Advanced Non-Chemical and Close to Plant Weed Control system for Organic Agriculture

Use of chemical has been reduced in agriculture for controlling weeds emergence. The use of alternative systems, such as cultural practices (mulching, flame, intercropping etc.) and mechanical system (hoe, tine etc.) has been introduced by various researchers. Automation technique based on sensors controlled system has enhanced the efficiency of the mechanical system for weed control. Mostly, low cost image acquisition sensors and optical sensor to detect the plant ensuring swift operation of vehicles close the crop plants to remove competitive weeds. The available system need to be evaluated to get best possible system for close to plant (CTP) weed removal. In the study various non-chemical weed control measures has been explored and 30 mechanical tools for CTP were evaluated. High precision tillage solutions and thermal weed control by pulsed lasers for eradication of stem or main shoot were found to be the most promising weed control concepts for CTP operation

Genetic variation for nutrient use efficiency in maize under different tillage and fertilization regimes with special emphasis to plant microbe interaction

Conservation tillage (no-till and reduced tillage) brings many benefits with respect to soil fertility and energy use, but it also has drawbacks regarding the need for synthetic fertilizers and herbicides. To promote conversation tillage in organic farming systems, crop rotation, fertilization and weed control have to be optimized. In addition, crop varieties are needed with improved nutrient use efficiency (NUE) and high weed competitiveness or tolerance

Pflanzenschonende mechanische Bearbeitung des Pflanzstreifens bei Kernobst und Alternativen: Optimierung der bestehenden Verfahren unter arbeitswirtschaftlichen Gesichtspunkten auf verschiedenen Standorten und Bodentypen

Weed control and cultivation is still a serious problem in organic pipfruit production. In a research project which has started in May 2004 cultivation and weed control equipment is tested in four different locations in Germany. The efficiency of the different machines in controlling the weed is as well acquired as possible effects on the fruit quality and the crop. After the first year with results statements to the efficiency can be made. The machines “Ladurner” and “Pellenc” are appropriate for cultivation and weed control in organic pipfruit production. No statements can be made about possible effects on the crop jet. These effects will become apparent not until three to four years of continuing the research projekt

Weed Search and Control: Theory and Application

The detectability of invasive organisms influences the costs and benefits of alternative control strategies, and the feasibility of eradicating an infestation. Search theory offers a mathematically rigorous framework for defining and measuring detectability, taking account of searcher ability, biological factors and the search environment. To demonstrate the application of search theory to invasive species control, invasive species detectability is incorporated into a population simulation model. The model is applied to a base set of parameter values that represent reasonable values for a hypothetical weed. The analysis shows the effects of detectability and search time on the duration of an eradication program. Furthermore, for a given level of detectability and search time, the analysis shows that the variables with the greatest influence on the duration of the eradication effort are search speed, kill efficiency and seed longevity. A series of Monte Carlo simulations are performed on a set of five scenarios, involving different combinations of plant longevity, seed longevity and plant fecundity. Results of these simulations are presented as probability distributions and allow us to calculate how the probability of eradication will be affected by search strategy.search and control, search theory, weed control, stage matrix, impedance factors, population dynamics, stochastic model, Farm Management,

Efficacy of new herbicide (bispyribac sodium 10% SC) against different weed flora, nutrient uptake in rice and their residual effects on succeeding crop of green gram under zero tillage

Field experiment was conducted in the wetland farms of Tamil Nadu Agricultural University, Coimbatore during rabi season (August to February) of 2011-12 to evaluate the herbicide (Bispyribac sodium 10% SC) on weed control and their nutrient management in direct seeded lowland rice. The experiment was laid out in a Randomized Block Design (RBD) with three replications. The results revealed that Early Post Emergence (EPOE) application of bispyribac sodium 10% SC 40 g ha-1 recorded higher weed control efficiency and lesser weed density, nutrient uptake at reproductive stage of the crop. Different weed management practices imposed on rice crop did not affect the germination of succeeding green gram

Control of macrophytes by grass carp (ctenopharyngodon idella) in a Waikato drain, New Zealand

Hornwort (Ceratophyllum demersum L.) and other aquatic macrophytes have historically been mechanically removed from the Rangiriri drain and Churchill East drain to maintain drain efficiency. As an alternative control method for the high plant biomass that accumulates at the end of summer, the effect of stocking diploid grass carp (Ctenopharyngodon idella L.) on the aquatic vegetation was evaluated in these Waikato drainage systems. At the start of the trial, both drains had a low diversity of aquatic macrophytes, and of the nine species (including the emergents), seven were exotic. Two months after grass carp were released to Churchill East drain (the treated drain) the four submerged and floating macrophyte species became scarce in the main drain. Over the same period, these species increased in biomass in Rangiriri drain (the untreated drain), where hornwort became dense and surface-reaching and remained so for the duration of the trial. However, grass carp did not control submerged vegetation in smaller side drains or the shallow, upper parts of the main drain, or the marginal sprawling species and emergent species. The cost of leasing the grass carp was similar to the cost of clearing the drains mechanically, but grass carp provided continuous weed control. However, subsequent to this trial, 62 dead grass carp were found in Churchill East drain in February 2001, and weed cover subsequently increased. This illustrates that grass carp management in New Zealand agricultural drains can be problematic due to periodic fish kills

Using minimum tillage to improve the efficiency of ecosystem service delivery on organic farms

