A study was carried out to estimate the extent of rubber area with high status of soil organic carbon (SOC) and soil depth greater than one meter to calculate the net savings by skipping chemical fertilizers in such holdings in the traditional rubber growing regions of Kerala and Kanyakumari district of Tamil Nadu using geo-spatial approach. Satellite-derived rubber plantation maps, SOC and soil depth maps were used for the present analysis. Thematic layers of SOC and soil depth were taken from the data base of Rubber Soil Information System (RubSIS) developed recently by Rubber Research Institute of India. The extent of rubber area with high soil OC status having a depth of more than one meter were delineated using spatial overlay analysis. Regions qualifying for this dual criteria were considered to estimate the net savings, including fertilizer cost and labour charges. Results indicated that in 1,61,911 ha of mature rubber area in Kerala and Kanyakumari district of Tamil Nadu, fertilizer application can be skipped for short periods which accounted for a net annual saving of Rs. 87 crores per year. District-wise interpretation revealed that net annual savings was the highest in Kottayam district (Rs. 27.4 crore per year) and in all other districts net annual savings would be below Rs.10 crores per year. Geo-spatial analysis was helpful in identifying mature rubber area where fertililizers can be skipped for short periods which could reduce the cultivation cost and avoid unnecessary pollution.

This paper investigates the effect of polybutadiene rubber content on the efficiency of stable free radical (4-hydroxy tempo, 4HT) assisted mechanical devulcanisation of NR/BR blends. Further, the effectiveness of this novel process in the real world is tested by the devulcanisation of commercial NR/BR blends like buffing dust obtained from pre-cured tyre tread and ground tyre rubber (GTR). Based on the minimum torque (ML) values recorded for devulcanised samples, which is indirectly related to the viscosity of the sample, it was observed that comparable level of devulcanisation can be achieved for NR/BR blends upon mechanical devulcanisation (control process) irrespective of the BR content in the blend. In 4HT assisted mechanically devulcanised samples, a higher per cent devulcanisation was indicated by further reduction in ML values. The revulcanisate tensile properties of the 4HT assisted devulcanised blends were significantly higher than the corresponding mechanically devulcanised samples whereas the positive influence of 4HT upon the tear strength of revulcanised samples significantly reduced with increase in BR content of the blend. The 4HT assisted devulcanisation of buffing dust and used rubber samples like GTR proposed the feasibility of stable free radical as an effective devulcanisation aid. The revulcanisate properties of the buffing dust and GTR devulcanised with the assistance of 4HT were higher than that obtained for the corresponding mechanically devulcanised sample. The revulcanisate properties of GTR were lower than that of buffing dust indicating the role BR content and the quality of sample (effect of ageing) used for devulcanisation upon the revulcanisate properties.

Different types of rubbers have different ageing properties. Service life of rubber products is determined by the differences in ageing properties of the rubbers used in the products and the conditions to which the products are exposed to during their service life. The present work is an attempt to predict the service life of products made up of nitrile rubber (NBR), ethylene propyle diene (EPDM) rubber and NR based on the Arrhenius theory. Logarithm of days in air to reduce the tensile strength to least serviceable level of 10 MPa for NBR and EPDM and 20 MPa for NR were plotted against 1/T where ‘T’ is the temperature in Kelvin scale. When the results were extrapolated to 1/T for room temperature (3.3 x 10-3), we got log days for room temperature as 7.5 for NBR. This indicates that the product made out of the formulation used can give a service life of 1808 days in air. In a similar way it was predicted that the service life of the NBR product of the formulation studied was only 992 days in sea water. Similarly the service life of EPDM and NR of the formulation used in the present study was estimated as 2208 days and 633 days, respectively in air, and that in sea water was estimated to be 854 days and 81 days, respectively.

Advances in genetics and genomics have led to the development of GM crops during the early nineties. Agricultural biotechnology is perhaps the single most significant technology that got wide acceptance after the green revolution. Agricultural biotechnology has obvious advantages in terms of higher yields, improved nutritive value, reduced pesticide consumption, enhanced stress tolerance of the crop etc. Though protocols are available for assessing the safety aspects of GM crops, the society at large is concerned about the safe use of such varieties. Cultivation of GM crops increased tremendously from 1996 onwards. Now GM crops are cultivated in a total area of 189.8 million hectares in 26 different countries. In terms of global area under biotech crops, the US occupies first position with an area of 75 mha, followed by Brazil (50.2 mha), Argentina (23.6 mha), Canada (13.1 mha) and India (11.4 mha). The major GM crops now cultivated globally include soybean, maize, cotton and canola. Still more GM crops such as rice and banana are in the pipeline under different stages of field testing in many countries. The only commercially grown GM crop in India is Bt cotton. India became the largest producer and exporter of cotton by the adoption of Bt technology and has the world’s fifth largest area with a single GM crop. Though several countries, particularly in Europe restrict GM crop cultivation, import of the same as food/feed is permitted. It is expected that countries such as China might come up with more GM crops and will become a major player in agricultural biotechnology in near future.