Cassava (Manihot esculenta Crantz) roots (tubers) are used as staple food. Starch extracted from tubers is widely utilized as raw materials in industries. Dry matter (DM) content, starch and flour extraction and proximate composition were investigated in seven cassava accessions (Coc-A 1, Kh-A 2, Cow-A 3, Sa-A 4, Me-A 5, Va-A 6 and Sy-A 8. ) in 2010-2011. Leaf DM varied from 20.51% in Me-A 5 to 29.01% in Sy-A 8 ; that of stem from 27.24% in Va-A 6 to 32.10% (average of Sy-A 8 , Me-A 5 and Sa-A 4 ); and that of tuber from 37.30% in Kh-A 2 to 45.26% in Sy-A 8 . Starch was extracted by blending chopped tuber followed by decantation. Tubers were sliced, sun dried and milled into flour. Tuber starch content (fresh wt. basis) varied between 15.04% in Sy-A 8 and 24.97% (average of Coc-A 1 and Me-A 5 ); that of peel from 4.54% in Va-A 6 to 5.85% in Coc-A 1 . Crude protein varied from 1.80% (average of Kh-A 2 , Cow-A 3 and Sy-A 8 ) to 4.53% in Va-A 6 . Crude fiber content varied from 1.95% (average of Sa-A 4 and Coc-A 1 ) to 4.27% in Cow-A 3 . Cyanogens present in cassava plant escape as hydrogen cyanide (HCN) during harvesting and processing. Variation for HCN existed and it was 140.95 mg/kg fresh tuber (average of Sy-A 8 and Coc-A 1 ) to 546.0 mg/kg fresh tuber in Va-A 6 . There was no detectable HCN in the extracted flour and starch. It may be concluded that genetic variation for DM, starch, protein and HCN existed in seven cassava accessions, and Coc-A 1 may be a better one due to its lower HCN, higher DM and starch content.

Temperature is considered as an important environmental factor, and the increasing water temperature resulting from global warming is a great concern. The present study was conducted to examine the effects of elevated water temperature on growth, hemato‐biochemical parameters in Nile tilapia, Oreochromis niloticus acclimatized to three temperatures (31°C, 34°C and 37°C) for 60 days. Additionally, erythrocytic cellular abnormalities (ECA) and erythrocytic nuclear abnormalities (ENA) tests were assayed using peripheral erythrocytes after exposure to the three temperatures. Fish were sacrificed on days 7, 15, 30 and 60 of exposure. Growth performances viz., weight gain, % weight gain and specific growth rate (SGR) showed decreasing tendency at 34°C but significantly declined at 37°C compared to 31°C. The abundance of haemoglobin (Hb) and red blood cells (RBCs) significantly decreased in response to temperature increases, while white blood cells (WBCs) displayed the opposite response. At days 7 and 15, blood glucose levels significantly increased in response to the temperature increase, while at days 30 and 60 glucose declined. Frequencies of ECA and ENA were significantly enhanced at the highest temperature throughout the experimental period. Dissolved oxygen decreased and free CO2 increased significantly with increasing temperature throughout the study period. The present study revealed that temperatures higher than 34°C may be hazardous to O. niloticus.

An experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during June to December, 2013 to investigate the response of some short duration aman rice varieties to date of transplanting. The experiment consisted of three transplanting dates viz. 26 July, 5 August and 15 August and seven short duration T. aman rice varieties viz. BRRI dhan33, BRRI dhan39, BRRI dhan49, BRRI dhan56, BRRI dhan57, BRRI hybrid dhan4 and Binadhan-7. The experiment was laid out in split plot design with three replications. Transplanting dates were allocated into the main plot and varieties into the sub plot. Results indicate that Binadhan-7 produced the highest grain yield (4.90 t ha -1 ), straw yield (5.58 t ha -1 ), biological yield (10.44 t ha -1 ), and harvest index (47.10%). Lowest grain yield (3.27 t ha -1 ), straw yield (3.96 t ha -1 ) and biological yield (7.20 t ha -1 ) were produced by BRRI dhan57. BRRI dhan49 had taken the longest field duration (120 DAT) while BRRI dhan57 had taken the shortest field duration (88 DAT). Plant height (119.12 cm), number of total tillers m -2 (276.40), number of effective tillers m -2 (260.02), number of grains panicle -1 (109.19), grain yield (4.75 t ha -1 ), straw yield (5.22 t ha -1 ), biological yield (9.97 t ha -1 ) and harvest index (47.64%) were highest on 26 July transplanting; decreased on 5 August transplanting and drastically declined on 15 August transplanting. The present study concludes that the highest yield for short duration T. aman rice cultivation could be possible by Binadhan-7 transplanting on 26 July.

An experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh during the period from July to December 2012 to find out the effect of herbicide Prechlor 500 EC on weed control and performance of transplant aman rice. The experiment was laid out in a randomized complete block design with four replications. The experiment consisted of two varieties viz., BRRI dhan41 and Nizershail, and four levels of Prechlor @ 0, 0.5, 1.0 and 1.5 L ha -1. Monochoria vaginalis, Nymphaea nouchali, Paspalum scrobiculatum, Echinochloa crusgalli and Scirpus juncodies were the major weeds in the experimental plots. Prechlor 500EC @ 1.5 L ha -1 showed the best performance in reducing weed density, weed dry weight and increased weed control efficiency but reduce grain yield. Variety had significant influence on all the yield and yield contributing characters of rice. Higher grain yield (3.09 t ha . The results suggest that farmers can be advised to use herbicide Prechlor @ 1.5 L ha -1 to boost up the production of BRRI dhan41 controlling weeds during aman season under the agro-climatic condition of the study area.

An experiment was carried out at Bangladesh Agricultural University, Mymensingh to evaluate the effect of urea super granule (USG) as a source of nitrogen on the yield and yield components of transplant Aman rice cv. BRRI dhan39, BRRI dhan46 and BINA dhan7. Five levels of N (viz., 0, 60, 120 kg ha -1 as prilled urea and 60 and 120 kg ha -1 as USG) were taken as experimental treatments. The experiment was laid out in a randomized complete block design with three replications. Plant height, effective tillers hill -1 , grains panicle -1 and grain yield varied significantly due to different cultivars. All the yield and yield components except 1000-grain weight were influenced significantly by the levels of nitrogen fertilizer. The highest grain yield (4.82 t ha -1 ) was recorded in BINA dhan7 and the lowest one (4.30 t ha -1 ) was recorded in BRRI dhan39. Nitrogen @ 120 kg ha -1 as USG performed the best among the treatments in respect of yield and yield components of rice. The highest grain yield (5.46t ha -1 ) was obtained from BINA dhan7 with 120 kg N ha -1 as USG which was statistically identical with 60 kg N ha -1 as USG. A considerable amount (31.25%) of prilled urea (PU) nitrogen could be saved by using USG. It may be concluded that USG could be used as N management to achieve better nitrogen use efficiency in reducing N loss than the PU.