Oilseed Rape Yield Performance in the Clearfield® System under Varying Management Intensities

Oilseed rape production is under pressure due to a limited availability of herbicides. Therefore, the performance in terms of management intensity (MI) and herbicide strategy (HS) and the involved yield formation was evaluated in a two-year Clearfield® oilseed rape field experiment. Furthermore, weed density and weed composition were also investigated. The variants of MI were standard sowing density (StS; seed rate: 50 seeds m−2, primary tillage: plow, row width: 12 cm), reduced sowing density (RD; seed rate: 25 seeds m−2, primary tillage: plow, row width: 50 cm), and strip-till (ST; seed rate: 25 seeds m−2, primary tillage: strip tillage, row width: 50 cm). The variants of HS were preemergence strategy (PES; application of dimethachlor, napropamide, clomazone in preemergence and application of prapaquizafop in postemergence) and Clearfield® strategy (CLS; application of imazamox, quinmerac in preemergence, no postemergence herbicide application). In the first year of the trial, there were no interactions between the factors in terms of grain yield. Grain yield in StS was 3.85 t and 5.2% significantly lower than in ST, and the value of RD was not significantly different from StS and ST. Grain yield in CLS was 3.7 t and 2.7% lower than in PES. In the second year of the trial, the grain yield in ST CLS was significantly lower, and there were no significant differences between the other variants. Higher weed emergence was observed in CLS RD (2.7 to 4 times higher weed density compared to PES RD) and CLS ST (2.8 to 4.5 times higher weed density compared to PES ST). No significant differences existed between StS PES and StS CLS in both trial years. The Clearfield® system offers significant advantages in the control of cruciferous weeds. Although these did not occur on the trial fields, the Clearfield® system in this study showed to be an alternative to the more common pre-emergence system, especially with regard to the parameter grain yield.

Technology and tools for strip tillage in the energy-saving system of agriculture in Volgograd region

The article highlights the results of research in strip farming. The method of minimum soil tillage, a resource-saving working body ROPA and a soil tillage tool for strip ripping OMPO-5.6, which are designed to perform fine soil tillage with strip deepening, are proposed. Adjustment of loosening depth from bit is achieved within the range of 0.25-0.4 m and is selected taking into account the crop grown in the farm. Availability of undercutter tine allows to regulate parameters of continuous ripping zone. Parameters of treated and untreated strips are regulated by location of undercutter paw. The design of the tool provides a smooth adjustment mechanism by which the width of the cultivated strip can be changed within 0.25-0.35 m. This makes it possible to use the implement for different tilled crops. The technological process carried out by this working body helps to reduce the wounding effect on the soil through a simple technical solution. Installation of side undercutting discs allows cultivating the soil within a given strip, and the process of cutting the soil in a blocked environment improves the quality of treatment.

Applicability of plastic mulch and conservation strip tillage for potato production in Bangladesh

<p>Application of plastic mulches in potato production is rarely used by farmers in Bangladesh although it has a good prospect for saving irrigation water, weed control, maintaining tuber quality, and increasing yield. A study was conducted in experimental farm at Rural Development Academy (RDA), Bogura, Bangladesh to evaluate the precision of irrigation water for potato production using different colored plastic mulches i.e, black and blue in combination with conservation strip tillage and control (no-mulch). Four different treatments were prepared where some of the phenological characteristics of plants as well as yield of potato were compared among treatments by applying the same amount of irrigation water. The results showed that treatment with black plastic mulch had the highest tuber growth as well as yield of 25.1 t ha^-1 compared to other treatments while other treatments such as blue plastic mulch, control, and strip tillage had a yield of 16.37, 13.75, and 15.75 t ha^-1, respectively. Potato plants having black plastic mulch took less time to mature in comparison to other treatments. Black plastic mulch restricts soil moisture evaporation and keeps the soil warm. In conclusion, potato production with various mulches has a great scope in a semi-arid region like Bangladesh and present experimental results will help to improve the understanding of potato growers for adopting best mulch management practices.</p>

