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Conventionally, dye-exclusion test for determining cell viability has been restricted only for cells in suspension in tissue culture. In this paper, salivary gland of Chironomus has been proposed as a simple tissue model system where dye-exclusion test can be reliably employed for the intact gland. We have compared suitability of commonly used vital dyes and nigrosin was found suitable for the salivary gland cells. Biochemical tests using tetrazolium salts are also commonly used for determining quantitative indices of cell viability in metabolically active cells. Ours is the first attempt to extend the same technique for the whole tissue. We standardized the conditions and prepared a protocol for MTT-based colorimetric assay suitable for the salivary gland of Chironomus. A strong correlation (r2 = 0.9893) was obtained where increasing O.D. correlated linearly with the number of live glands. We concluded that nigrosin dye-exclusion and MTT metabolic inclusion assays are suitable methods for the viability test of metabolically active intact salivary gland of Chironomus which can serve as a potential model for the assessment of cytotoxicity in future.

To assess the deficiency in the activity of the monsoon over India during the season, an index for the country based on the percentage area with a specified percentage seasonal rainfall deficiency and termed the Monsoon Deficiency Index (MDI), has been utilized. The statistical properties of the MDI series for the period 1871–1978 have been examined. The series which can be taken to be homogeneous and random has a high variability. MDI is generally not observed to persist at a high level; a high value is invariably followed by a low value. The deficiency over the country is considered as largescale and is termed as monsoon failure when the MDI value equals or exceeds the nineth decile viz. 40, of the mixed gamma distribution fitted to the MDI series. Using this criterion, the years of monsoon failure have been identified. The monsoon failures are found to occur randomly. The effect of monsoon deficiency on the Indian economy has been assessed.

To assess the excess in the activity of the summer monsoon (June to September) over India during the period 1871 to 1978, an index based on the percentage area with a specified percentage seasonal rainfall excess and termed as the Monsoon Excess Index (MEI) has been used. On examination of MEI series it is found that it is homogeneous and random and has a high variability. The distribution of MEI is positively skewed and Gamma probability model is observed to be a good fit to the series. Considering the year in which the MEI value exceeds the nineth decile, i.e. 35, of the Gamma distribution fitted to the MEI series, as year of large-scale excess over India, such years have been identified during the period 1871–1978. There are ten such years. These excess years are found to be randomly distributed in time.

Abstract: The associations between strong to moderate El Nino events and the all-India and subdivisional summer monsoon rainfall is examined for the period 1871 to 1978. The significance of the association is assessed by applying the Chi-square test to the contingency table. The analysis indicates that during 22 El Nino years the Indian monsoon rainfall was mostly below normal over most parts of the country. However, the association between El Nino and deficient rainfall or drought is statistically significant over the subdivisions west of longitude 80E and north of 12N. During the five strong El Nino years—1877, 1899, 1911, 1918, and 1972—many areas of India suffered large rainfall deficiencies and severe droughts. There are four moderate El Nino years—1887, 1914, 1953, and 1976—when the suffering was marginal. The relationship between El Nino and the Indian monsoon rainfall is expected to be useful in forecasting large-scale anomalies in the monsoon over India.

The Indian summer monsoon rainfall is known to have considerable spatial variability, which imposes some limitations on the all-India mean widely used at present. To prepare a spatially coherent monsoon rainfall series for the largest possible area, fourteen subdivisions covering the northwestern and central parts of India (about 55% of the total area of the country), having similar rainfall characteristics and associations with regional/global circulation parameters are merged and their area-weighted means computed, to form monthly and seasonal Homogeneous Indian Monsoon (HIM) rainfall series for the period 1871–1990. This paper includes a listing of monthly and seasonal rainfall of HIM region. HIM rainfall series has been statistically analysed to understand its characteristics, variability and teleconnections for long-range prediction.

The relationship between the all-India summer monsoon rainfall and surface/upper air (850, 700, 500 and 200 mb levels) temperatures over the Indian region and its spatial and temporal characteristics have been examined to obtain a useful predictor for the monsoon rainfall. The data series of all-India and subdivisional summer monsoon rainfall and various seasonal air temperatures at 73 surface observatories and 9 radiosonde stations (1951–1980) have been used in the analysis. The Correlation Coefficients (CCs) between all-India monsoon rainfall and seasonal surface air temperatures with different lags relative to the monsoon season indicate a systematic relationship.

To assess the excess in the activity of the summer monsoon (June to September) over India during the period 1871 to 1978, an index based on the percentage area with a specified percentage seasonal rainfall excess and termed as the Monsoon Excess Index (MEI) has been used. On examination of MEI series it is found that it is homogeneous and random and has a high variability. The distribution of MEI is positively skewed and Gamma probability model is observed to be a good fit to the series. Considering the year in which the MEI value exceeds the nineth decile, i.e. 35, of the Gamma distribution fitted to the MEI series, as year of large-scale excess over India, such years have been identified during the period 1871–1978. There are ten such years. These excess years are found to be randomly distributed in time.

