Genetic diversity among cultivars, landraces and wild relatives of rice as revealed by microsatellite markers

Genetic diversity among 35 rice accessions, which included 19 landraces, 9 cultivars and 7 wild relatives, was investigated by using microsatellite (SSR) markers distributed across the rice genome. The mean number of alleles per locus was 4.86, showing 95.2% polymorphism and an average polymorphism information content of 0.707. Cluster analysis based on microsatellite allelic diversity clearly demarcated the landraces, cultivars and wild relatives into different groups. The allelic richness computed for the clusters indicated that genetic diversity was the highest among wild relatives (0.436), followed by landraces (0.356), and the lowest for cultivars. Allelic variability among the SSR markers was high enough to categorize cultivars, landraces and wild relatives of the rice germplasm, and to catalogue the genetic variability observed for future use. The results also suggested the necessity to introgress genes from landraces and wild relatives into cultivars, for cultivar improvement.     

Fluidised bed drying of agro products

Agro products like raagi, millets and caraway were dried in a fluidised bed dryer and their heat and mass transfer coefficients evaluated during the constant rate period. The Nusselt number and Sherwood number were related to Peclet number and bed height to particle size ratio. Generalised relations of the form, Nu = a(Pe_h)^b(H/d_p)^c Sh = d(Pe_m)^e(H/d_p)^f has been proposed.     

Effect of an LHRH agonist on pituitary and testicular function in rhesus monkeys

Male rhesus monkeys were given 100 micrograms [(imBzl)-D-His6,Pro9-NEt]-LHRH (LHRH-A), a potent LHRH agonist, s.c. daily for 40 weeks. The first dose of LHRH-A caused acute increases (2-4 h after injection) in serum LH (50-fold), FSH (2 X 5-fold) and testosterone (15-fold) concentrations. Chronic treatment led to a 95% decrease in LH and FSH responses. In spite of a marked decrease in LH response the effect on testosterone response was less evident. Administration of 50 i.u. hCG to control and LHRH-A-treated animals showed that the testicular steroidogenic response was unimpaired by the chronic treatment. Evaluation of the electroejaculated semen at regular intervals showed that there was no consistent reduction in the sperm count of LHRH-A-treated monkeys. Testicular biopsies showed that normal spermatogenesis was occurring in all treated animals, but testicular volume was significantly decreased. These results suggest that, in rhesus monkeys, the pituitary is more susceptible to desensitization by chronic LHRH agonist treatment than are the testes, and that LHRH agonists do not have direct antitesticular effect in rhesus monkeys.     

Lactic dehydrogenase isozyme distributions in lymphocytes from normal and leukemic mice

LDH isozyme distributions were studied in the thymocytes of normal and spontaneously leukemic mice. In the normal animals, H:M ratios were found to be higher for more mature cells of adult animals than for less mature thymocytes of the neonates. However, thymocytes from leukemic animals bearing mature phenotype displayed very low values of H:M ratios. From these results, the relationship between the changes in LDH-isozyme distributions in AKR thymocytes and their progressive maturation appears to be equivocal. Alterations in isozyme distribution patterns, reflecting a decrease in H:M ratios, on the other hand, appears to be a characteristic feature of terminal stages of this murine leukemia.