Conservation Strip Tillage Leads to Persistent Alterations in the Rhizosphere Microbiota of Brassica napus Crops

Microbes play vital roles in many soil ecosystem functions and services, which are crucial for agricultural productivity. Among different agricultural management practices, soil tillage methods can result in changes in a soil's physical, chemical and biological properties, including the soil microbiome. In addition, crop type and the plant developmental stage are important drivers of rhizosphere bacterial microbiota structure and composition. Here, we have used high-throughput, 16S amplicon sequencing to explore the rhizosphere bacterial structure and composition of Brassica napus (winter oilseed rape) in two contrasting tillage practices; conventional-plough based tillage and conservation strip tillage, over three different plant growth stages (vegetative, flowering and harvesting stage). This was the first year that conservation strip tillage was used in this field, as in previous years plough based tillage practices has been used. Our findings show that tillage and growth stages were important determinants of microbial community structure and composition, but the effect of tillage became stronger at plant maturity. The combined effect of conservation strip tillage and harvesting stage had a impact on the rhizosphere microbiota selection. The rhizosphere bacterial community of winter oilseed rape under conservation strip tillage was different to that under conventional tillage. Our data suggests that different tillage regimes created distinct ecological niches that selected different microbiota with potential consequences for the ecosystem services provided to the plants and the soil environment.

Soil Nitrate Nitrogen Content and Grain Yields of Organically Grown Cereals as Affected by a Strip Tillage and Forage Legume Intercropping

Reducing tillage intensity and increasing crop diversity by including perennial legumes is an agrotechnical practice that strongly affects the soil environment. Strip tillage may be beneficial in the forage legume–cereals intercropping system due to more efficient utilization of biological nitrogen. Field experiments were conducted on a clay loam Cambisol to determine the effect of forage legume–winter wheat strip tillage intercropping on soil nitrate nitrogen (N-NO3) content and cereal productivity in various sequences of rotation in organic production systems. Forage legumes (Medicago lupulina L., Trifolium repens L., T. alexandrinum L.) grown in pure and forage legume–winter wheat (Triticum aestivum L.) strip tillage intercrops were studied. Conventional deep inversion tillage was compared to strip tillage. Nitrogen supply to winter wheat was assessed by the change in soil nitrate nitrogen content (N-NO3) and total N accumulation in yield (grain and straw). Conventional tillage was found to significantly increase N-NO3 content while cultivating winter wheat after forage legumes in late autumn (0–30 cm layer), after growth resumption in spring (30–60 cm), and in autumn after harvesting (30–60 cm). Soil N-NO3 content did not differ significantly between winter wheat strip sown in perennial legumes or oat stubble. Winter wheat grain yields increased with increasing N-NO3 content in soil. The grain yield was not significantly different when comparing winter wheat–forage legume strip intercropping (without mulching) to strip sowing in oat stubble. In forage legume–winter wheat strip intercropping, N release from legumes was weak and did not meet wheat nitrogen requirements.

Optimizing the Seed Rate for Maximized Yield And Benefits of Wheat Under Strip Tillage In Bangladesh

An on-farm experiment was conducted at the farmer's field located at the Durbachara village of Gauriopur upazilla under the Mymensingh district of Bangladesh from November 2015 to March 2016 to study the effect of seed rate on yield performance of wheat under strip tillage. Wheat cv. BARI Gom-26 was sown under conventional tillage (CT) vs. strip tillage (ST), including four seeding rates viz. 100, 110, 120, and 130 kg ha-1. The CT was done with a two-wheel tractor and consisted of two primary tillages followed by two secondary tillages. The ST was done using a Versatile Multi-crop Planter (VMP) machine in a single pass process. A pre-plant herbicide, glyphosate was applied 3 days before of ST operation @ 3.7 L ha-1. The experiment was laid out in a randomized complete block design with four replications. The impact of tillage methods on the seed rate was found significant in the yield and economic profit of wheat. The longest spike with the highest number of grains spike-1, the highest weight of 1000-grain, grain yield, and BCR was recorded when 120 kg seeds of wheat sown with strip tillage. This practice produced a 25% higher yield and earned 51% higher profit than the practice of seeding 100 kg seeds ha-1 with conventional tillage. SAARC J. Agric., 19(1): 45-56 (2021)

