Bangladesh Agron. J. 2018, 21(2): 87-95 EFFECT OF AQUEOUS EXTRACT OF SORGHUM CROP RESIDUES ON WEED MANAGEMENT AND CROP PERFORMANCE OF WHEAT F. Ahmed, M.R. Uddin*, M.D. Hossain, U.K. Sarker, D. Sarkar and D.N. Chadny Department of Agronomy, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh *Corresponding Author, Email: romijagron@bau.edu.bd (Received: 12 February 2019, Accepted: 10 April 2019) Keywords: Wheat varieties, number of weeds, inhibition (%), yield and harvest index (%) Abstract An experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh to evaluate the effect of aqueous extract of sorghum crop residues on weed management and crop performance of wheat. The experiment consisted of three varieties of wheat viz., BARI Gom-19, BARI Gom-21, BARI Gom-24 and five different levels of treatments such as no use of aqueous extract, aqueous extract of sorghum crop residues: 1:20 ratio (w/v), 1:30 ratio (w/v), 1:40 ratio (w/v) and hand weeding. The experiment was laid out in a randomized complete block design with three replications. Seven weed species belonging to five families infested the experimental plots. Weed population, weed dry weight and percent inhibition of weed were significantly influenced by aqueous extract of sorghum crop residues and varieties. The maximum weed growth was noticed with the variety BARI Gom-19 and the minimum was found in the variety BARI Gom-21. The grain yield as well as the other yield contributing characters produced by BARI Gom-21 was the highest among the studied varieties. The highest percent inhibition for all of the weeds was found in hand weeding treatment. The second highest percent weed inhibition was occurred in aqueous extract of sorghum crop residues @ 1:20 ratio (w/v) treatment which was 51.81, 51.10, 52.90, 55.58, 75.27, 73.83 and 53.85 percent for bathua (Chenopodium album), mutha (Cyperus rotundus), durba (Cynodon dactylon), biskatali (Polygonum hydropiper), angta (Paspalum scrobiculatum), tit begun (Solanum torvum) and shama (Echinochloa crusgalli) respectively. The highest loss of grain yield was obtained where no aqueous extract of sorghum crop residues were used. The highest yield and yield attributes were observed where hand weeding is done followed by the application of aqueous extract of sorghum crop residues @1:20 ratio (w/v). Wheat var. BARI Gom-21 with all treatments produced the highest grain and straw yield among the treatment combination. The results of this study indicate that different amount of aqueous extract of sorghum crop residues showed potential activity to suppress weed growth and it has significant effect on the yield of wheat. Therefore, aqueous extract of sorghum crop residues might be used as an alternative way for weed management in effective and sustainable crop production. Introduction Wheat (Triticum aestivum L.) is one of the world’s most commonly consumed cereal grains. In Bangladesh, wheat is the second most important cereal crop next to rice. Wheat yield in Bangladesh has increased with the introduction of high yielding varieties and by the use of weed controlling measurements. In mailto:romijagron@bau.edu.bd 88 Ahmed et al. 2015, average yield of wheat was estimated as 3.09 t ha-1 which was 1.75% higher than that of 2014 (BBS, 2015) But on an average grain yield is lower than many countries of the world. There are several reasons for yield losses in wheat but weed infestation is greater than the combined losses of insect pests and diseases and all other attributes. The traditional method of weed control is hand weeding which is