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Coccinellids are key predators that are conserved and augmented in agricultural ecosystems, to achieve biological control of pests. Actual quantification of field predation has not been attempted for many of the beneficial coccinellids. Numerous reports show coccinellids as opportunistic, feeding on a variety of food material in addition to their preferred prey. Micraspis discolor is the most abundant species of coccinellid in rice ecosystems and touted as a biocontrol option for brown planthopper ( BPH), Nilaparvata lugens (Stal), a key pest of rice. However, it has been reported as both entomophagous and phytophagous. Native polyacrylamide gel electrophoresis ( PAGE) was used to separate esterases from whole-body homogenates of Micraspis and its prey viz., green leafhopper ( GLH) Nephotettix virescens ( Distant), BPH N. lugens, whitebacked planthopper ( WBPH) Sogatella furcifera (Horvath), aphid Rhopalosiphum padi L., thrips, Haplothrips sp., and pollen. Field-collected beetles showed a range of bands, some corresponding with pollen and GLH, while others were different from prey offered, indicating a wider range of prey spectrum than envisaged. Feeding preference studies confirmed a preference for pollen and GLH in no-choice ( H = 20.724; P = 0.001) and multiple-choice tests ( H = 20.52; P < 0.001) and a significant preference for pollen over all insects offered in the paired-choice test ( t = 5.099; P = 0.007). The abundance of adult M. discolor in rice at flowering phase does not correspond to prey abundance in the field but rather reflects an inclination to pollen feeding more than entomophagy. [ABSTRACT FROM AUTHOR]

Influence of leaffolder feeding on chlorophyll, PS II activity and plant-water relations, effect of larval density on leaf damage and time course studies on larval feeding behaviour on altered physiological changes in TN1 rice culture were studied. Quantification of yield losses in the field caused by leaffolder was also assessed. Leaffolder damage resulted in 57% reduction in chlorophyll content, 23% reduction in PS II activity and 23% reduction in relative water content in comparison with control. Rice leaffolder larva folds the leaf and scrapes the green tissue from within the fold resulting in scorching and drying of the leaves. Larval density had differentially influenced effective leaf area of rice crop. Larval densities of more than 3 larvae per hill at maximum tillering stage resulted up to 20% unfilled grains, 28-57% reduction in PS II activity and 23% reduction in relative water content in comparison with the control. At flowering stage, flag leaf area damage of above 25% resulted in more than 50% unfilled grains over control, indicating direct effect of yield reduction in rice. Thus, a cumulative effect of loss in chlorophyll, reduced photosynthate availability and altered water relations caused by the leaffolder injury to flag leaf lead to greater yield loss in rice. [ABSTRACT FROM AUTHOR]

The diversity of natural enemies harboured by flowering forbs on rice field bunds was recorded. Ageratum conozoides with a maximum Shannon diversity index of 1.8 followed by Acmella uliginosa, Eclipta alba and Tridax procumbens are amenable for ecological engineering, providing nectar, pollen and alternate prey to natural enemies. [ABSTRACT FROM AUTHOR]

In this paper, the quasi-static - (QSCV) measurement technique is applied to measure capacitance of 2-D (planar) and 3-D IC interconnect test structures. The advantages of the quasi-static approach such as the immunity from frequency dependence effects and the capability of measuring small capacitance values in the 100-fF range are particularly attractive for the characterization of the interconnect capacitance in planar and vertical architectures with small dimensions. Issues related to the QSCV measurements of leaky capacitors are analyzed and quantified. The capacitance of different 2-D and 3-D interconnect structures is measured, and the QSCV results are compared with capacitance values extracted from impedance measurements of the same structures in the frequency domain. [ABSTRACT FROM PUBLISHER]

Organic manuring influences the diversity of arthropods and their functional significance in rice fields. Arthropod diversity under eight organic manure regimes consisting of farmyard manure (FYM), vemiicompost (VC), poultry manure (PM), neem cake (NC), FYM + 50% recommended fertilizer dose (50%RFD), VC+50% RFD, RFD, and unfertilized control (UC) was assessed in a randomized block design experiment. The doses of organic amendments were adjusted to give the recommended level of 120 kg N ha-1. Arthropod sampling was carried out by sweep-nets, vacuum sampling, and straining. I ligher abundance of arthropods was observed in plots treated with VC and NC with the spider Tetragnatha sp. being the dominant species. Simpson's index indicated that the maximum diversity was observed in PM treated plots (0.022) while the least was in RFD plots (0,1 S3). [ABSTRACT FROM AUTHOR]

The study aims to compute the reference evapotranspiration (ETo) by six standard methods such as Penman Monteith, Modified Penman, Hargreaves, Radiation Balance, Blaney Criddle and Pan Evaporation by using the meteorological data of the All India Coordinated Research Project on Water Management at Rahuri, India (long. 74° 18′, lat. 19° 45′). These methods were compared with lysimeter crop evapotranspiration (ETc) by statistical tools. The results revealed that the total lysimeter ETc of red gram in 132 days' growing period (sowing to harvest) was 494 mm and the ETo in the above-mentioned models were 485.2, 486.9, 544.6, 547.6, 563.9 and 485.2 mm, respectively. Out of six models, ETo of Modified Penman and Pan Evaporation methods were very much close to lysimeter ETc, but the coefficient of variation was very high, i.e., 43.05% and 23.91%, respectively. But in the Hargreaves and Blaney Criddle methods, the coefficient of variation was low, i.e., 15.97% and 12.6%, respectively. Besides low coefficient of variation, these two methods require limited meteorological parameters such as minimum and maximum temperature, radiation. For generating these parameters even at regional level, minimum expenditure is involved. The crop coefficient (Kc) estimated by Hargreaves (Kc 0.90) and the Blaney Criddle (0.87) model for the entire growing season was very much close to the Food and Agricultural Organization (FAO) 56 model, and this can be used for estimating the irrigation requirement of red gram. [ABSTRACT FROM AUTHOR]