agrotecnologia

Abstrato

Effect of Weed Control Methods on the Yield of Wheat

Md. Mohaiminul Islam, Mahfuza Begum, Md. Abdus Salam, Md. Azizur Rahman

An experiment was conducted at the agronomy field laboratory of Bangladesh agricultural university, Mymensingh, from November 2017 to March 2018 to assess the effect of weed control methods on weeds and yield of wheat (Triticum aestivum L.). The experiment was laid out in a Randomized Complete Block Design (RCBD) with four replications. Total treatment combination was 11. The treatments were T₀=unweeded, T₁=hand weeding at 25 DAS, T₂=hand weeding at 40 DAS, T₃=hand weeding at 25 and 40 DAS, T₄=Panida 33EC, T₅=Panida 33EC+hand weeding at 40 DAS, T₆=affinity 50.75WP as post emergence herbicide, T₇=affinity 50.75WP+hand weeding at 40 DAS, T₈=Panida 33EC+affinity 50.75WP, T₉=Panida 33EC+affinity 50.75+hand weeding at 40 DAS. A total of 18 weed species belonging to 13 families infested the experimental crops of which three from Poaceae, two from each of the family Solanaceae, Commeliaceae, Amaranthaceae and one from each of the family Cyperaceae, Chenopodiaceae, Brassicaceae, Apiaceae, Convolvulaceae, Polygonaceae, Fabaceae, Scrophulriaceae, Portulaceae and annual outnumbered the perennial. The rank of order of five most dominant weed species at 50 DAS and harvest was different. Polygonum hydropiper, Chenopodium album, Cyperus rotundus are common in all sampling and at harvest Cynodon dactylon, Amaranthus viridis were found instead of Dacus carota and Echinochola colonum at 50 DAS. Digitaria sanguinalis, Commelina diffusa, Amaranthus viridis, Portulacea oleracea newly appeared at harvest. Among all the weed control treatments except weed free T₉ produced lowest weed density and dry weight and highest value was found in unweeded condition. In regards of the crop characters T₉ treatment (Panida 33EC pre emergence herbicide+affinity 50.75+hand weeding at 40 DAS) produced highest number of plant height, number of total tillers hill^-1, number of effective tillers hill^-1, number of spikelets spike^-1, number filled grains spike^-1, grain yield, stover yield 107, 7.48, 6.945, 17.31, 46.67, 4.90 and 5.25 respectively. In unweeded condition highest yield loss (51.30%) was observed and lowest one found at T₉ treatment. Weed free condition is not economic for the crop production. After economic analysis the highest B: C ratio was found in treatment T₉. It means farmers become more benefited through applying this treatment. Therefore from the experiment it can be concluded that application of Panida 33EC+affinity 50.75WP +hand weeding at 40 DAS could be used as the best weed control practice in wheat cv. BARI gom-26.

An experiment was conducted at the agronomy field laboratory of Bangladesh agricultural university, Mymensingh, from November 2017 to March 2018 to assess the effect of weed control methods on weeds and yield of wheat (Triticum aestivum L.). The experiment was laid out in a Randomized Complete Block Design (RCBD) with four replications. Total treatment combination was 11. The treatments were T₀=unweeded, T₁=hand weeding at 25 DAS, T₂=hand weeding at 40 DAS, T₃=hand weeding at 25 and 40 DAS, T₄=Panida 33EC, T₅=Panida 33EC+hand weeding at 40 DAS, T₆=affinity 50.75WP as post emergence herbicide, T₇=affinity 50.75WP+hand weeding at 40 DAS, T₈=Panida 33EC+affinity 50.75WP, T₉=Panida 33EC+affinity 50.75+hand weeding at 40 DAS. A total of 18 weed species belonging to 13 families infested the experimental crops of which three from Poaceae, two from each of the family Solanaceae, Commeliaceae, Amaranthaceae and one from each of the family Cyperaceae, Chenopodiaceae, Brassicaceae, Apiaceae, Convolvulaceae, Polygonaceae, Fabaceae, Scrophulriaceae, Portulaceae and annual outnumbered the perennial. The rank of order of five most dominant weed species at 50 DAS and harvest was different. Polygonum hydropiper, Chenopodium album, Cyperus rotundus are common in all sampling and at harvest Cynodon dactylon, Amaranthus viridis were found instead of Dacus carota and Echinochola colonum at 50 DAS. Digitaria sanguinalis, Commelina diffusa, Amaranthus viridis, Portulacea oleracea newly appeared at harvest. Among all the weed control treatments except weed free T₉ produced lowest weed density and dry weight and highest value was found in unweeded condition. In regards of the crop characters T₉ treatment (Panida 33EC pre emergence herbicide+affinity 50.75+hand weeding at 40 DAS) produced highest number of plant height, number of total tillers hill^-1, number of effective tillers hill^-1, number of spikelets spike^-1, number filled grains spike^-1, grain yield, stover yield 107, 7.48, 6.945, 17.31, 46.67, 4.90 and 5.25 respectively. In unweeded condition highest yield loss (51.30%) was observed and lowest one found at T₉ treatment. Weed free condition is not economic for the crop production. After economic analysis the highest B: C ratio was found in treatment T₉. It means farmers become more benefited through applying this treatment. Therefore from the experiment it can be concluded that application of Panida 33EC+affinity 50.75WP +hand weeding at 40 DAS could be used as the best weed control practice in wheat cv. BARI gom-26.