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Twenty-seven advanced lines including three exiting varieties (BARI Gom 21, BARI Gom 32 and BARI Gom 33) were evaluated in alpha lattice design with two replications at Bangladesh Wheat and Maize Research Institute, Dinajpur and regional stations at Joydebpur, Jashore and Rajshahi under irrigated timely sown (ITS) and irrigated late sawn (ILS) conditions. The objective of the study was to find out the heat-tolerant wheat lines for future breeding programme to develop heat-tolerant wheat varieties. The genotypes were evaluated for phenological variation such as heading and maturity, yield and yield components, disease reaction, sterility, visual grain quality, etc. The results showed that the highest grain yield (5951 kg ha-1) was recorded with genotype BAW 1415 at Dinajpur under ITS condition and the lowest grain yield (1923 kg ha-1) was observed in BAW 1416 at Rajshahi under ILS condition. Considering the overall performances, genotypes BAW 1402, BAW 1403, BAW 1406, BAW 1407, BAW 1408, BAW 1411, BAW 1422 and BAW 1425 performed better. Considering disease infestation, genotypes BAW 1374, BAW 1393, BAW 1394, BAW 1397, BAW 1399 and BAW 1401 showed a good level of resistance to both leaf rust (LR) and wheat blast (WB). These genotypes could be selected for future breeding programmes to develop heat-tolerant and diseases resistance varieties. Bangladesh J. Agri. 2022, 47(2): 1-16

Peat wildfires can burn over large areas of peatland, releasing ancient carbon and toxic gases into the atmosphere over prolonged periods. These emissions cause haze episodes of pollution and accelerate climate change. Peat wildfires are characterised by smouldering – the flameless, most persistent type of combustion. Mitigation strategies are needed in arctic, boreal, and tropical areas but are hindered by incomplete scientific understanding of smouldering. Here, we present GAMBUT, the largest and longest to-date field experiment of peat wildfires, conducted in a degraded peatland of Sumatra. Temperature, emission and spread of peat fire were continuously measured over 4–10 days and nights, and three major rainfalls. Measurements of temperature in the soil provide field experimental evidence of lethal fire severity to the biological system of the peat up to 30 cm depth. We report that the temperature of the deep smouldering is ~13% hotter than shallow layer during daytime. During night-time, both deep and shallow smouldering had the same level of temperature. The experiment was terminated by suppression with water. Comparison of rainfall with suppression confirms the existence of a critical water column height below which extinction is not possible. GAMBUT provides a unique understanding of peat wildfires at field conditions that can contribute to mitigation strategies.

Evaluation in standardization really needs to be carried out, including whether the livestock is in accordance with the SNI vital statistics standard (Indonesian national standard). The purpose of the study was to estimate heritability and breeding values of body weight and vital statistics in Etawah Grade (PE) goats in BPTU and HPT Pelaihari Kalimantan Selatan. The material used were the performance records of 220 PE goats, offsprings of 35 males and 71 females. The variables measured were body length and chest girth at birth, weaning, and 1 year of age. Variance componenet were analyzed using variance analysisrade. Heritability was estimated using the paternal half-sib correlation method by applying SPSS software. Breeding value was estimated using the progeny test model. The highest breeding value on body length at birth, at weaning age and at 1 year of age were sire 3315 KK, sire 4093 OK, and sire 4007 OK, respectively. The highest breeding Value on chest girth at birth, weaning age and 1 year of age were sire 3983 HH, 3315 HH, and 3971 HH. The conclusion of this study were the heritability for body weight were categorized high and for statistic vital were varied from medium to high value.

