scholarly journals Impact of a Cultivation System upon the Weed Seedbank Size and Composition in a Mediterranean Environment

Agriculture ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 192 ◽  
Author(s):  
Alessia Restuccia ◽  
Sara Lombardo ◽  
Giovanni Mauromicale

The knowledge of the soil seedbank is crucial to predict the dynamics of weed communities and potential future problems in agroecosystem weed management. Therefore, the aim of this study was to evaluate the qualitative and quantitative variation of the potential and real weed flora as a function of different cultivation systems (namely organic, conventional and uncultivated) in a Mediterranean environment (Sicily, south Italy). The results proved that soil seedbank density was significantly different in superficial (0–10 cm) and deeper soil layers (10–15 cm) in both organic and conventional cultivation systems. Portulacaceae and Amaranthaceae were the dominant botanical families, although they achieved a higher total number of seeds m−2 under a conventional cultivation system than under organic and uncultivated ones. The whole weed flora was represented by 45 taxa, but the presence of the crop reduced the qualitative and quantitative composition of real weed flora. In conclusion, the knowledge of the seedbank size and composition, as well as the variation in time and space of real flora, may contribute to predict the dynamics of weed emergence and their possible interference with crops. In particular, information on the weed dynamics is essential to develop sustainable control protocols, especially under organic farming.

2019 ◽  
Vol 51 (1) ◽  
pp. 54
Author(s):  
Pijush Kanti Mukherjee ◽  
Putan Singh ◽  
Shobha Sondhia ◽  
R.L. Sagar

2021 ◽  
Vol 3 ◽  
Author(s):  
Katie M. Patterson ◽  
Lauren M. Schwartz-Lazaro ◽  
Gabrielle LaBiche ◽  
Daniel O. Stephenson

The soil seedbank allows for long-term persistence of weed species in agricultural fields. Some weed species can persist in the soil seedbank for extended periods. Restricting inputs into the weed seedbank has a large impact on future population density and influences management practices of these weeds in soybean production systems. Harvest weed seed control (HWSC) tactics incorporate mechanical and cultural management strategies to target weed seeds present at harvest. A 3-year trial was initiated to determine if continual use of the HWSC method, narrow windrow burning, selects for earlier seed set and shattering in Louisiana soybean. No shifts in weed populations or shattering time were observed. However, there was a significant reduction in weed density and the weed seed present in the soil seedbank when HWSC and robust herbicide programs were used in combination. Therefore, utilizing multiple effective weed management strategies is imperative in reducing the soil seedbank.


2019 ◽  
Vol 6 (02) ◽  
Author(s):  
MOHAN SINGH ◽  
OMBIR SINGH ◽  
ROHITASAV SINGH

A field experiment was conducted at the Crop Research Centre of Govind Ballabh Pant University of Agriculture and Technology Pantnagar, Udham Singh Nagar during continuous two years to study the weed flora, yield and nutrient uptake of wheat (Triticum aestivum L.) under different wheat establishment methods in main plots and seven weed management in sub plots. Phalaris minor was the most dominant weed at 60 DAS contributed 55.0 per cent of total weed population. Melilotusindica was the major non grassy weeds in wheat which contributed 11 per cent to total weed population during respective years. Sowing of wheat with zero tillage significantly reduced the Phalaris minor density as compared to conventionally tilled wheat after transplanted rice, 60 per cent Phalaris minor emerged from 0-3 cm in reduced and conventional tillage where as in zero tillage after transplanted rice there was 55 per cent emergence from 0-3 cm layer.The highest grain yield was obtained in two hand weedings done at 30 and 60 DAS and was at par with Isoproturon 1.0 kg ha-1 + Metsulfuron methyl 4 g ha-1 at 30 DAS and Clodinafop – Propargyl 60 g ha-1 at 30 DAS fb. Metsulfuron methyl 4 g ha-1 at 37 DAS. Zero tillage resulted in significantly higher uptake of NPK by wheat plants as compared to conventional tillage, whereas reduced tillage recorded minimum NPK, which was significantly lower over the other treatments of wheat establishment methods.