Strip Tillage and Crop Residue Retention Decrease the Size but Increase the Diversity of the Weed Seed Bank under Intensive Rice-Based Crop Rotations in Bangladesh

Cropping under conservation agriculture (CA) has become increasingly attractive among farmers in recent years. However, weed control may be more difficult during the transition to CA from conventional establishment methods due to the reduction in tillage intensity. Conversely, CA changes to weed dynamics can alter the weed seed bank in the longer run. In Bangladesh’s intensively cropped rice-based rotations, the nature of weed seed bank shifts over time after adopting CA are poorly known. Two 2-year studies were sampled from on-farm CA experiments under wheat-mungbean-winter rice and monsoon rice-mustard-winter rice rotations. We investigated the effects of reduced soil disruption in the form of strip-tillage (ST) combined with increased deposition of standing reside from previous crops (0 vs. 50%). The weed seed bank in 0–5, 5–10, and 10–15 cm depths of soil were quantified in a shade-house experiment by measuring weed emergence over 12 months in seedling trays. After 2 years of field study, the year-round count of emerged weeds from the seed bank showed that ST plus 50% mulch had a lower weed abundance and biomass and fewer weed species than that of conventional tillage (CT) without residue. The perennial weeds Ageratum conyzoides L., Alternanthera philoxeroides L., Cynodon dactylon L., Cyperus rotundus L., Jussia decurrence Walt., Leersia hexandra L., Scirpus mucronatus (L.) Palla., and Solanum torvum Sw. were enriched in the smaller-sized ST seed banks in terms of both density and biomass. The CT, on the other hand, was dominated by annual weeds: Cyperus difformis L., Cyanotis axillaris Roem., Echinochloa crus-galli (L.) Beauv., Eleusine indica L., Fimbristylis miliacea (L.) Vahl., and Rotala ramosior L. Overall, ST plus 50% residue had a more diverse seed bank than CT without mulch. The majority of weed seeds were amassed in the 0–5 cm soil depth of the ST, while most of them were accumulated in the 10–15 cm layer of the CT. The wheat-mungbean-winter rice rotation had a more diverse floristic composition with many more weed species than the monsoon rice-mustard-winter rice rotation.

Comparitive Field Evaluation of Roto Drill Cum Herbicide Applicator

Individual field operations such as ploughing, clod breaking, stubble clearance and leveling are necessary for the preparation of even and fine seed bed. These operations consume time and labor which become more economical. Strip tillage, direct paddy sowing, Zero tillage, requires minimum soil manipulation and no tillage respectively, where there incur reduced cost of operation. Timely sowing and proper weed control results in bringing out good returns. Farmers have many options for choosing equipment that is required to grow and harvest a crop. Farmers may own their own equipment, lease it, or have the field operations completed using custom operators. Considering the above facts and importance of paddy, in-order to reduce cost of cultivation a multi crop roto drill cum herbicide applicator was developed by combining three varied machines such as rotovator, seed drill and herbicide applicant or equipment at College of Agricultural Engineering, Bapatla. A tractor drawn roto drill cum herbicide sprayer was developed, evaluated and compared its cost economics with individual operations. Roto drill is the combination of rotavator, seed hopper and rocker sprayer pump. It pulverizes the soil, drills the seed and applies herbicide in single pass of tractor. The cost activity of multi crop roto drill cum herbicide applicator for performing three tasks was estimated as Rs/h. 641.00. While the individual costs of operation for tillage, sowing and herbicide application were computed as Rs/h. 571.00, 540.00 and 95.00 respectively. The cost of operation per one hour for developed multi crop roto drill cum herbicide applicator was 46.72% less when compared with costs of individual tasks.