Studies on Antifungal Properties of Essential Oil of Trachyspermum ammi (L.) Sprague

The essential oil from the fruits of Trachyspermum ammi exhibited toxicity at 800 ppm against Aspergillus flavus and A. niger, the nature of toxicity being cidal. The toxicity of the oil was not affected by autoclaving, temperature treatment and storage upto 365 days. The oil killed the test fungi within 50 seconds; withstood heavy inoculum density and was inhibitory to as many as 21 fungi at its minimum inhibitory concentration. However the seeds of Arachis hypogea whentreated with oil at 5000 ppm and stored for 12 months did not show the appearance of any fungi indicating thereby the grain protectant activity of the oil. The oil was characterized by various physico chemical properties and on chemical investigation Thymol and p-cymene were isolated as antifungal principles of the oil exhibiting toxicity against the test fungi at 1000 ppm.     

Seasonal adiposity and androstenedione production as a possible mechanism for asynchronous reproductive activity between males and females of vespertilionid bat, Scotophilus heathi

Relationship between changes in the body weight and circulating androstenedione concentration was examined in order to find out their involvement in asynchronous gametic cycle of male and female S. heathi. Body weight of both male and female bats increased from September due to accumulation of white adipose tissue and reached to a peak in November. The body weight declined gradually due to consumption of adipose tissue during December and January reaching basal level in February. A significant correlation between body weight and serum androstenedione concentration was observed. Correlated with maximum body weight, peak androstenedione level was found during November in both male and female bats. Peak androstenedione level during November may be responsible for stimulating spermatogenesis in the male, but may suppress follicular growth and ovulation in the female, thus resulting in asynchronous gametic cycle of male and female S. heathi.     

Foliar Spraying of Potassium Nitrate,Salicylic Acid,and Thio-urea Effects on Growth,Physiological Processes,and Yield of Sodicity-Stressed Paddy (Oryza sativa L.) with Alkali Water Irrigation

Journal of Plant Growth Regulation - Exogenous applications of plant growth regulators (PGRs) were evaluated for their effects on growth, physiological attributes, and yield of sodicity stressed...     

The replication origin of <Emphasis Type="Italic">Azotobacter vinelandii</Emphasis>

The putative replication origin of Azotobacter vinelandii was cloned as an autonomously replicating fragment after ligation to an antibiotic resistance cartridge. The resulting plasmids could be isolated and labelled by Southern hybridisation with the antibiotic resistance cartridge as probe and also visualised by electron microscopy. These plasmids integrated into the chromosome after a few generations, even in the recA mutant of A. vinelandii. The integrated copy of the plasmid was re-isolated from the chromosome and the DNA and its subfragments were cloned in the plasmid vector pBR322. A 200-bp DNA fragment was sufficient to allow the replication of pBR322 in an Escherichia coli polA strain. Electron microscopic analysis of this plasmid showed that replication initiated mostly within the A. vinelandii DNA fragment. The nucleotide sequence of the putative replication origin and its flanking regions was determined. In the sequence of the 200-bp fragment many of the distinctive features found in other replication origins are lacking. A greater variation from the consensus DnaA binding sequence was observed in A. vinelandii. Direct sequencing of the relevant genomic fragment was also carried after amplifying it from A. vinelandii chromosomal DNA by PCR. This confirmed that no rearrangements had taken place while the cloned fragment was resident in E. coli. It was shown by hybridisation that the 200-bp chromosomal origin fragment of A. vinelandii was present in three other field strains of Azotobacter spp.