Peatland wildfires present challenge to the mitigation of climate change due to the large amount of ancient carbon emission. Once ignited, the organic soils in peatland can burn for a long periods (weeks to months) and are difficult to extinguish. Peat fire is governed by smouldering combustion which is the slow, low temperature, flameless burning of charring porous fuel, and the most persistent type of combustion phenomena. The detection and monitoring of peatland wildfires are often conducted by remote sensing like satellite. However, there is currently a missing gap between spread of peat fires in the small laboratory scale and the large field scale. This work covers this gap by conducting field-scale controlled experiment of peatland wildfires. The experimental campaign, GAMBUT, was conducted in the peatland of Sumatra, Indonesia, covering an area of 374 m2. Smouldering spread rate was measured by infrared cameras and subsurface thermocouples. The smouldering sustained up to 10 days and nights, and survived against three rainfalls. Observation from infrared images show that horizontal smouldering spread rate fluctuates during propagation. However, no significant difference was found between average horizontal spread rates from the measurements of infrared camera and thermocouples, i.e. 0.3±0.13 cm/h to 0.8±0.2 cm/h. The spread rates here agree with the trend in the literature of laboratory experiments, fit within in the ranges of high moisture (MC) and inorganic (IC) contents of the soil (MC between 23 to 141% and IC between 49 to 72%). Even though slower, the fires thrived up to 10 days and against three rainfalls, demonstrating the persistency of smouldering peat fires and calling for a consideration of degraded peatland with high inorganic content to be consistently included in the mapping and monitoring of peatland area. GAMBUT presents a unique understanding of peatland wildfires at field conditions and aims to contribute to the better monitoring and mitigation acts.

The experiment was carried out with 50 wheat lines to study their mean, range, cv (%), correlation co- efficient, and path co- efficient considering 14 different morphological characters at the experimental field of Regional Wheat Research Centre (RWRC), Bangladesh Agricultural Research Institute (BARI), Gazipur during December 2010 to April 2011. Significant variation was observed among the genotypes for all characters studied. In general, genotypic correlations were higher than the phenotypic correlations. It indicates that there was an inherent association among them which was adversely influenced by the environment. The correlation coefficients showed that, seed yield was negatively and significantly correlated with days to heading (DTH), plant height (PHT), days to anthesis (DTA), days to physiological maturity (DPM), and canopy temperature at anthesis stage (CTanth.) but only negatively correlated with canopy temperature at vegetative stage (CTveg.), canopy temperature at grain filling stage (CTgf.), spikelets per spike both genotypically and phenotypically and grain per spike showed genotypically negative correlation. Path analysis showed that plant height (PHT), days to physiological maturity (DPM), canopy temperature at grain filling stage (CTgf.), and thousand grain weight (TGW) influenced seed yield directly in positive direction but days to heading (DTH), days to anthesis (DTA), grain filling duration (GFD), grain filling rate (GFR), Chlorophyll content at anthesis stage (CHLA), canopy temperature at vegetative stage (CTveg.), canopy temperature at anthesis stage (CTanth.), spikelets per spike, and grains per spike had negative direct effect on seed yield. Considering analytical findings of correlation co-efficient, path co-efficient analysis and field performance, the genotypes G 3, G 10, G 11, G 12, G13, G 21, G 29, G 35, G 38, G 40, G 46 and G 48 were found suitable for future breeding programme.Bangladesh J. Agril. Res. 42(3): 571-588, September 2017

In this paper, we present the design, fabrication, and characterization of a long-arm comb-drive actuator with an externally mounted large mirror for optical applications. The provision for an externally mounted mirror can be useful for many optical applications, which require large and high-quality reflecting surfaces. The angular stretch of the comb fingers at the far end is kept smaller than those near the anchor point. This structural feature allows the design of actuator arm lengths of over 5 mm. The truss of the actuator is designed carefully to support the large movable arm. An analytical model for the electrostatic forces in the actuator was developed, and detailed analyses for side instability and resonance frequency were performed. The complete fabrication process involving bulk micromachining of silicon-on-insulator (SOI) wafer using a two-mask process is described. A procedure for efficient mounting of the mirror utilizing die bonder, vacuum tip, and silver epoxy is demonstrated. Static characterization measurements show that the actuator can achieve a rotational angle of 3° with an applied voltage of 130 V. A resonance frequency of $\sim 246$ Hz for a mirror size of $2~\textrm {mm} \times 100~\mu \textrm {m} \times 1$ mm was determined by optical characterization; this closely matches with the simulation results and the analytical model. [2014-0318]

