RESPONSE OF NITROGEN FERTILIZATION ON BT AND NON-BT COTTON (Gossypium hirsutum) HYBRIDS
A field experiment was conducted during 2006 and 2007 (June- December) at New Delhi to assess the performance of three cotton hybrids of which two Bt (MRC 6304 & RCH 317) and one non-Bt cotton hybrid LHH 144 (North zone check) in response to nitrogen fertilization (0, 60, 120 and 180 kg ha -1 ). Based on pooled analysis, both Bt hybrids produced similar seed cotton yield (SCY). Bt hybrid have produced 7.1 bolls/plant (on an average) and bolls 0.48 g heavier than non Bt hybrid LHH 144 that lead to 1.07 t ha -1 higher SCY of Bt hybrids than non-Bt hybrid (1.93 t ha -1 ). Though the N uptake by cotton hybrids was statistically similar N harvest index (NHI) was higher in Bt hybrid (57.85) as compared to non-Bt hybrid (40.5). The agronomic N use efficiency (ANUE) was highest in MRC 6304 Bt (6.44) and least in LHH 144 non-Bt cotton (3.91). Cotton growth, yield attributes, SCY, and N uptake increased with each successive increase to the highest level of 180 kg ha -1 however, the N response of cotton was quadratic in nature with optimum dose of 173.0 kg ha -1 . The NHI decreased with increase in N dose i.e. from the highest of 56.3 in control to the lowest of 48.8 with 180 kg ha -1 N fertilization. ANUE and physiological NUE that was highest with 60 (5.73) and 120 kg N fertilization (17.05), respectively and decreased with further increase in N dose. The cotton hybrid x N interaction effect revealed that Bt cottons have quadratic N response while non-Bt cotton has linear N response. From the economic point of view, Bt hybrids with 120 kg Nha -1 could be optimum dose for cotton cultivation. DOI:  http://dx.doi.org/10.3329/sja.v11i1.18389 SAARC J. Agri., 11(1): 121-132 (2013)
Direct and residual effects of nitrogen management in Bt cotton (Gossypium hirsutum)-wheat (Triticum aestivum) cropping system.
A 2-year field investigation was carried out in New Delhi from 2006 to 2008 on a sandy loam soil having 217 kg/ha of available N. In cotton (Gossypium hirsutum L.) 8 treatments comprising combination of 4 N management practices {Control, 100% recommended dose of N (150 kg/ha) through urea (RDN), 75% RDN through urea + 25% RDN through FYM N and 50% RDN each through urea and FYM) and 2 cropping systems - sole cotton and cotton + groundnut (Arachis hypogaea L.) intercropping in 1:3 additive series. N management in cotton-wheat cropping system were tested in RBD with 3 replications. For comparison, sole groundnut with recommended N and phosphorus fertilizers was also grown. In rabi, cotton plots were sub-divided in to 4 to accommodate levels of N (0, 50, 100 and 150 kg/ha) to wheat. Groundnut as an intercrop enhanced the productivity of cotton by 0.25 tonne/ha and succeeding wheat by 0.16 tonne/ha. These increases in productivity of cotton and wheat coupled with additional intercrop groundnut yield (0.47 tonne/ha) together enhanced the productivity of cotton + groundnut - wheat systems in seed cotton equivalent yield by 0.58 tonne/ha and net returns by Rs 14,421/ha over cotton-wheat system. Among N management practices, substitution of 25% RDN through FYM in cotton gave the highest system productivity (4.82 tonne seed cotton equivalent yield/ha) and B: C ratio (2.09) than all N through urea and 50% N through each source. However, net returns and soil N balance were in favour of 50% RDN substitution through FYM besides (Rs 72,748/ha). Wheat crop responded to100 kg N/ha fertilization. It was therefore inferred that integration of groundnut as intercrop along with FYM besides 50% N of cotton along with 100 kg fertilizer N/ha to wheat was the most profitable and sustainable N management system.
Instrumentation and Automated Photometric Titration Procedure for Total Acidity Determination in Red Wine Employing a Multicommuted Flow System
An automated procedure for photometric titration of red wine and associated instrumentation is described. The procedure was based on the flow-batch approach implemented employing multicommutation. The photometric detection was carried out using a homemade LED-based photometer. The mixing device, LED, and photodetector were attached to the titration chamber in order to form a compact and small-sized unit. The flow system comprised an automatic injector and three-way solenoid valves, which were controlled by a microcomputer through an electronic interface card. The software, written in Quick BASIC 4.5, was designed with abilities to accomplish all steps of the titration procedure including data acquisition and real-time processing to decide about the course of titration in the following step and so forth, until the titration endpoint was reached. The usefulness of the proposed titration system was demonstrated by analyzing red wine samples. When results were compared with those obtained using the AOAC reference method, no significant difference was observed at the 95% confidence level. A relative standard deviation of ca  2% (n=9 ) was obtained when processing a typical red wine sample containing 7.3 gl -1 total acidity expressed as tartaric acid.