The highest variable index was found in the case of Progressivism and Traditionalism, followed by Self-Reliance. Environmental orientation and Decision making ability had a positive and highly significant relationship while Scientific Orientation had a negative and highly significant relationship with attitude towards Indigenous Wetland Practices.

Breed characteristics of Mecheri sheep

SummaryThis study was carried out on 2 309 households in 60 villages with the objective of documenting the performance of Mecheri sheep in their native environment. The study revealed that Mecheri sheep were distributed in Salem, Erode, Karur, Namakkal and parts of Dharmapuri districts of Tamil Nadu. This tract lies in the north-western agro-climatic zone of Tamil Nadu and the climate is generally hot, semi-arid and tropical in nature.The average flock size of Mecheri sheep was 24, of which, there were 1 ram, 17 ewes and 6 lambs. Mecheri sheep of medium size with a compact body and covered with short hairs, which are not shorn. They are light brown in colour. Their profile reveals a slightly Roman nose. Both males and females are polled. The pooled means for height at withers, chest girth and body length at above 24 months of age were 67±0.4, 74±0.4 and 66±0.4 cm, respectively. The body weight of the animals at birth 3, 6, 9 and 12 months of age was 2.82±0.01, 10.9±0.1, 15.6±0.1, 17.6±0.2 and 21.1±0.1, kg respectively. The dressing percentage of males and females was 54.4±0.4 and 51.8±0.5, respectively. Average ages at first oestrus, mating and lambing were 12.1±0.1, 12.4±0.1 and 17.4±0.1 months, respectively. The average lambing interval was 226±0.7 days and the average litter size was one.

Influence of production environment on seed quality in rice (Oryza sativa L.0 hybrid ADTRH1

Seed samples of rice hybrid ADTRH 1 collected from 25 locations spread over in two different agro-climatic zones of Tamil Nadu revealed significant variations in various seed quality components viz. physical (purity, ODV, split husk seeds and 100 seed weight), physiological (seed germination, speed of germination, dry matter production, vigour index and electrical conductivity of seed leachate) and health. Among the centres of hybrid rice seed production, Coimbatore and Bhavanisagar centres in Western Zone of Tamil Nadu were adjudged as the best and suitable places for hybrid rice seed production.

Screening the resistance of different seed sources of Azadirachta indica for acidity and alkalinity tolerance

To screen the resistance towards alkalinity and acidity, the seeds of Azadirachta indica collected from six seed sources, comprising six agro-climatic zones of Tamil Nadu were utilized. The seeds were sown between paper towel medium. The solutions of pH ranging from 1 to 12 were employed as treatments to dip the paper towels sown with seeds from different seed sources. Water served as control. The result of the experiment proved that Azadirachta indica has the tolerance to certain level of acidity (up to pH 4) and alkalinity (up to pH 8). The species is not capable of germinating in a pH lesser than 4 or more than 8. Among the seed sources, significant variation has been exhibited. The seeds collected from Southern zone seed source exhibited good potential to tolerate a pH ranging from 4 to 8. Seeds collected from Cauvery-delta zone seed source were found to be more susceptible to extremes of pH.

Weed management in rainfed cowpea (Vigna unguiculata) and greengram (Phaseolus radiatus) under North-Western Agroclimatic Zone of Tamil Nadu

In a 2-year field experiment an application of herbicide either pendimethalin or fluchloralin 3 days after sowing was found effective in controlling weeds and recorded lower weed population and dry matter of weed. Application of pendimethalin (1.5 or 2.0 litreslha) or fluchloralin (1.0 or 1.5 litreslha) at 3 days + 1 hand-weeding at 30 days caused significant reduction in weed population and weed dry metter and marked increase in crop yield and were comparable with hand-weeding twice at 15 and 30 days in rainfed cowpea [Vigna unguiculata (L.) Walp.] and greengram (Phaseolus radiatus L.). In places where labour availability - was not a problem hand-weeding twice at 15 and 30 days could fetch higher net returns in rainfed cowpea and greengram under North-Western Agroclimatic Zone of Tamil Nadu.

Response of farming studies in rainfed finger millet (Eleusine coracana) under erratic monsoon conditions of north western agroclimatic zone of Tamil Nadu

An experiment was conducted during the rainy season or kharif of 1999 and 2000 to study the effect of sowing time with different varieties and moisture conservation practices on growth and yield of rainfed finger millet [Eleusine coracana (L.) Gaertn.]. In both the years the dry spell occurred for 15 to 30 days after normal sowing time for rainfed finger millet. The long duration Paiyur 1 finger millet (1 10 days) sown during normal sowing time recorded low mean grain yield (1,594 kglha). But when sowing was done after initial dry spell with DPI 201 1 ( Dharmapuri ) finger millet (95 days) a good grain yield (2,415 kglha) was obtained. Anlong the management practices studied, incorporation of composted choir pith along with recommended inorganic fertilizers recorded the highest mean grain yield (2,222 kglha), followed by the treatment of soil mulch with blade harrow with recommended inorganic fertilizers (2,100 kglha). Plant height, number of productive tillers, net income and benefit : cost ratio showed similar trend as that of gain yield.