To assess the deficiency in the activity of the monsoon over India during the season, an index for the country based on the percentage area with a specified percentage seasonal rainfall deficiency and termed the Monsoon Deficiency Index (MDI), has been utilized. The statistical properties of the MDI series for the period 1871–1978 have been examined. The series which can be taken to be homogeneous and random has a high variability. MDI is generally not observed to persist at a high level; a high value is invariably followed by a low value. The deficiency over the country is considered as largescale and is termed as monsoon failure when the MDI value equals or exceeds the nineth decile viz. 40, of the mixed gamma distribution fitted to the MDI series. Using this criterion, the years of monsoon failure have been identified. The monsoon failures are found to occur randomly. The effect of monsoon deficiency on the Indian economy has been assessed.

On the basis of all available record, a series of summer monsoon rainfall of India as a whole has been obtained for the period 1841 to 1977. Years of bad monsoon over the country have been identified. It has been shown that the occurrences of bad monsoon years are random events in the time continuum and that the number of bad monson years in a five-year period is distributed according to the Poisson probability law. A bad monsoon year dislocates the country's economy. To avoid this the country may provide adequate funds keeping in view the probability of getting bad monsson year(s) in a five-year period.

Data from 306 stations in India, for the 70 years (1901–70) of summer (June–September) monsoonal rainfall, are grouped into 32 sub-regions. Extreme event theory is used to analyse the return periods of extreme rainfall deficits within each of these sub-regions, using the log-Pearson type III frequency distribution in a spatial rather than a temporal context. The resultant estimates for 2, 5 and 10 year return periods are compared with the patterns derived from the Gaussian frequency distribution applied to the 306 stations individually; the 50 and 100 year return period estimates are also considered.

Analysis of summer monsoon (June to September) rainfall series of 29 subdivisions based on a fixed number of raingauges (306 stations) has been made for the 108-year period 1871–1978 for interannual and long-term variability of the rainfall. Statistical tests show that the rainfall series of 29 sub-divisions are homogeneous, Gaussian-distributed and do not contain any persistence. The highest and the lowest normal rainfall of 284 and 26 cm are observed over coastal Karnataka and west Rajasthan sub-divisions respectively. The interannual variability (range) varies over different sub-divisions, the lowest being 55 and the highest 231% of the normal rainfall, for south Assam and Saurashtra and Kutch sub-divisions respectively. High spatial coherency is observed between neighbouring sub-divisions; northeast region and northern west and peninsular Indian sub-divisions show oppositic correlation tendency. Significant change in mean rainfall of six sub-divisions is noticed. Correlogram and spectrum analysis show the presence of 14-year and QBO cycles in a few sub-divisional rainfall series.

The interannual variability of all-India summer monsoon (June to September) rainfall and its teleconnections with the southern oscillation index (SOI) and sea surface temperature (SST) anomaly of the eastern equatorial Pacific ocean have been examined for the period 1871–1978 for different seasons (i.e., winter, spring, summer and autumn). The relationship (correlation coefficient) between all-India summer monsoon rainfall andSOIfor different seasons is positive and highly significant. Further examination of 10-, 20- and 30-year sliding window lengths’ correlations, brings out the highly consistent and significant character of the relationships. The relationship between all-India monsoon rainfall andSSTfor different seasons is negative and is significant at 1 % level or above. Drought years are characterised by negative anomalies ofSOIand positive anomalies ofSSTand vice versa with flood years. The relationship betweenSOIandSSTis negative and significant at 0.1 % level.

The paper reports the findings of environmental surveys conducted in three paper mills situated in south India. Harmful exposures of the workers to the choking wood dust, irritating chlorine gas, offensive mercaptan odours, toxic talc dust, caustic lime dust, etc. have been pointed out.

The article offers news briefs on training programmes in India. A training programme on International Organization for Standardization (ISO) 9001:2008 Quality Management Systems and Internal Quality Audits was inaugurated by Doctor B.B. Bindroo, Director 1/c of Central Silk Research & Training Institute Berhampore. Two training programmes in cocoon handicrafts were held for 30 women sericulturists. A farmers' training programme was organized by Research Extension Centre, Deogarh.

This section offers news briefs related to sericulture in India. A buyer-seller meet was organized by Muga Raw Material Bank to create awareness about the different aspects of muga industry at Sivasagar in Assam on March 16, 2010. The Regional Sericultural Research Station inaugurated the Resham Krishi Mela at Kalimpong on March 23, 2010. The National Silkworm Seed Organization conducted a training program for officials of the West Bengal Silkworm Seed Production Centres at Berhampore from April 19 to 21, 2010.

The article reports on the ISO 9001:2008 Awareness Programme organized by the Indian National Silkworm Seed Organization.