Organic farming practices aim to maximise the delivery of ecosystem services in the agricultural landscape. However, in order to maintain optimal crop productivity the mouldboard plough is often used to control weeds and this can have negative effects on a range of soil parameters, thereby jeopardizing delivery of these services. Reduced tillage (RT) can be beneficial to soils and could improve both the efficiency of production and the delivery of ecosystem services on organic farms. However, abandoning the plough on organic farms is challenging due to impaired weed control. Here we report on a two year trial where an RT system with the Ecodyn, with duck feet shares operating at a depth of 7.6 cm in combination with seed drilling, was compared with mouldboard ploughing. Spring oat and spring barley establishment was improved under RT. Weed cover and biomass was greater under RT, but there was no difference in cereal grain yields in either year. The RT system used 71% less fuel and tillage operations took 72% less time that the plough system

Rigput brome (Bromus diandrus Roth.) management in a no tilled field in Spain

The adoption of no-till (NT) in the semi-arid region of Mediterranean Spain has promoted a weed vegetation change, where rigput brome (Bromus diandrus Roth) represents a main concern. In order to avoid complete reliance on herbicides, the combination of several control methods, without excluding chemical ones, can contribute to an integrated weed management (IWM) system for this species. In this field study, 12 three-year management programs were chosen, in which alternative non-chemical methods¿delay of sowing, crop rotation, sowing density and pattern, stubble removal¿are combined with chemical methods to manage B. diandrus in winter cereals under NT. Moreover, their effects on weed control and crop productivity were analyzed from the point of view of the efficiency of the control methods, based on a previously developed emergence model for B. diandrus. All management programs were effective in reducing the weed infestation, despite the different initial weed density between blocks. For high weed density levels (60-500 plants m2), two years of specific managements resulted in 99% reduction of its population. For even higher density levels, three years were needed to assure this reduction level. Both the emergence of the weed and the crop yields are mainly driven by the seasonal climatic conditions in this semi-arid area. For this reason, among the non-chemical methods, only crop rotation and sowing delay contributed to an effective weed population decrease as well as an increase in the economic income of the yield. The other alternative methods did not significantly contribute to controlling the weed. This work demonstrates that mid-term management programs combining chemical with non-chemical methods can effectively keep B. diandrus under control with economic gains compared to traditional field management methods in semi-arid regions.This research was funded by Bayer CropScience, grant number C14045, and the Economy Ministry of Spain, grant number AGL2014-52465-C4-2-R

Bio-efficacy of tank mixed herbicides for control of complex weed flora in soybean (Glycine max L. Merril)

A field experiment was conducted at ZARS, Jhabua (M.P.) during kharif 2014 to find out most suitable and efficient method of weed control in soybean. The experiment consisted of nine treatments laid out in randomized block design with three replications. All the weed management practices led to significant reduction in density and dry matter of weeds as compared to weedy check. Two hand weeding (20 & 40 DAS) recorded lowest weed density (4.9/ m2), weed dry matter (22.35 g/m2) with highest weed control efficiency of 59.67% and found at par with the application of Chlorimuron Ethyl @ 9gm /ha + Quizalofop-p-ethyl @ 50 g /ha (density 5.48/ m2, dry matter 26.62 g/m2 and WCE of 51.97%) and Imazethapyr @ 35 g /ha + Imazamox @ 35 g/ha (density 6.13/ m2, dry matter 26.00 g/m2 and WCE of 53.08%). Maximum yield of 1782 kg/ha was recorded in two hand weeding (20 & 40 DAS) closely followed by Chlorimuron Ethyl @ 9gm /ha + Quizalofop-p-ethyl @ 50 g /ha (1723 kg/ha) and Imazethapyr @ 35 g / ha + Imazamox @ 35 g/ha (1697 kg/ha). Reduction in soybean yield in weedy check to be recorded is 38.78 per cent when compared to weed free and 36.68 per cent in comparison to Chlorimuron Ethyl @ 9gm /ha + Quizalofopp-ethyl @ 50 g /ha. However, highest Benefit to Cost ratio is recorded in Chlorimuron Ethyl +Quizalofop-p-ethyl (3.26) closely followed by Imazethapyr + Imazamox (3.22) and Weed free (3.21)

Organic Farming Scenarios: Operational Analysis and Costs of implementing Innovative Technologies

The objective of this study has been to design a number of farm scenarios representing future plausible and internally consistent organic farming enterprises based on milk, pig, and plant production and use these farm scenarios as the basis for the generation of generalised knowledge on labour and machinery input and costs. Also, an impact analysis and feasibility study of introducing innovative technologies into the organic production system has been invoked. The labour demand for the production farms ranged from 61 to 253hha1 and from 194 to 396hLU1 (LU is livestock units) for work in the animal houses. Model validation results showed that farm managerial tasks amount to 14–19% of the total labour requirement. The impact of introducing new technologies and work methods related to organic farming was evaluated using two innovative examples of weed control: a weeding robot and an integrated system for band steaming. While these technologies increased the capital investment required, the labour demand was reduced by 83–85% in sugar beet and 60% in carrots, which would improve profitability by 72–85% if fully utilised. Profitability is reduced, if automation efforts result in insufficient weed removal compared to manual weeding. Specifically, the benefit gained by robotic weeding was sensitive to the weed intensity and the initial price of the equipment, but a weeding efficiency of under 25% is required to make it unprofitable. This approach demonstrates the feasibility of applying and testing operational models in organic farming systems in the continued evaluation and documentation of labour and machinery inputs