Search

Abstract The high-quality genome of coconut (Cocos nucifera L.) is a crucial resource for enhancing agronomic traits and studying genome evolution within the Arecaceae family. We sequenced the Chowghat Green Dwarf cultivar, which is resistant to the root (wilt) disease, utilizing Illumina, PacBio, ONT, and Hi-C technologies to produce a chromosome-level genome of ~ 2.68 Gb with a scaffold N50 of 174 Mb; approximately 97% of the genome could be anchored to 16 pseudo-molecules (2.62 Gb). In total, 34,483 protein-coding genes were annotated; the BUSCO completeness score was 96.80%, while the k-mer completeness was ~ 87%. The assembled genome includes 2.19 Gb (81.64%) of repetitive sequences, with long terminal repeats (LTRs) constituting the most abundant class at 53.76%. Additionally, our analysis confirms two whole-genome duplication (WGD) events in the C. nucifera lineage. A genome-wide analysis of LTR insertion time revealed ancient divergence and proliferation of copia and gypsy elements. In addition, 1368 RGAs were discovered in the CGD genome. We also developed a web server ‘Kalpa Genome Resource’ ( http://210.89.54.198:3000/ ), to manage and store a comprehensive array of genomic data, including genome sequences, genetic markers, structural and functional annotations like metabolic pathways, and transcriptomic profiles. The web server has an embedded genome browser to analyze and visualize the genome, its genomics elements, and transcriptome data. The in-built BLAST server allows sequence homology searches against genome, annotated transcriptome & proteome sequences. The genomic dataset and the database will support comparative genome analysis and can expedite genome-driven breeding and enhancement efforts for tapping genetic gains in coconut.

Pollen collection and storage assume importance in hybridization programs in coconut. Development of an effective short-term storage method for coconut pollen ensures availability of pollen for coconut breeding throughout the year. In the present study, pollen collected from dwarf coconut cultivar Chowghat Orange Dwarf (COD), using standardized extraction procedures, was utilized for studying their storage behaviour under four different low-temperature regimes, i.e. 4ºC, -20ºC, -45ºC and -196ºC along with control at room temperature. Data on pollen germination percentage and pollen tube lengths were collected based on in vitro procedures at four different storage intervals (1st day, 14th day, 30th day and 60th day) to identify best short-term storage temperature. Germination percentage of pollen gradually reduced with duration of storage in all treatments but in case of pollen, which was stored at room temperature (control, i.e. 28±2ºC), viability decreased drastically and became nil within two weeks. Results revealed that higher germination percentage (38.82%) and pollen tube length (535.9 μm) were observed at -196ºC followed by -45ºC (31.77%, 400.73 μm) and -20ºC (30.82%, 282.89 μm) after a storage period of eight weeks. This study shows that desiccated pollen grains can be successfully stored at -45ºC for its utilization in breeding programmes besides long term storage at -196ºC.

2 Degree Of Freedom(2DOF) Ball Balancer system is a highly nonlinear system where the position of the ball is controlled by controlling two servo motors simultaneously. This system is an advanced version of ball and beam system 1 Degree Of Freedom (1 DOF). The physical significance of the ball balance system are pan and tilt cameras for surveillance and satellite position correction. In general conventional PID controller is used in order to control the position of ball on plate in both axes (X, Y). PID controller is used to obtain an acceptable satisfactory response of the system. However, an exact nonlinear compensator is included to assure the closed-loop system stability. The major issue of conventional PID cannot give good eliminated results when external disturbance is more. This problem can be improvised by implementing Disturbance observer enhanced PD or PID controller(DOB). In this work the performance of Disturbance observer(DOB) enhanced PD controller is compared with the conventional PD controller response. In DOB enhanced PD the observer used is the inverse of the system transfer function and it observes the externally applied disturbance and make the system response to perform better in an environment prone to disturbances. The results are illustrated via simulation. [ABSTRACT FROM AUTHOR]