Molecular characterization and marker based chemotaxonomic studies of Podophyllum hexandrum Royle

Detailed chemical studies and RAPD analysis were done in different populations of Podophyllum hexandrum collected from high altitude regions of North Western Himalayas. Random amplified polymorphic DNA (RAPD) analysis revealed a high degree of genetic diversity among the 12 collected accessions, attributed to their geographical and climatic conditions. HPLC analysis also revealed variation in the concentration of two major marker compounds which lead to the identification of a chemotype. The study demonstrated that RAPD and chemical markers are very useful tools to compare the genetic relationship and pattern of variation among such prioritized and endangered medicinal plants.     

INTERACTIONS BETWEEN FIRST AND SECOND APPLICATIONS OF FERTILIZER NITROGEN AND IMPLICATIONS IN EFFICIENCY OF NITROGEN USE

DM yield and N uptake data are presented from primary growth and two successive regrowths of perennial ryegrass treated with combinations of three N treatments for the primary growth viz. 0, 50 and 100 kg N/ha (PN) and four N treatments applied for the second growths, viz. 0, 33, 66 and 100 kg N/ha (SN). Primary growth gave a response of 24·2 kg DM/kg applied N to PN50 with only a further l±0 kg DM/kg applied N from the second PN increment. A significant interaction between PN and SN treatments was shown in second growth. The residual DM response to PN was highest at SN0 and reduced as the level of SN was raised. Substantially greater residual responses to PN treatments were shown in the third growth. Third growth DM responses to SN treatments were high. High apparent recovery of fertilizer N reached 111% of primary N where SN66 followed PN50. High available soil N is partly responsible for both high apparent recovery of N and high DM response. The latter appears to be associated with inclusion of growths given no fertilizer N so that the full residual effects of fertilizer N and ‘priming’ of available soil N can be realised.     

Zur Anwendung von 2,4-Dichlorphenoxyessigsäure (2,4-D) bei Tomaten. Der Metabolismus des 2,4-D in Tomatenfrüchten

Due to 2,4-D-treatments of tomato inflorescences mainly glycosides of 4-Hydroxy-2,3-dichlorophenoxyacetic acid (4-OH-2,3-D) are formed in the fruits, and to a lesser extent of 4-Hydroxy-2,5-dichlorophenoxyacetic acid (4-OH-2,5-D), too. Acid hydrolysis of n-butanol extract also yielded 2,4-D, and in addition an unidentified metabolit. Only very small amounts of unchanged 2,4-D residues were detected (lower than 1 ppb).