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1565
Author(s):  
María Belén D’Amico ◽  
Guillermo R. Chantre ◽  
Guillermo L. Calandrini ◽  
José L. González-Andújar

Population models are particularly helpful for understanding long-term changes in the weed dynamics associated with integrated weed management (IWM) strategies. IWM practices for controlling L. rigidum are of high importance, mainly due to its widespread resistance that precludes chemical control as a single management method. The objective of this contribution is to simulate different IWM scenarios with special emphasis on the impact of different levels of barley sowing densities on L. rigidum control. To this effect, a weed–crop population model for both L. rigidum and barley life cycles was developed. Our results point out: (i) the necessity of achieving high control efficiencies (>99%), (ii) that the increase of twice the standard sowing density of barley resulted in a reduction of 23.7% of the weed density, (iii) non-herbicide-based individual methods, such as delayed sowing and weed seed removal at harvest, proved to be inefficient for reducing drastically weed population, (iv) the implementation of at least three control tactics (seed removal, delay sowing and herbicides) is required for weed infestation eradication independently of the sowing rate, and (v) the effect of an increase in the sowing density is diluted as a more demanding weed control is reached. Future research should aim to disentangle the effect of different weed resistance levels on L. rigidum population dynamics and the required efficiencies for more sustainable IWM programs.


2008 ◽  
Vol 73 (5) ◽  
pp. 531-540 ◽  
Author(s):  
Ljiljana Stanojevic ◽  
Mihajlo Stankovic ◽  
Vesna Nikolic ◽  
Ljubisa Nikolic

The anti-oxidative and antimicrobial activities of different extracts from Hieracium pilosella L. (Asteraceae) whole plant were investigated. The total dry extracts were determined for all the investigated solvents: methanol, dichloromethane, ethyl acetate and dichloromethane: methanol (9:1). It was found that the highest yield was obtained by extraction with methanol (12.9 g/100 g of dry plant material). Qualitative and quantitative analysis were performed by the HPLC method, using external standards. Chlorogenic acid, apigenin-7-O-glucoside and umbelliferone were detected in the highest quantity in the extracts. The qualitative and quantitative composition of the extracts depends on the solvent used. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect of the extracts was determined spectrophotometrically. The highest radical scavenging effect was observed in the methanolic extract, both with and without incubation, EC50 = 0.012 and EC50 = 0.015 mg ml-1, respectively. The antimicrobial activities of the extracts towards the bacteria (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Salmonella enteritidis and Klebsiella pneumoniae) and the fungi (Aspergillus niger and Candida albicans) were determined by the disc diffusion method. The minimal inhibitory concentrations were determined for all the investigated extracts against all the mentioned microorganisms.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Hidayat Hussain ◽  
Ahmed Al-Harrasi ◽  
Ahmed Al-Rawahi ◽  
Javid Hussain

The properties ofBoswelliaplants have been exploited for millennia in the traditional medicines of Africa, China, and especially in the Indian Ayurveda. In Western countries, the advent of synthetic drugs has obscured the pharmaceutical use ofBoswellia, until it was reported that an ethanolic extract exerts anti-inflammatory and antiarthritic effects. Frankincense was commonly used for medicinal purposes. This paper aims to provide an overview of current knowledge of the volatile constituents of frankincense, with explicit consideration concerning the diverseBoswelliaspecies. Altogether, more than 340 volatiles inBoswelliahave been reported in the literature. In particular, a broad diversity has been found in the qualitative and quantitative composition of the volatiles with respect to different varieties ofBoswellia. A detailed discussion of the various biological activities ofBoswelliafrankincense is also presented.


2012 ◽  
Vol 151 (2) ◽  
pp. 229-245 ◽  
Author(s):  
N. COLBACH ◽  
D. MÉZIÈRE

SUMMARYEnvironmental problems mean that herbicide applications must be drastically reduced and optimized. Models that quantify the effects of crop management techniques on weed dynamics are valuable tools for designing weed management strategies. Indeed, the techniques to be optimized are numerous and diverse, and their effects vary considerably with environmental conditions and the state of the weed flora. In the present study, a mechanistic weed dynamics model,AlomySys, was used to carry outin silicoexperiments in order to: (1) rank crop management components according to the resulting decrease in weed infestation, and (2) study the sensitivity of the major component effects to biophysical field state variables in order to identify indicators and thresholds that could serve for future decision-rules for farmers. The various results were compiled into rules for optimizing timing and other options (tillage tools, herbicide types) for the different crop management techniques. The rules were based on a series of biophysical field state variables, i.e. cumulated rainfall, thermal time, soil moisture and weed densities prior to the operation, in the previous and pre-previous crops. For instance, the first tillage should be delayed until the cumulated rainfall since harvest exceeds 50 mm and be carried out in moist conditions. Mouldboard ploughing is advised if the infestation of the previous crop exceeds 20 weeds/m2and particularly if this exceeds 0·3 times that of the pre-previous crop. Ploughing should occur when the cumulated rainfall since harvest reaches 100–200 mm. The effects of crop succession and long-term effects of management techniques have been studied in a companion paper (Colbachet al. 2012).


