186 research outputs found

    Algal carbon sequestration in rice soil eco system

    Get PDF
    This Technical brief is a short summary of the results obtained from the field experiments conducted at Anbhil Dharmalingam Agricultural College and Research Institute, Trichy to study the algal succession in rice soil besides quantifying the biomass generation potential of different Cyanobacterial species, namely Nostoc, Anabaena, Westiellopsis and Plectonema, isolated from Cauvery basin as a part of the ClimaRice project during the summer season 2010. Higher Nostoc abundance coincided with lower of other two genera. Anabaena was the first cyanobacterial species to develop in field two weeks after transplantation of rice. Many rice-field soils not only contain a high density of cyanobacteria, but possess visually obvious growths of cyanobacteria at (or floating above) the surface, during most part of the growth stages. Cyanobacteria which multiplies easily in rice field ecosystem has great potential as biofertilizer, also it could be employed for sequestering atmospheric carbon in paddy soils

    Indian Finfish Exports – An Analysis of Export Performance and Revealed Comparative Advantage

    Get PDF
    The export of finfish from India has been rising over the past few years and in 2006-07 it contributed almost 44 per cent of the total marine products exported from the country in quantity terms. However in value terms its contribution is only 16 per cent, indicating low unit value realization of the products. This paper has analysed the export performance and has studied the revealed comparative advantage of finfish export from India for the period 2001 to 2005. The finfish exports from India have not revealed any comparative advantage among the total marine products export in the period of study. The paper has suggested reviewing of the policy of finfish export, with a shift in emphasis to export of only high-value finfish and value-added low-value finfish.Agricultural and Food Policy,

    Analysis of coconut cultivars and hybrids using isozyme polymorphism

    Get PDF
    The coconut (Cocos nucifera L.) is one of the major oilseeds of India. In the present study, an attempt has been made to analyse coconut diversity using isozyme banding data. Cluster analysis was performed using the banding patterns obtained from polyacrylamide gel electrophoresis for 11 isozyme systems in 40 different coconut cultivars and six hybrids and their parents. The cultivars grouped mainly into six clusters. In case of hybrids and their parents, the hybrids clustered intermediate between parents

    Intrapopulation allelomorphism in tall and dwarf populations of the coconut

    Get PDF
    Six Dwarf and eight Tall types of coconut were used to study intrapopulation variation based on protein/isozyme polymorphism. Total soluble proteins and seven isozyme systems – peroxidase (PRX, EC 1.11.1.7), esterase (EST, EC 3.1), acid phosphatase (ACP, EC 3.1.3.2), malate dehydrogenase (MDH, EC 1.1.1.37), polyphenol oxidase (PPO, EC 1.14.18.), alcohol dehydrogenase (ADH, EC 1.1.1.1) and glutamate oxaloacetate transaminase (GOT, EC 2.6.1.1) were used for the study. Among Dwarfs, the highest enzyme polymorphism was observed in Gudanjali Dwarf, while Gangabondham Dwarf showed the lowest polymorphism. Of the eight Talls studied, Java Tall showed the highest isozyme polymorphism, while the lowest polymorphism was seen in SNRT. Overall, among seven isozyme systems, PPO showed the highest polymorphism, while ACP did not show any polymorphism. Differences in the allelic frequency were obtained even though there were no specific differences in the banding pattern of varieties

    Project Inception Report

    Get PDF
    publishedVersio

    Degree days and demography of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) on maize at different temperatures

    Get PDF
    The temperature has a direct effect on the activity of insect pests and their developmental rate. The increasing temperature could profoundly influence the population dynamics, life cycle, length of reproduction, fecundity, and longevity. In the present study, the impact of different temperatures (32, 33, 34, 35 and 36°C) on the degree days and population fitness of Spodoptera frugiperda (J. E. Smith) was evaluated under artificial conditions. The results showed that for S. frugiperda, an average of 690.38 degree days was required to complete the total life span. The total larval developmental time, pupal duration and adult longevity required 237.38, 184.47 and 228.10 degree days, respectively. The life history data of S. frugiperda were analysed by using TWOSEX-MSChart. An increase in temperature reduced the developmental time of S. frugiperda at age x and stage j. The highest reproductive value (vx) of S. frugiperda was obtained at 34°C (600 individuals per day) and was found to be reduced at a further increase in temperature of 35°C (260 individuals per day) and 36°C (120 individuals per day). These results signify the improved fitness of S. frugiperda with increasing temperature levels, and the degree days help to predict the development pattern of S. frugiperda based on heat accumulation

    The Impact of El Niño/Southern Oscillation on Hydrology and Rice Productivity in the Cauvery Basin, India: Application of the Soil and Water Assessment Tool