very much laborious and time consuming. Herbicide is effective in controlling weeds alone or in combination with hand weeding but it is harmful for the nature (Ahmed et. al., 2005). Beside this another observation was that "herbicides in combination with hand weeding would help to obtain higher crop yield but it efforts high cost of production" (Prasad and Rafy, 1995; Sathyamoorthy et. al., 2004). With rising human health and ecological concerns about the adverse effects of indiscriminate use of farm chemicals research on alternative weed management methods is underway worldwide. Exploitation of allelopathic potential of different crop/plant species for weed management under field conditions is one such approach. Crop allelopathy controls weeds by the release of allele-chemicals from the living plants and/or through decomposition of phytotoxic plant residues (Belz, 2004; Khan et. al., 2005). Sorghum [Sorghum bicolor (L.) Monech] is one of the strongest allelopathic crops which have been extensively used as a cover crop or through incorporation of its residue in soil to control weed. Sorghum is a successful competitor against weeds in fields as empirically known. Sorghum seems to have some inhibiting effects on the growth of weeds. These suggest the allelopathic potential of sorghum and it will be very useful for biological control of weeds. Information regarding aqueous extract of sorghum crop residues for weed management is limited in our country. So, the study deserves to keep the significance in the current research interest in home and abroad about aqueous extract of sorghum crop residues having residual effects on weed control and yield performance to investigate the weed suppressing ability and to determine the optimum dose of aqueous extract of sorghum crop residues for the establishment of an easy, economic and sustainable method for efficient weed management and better yield of wheat. Materials and Methods The experiment was carried out at the Agronomy Field Laboratory of Bangladesh Agricultural University, Mymensingh from November 2016 to March 2017, located at 24°75' N latitude and 90°50' E longitude at an elevation of 18 m above the mean sea level characterized by non-calcareous dark grey floodplain soil belonging to the Old Brahmaputra Floodplain, (AEZ-9). The soil of the experimental field was more or less neutral in reaction with pH value 6.8, low in organic matter and fertility level. The land type was medium high with silty loam in texture. The experiment consists of two factors including crop residues (5) i) No use of extract (control), ii) Aqueous extract of sorghum crop residues @ 1:20 ratio (w/v), iii) Aqueous extract of sorghum crop residues @ 1:30 ratio (w/v), iv) Aqueous extract of sorghum crop residues @ 1:40 ratio (w/v) and v) Hand weeding and wheat variety (3): i) BARI Gom-19 (Sourav) ii) BARI Gom-21 (Shatabdi) iii) BARI Gom-24 (Prodip). The seeds were sown on 21 November, 2016 as per treatment specifications. The experiment was laid out in a randomized complete block design with three replications. Thus total numbers of plots were 45. Each plot size was (2 m2.5 m). The distance maintained between the individual plots was 0.5 m and the distance between the replication was 1.0 m. Effect of Aqueous Extract of Sorghum Crop Residues on Weed 89 100 controlat weedof Dry weight treatmentfrom weedof Dry weight-controlat weedof Dry weight × After collection, the crop residues were dried under shade in the covered threshing floor of Agronomy Field Laboratory of BAU. The studied crop residues were cut as