165 research outputs found
Biometrical Study Of Brine Shrimp (Artemia franciscana) With Special Emphasis On Hatching Efficiency And Hatching Percentage In Tropical Condition At Bangladesh
The present study was carried out to investigate the hatching efficiency and hatching percentage of untreated and decapsulated cysts of Artemia franciscana at three salinities; 30 ppt, 35 ppt and 40 ppt. This study revealed that the hatching efficiency and hatching percentage were higher in case of decapsulated cysts. First hatching of nauplius from cysts were observed after 14 hours and 13 hours of incubation for untreated and decapsulated cysts, respectively. The values of hatching efficiency and hatching percentage were also higher at 35 ppt in untreated and decapsulated cysts. At 35 ppt, the hatching efficiency after 48 hours of incubation was 1.42× 105 for decapsulated cysts and the value for untreated cysts was 8.96× 104 nauplii per gram cysts. After 96 hours of incubation, the hatching percentage for decapsulated cysts were 75%, 89% and 90% at 30 ppt, 35 ppt and 40 ppt, respectively; and the values were 55%, 62.5% and 60% for untreated cysts at respected salinities, 30 ppt, 35 ppt and 40 ppt. The mean diameter for untreated and chorionic cysts were 242.2±1.90 µm and 213.5±3.167 µm respectively, with a chorionic thickness of 14.35 µm. This study would help the hatchery managers to understand the efficiency of larval live feed, since adequate data are lacking on the hatching performances of Artemia cysts in Bangladesh
Effect of phosphorus and potassium on the growth and yield of French bean
An experiment was conducted at the Agronomy Field Laboratory of the Department of Agronomy, Bangladesh Agricultural University, Mymensingh to investigate the yield response of French bean (Phaseolus vulgaris L.) as affected by phosphorus and potassium management. The experiment consisted of two factors. Factor A: Phosphorus fertilizer (4 levels) viz. P1=15Kg P ha-1, P2=20 Kg P ha-1 and P3=25 Kg P ha-1 , P4=35 Kg P ha-1 and factor B: Potassium fertilizer (4 levels) viz. K1=0 Kg K ha-1, K2=20 Kg K ha-1, K3=30 Kg K ha-1 and K4=40 Kg K ha-1. The variety BARI Jharsheem-3 was used in this experiment as the test crop. The experiment was laid out in a randomized complete block design (RCBD) with three replications. In case of phosphorus @ 25 kg ha-1 the highest number of pods plant-1 (4.96), pod length (13.34 cm), number of seeds pod-1 (4.54), weight of 1000-seed (431.21 g), seed yield (1.33 t ha-1), stover yield (1.53 t ha-1), biological yield (2.86 t ha-1) and harvest index 46.50% were found. In case of potassium @ 40 kg ha-1, he highest number of pods plant-1 (5.80), pod length (14.89 cm), number of seeds pod-1 (4.24), weight of 1000-seed (430.37 g), seed yield (1.53 t ha-1 ), stover yield (1.46 t ha-1 ), biological yield (2.99 t ha-1) and harvest index 51.17% were found. Interaction effect of phosphorus and potassium the highest number of pods plant-1 (5.18), pod length (13.40 cm), number of seeds pod-1 (4.30), weight of 1000-seed (430.53 g), seed yield (1.40 t ha-1 ), stover yield (1.60 t ha-1 ), biological yield (3.00 t ha-1 ) and harvest index 46.66% were recorded from P @ 25 kg ha-1 and K @ 40 kg ha-1. However, from the study it can be concluded that application of P @ 25 kg ha-1 and K @ 40 kg ha-1 was the most suitable combination for better yield of French bean
Average nucleotide identity of genome sequences supports the description of Rhizobium lentis sp. nov., Rhizobium bangladeshense sp. nov. and Rhizobium binae sp. nov. from lentil (Lens culinaris) nodules
Rhizobial strains isolated from effective root nodules of field-grown lentil (Lens culinaris) from different parts of Bangladesh were previously analysed using sequences of the 16S rRNA gene, three housekeeping genes (recA, atpD and glnll) and three nodulation genes (nodA, nodC and nodD), DNA fingerprinting and phenotypic characterization. Analysis of housekeeping gene sequences and DNA fingerprints indicated that the strains belonged to three novel clades in the genus Rhizobium. In present study, a representative strain from each clade was further characterized by determination of cellular fatty acid compositions, carbon substrate utilization patterns and DNA DNA hybridization and average nucleotide identity (ANI) analyses from whole-genome sequences. DNA DNA hybridization showed 50-62 % relatedness to their closest relatives (the type strains of Rhizobium etli and Rhizobium phaseoh) and 50-60 % relatedness to each other. These results were further supported by ANI values, based on genome sequencing, which were 87-92 % with their close relatives and 88-89 % with each other. On the basis of these results, three novel species, Rhizobium lentis sp. nov. (type strain BLR27(T)=LMG 28441(T)=DSM 29286(T)), Rhizobium bangladeshense sp. nov. (type strain BLR175(T)=LMG 28442(T)=DSM 29287(T)) and Rhizobium binae sp. nov. (type strain BLR195(T)=LMG 28443(T)=DSM 29288(T)), are proposed. These species share common nodulation genes (nodA, nodC and nodD) that are similar to those of the symbiovar viciae
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