On-farm Evaluation and System Productivity of Wheat-Jute-T. aman Rice Cropping Pattern in Char Area of Bangladesh

A study was conducted for two consecutive years to determine the yield and system productivity of two cropping patterns viz. IP: (Wheat - Jute - T. aman) improved pattern with improved management practices and FP: (Fallow - Fallow - T. aman) farmers’ pattern with farmers’ management practices in char (adjacent to the river) area of Netrakona region of Bangladesh. The experimentswere laid out in a randomized complete block design with 10 dispersed replications at a farmer’s field. The two years mean data showed that the total component crops of IP (wheat-jute-T. aman rice) gave higher yield as well as a by-product in both years. The higherrice equivalent yield (10.52 and 10.63 tha-1), production efficiency (30.13 and 30.43 kg ha-1 day-1) land-use efficiency (87.13 and 87.84%)and benefit cost ratio (2.15 and 2.11) pointed out the dominance of the improvedpattern over the farmer’s existing pattern. Higher rice equivalentyield signified that improved cropping pattern (Wheat - Jute -T. aman) could be appropriate in Netrakona region for rising crop productivity andcropping intensity.The higher production efficiency, land use efficiency and benefit cost ratio indicated the superiority of the improved pattern over the farmers’ practices.It can be concluded that farmers of the char area of the Netrakona region might follow wheat (var. BARI Gom-26) - jute (var. O-9897) - T. aman (var. BRRI dhan49) cropping system in char land for higher productivity and profitability

Reduction in use of herbicides by combining aqueous extract of grass pea for weed management and yield of wheat

Nowadays, the increasing costs in the agricultural sector, increasing public concern about the widespread use of herbicides and the development non-chemical methods of weed control programs are alerting management. In this regard, an experiment was conducted to evaluate the effect of aqueous extract of grass pea residues on weed management and crop performance of wheat. The experiment was comprised of three varieties of wheat viz., BARI Gom-30, BARI Gom-31, BARI Gom-32 and six different levels of treatments such as no weeding, recommended dose of herbicide, aqueous extraction of grass pea, 90% recommended dose + aqueous extraction of grass pea,80% recommended dose + aqueous extraction of grass pea, 70% recommended dose +aqueous extraction of grass pea, 60% recommended dose + aqueous extraction of grass pea. The experiment was laid out in a randomized complete block design with three replications. Weed population, weed dry weight and weed control efficacy were significantly influenced by aqueous extract of grass pea crop residues and varieties. The highest numbers of tillers hill-1, numbers of grains spike-1, 1000 grain weight and grain yield were observed where recommended dose of herbicide was used followed by the application of 90% recommended dose +aqueous extraction of grass pea. BARI Gom-31along with 90% recommended dose +aqueous extraction of grass pea produced the highest grain and straw yield among the treatment combination. Therefore, aqueous extract of grass pea crop residues might be used as an alternative way for weed management in effective and sustainable crop production

Nitrogen management in boro rice using chlorophyll meter (SPAD) under sub-tropical condition

Nitrogen deficiency in rice has so far received limited attention in Bangladesh. Balanced fertilization is a pre-requisite for better rice production and it is necessary to determine optimum combination of fertilizer dose and varieties. The field experiment was carried out during the period from November 2020 to May 2021 at the Agronomy Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh to study the SPAD value and yield performance of boro rice varieties at different nitrogen levels. The experiment comprised of four boro rice varieties viz., BRRI dhan28, BRRI dhan58, BRRI dhan74, BRRI dhan81 and four level of nitrogenous fertilizers viz. 50 kg N ha-1, 100 kg N ha-1, 150 kg N ha-1 and 200kg N ha-1. The experiment was laid out in a randomized complete block design with three replications. SPAD value ranged from 34.01 to 42.12 for variety and 37.81 to 42.15 for nitrogen application, while leaf nitrogen ranged from 2.98 to 3.67 % for variety and 2.94 to 3.48%.  The yield contributing parameter varied significantly with variety and nitrogen rate. The highest grain yield (6.13 t ha-1) was found in BRRI dhan58 and the lowest (3.89 t ha-1) was observed in BRRI dhan28. In terms of fertilizer management, the highest grain yield (5.35 t ha-1) was obtained due to the application of 150 kg N ha-1 and the lowest grain yield (4.72 t ha-1) was recorded from50 kg N ha-1. The interactive effect of variety and fertilizer application exerted that the yield of BRRI dhan58 with 150 kg N ha-1 was the highest (6.59 tha-1) and the lowest performance (3.42 tha-1) in grain yield was found in BRRI dhan28 with 50 kg N ha-1. Thus, the variety BRRI dhan58 with 150 kg N ha-1 was superior for attaining the highest yield