Genetic divergences of 50 wheat lines were studied through Mohalanobis’s D2 and principal component analysis for fourteen characters. Genotypes were grouped into four different clusters. Cluster II comprised maximum number of genotypes (twenty one) followed by cluster IV. The inter-cluster distance was maximum between clusters I and III (12.29) indicating wide genetic diversity between these two clusters followed by the distance between cluster I and cluster II (8.28), and cluster III and cluster IV (7.97). The minimum inter-cluster distance was observed between cluster II and cluster IV (4.193) followed by cluster I and cluster IV (4.339) and cluster II and cluster III(4.390) indicating that the genotypes of these clusters were genetically close. The intra cluster distance of all the four clusters was more or less low which indicated that the genotypes within the same cluster were closely related. The highest inter genotypic distance (0.9166) was observed between the genotypes G 40 and G 41and lowest (0.0993) between the genotypes G 22 and G 43. Among the characters, heading days, maturity days, plant height (cm), canopy temperature at vegetative stage, canopy temperature at grain filling stage, grain filling rate (g d-1m-2), 1000- grain weight (g), and grains spike-1 contributed most for divergence in the studied genotypes. Cluster I had the highest mean for grain yield (4711.2 kg/ha), grain filling rate (17.5 g d-1m-2), chlorophyll content at anthesis, and plant height (93 cm). Crosses between I & III, I & II, and III & IV have greater chances to generate more heterotic F1s. Considering magnitude of genetic distance, contribution of different traits toward the total divergence, magnitude of cluster means for different traits and performance the genotypes G10, G 11, G12, G35, G40, G48 of cluster I, G7 of cluster II, G41, G5,and G3 of cluster III and G46, G21 of cluster IV may be considered as good parents for future hybridization program to produce high yielding genotypes. DOI: http://dx.doi.org/10.3329/bjar.v39i2.20414 Bangladesh J. Agril. Res. 39(2): 189-196, June 2014

The present investigation was undertaken with the objective to identify the extent of genetic diversity for traits related to heat tolerance among 25 currently available spring wheat genotypes under late sowing condition during the cropping season 2009-2010. All genotypes were distributed into five clusters showing considerable genetic divergence for most of the heat tolerant traits under study. The role of grain filling rate and biomass production in both the vectors had the highest contribution to genetic divergence. The positive values of both the vectors for flag leaf senescence, ground coverage, spikes number, 1000-grain weight, grain yield (g m-2) and harvest index indicating high contribution of these traits towards the divergence among 25 genotypes of wheat. Three pair of clusters, viz. I & II, I & III and I & V can be considered for obtaining more heterotic progeny as the genetic distance between these clusters were larger. Considering yield performances, cluster distance and cluster mean the genotype G-22 from cluster I and genotype G-14 from cluster IV may be considered better parents for further breeding of heat tolerance as they showed maximum divergence and high degree of tolerance to heat under late sowing condition. Moreover, the genotype G-22 could be exploited for direct release as a heat tolerant variety after testing under wider range of environments.DOI: http://dx.doi.org/10.3329/bjpbg.v25i2.18663

An approach for controlling sidewall smoothness through deep reactive ion etch (DRIE) was developed for silicon micro-optical applications. The process relies on carefully controlled over-passivation of the etched sidewall during the etch/passivation cycles of the advanced Si etch (ASE) process. Several parameters of the ASE process such as etch/passivation cycle time, coil power, platen power, and etching gas flow were systematically varied to achieve an optimized process recipe. The rms roughness of the sidewall after gold deposition was found to be around 3.9 nm. Our structure represents the lowest reported sidewall roughness achieved using only a DRIE process.

Rotary comb-drive electrostatic actuators with virtual pivotal point of rotation were designed and fabricated for their application in external cavity tunable lasers in Littman configuration. Silicon on insulator (SOI) wafers with device layer thickness of 50 μm and buried oxide layer of 2 μm were used. The structures were fabricated through bulk micromachining of the device layer followed by release of movable arms through wet etching. Six pairs of comb arms were used to symmetrically distribute electrostatic forces on an interconnected movable arm structure. The movable structure consisting of stiff truss connectors in arc shapes on inner and outer periphery was anchored through three beams. Actuation of the movable arms on a circular profile with a virtual pivotal point was achieved for the designed range of operation. A maximum rotation of ± 1.5 degrees at 190 V was achieved. The dimensions of the movable arm are on the order of 1.2-1.5 mm. The actuators have a physical clearance of up to 2.8 mm from the device structure to the virtual pivot point. The sidewalls of the movable arms are accessible for optical applications. The geometrical configuration of the fabricated structures supports the stringent requirements of optical path alignments in external cavity lasers. The fabricated structures can be reliably operated in the kilohertz range

