Influence of climate change on Helicoverpa armigera (Hubner) in pigeonpea

Annual monitoring of the population dynamics of Helicoverpa armigera in unprotected pigeonpea crop during kharif seasons of 2011 to 2014 for 4 years at the farmers field North Gujarat, India. Temperature, rainfall and host-plant species were analyzed with respect to population fluctuation of the insect pest. The observations revealed that, the average number of larval population per plant in the season (from 27th to 3rd standard weeks) was 0.97, 0.32, 0.30 and 0.38 larvae/plant during 2011, 2012, 2013 and 2014 respectively. Population of Helicoverpa armigera had significant and negative correlation with maximum temperature (r= -0.524), rainfall (r= 0.079) and relative humidity (r= -0.827, r= -0.595 morning and evening, respectively)

Effects of extracellular nucleotides on renal tubular solute transport

A range of P2 receptor subtypes has been identified along the renal tubule, in both apical and basolateral membranes. Furthermore, it has been shown that nucleotides are released from renal tubular cells, and that ectonucleotidases are present in several nephron segments. These findings suggest an autocrine/paracrine role for nucleotides in regulating tubular function. The present review catalogues the known actions of extracellular nucleotides on tubular solute transport. In the proximal tubule, there is firm evidence that stimulation of apical P2Y1 receptors inhibits bicarbonate reabsorption, whilst basolaterally applied ATP has the opposite effect. Clearance studies suggest that systemic diadenosine polyphosphates profoundly reduce proximal tubular fluid transport, through as yet unidentified P2 receptors. To date, only circumstantial evidence is available for an action of nucleotides on transport in the loop of Henle; and no studies have been made on native distal tubules, though observations in cell lines suggest an inhibitory effect on sodium, calcium and magnesium transport. The nephron segment most studied is the collecting duct. Apically applied nucleotides inhibit the activity of small-conductance K+ channels in mouse collecting duct, apparently through stimulation of P2Y2 receptors. There is also evidence, from cell lines and native tissue, that apically (and in some cases basolaterally) applied nucleotides inhibit sodium reabsorption. In mice pharmacological profiling implicates P2Y2 receptors; but in rats, the receptor subtype(s) responsible is/are unclear. Recent patch-clamp studies in rat collecting ducts implicate apical P2Y and P2X subtypes, with evidence for both inhibitory and stimulatory effects. Despite considerable progress, clarification of the physiological role of the tubular P2 receptor system remains some way off