Floristic divergence of weeds in rice fields under subtropical condition

Weed infestation pattern changes over time for continuous adaptation of similar weed control methods. So, a survey was conducted at Agronomy Field Laboratory, Bangladesh Agricultural University from July 2019 to June 2020 to identify the most dominant and abundant weed species as well as to indicate the probable problematic weed in boro and T. aman rice. Seven fields were randomly selected for each of the boro and T. aman rice. The surveys were performed according to quantitative survey technique by using 0.25m2 quadrate with 16 samples from each of the field following the zig-zag method. Sampling was done twice, while the rice plants were at the vegetative stage and at reproductive stage. Fifty one weed species under 23 families were recorded at experimental area of which 42 species (under 18 families) and 38 species (under 20 families) were observed in boro and T. aman, respectively. Poaceae topped the list with 10 species, while Cyperaceae ranked second with six species. The highest number of weed species (no. 42) was observed in boro rice compared to T. aman rice (no. 38). Besides, divergence in the weed composition was also high between both rice fields. Among the 11 abundant weed species, Eleocharis atropurpurea, Echinochloa crusgalli and Monochoria vaginalis were the most frequent and abundant weed species found in both boro rice and T. aman rice. Broadleaves had higher abundance value (246.26% in boro and 332.39% in T. aman) than grasses (188.76% in boro and 146.68% in T. aman) and sedges (164.98% in boro and 120.93% in T. aman). Moreover, the annuals were dominant over the perennials. Therefore, the present results having diversified weed species with different ranks and orders indicated that the weed management strategies should be taken regarding the infestation of dominant weed species of the respective crop

Phenolic compound production by different morphological phenotypes in hairy root cultures of Fagopyrum tataricum Gaertn.

Hairy roots were obtained after inoculating sterile young stems of Fagopyrum tataricum with Agrobacterium rhizogenes R1000. The established roots displayed two morphological phenotypes when cultured on hormone-free medium containing Murashige-Skoog salts and vitamins. The thin phenotype had a higher growth rate than the thick phenotype. Further, the phenolic compound content of the thin phenotype was higher than that of the thick phenotype. In terms of their total dry weight, the thin phenotype produced an almost double amount of (-)-epigallocatechin as well as more than 51.5% caffeic acid, 65% chlorogenic acid, and 40% rutin compared to the thick phenotype after 21 days of culture. Therefore, selection of the optimal morphological phenotype of hairy roots of tartary buckwheat is an important factor for improved phenolic compound production

Weed management and crop performance of rice as influenced by different crop residues

To investigate the effect of different plant residues on weed inhibition and yield of transplant aman rice, an experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during June 2017 to December, 2017. The experiment comprised of three rice cultivars i.e. BR11, BRRI dhan34 and BRRI dhan49 and five different plant residues treatment viz., no crop residues (control), soybean, wheat, bishkatali and sorghum crop residues @ 2.0 t ha-1 of each. The experiment was laid out following randomized complete block design with three replications. Weed population and weed dry weight were significantly affected by cultivars and crop residues treatment. The highest percent inhibition of 58.31%, 46.84%, 66.85%, 66.94% and 57.6% was in Panikachu (Monochoria vaginalis), Shama (Echinochloa crusgalli), Chesra (Scirpus juncoides), Sabujnakful (Cyperus difformis) and Amrul (Oxalis corniculata), respectively caused by sorghum crop residues. The grain yield, as well as the yield contributing characters produced by BR11,was the highest among the studied varieties. The highest number of effective tillers hill-1 (8.41), number of grains panicle-1(118.08) and 1000-grain weight (20.54 g) were observed in sorghum crop residues. BR11 under sorghum crop residues @ 2.0 t ha-1 produced the highest grain (5.76 t ha-1) and straw yield (6.39 t ha-1). So, to reduce herbicide use in the present situation of Bangladesh, natural herbicide or crop residues like sorghum might be used as an alternative way for weed management for effective and sustainable rice production

Combined allelopathic effect of buckwheat and marsh pepper residues on weed management and crop performance of transplant aman rice

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during the period from June to December 2016 to evaluate the suppression of weed growth through combined application of buckwheat and marsh pepper residues in transplant aman rice. The experiment consisted of three cultivars i.e. BRRI dhan56, Binadhan-12 and Nizershail, and five different crop residues with their combination such as no residues, 2.0 t ha-1 buckwheat residues, 2.0 t ha-1 marsh pepper residues, combined 0.5 t ha-1 buckwheat and 1.0 t ha-1 marsh pepper residues, combined 1.0 t ha-1 buckwheat and 0.5 t ha-1 marsh pepper residues. The experiment was laid out in a randomized complete block design with three replications. Weed population and weed dry weight were significantly affected by cultivars and crop residues treatment. The maximum weed growth was noticed with no residues treatment and the minimum was found in combined 0.5 t ha-1 buckwheat and 1.0 t ha-1 marsh pepper residues. The grain yield as well as the yield contributing characters produced at BRRI dhan 56 was the highest among the studied varieties. The highest reduction of grain yield was obtained in no residues) treatment and the lowest was obtained when combined 0.5 t ha-1 buckwheat and 1.0 t ha-1 marsh pepper residues were applied. The highest numbers of effective tillers hill-1, number of grains panicle-1, 1000-grain weight, and grain and straw yields were observed in W3 treatment. BRRI dhan56 under 0.5 t ha-1 buckwheat and 1.0 t ha-1 marsh pepper residues treatment produced the highest grain yield. Results of this study indicates that combination of 0.5 t ha-1 buckwheat and 1.0 t ha-1 marsh pepper residues showed potentiality to suppress weed growth. Therefore, crop residues could be used as an alternative tool for sustainable weed management