small as possible by using sickle. The small pieces of sorghum crop residues were dipped into water for 24 hours and then collected the aqueous extract from residues. The prepared sorghum aqueous extract was applied two times (20 days and 40 days) after seed sowing by a hand sprayer and harvesting was done in 8th march, 2017. Data were collected on the basis of different parameters of wheat and weeds. Among them percent inhibition shows the suppressing ability of aqueous extract of sorghum residues on weed. Inhibition (%) = Data were also collected from wheat on yield basis such as grain yield, straw yield, harvest index etc which showed the yield performance of wheat. The recorded data were compiled and tabulated for statistical analysis. Analysis of variance was done with the help of computer package, MSTAT-C program. The mean differences among the treatments were adjudged by Duncan’s Multiple Range Test. Results and Discussion Infested weed species in the experimental field Seven weed species belonging to five families infested the experimental field. Local name, scientific name, family, morphological type and life cycle of the weed in the experimental plot have been presented in Table 1. Table 2. Effect of variety on number and percent inhibition on different weeds Number of weed per quadrate (25 x 25) cm2 % Inhibition Weed name Bathua Mutha Biskatali Durba Tit begun Shama Angta Bathua Mutha Biskatali Durba Tit begun Shama Angta variety v1 6.11 5.86 7.33b 6.13 0.80b 6.80a 1.00a 36.78c 40.06a 38.45b 39.40 47.51b 37.38 53.9 1b v2 5.86 5.53 7.53a 6.07 1.00a 6.26b 0.80b 38.97a 38.40b 39.62a 40.56 54.15a 39.29 58.1 9a v3 6.13 5.80 7.53a 6.27 1.00a 6.60ab 1.00a 37.80b 37.42b 38.49b 40.60 52.53a 38.09 54.2 5b Sx� 0.10 0.12 0.05 0.08 0.02 0.13 0.03 0.27 0.36 0.33 0.38 1.31 0.89 0.72 CV (%) 6.72 6.88 2.67 5.16 5.70 7.87 9.32 2.81 3.57 3.29 3.66 9.80 8.94 5.01 V1 = BARI Gom-19 (Sourav), V2 = BARI Gom-21 (Shatabdi), V3 = BARI Gom-24 (Prodip) Effect of variety on number and percent inhibition on different weeds Variety shows the significant effect on number of weed population for biskatali, tit begun, shama and angta and others are not significantly affected. The lowest number of weeds was found in different varieties for different weeds (Table 2). On the other hand only shama and durba are not significant and rest of them are significantly affected in terms of percent inhibition. Bathua (38.97), tit begun (54.15), biskatali (39.62) and angta (58.19) shows highest percent inhibition for V2 and mutha (40.06) is found in V1 variety. (Table 2) Table 1. Infested weed species found growing in the experimental plots in Wheat 90 Ahmed et al. Sl. No. Local name Scientific name Family Morphological type Life cycle 1 Mutha Cyperus rotundus Cyperaceae Sedge Perennial 2 Durba Cynodon dactylon Poaceae Grass Perennial 3 Bathua Chenopodium album Chenopodiaceae Broad leaved Annual 4 Shama Echinochloa crusgalli Gramineae Grass Annual 5 Angta Paspalum scrobiculatum Gramineae Grass Annual 6 Tit begun Solanum torvum Solanaceae Broad leaved Perennial 7 Biskatali Polygonum hydropiper Polygonaceae Broad leaved Annual Effect of aqueous extract of sorghum on number and percent inhibition on different weeds Numbers of weed populations are significantly affected by the treatments for all weed species. Lowest weed population was found in C4 treatments (Hand weeding) followed by C1 treatment (Table 3). Highest percent inhibition was also found in C4 treatment which is followed by C1 treatment where the concentration of aqueous extract of sorghum was high (1:20). Numerically 51.81, 51.10, 55.58, 52.90, 73.83, 53.85 and 75.26 percent inhibition were found in bathua, mutha, biskatali, durba, tit begun, shama and angta respectively for C1 treatment. (Table 3) Table 3. Effect of aqueous extract of sorghum on number and percent inhibition on different weeds Number of weed per quadrate (25 × 25) cm2 % Inhibition Weed name Bathua Mutha Biskatali Durba Tit begun Shama Angta Bathua Mutha Biskatali Durba Tit begun Shama Angta Treatments CO 8.78a 8.33a 11.00a 8.77a 1.99a 9.55a 2.00a 0.00e 0.00e 0.00e 0.00e 0.00e 0.00e 0.00e C1 5.11d 4.66d 6.44c 5.66d 0.67c 5.33d 0.55d 51.81b 51.10b 55.58b 52.90b 73.83b 53.85b 75.26b C2 6.66 c 5.99c 7.66b 6.44c 0.67c 7.33c 0.89c 35.56c 41.11c 40.50c 40.20c 56.12c 38.26c 62.73c C3 7.55b 7.55b 7.66b 7.22b 1.22b 8.00b 1.22b 23.32d 22.67d 31.96d 30.48d 32.54d 24.42d 39.25d C4 2.07 e 2.11e 4.55d 2.66e 0.11d 2.55e 0.00e 78.57a 78.19a 66.21a 77.32a 94.48a 76.01a 100.0a Sx� 0.13 0.13 0.07 0.11 0.02 0.17 0.03 0.35 0.46 0.43 0.49 1.68 1.14 0.93 CV (%) 6.72 6.88 2.67 5.16 5.70 7.87 9.32 2.81 3.57 3.29 3.66 9.80 8.94 5.01 In a column, figures with the same letter do not differ significantly as per DMRT. C0 = No use of extract, C1 = Aqueous extract of sorghum crop residues @ 1:20 ratio (w/v), C2 = Aqueous extract of sorghum crop residues @ 1:30 ratio (w/v), C3 = Aqueous extract of sorghum crop residues @ 1:40 ratio (w/v), C4 = Hand weeding Combined effect of variety and aqueous extract of sorghum on number and percent inhibition on different weeds For all the weed species V2C4 combination was found the lowest number of weed population. On the other hand highest percent inhibition was also found in the same combination. (Table 4) Table 4. Combined effect of variety and aqueous extract of sorghum on number and percent inhibition on different weeds Effect of Aqueous Extract of Sorghum Crop Residues on Weed 91 Number of weed per quadrate (25 × 25) cm2 % Inhibition Weed name Bathua Mutha Biskatali Durba Tit begun Shama Angta Bathua Mutha Biskatali Durba Tit begun Shama Angta Treatments V1C0 8.66ab 8.00abc 11.00b 8.33b 1.33b 10.33 2.00a 0.00 0.00g 0.00f 0.00h 0.00 0.00 0.00g V1C1 4.66g 4.667f 6.66g 6.33e 0.67d 5.33 0.67d 50.13 51.49b 54.61c 51.40d 71.85 53.09 72.43c V1C2 7.33d 6.66d 6.67g 6.33e 0.67d 7.33 1.00c 34.16 45.79c 40.23d 40.45ef 50.32 37.77 60.32d V1C3 7.66cd 7.66bc 8.00 e 7.00cd 1.00c 8.33 1.33b 23.08 25.68e 32.10e 30.13g 31.93 22.65 36.78f V1C4 2.23h 2.33g 4.33j 2.66gh 0.33e 2.66 0.00f 76.54 77.31a 65.32b 74.91b 83.44 74.66 100.0a V2C0 8.33bc 8.33ab 11.67a 9.00a 2.33a 9.00 2.00a 0.00 0.00g 0.00f 0.00h 0.00 0.00 0.00g V2C1 5.00fg 4.67f 6.67g 5.33f 0.67d 5.33 0.33e 53.29 51.76b 56.58c 55.14c 75.04 55.18 80.52b V2C2 6.33e 5.33f 7.67ef 6.33e 0.67d 7.00 0.67d 37.18 39.81d 40.62d 38.39f 60.30 39.05 64.17d V2C3 7.66cd 7.33c 7.67ef 7.33c 1.33b 7.66 1.00c 23.68 21.20f 31.44e 29.47g 35.41 25.75 46.26e V2C4 2.00h 2.00g 4.00j 2.33h 0.00f 2.33 0.00f 80.72 79.20a 69.44a 79.78a 100.0 77.84 100.0a V3C0 9.33a 8.66a 10.33c 9.00a 2.33a 9.33 2.00a 0.00 0.00g 0.00f 0.00h 0.00 0.00 0.00g V3C1 5.66ef 4.66f 6.00h 5.33f 0.67d 5.33 0.67d 52.01 50.19b 55.56c 52.07d 74.61 53.28 72.83c V3C2 6.33e 6.00e 8.66d 6.66de 0.67d 7.66 1.00c 35.33 37.74d 40.66d 41.80e 57.75 37.97 63.71d V3C3 7.33d 7.66bc 7.33f 7.33c 1.33b 8.00 1.33b 23.21 21.09f 32.35e 31.83g 30.29 24.85 34.72f V3C4 2.00h 2.00g 5.33i 3.00g 0.00f 2.66 0.00f 78.45 78.06a 63.88b 77.28b 100.0 75.53 100.0a Sx̅ 0.25 0.29 0.12 0.18 0.03 0.29 0.05 0.61 0.79 0.74 0.85 2.90 1.99 1.60 CV (%) 6.72 6.88 2.67 5.16 5.70 7.87 9.32 2.81 3.57 