M.A. Alam
BangladeshSugarcane Research Instutite (BSRI), Bangladesh
M.M.H. Tipu
BangladeshAgricultural Research Instutite (BARI), Bangladesh
M.M.I. Chowdhury
BangladeshAgricultural Research Instutite (BARI), Bangladesh
M.H. Rubel
Noakhali Science & Technology University, Sonapur, Bangladesh
M. A. Razzak
BangladeshSugarcane Research Instutite (BSRI), Bangladesh
Rice, Row direction, Weeding regime, Yield
Bangladesh Agricultural University, Mymensingh
Crop-Soil-Water Management
Weed management
The experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during boro (dry) season starting from November 2010 to May 2011.The soil belongs to the Old Brahmaputra Floodplain agro-ecological zone, having non-calcareous dark grey floodplain soil [16].Soil in the experimental fields at 0–15-cm depth was silt loam in texture with pH of 6.2, organic carbon of 1.29%, sand of 32%, silt of 60%, and clay of 8%. The experiment consisted of ten weeding regimes, viz. T1= Rifit 500 EC @ 1.0 l ha-1, T2= Sibafit 500EC @ 1.0 l ha-1, T3= Rav 500EC @ 1.0 l ha-1, T4= Ichlor 5G @ 1.0 l ha-1, T5= Superhit 500EC @ 1.0 l ha-1, T6= Control (no weeding) T7= Weeding at 15 days interval, T8= One time hand weeding at 25 DAT, T9= Two times hand weeding at 25 and 45 DAT, T10= Two times hand weeding at 35 and 55 DAT and two row directions, viz. S1= East-West row direction, S2= North-South row direction. Herbicides used in the experiment were systemic and pre-emergence type.For the hand weeding treatment, one hand weeding was done on 25 DAT. In the case of two times hand weeding, one hand weeding treatment was done 25 DAT followed by second hand weeding at 45 DAT. For another two times hand weeding, one time hand weeding was done 35 DAT followed by second hand weeding at 55 DAT. For no weed control treatment weeds were allowed to grow in the plots from transplanting to harvesting of the crop. But in Weeding at 15 days interval treatment, plots were kept moderately weed free up to harvesting by hand weeding at 15 days interval.The experiment was laid out in a randomized complete block design. There were 20 treatment combinations. The treatments were replicated thrice. Each replication was divided into 20 unit plots where the treatment combinations were allocated at random. Thus the total number of unit plots was 60. The size of each unit plot was 4.0m ×2.5m. Distance maintained between unit plots and replications were 0.75 m and 1 m, respectively.Rice variety BRRI dhan29 was used as the experimental material. Seeds of BRRI dhan29 were collected from Bangladesh Rice Research Institute, Gazipur. The seeds were sown in the nursery bed on 02 December 2010 with appropriate care. Fertilizers were applied in the plots @ 120kg ha-1, 60kg ha-1, 40 kg ha-1 of N,P2O5 and K2O in the form of Urea, Triple Super Phosphate and Muriate of Potash, respectively. Gypsum and Zinc Sulphate were also applied @ 60kg ha-1 and 10 kg ha-1, respectively.The entire amount of TSP, MP, Gypsum and Zinc Sulphate was applied at final land preparation. Urea was top dressed in three equal splits at 15 days after transplanting (DAT), tillering stage and panicle initiation stage.Seedlings of 52 days old were uprooted carefully from the nursery bed and were transplanted on the well puddled experimental plots on 24 January 2011 at the rate of 3-4 seedling hill-1, maintained row and hill distance of 25 cm ×15 cm.Flood irrigation was given to maintain a level of standing water up to 2-4 cm until maximum tillering stage and after that, a water level of 7-10 cm was maintained up to grain filling stage and then drained out of the field after milk stage.The crop was harvested on 07 May 2011. The harvested plants were tied into bundles plot wise, then threshed, cleaned and dried in the Agronomy Field Laboratory to record the data on grain yield and straw yield. Prior to harvest five hills per plot were selected randomly (excluding border hills).They were uprooted carefully, cleaned and tagged properly. Data on different plant characters were recorded from the five hills plot-1and yields were taken from plot-wise harvest and eventually converted to t ha-1. The collected data were plant height, total tillers hill-1, effective tillers hill-1, panicle length, grains panicle-1, 1000-grain weight, grain yield and straw yield. The grain yield was adjusted at 14% moisture level. The data were analyzed statistically by using the ANOVA technique. The mean difference was adjudged by Duncan’s Multiple Range Test (Gomez and Gomez, 1984).
Research & Reviews: Journal of Crop Science and Technology ISSN: 2319-3395 (online) Volume 4, Issue 2www.stmjournals.com
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