Effect of variety and sulphur on yield and yield components of groundnut

Variety and sulphur play a significant role in the physiological growth and yield of crops such as groundnut. Even so, there has been little information on the application of variety and sulphur in groundnut. Therefore, an experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh to investigate the effect of sulphur on yield and yield components of two groundnut varieties. The experiment comprised two varieties of groundnut viz. BARI Cheenabadam-8 and Bina cheenabadam-6; and five levels of sulphur viz. 0, 15, 30, 45, and 60 kg ha–1. The experiment was laid out in a randomized complete block design with three replications. Among the parameters leaf area index (2.03), dry matter plant–1 (50.36 g), number of primary branches plant–1 (10.33 cm), number of secondary branches plant–1 (9.27 cm), number of pegs plant–1 (46.27), number of total pods plant–1 (37.80), 100-pods weight (96.82 g), 100- seeds weight (46.25 g), shelling percentage (85.29%), pod yield (3.13 t ha–1), seed yield (2.67 t ha–1), stover yield (6.84 t ha–1), and harvest index (31.37 %) were the highest in BARI Cheenabadam-8, when treated with sulphur 60 kg ha–1. The lowest values of all these parameters were found in Binacheenabadam-6, when no sulphur was applied. This study suggested that BARI Cheenabadam-8 combined with sulphur 60 kg ha–1 could be applied for obtaining the highest yield of groundnut

Combined herbicidal effect of two natural products (sorgoleone and hairy root extract of tartary buckwheat) on crops and weeds

Abstract Sorgoleone, a root exudate of sorghum [(Sorghum bicolor (L.) Moench] and hairy root extract of tartary buckwheat (Fagopyrum tataricum Gaertn.) were mixed and applied to different broadleaf and grass weed species and crop species in the greenhouse arranging a randomized complete block design with four replications to evaluate their combined herbicidal activity and crop selectivity. A mixture of these two natural products (sorgoleone and root extract of tartary buckwheat) showed significantly greater inhibitory effects than either one alone. Broadleaf weed species were more susceptible to the application of the mixture than grass weed species. Galium spurium, Rumex japonicus, Aeschynomene indica, and Amaranthus retroflexus were the most susceptible among the broadleaf species and Setaria viridis was the most susceptible among the grass species. Broadleaf weed species demonstrated more growth suppression than grass weed species. For example, growth of G. spurium was reduced by 80.9% at 150 µg ml -1 of sorgoleone alone and by 33.7% at 7.5 mg ml -1 of hairy root extract alone; however their mixture reduced G. spurium growth by 100%. Moreover, the mixture reduced studied crop growth slightly more than sorgoleone or hairy root extract used individually. The ability of weed growth suppression using sorgoleone and hairy root extract of tartary buckwheat together offers interesting possibilities for effective weed management

Effect of nitrogen fertilizer and weed management on the yield of transplant aman rice

The research work was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during aman season from July to December 2015 to study the effect of nitrogen fertilizer and weed management on the growth and yield of transplant aman rice cv. BRRI dhan46. The experiment consisted of four fertilizer treatments viz. 0 kg N ha−1 (N0), 40 kg N ha−1(N1), 80 kg N ha−1(N2) and 120 kg N ha−1(N3) and four weeding treatments viz. one hand weeding at 20 DAT (W1), two hand weedings at 20 and 35 DAT (W2), three hand weedings at 20, 35 and 50 DAT (W3), weeding by Japanese rice weeder twice at 20 and 35 DAT (W4) and unweeded control (W5). The experiment was laid out in the randomized complete block design with three replications. The highest plant height (113.00 cm), number of total tillers hill−1 (8.74), number of effective tillers hill−1 (6.18), panicle length (21.98 cm), number of grains panicle−1 (114.20), grain yield (4.00 t ha−1), straw yield (5.25 t ha−1) and biological yield (9.25 t ha−1) were recorded in N2 (80 kg N ha−1) treatment. The lowest plant height (106.00 cm), number of total tillers hill-1 (7.20), number of effective tillers hill−1 (5.00), panicle length (20.70 cm), number of grains panicle−1 (97.60), grain yield (3.52 t ha−1), straw yield (4.46 t ha−1) and biological yield (7.97 t ha−1) were recorded from N0 (No nitrogen fertilizer control) treatment. On the other hand, the highest grain yield 4.23 t ha−1 was observed in three weedings condition because of the highest number of effective tillers hill−1 (6.81), number of grains panicle−1(111.10). The highest straw yield (5.51 t ha−1) was also found in three weeding condition. The lowest grain yield (3.40 t ha−1) was recorded in W5 (unweeded control) treatment. The lowest straw yield (4.31 t ha−1) was also observed in W5 (unweeded control) treatment because of the smallest plant (106.97 cm) and lower number of total tillers hill−1 (7.20). Therefore, 80 kg N ha−1along with three hand weedings at 20, 35 and 50 DAT may be used for obtaining the highest grain and straw yields of BRRI dhan4