3.29 3.66 9.80 8.94 5.01 In a column, figures with the same letter do not differ significantly as per DMRT. V1 = BARI Gom-19 (Sourav), V2 = BARI Gom-21 (Shatabdi), V3 = BARI Gom-24 (Prodip) C0 = No use of extract, C1 = Aqueous extract of sorghum crop residues @ 1:20 ratio (w/v), C2 = Aqueous extract of sorghum crop residues @ 1:30 ratio (w/v), C3 = Aqueous extract of sorghum crop residues @ 1:40 ratio (w/v), C4 = Hand weeding Effect of variety on yield and yield contributing characters of wheat Varietal effect on yield and yield contributing characters of wheat showed the significant effect. Highest plant height, higher number of total tillers and effective tillers hill-1, higher number of grain spike-1, higher number of filled grain spike-1, highest straw yield and highest harvest index was found in V2 (BARI Gom-21) variety (Table 5).The highest grain yield (3.84 t ha-1) was obtained in BARI Gom-21 followed by BARI Gom-24 (3.69 t ha-1). (Fig. 1) Table 5. Effect of variety on yield and yield contributing characters of wheat Varieties Plant height (cm) No. of total tillers hill–1 No. of effective tillers hill–1 Panicle length (cm) No. of grains spike-1 Filled grain spike–1 1000- grain weight (gm) Straw yield (t ha–1) Harvest index (%) V1 88.71c 4.02b 3.16b 10.29 42.23 15.22b 55.18a 4.01b 45.14b V2 95.51a 4.13a 3.35a 10.46 43.36 15.75a 53.60ab 4.36a 46.75a V3 91.24b 4.07ab 3.25b 10.36 42.76 15.42ab 52.39b 4.35a 45.57b Sx� 0.761 0.023 0.032 0.105 0.385 0.141 0.606 0.037 0.348 CV (%) 3.21 2.14 3.85 3.92 3.48 3.53 4.37 3.40 2.94 In a column, figures with the same letter do not differ significantly as per DMRT. V1 = BARI Gom-19 (Sourav), V2 = BARI Gom-21 (Shatabdi), V3= BARI Gom-24 (Prodip) 92 Ahmed et al. Fig. 1. Grain yield as influenced by variety (Bar represents standard error mean) Here, V1 = BARI Gom-19 (Sourav), V2 = BARI Gom-21 (Shatabdi), V3 = BARI Gom-24 (Prodip) Effect of aqueous extract of sorghum crop residues on yield and yield contributing characters of wheat Aqueous extract of sorghum crop residues had also significant effect on yield and yield contributing characters. The highest grain yield (3.97 t ha-1) was produced by C4 treatment, followed by C1 (3.88 t ha -1) and lowest one (2.61 t ha-1) was produced by C0 (no use of extract) treatment due to the production of higher number of effective tillers hill-1, higher number of grain spike-1, higher number of filled grain spike-1. The lowest grain yield was produced in C0 treatment. (Table 6 and Fig. 2). Uddin and Pyon (2010) also reported the similar results, where crop residues influenced in crop performance. Table 6. Effect of aqueous extract of sorghum crop residues on yield and yield contributing characters of wheat Residues Plant height (cm) No. of total tillers hill–1 No. of effective tillers hill–1 Panicle length (cm) No. of grains spike-1 Filled grain spike–1 1000 grain weight (gm) Straw yield (t ha–1) Harvest index (%) C0 82.27d 3.46d 2.70e 9.57c 39.72d 13.28d 51.27b 3.51c 42.12b C1 94.92b 4.21b 3.41b 10.58ab 44.08b 16.24b 53.27b 4.29b 47.48a C2 92.75bc 4.13b 3.29c 10.49b 42.62c 15.42c 53.44b 4.40ab 46.60a C3 91.02c 4.02c 3.13d 10.28b 41.02d 15.05c 52.96b 4.43ab 46.23a C4 98.14a 4.54a 3.72a 10.92a 46.54a 17.34a 57.66a 4.54a 46.67a Sx� 0.983 0.030 0.042 0.135 0.497 0.182 0.782 0.048 0.450 Level of significance ** ** ** ** ** ** ** ** ** CV (%) 3.21 2.14 3.85 3.92 3.48 3.53 4.37 3.40 2.94 ** =Significant at 1% level of probability. C0 = No use of extract, C1 = Aqueous extract of sorghum crop residues @ 1:20 ratio (w/v), C2 = Aqueous extract of sorghum crop residues @ 1:30 ratio (w/v), C3 = Aqueous extract of sorghum crop residues @ 1:40 ratio (w/v), C4 = Hand weeding. 