    Get PDF
    AbstractThis study was performed to further understanding of the variations in hydrology and rice crop productivity during different El Niño/Southern Oscillation (ENSO) events in the Cauvery River Basin of Tamil Nadu, India using the Soil and Water Assessment Tool (SWAT). The entire Cauvery Basin was divided into 301 sub-basins and further subdivided into 3,601 Hydrological Response Units (HRU). Based on the National Oceanic and Atmospheric Administration (NOAA) official website, information on El Niño (1972, 1982, 1987, 1991, 1997, 2002 and 2004) and La Niña (1970, 1971, 1973, 1974, 1975, 1988, 1998, 1999 and 2000) years were obtained. The SWAT model was continuously run from 1970 to 2008, and a composite for El Niño, La Niña and normal years was constructed to understand their influence on hydrology and rice crop productivity in the study area. From the analysis, it was clear that an El Niño episode is correlated with rainfall, hydrology and rice productivity in the Cauvery river basin. The validation of the SWAT model indicated the capability of SWAT to accurately predict stream flow and rice productivity. It was evident from the investigation that the quantum of rainfall was more during El Niño years with high inter-annual rainfall variability (809.3mm to 2,366mm) compared with La Niña and normal years. As a result, the soil water recharge, including percolation and soil water availability in the surface layers, was increased in the El Niño years. Simulated rice productivity over 39 years in the Cauvery Basin ranged between 1,137 and 7,865kgha−1 with a mean productivity of 3,955kgha−1. The coefficient of variation in rice productivity was higher during La Niña (21.4%) years compared with El Niño (14.7%) and normal years (14.6%). The mean rice productivity was increased in both El Niño and normal years, indicating the possibility of higher yields than those in La Niña years. An analysis of the hydrological data and rice productivity showed that the risk of failure was low during El Niño years compared with normal or La Niña years. This behavior could be utilized for forecasting rice crop productivity under different ENSO conditions and can provide information for policy makers when deciding on water allocation and import / export policies

    Intrapopulation allelomorphism in tall and dwarf populations of the coconut

    Get PDF
    Six Dwarf and eight Tall types of coconut were used to study intrapopulation variation based on protein/isozyme polymorphism. Total soluble proteins and seven isozyme systems – peroxidase (PRX, EC 1.11.1.7), esterase (EST, EC 3.1), acid phosphatase (ACP, EC 3.1.3.2), malate dehydrogenase (MDH, EC 1.1.1.37), polyphenol oxidase (PPO, EC 1.14.18.), alcohol dehydrogenase (ADH, EC 1.1.1.1) and glutamate oxaloacetate transaminase (GOT, EC 2.6.1.1) were used for the study. Among Dwarfs, the highest enzyme polymorphism was observed in Gudanjali Dwarf, while Gangabondham Dwarf showed the lowest polymorphism. Of the eight Talls studied, Java Tall showed the highest isozyme polymorphism, while the lowest polymorphism was seen in SNRT. Overall, among seven isozyme systems, PPO showed the highest polymorphism, while ACP did not show any polymorphism. Differences in the allelic frequency were obtained even though there were no specific differences in the banding pattern of varieties

    Studies on the relationship of weather on Fall armyworm damage in maize (Zea mays L.) under different growing environments

    Get PDF
    Fall armyworm is a recently occurring invasive pest in India, the most important defoliator causing drastic damage to maize production. Hence, the present study aimed to understand the temporal infestation level of Fall armyworms on maize (Zea mays L.) with weather patterns. Field experiments were conducted during Summer (February-May) and Rainy seasons, 2022 (August-December) at Agro Climate Research Centre, Tamil Nadu Agricultural University, Coimbatore. Three different growing environments (GE1, GE2 and GE3) were created by providing staggered sowing. Regression models were developed for per cent leaf damage against three-days lagged (LT3) and seven-day lagged (LT7) weather variables. Results showed that irrespective of growing environments, weather variables showed negative correlation (Tmax: r = -0.57, -0.81*, -0.31; SSH: -0.30, -0.48, -0.39; Tmean: -0.49, -0.23, -0.30; and SR: -0.48, -0.94*, -0.40) during summer season whereas same variables (i.e Tmax =0.62*, 0.41, 0.33; SSH = 0.09, 0.68*, 0.24; Tmean = 0.29, 0.32, 0.44; and SR=0.13, 0 .67*, 0.26 ) showed a positive correlation with PLD. Rainfall exhibits positive relation (0.06, 0.54, 0.53) and negative correlation (-0.64*, -0.10, -0.02) during summer and rainy season, respectively. Among the regression models, LT7 model had higher R2 (0.65 and 0.76) than LT3 (0.57 and 0.68) during summer and rainy seasons, respectively. These models had good regression values of 0.56 and 0.70 during Rainy and Summer, respectively. It was concluded that Tmax (32.9 °C), Tmin (23.7 °C), Tmean (28.3 °C), RH-I (85.6%), RH-II (56.4%), SSH (4.1), SR (274.6 cal cm-2 m-2), afternoon cloud cover (4.8 okta) and weekly total rainfall (10.2 mm) were very conducive for the greater leaf damage
    corecore