2021 ◽  
pp. 92-95
Author(s):  
Александр Николаевич Остриков ◽  
Наталья Леонидовна Клейменова ◽  
Инэсса Николаевна Болгова ◽  
Максим Васильевич Копылов ◽  
Екатерина Юрьевна Желтоухова

Использование растительных масел в рационе человека необходимо для удовлетворения энергетической потребности организма и регулирования биологических процессов. В настоящей работе представлен качественный и количественный состав витаминов и токоферолов различных видов растительных масел, полученных холодным отжимом из выращенных в нашей стране расторопши, горчицы, подсолнечника, рыжика, рапса. Проведен сравнительный анализ литературных источников о наличии витаминов и токоферолов в различных растительных маслах. Количественный и качественный витаминный состав для одного и того же вида масла, по данным разных авторов, варьируется в достаточно широком диапазоне. В ходе исследования изучен витаминный состав пяти растительных масел. Результаты свидетельствуют, что наибольшей витаминной активностью обладают масла рыжиковое, расторопши и горчичное. Установлено наличие витамина А в маслах: рыжиковом (27,15±0,002 мкг%), расторопши (19,07±0,02 мкг%), горчичном (24,77±0,02 мкг%). Витамины В и В присутствуют в маслах горчичном, рыжиковом и расторопши; витамин В определен в горчичном и рыжиковом, В - в рыжиковом и расторопши. В маслах горчичном и расторопши присутствует витамин В. Наиболее богаты витамином Е масла рыжиковое (52,8±0,02 мг%), подсолнечное (48,3±0,02 мг%), расторопши (47,12±0,02 мг%). Витамин К и токоферолы определены во всех растительных маслах. Присутствие b-каротина обнаружено в рыжиковом (1,237±0,004 мг%), расторопши (0,812±0,002 мг%), подсолнечном (0,22±0,02 мг%) и горчичном (0,148±0,002 мг%) маслах. Анализируемые масла холодного отжима можно рассматривать как ценный источник при проектировании новых многоцелевых продуктов или побочных продуктов для промышленного, косметического и фармацевтического использования. The use of vegetable oils in the human diet is necessary to meet the energy needs of the body and regulate biological processes. This work presents the qualitative and quantitative composition of vitamins and tocopherols of various types of vegetable oils obtained by cold pressing from silybum marianum, mustard, sunflower, camelina, rapeseed grown in our country. A comparative analysis of the literature on the presence of vitamins and tocopherols in various vegetable oils has been carried out. The quantitative and qualitative vitamin composition for the same type of oil, according to different authors, varies in a wide range. During the study, the vitamin composition of five vegetable oils was studied. The results indicate that the following oils have the highest vitamin activity: camelina, silybum marianum and mustard. The presence of vitamin A was found in oils: camelina (27.15±0.002 μg%), silybum marianum (19.07±0.02 μg%), mustard (24.77±0.02 μg%). Vitamins B and B are present in mustard, camelina and silybum marianum oils; vitamin B is found in mustard and camelina; B in camelina and silybum marianum. Mustard and silybum marianum oils contain vitamin B. The richest in vitamin E are camelina (52.8±0.02 mg%), sunflower (48.3±0.02 mg%), silybum marianum (47.12±0.02 mg%). Vitamin K and tocopherols are found in all vegetable oils. The presence of b-carotene was found in camelina (1.237±0.004 mg%), silybum marianum (0.812±0.002 mg%), sunflower (0.22±0.02 mg%) and mustard (0.148±0.002 mg%) oils. The analyzed cold-pressed oils can be considered as a valuable resource when designing new multipurpose products or by-products for industrial, cosmetic and pharmaceutical applications.


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