0 1 2 3 4 5 V1 V2 V3 Variety Gr ain yi eld (t h a–1 ) Effect of Aqueous Extract of Sorghum Crop Residues on Weed 93 Fig. 2. Grain yield as influenced by aqueous extract of sorghum crop residues (Bar represents standard error mean) C0 = No use of extract, C1 = Aqueous extract of sorghum crop residues @ 1:20 ratio (w/v), C2 = Aqueous extract of sorghum crop residues @ 1:30 ratio (w/v), C3 = Aqueous extract of sorghum crop residues @ 1:40 ratio (w/v), C4 = Hand weeding Combined effects of variety and aqueous extract of sorghum crop residues on yield and yield contributing characters of wheat Yield and yield contributing characters like straw yield and grain yield were significantly affected by the interaction between variety and crop residues. V2C4 combination showed the maximum result which was followed by V3C1. (Table 7) Table 7. Combined effects of variety and aqueous extract of sorghum crop residues on yield and yield contributing characters of wheat Variety x Residues Plant height (cm) No. of total tillers hill–1 No. of effective tillers hill–1 Spike length (cm) No. of grain spike-1 No of spikelet spike–1 1000 grain weight (gm) Grain yield (t ha–1) Straw yield (t ha–1) Harvest index (%) V1C0 80.73 3.40 2.57 9.55 39.26 12.94 55.07 2.16i 3.11g 41.00 V1C1 90.73 4.13 3.33 10.48 43.64 16.10 53.12 3.63ef 4.24cde 46.10 V1C2 89.87 4.10 3.20 10.41 42.11 15.33 55.90 3.59f 4.16de 46.34 V1C3 88.70 4.03 3.05 10.22 40.46 14.67 55.73 3.52f 4.15de 45.92 V1C4 93.53 4.43 3.63 10.81 45.67 17.05 56.07 3.77de 4.36bcd 46.35 V2C0 83.72 3.45 2.83 9.59 40.04 13.78 49.56 2.95g 3.82f 43.46 V2C1 99.69 4.27 3.53 10.72 44.86 16.47 53.54 4.08ab 4.09e 46.88 V2C2 96.49 4.17 3.40 10.59 42.95 15.51 52.87 4.03abc 4.57ab 46.86 V2C3 94.03 4.00 3.17 10.35 41.45 15.40 52.18 4.02abc 4.61ab 46.58 V2C4 104.48 4.67 3.80 11.04 47.47 17.60 59.83 4.13a 4.69a 46.84 V3C0 82.37 3.43 2.70 9.57 39.85 13.23 49.19 2.73h 3.59f 41.22 V3C1 94.40 4.23 3.37 10.56 43.74 16.23 53.15 3.95bc 4.56ab 46.40 V3C2 91.90 4.13 3.27 10.47 42.81 15.41 51.55 3.90bcd 4.48abc 46.58 V3C3 90.33 4.03 3.20 10.26 41.14 15.08 50.95 3.88cd 4.52ab 46.22 V3C4 97.20 4.53 3.73 10.95 46.29 17.30 57.09 4.02abc 4.57ab 46.82 Sx� 1.70 0.050 0.072 0.234 0.861 0.315 1.35 0.055 0.084 0.779 Level of significance NS NS NS NS NS NS NS * ** NS CV (%) 3.21 2.14 3.85 3.92 3.48 3.53 4.37 2.61 3.40 2.94 ** =Significant at 1% level of probability, * =Significant at 5% level of probability, NS = Non significant 0 1 2 3 4 5 C0 C1 C2 C3 C4 Crop residues Gr ain yi eld (t h a–1 ) 94 Ahmed et al. V1 = BARI Gom-19 (Sourav), V2 = BARI Gom-21 (Shatabdi), V3 = BARI Gom-24 (Prodip) C0 = No use of extract, C1 = Aqueous extract of sorghum crop residues @ 1:20 ratio (w/v), C2 = Aqueous extract of sorghum crop residues @ 1:30 ratio (w/v), C3 = Aqueous extract of sorghum crop residues @ 1:40 ratio (w/v), C4 = Hand weeding Conclusion From the above results it was found that the wheat var. BARI Gom-21 with C4 (hand weeding) treatment exhibited the superior effect and BARI Gom-21 with C1 showed quite close result with it. Results of the present study reveal that application of aqueous extract of sorghum crop residues has positive effect on yield for most of the studied traits. It also shows that aqueous extract of sorghum crop residues have herbicidal activity for suppressing weed growth and there is immense prospect of sorghum crop residues as a weed management tool. 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