Stigmatic receptivity determines the seed set in Indian mustard, rice and wheat crops.

Stigmatic receptivity restricts the successful pollination in cereal crops. The present study deals with the biochemical test for enzymes producing in stigma of field crops such as Indian mustard, rice and wheat. The alcohol dehydrogenase and hydrogen peroxide assays revealed stigmatic receptivity as a violet color and oxygen bubbles released by the chemical reaction. Therefore, the 2 quick tests are in conformity to each other and supported the seed set data, which was utmost at blooming stage of flower ranged between 2-4 d All the 3 crops showed variation in stigmatic receptivity with respect to different time periods of blooming stages and hence, it may affects simultaneous pollen germination and tube growth, fertilization and seed set. The present finding suggests that the growth of pollen tube and stigma receptivity could be influenced by specific enzymes on stigma surface after 2-4 d of blooming stage, which contributes to proper seed set.

Gibberellic acid in plant: still a mystery unresolved.

Gibberellic acid (GA), a plant hormone stimulating plant growth and development, is a tetracyclic di-terpenoid compound. GAs stimulate seed germination, trigger transitions from meristem to shoot growth, juvenile to adult leaf stage, vegetative to flowering, determines sex expression and grain development along with an interaction of different environmental factors viz., light, temperature and water. The major site of bioactive GA is stamens that influence male flower production and pedicel growth. However, this opens up the question of how female flowers regulate growth and development, since regulatory mechanisms/organs other than those in male flowers are mandatory. Although GAs are thought to act occasionally like paracrine signals do, it is still a mystery to understand the GA biosynthesis and its movement. It has not yet confirmed the appropriate site of bioactive GA in plants or which tissues targeted by bioactive GAs to initiate their action. Presently, it is a great challenge for scientific community to understand the appropriate mechanism of GA movement in plant's growth, floral development, sex expression, grain development and seed germination. The appropriate elucidation of GA transport mechanism is essential for the survival of plant species and successful crop production.

Pentachlorophenol degradation by Pseudomonas stutzeri CL7 in the secondary sludge of pulp and paper mill.

A pentachlorophenol (PCP) mineralizing bacterium was isolated from the secondary sludge of pulp and paper mill and identified as Pseudomonas stutzeri strain CL7. This isolate used PCP as its sole source of carbon and energy and was capable of degrading this compound as indicated by stoichiometric release of chloride and biomass formation. P. stutzeri (CL7) was able to mineralize a high concentration of PCP (600 mg/L) than any previously reported Pseudomonad with PCP as sole carbon source. As the concentration of PCP increased from 50 to 600 mg/L, the reduction in the cell growth was observed and the PCP degradation was more than 90% in all studied concentrations. This isolate was able to remove 66.8% of PCP from the secondary sludge of pulp and paper mill when supplemented with 100 mg/L of PCP and grown for two weeks. This study showed that the removal efficiency of PCP by CL7 was found to be very effective and can be used in PCP remediation of pulp paper mill waste in the environment.

Hepatitis B surface antigen (HBsAg) in leprosy patients of Calcutta: its prevalence and subtypes.

Hight incidence of hepatitis B surface antigen (HBsAg) in lepromatous leprosy patients have been reported by many workers. This paper reports on a study undertaken over a period of more than two years to determine the prevalence of HBsAg and its major antigenic subtypes amongst the various clinical types of leprosy and apparently healthy individuals of Calcutta population. The overall incidence of HBsAg in lepromatous leprosy is found to be 3.8% (9 out of 234) in our study. The incidence of HBsAg in tuberculoid leprosy and non leprosy control cases were almost identical, 2.5% (11 out of 431) and 2.7% (14 out of 519) respectively. The incidence of HBsAg in lepromatous leprosy in the present study was apparently higher than tuberculoid or non leprosy cases, although statistically not significant. Hence the association between HBsAg and lepromatous leprosy could not be established in our study. None of the major antigenic subtypes of HBsAg could be related to any particular type of leprosy. The subtypes 'ad', 'ay' and 'ar' were present at varying proportions in all the groups tested. The antigenic subtype 'ay' was found to be prevalent in Calcutta population in higher proportions.