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Rotary comb-drive electrostatic actuators with smooth vertical sidewalls were designed and fabricated for photonic applications. Silicon on insulator (SOI) wafers with device layer thicknesses of up to 100 μm and oxide layers of 1-2 μm were used. Structures were fabricated through bulk micromachining of the handle layer followed by removal of the buried oxide. Deep reactive ion etching (DRIE) of the device layer defined the comb structure with simultaneous release of the moving arm. Thick photoresist and oxide masking layers were used for the high aspect ratio deep etches. Notching effects or depth variations of device layers were not observed. Etch/ passivation cycles in DRIE were optimized to obtain smooth sidewalls. Traces of etch scallops were confined only to the first few microns of the top and bottom edges of the reflecting sidewall. A movable arm length of 2 mm with a maximum rotation of 2.8 degrees was achieved. The edge deflection was over 100 μm at 100 volts. The fabricated structure provides a long reflecting sidewall that is accessible for hybrid integration in three dimensional space. The fabricated structures can be reliably operated in the kilohertz range.

Rotary comb-drive electrostatic actuators with smooth vertical sidewalls were designed and fabricated for photonic applications. Silicon on insulator wafers with device layer thicknesses of up to 100 μm and oxide layers of 1 to 2 μm were used. Structures were fabricated through bulk micromachining of the handle layer, followed by removal of the buried oxide. Deep reactive ion etching (DRIE) of the device layer defined the comb structure with simultaneous release of the movable arm. Thick photoresist and oxide masking layers were used for the high aspect ratio deep etches. Notching effects or depth variations of device layers were not observed. Etch/passivation cycles in DRIE were optimized to obtain smooth sidewalls of less than 5 nm roughness. Traces of etch scallops were confined only to the first few microns of the top and bottom edges of the reflecting sidewall. A movable arm length of 2 mm with a maximum rotation of 2.8 deg was achieved. The edge deflection was over 100 μm at 100 V. The fabricated structure provides a long reflecting sidewall, that is accessible for hybrid integration, in three dimensional space. The fabricated structures can be reliably operated in the kilohertz range.

A field experiment was conducted at the central research farm of Bangladesh Agricultural Research Institute, Gazipur for two consecutive years to verify the yield response of wheat variety Prodip to different doses and split applications of N fertilizer to determine appropriate N dose and application method for increasing NUE and grain yield of wheat. The treatments comprised of 12 combinations of three doses of nitrogen (80, 100, and 120 kg/ha) from urea, which were assigned in the main plots and four methods of N splitting viz., application of all N as basal; 2/3rd basal plus 1/3rd as top dress at crown root initiation (CR1) stage; 1/2 basal plus 1/2 as top dress at CR1 stage; and 1/3rd basal with 1/3rd as top dress at CR1 plus 1/3rd as top dress at 1st node stage which were tested in the sub plots. Higher yield was achieved from N rate of 120 kgiha applied as three equal splits of one-third as basal during final land preparation, one-third as top dressing during CR1 and the rest one-third top dressing at first node stage. The yield advantage of wheat due to N treatments was attributed to higher thousand grain weight and spikes/m2. Nitrogen content in wheat grain and straw was not affected significantly by different N treatment and their combinations, whereas plant N uptake was significantly influenced by N rate and N splitting and also due to the interaction of N rate and N splitting. Total N uptake was maximum under N rate of 120 kg/ha applied as three equal splits as 1/3rd basal with 1/3rd as top dress at CR1 plus 1/3rd as top dress at 1st node stage. Split applications of sub-optimal dose of N (80 kg/ha) resulted in negative gain in apparent NUE, but split applications, especially three split applications (1/3rd basal, 1/3rd at CR1, and 1/3rd at 1st node stage) of higher dose of N (100 and 120 kg/ha) resulted in positive gain in apparent NUE. Keywords: Wheat grain yield; nitrogen management; N uptake and NUE DOI: http://dx.doi.org/10.3329/bjar.v36i2.9249 BJAR 2011; 36(2): 231-240