scholarly journals Chemical control of different Digitaria insularis populations and management of a glyphosate-resistant population

2015 ◽  
Vol 33 (1) ◽  
pp. 93-101 ◽  
Author(s):  
N.M. CORREIA ◽  
L.T. ACRA ◽  
G. BALIEIRO
Keyword(s):  
Chemical Control ◽  
Standard Treatment ◽  
The Other ◽  
Effective Strategy ◽  
Grain Production ◽  
Resistant Population ◽  
Different Populations ◽  
Glyphosate Herbicide ◽  
Combination Of Methods ◽  
Adult Plants

This study aimed to control different populations of Digitaria insularisby glyphosate herbicide, isolated and mixed, besides the combination of methods (chemical and mechanical) to manage resistant adult plants. Three experiments were conducted, one in pots which were maintained under non-controlled conditions and two under field conditions. In the experiment in pots, twelve populations of D. insularis were sprayed with isolated glyphosate (1.44 and 2.16 kg a.e. ha-1) and mixed (1.44 and 2.16 kg a.e. ha-1) with quizalofop-p tefuryl (0.12 kg i.a. ha-1). The treatment of 1.44 kg a.e. ha-1 of glyphosate plus 0.12 kg a.i. ha-1 of quizalofop was sufficient for adequate control (>95%) of all populations. Population 11 (area of grain production in Itumbiara, GO) was considered sensitive to glyphosate. Others populations were moderately sensitive or tolerant to the herbicide. In the field, the plants of D. insularis of one of the experiments were mowed and, in the other, there were not. Eight treatments with herbicides [isolated glyphosate (1.44 and 2.16 kg a.e. ha-1) and mixed (1.44 and 2.16 kg a.e. ha-1) with quizalofop-p-tefuryl at 0.12 kg a.i. ha-1), clethodim at 0.108 kg a.i. ha-1) or nicosulfuron at 0.06 kg a.i. ha-1)] were assessed, in combination with or without sequential application of the standard treatment, sprayed 15 days after the first application. The combination of the mechanic control with the application of glyphosate (2.16 and 1.44 kg a.e. ha-1) plus quizalofop-p-tefuryl (0.12 kg a.i. ha-1) or clethodim (0.108 kg a.i. ha-1), associated to the sequential application, was the most effective strategy for the management of adult plants of resistant D. insularis.

An assessment of the factors controlling the productivity of maize in England

1951 ◽  
Vol 41 (3) ◽  
pp. 271-281 ◽  
Author(s):  
E. S. Bunting ◽  
G. E. Blackman
Keyword(s):  
Dry Matter ◽  
Field Experiments ◽  
Plant Density ◽  
Spatial Arrangement ◽  
The Other ◽  
Mass Selection ◽  
Grain Production ◽  
Forage Production ◽  
Field Scale ◽  
Other Hand

Between 1942 and 1950, some thirty field experiments have been carried out in the southern half of England to assess the potential value, either for grain or forage production, of seventeen openpollinated flint or dent maizes together with twentynine single or double hybrids of American or Canadian origin.Early-maturing flint varieties will consistently ripen grain, but before mechanical threshing or storage, the cobs require drying. Sibthorp, a mass selection made from an unknown German variety, is the earliest and most productive flint maize so far tested, and in the experiments has yielded as much as 39 cwt. of grain per acre with an average of 24 cwt. The earliest American hybrids, i.e. those with a U.S.A. rating of 80 days from sowing to maturity, give very high yields of grain in favourable seasons. Within the group Wisconsin 240–275, a yield level equal to or exceeding 50 cwt./acre has on occasion been recorded. On the other hand, in the most unfavourable years, such hybrids just failed to produce ripe cobs.Attempts to maintain sixty-five parent inlines of the earliest hybrids have largely failed. However, many of the parent single crosses have matured, and the production on a field scale of the double-cross seed of both Wisconsin 240 and 255 has been carried out.Spacing experiments indicate that for optimum grain production a density of 6 plants/sq.yd. is required for both flint varieties and the earliest hybrids. A spatial arrangement of individual plants is to be preferred to that of groups or hills.American hybrids, in the class of ‘90 days’ to maturity, will in all but the most unfavourable seasons reach the ‘early-dent’ stage of the grain before the incidence of autumn frosts. Yields of dry matter of plants harvested in this phase have ranged from 30 to 85 cwt. of dry matter per acre. In these trials, the plant density was standardized at 4 plants/sq.yd. and higher densities may be demanded for optimal yields.The ratio of the ‘ear’ (that is, the cob, immature grain and enclosing leaf sheaths) to the total shoot weight at harvest varies greatly with the variety or hybrid. With White Horsetooth, the usual variety grown for fodder in England, no cobs are formed before the plants are killed by frost, while with the early hybrids, the ear may be half the weight of the whole shoot.The earliest variety Sibthorp from an early May sowing takes approximately 70–80 days to reach full anthesis, while ‘80-day’ American hybrids are a week later. From sowing to full maturity the period in England is from 140 to 160 days, thus compared to conditions in Minnesota the period is nearly twice as long. Because of the much slower rate of development and because of the humidity of English autumns, it is concluded that until the date of maturity can be advanced some 14 days, grain production on a field scale is not yet feasible. On the other hand, many of the American hybrids are well fitted to the production of silage. The greatest drawback to the introduction of such hybrids is the liability of the seed and seedlings to be attacked by rooks.

scholarly journals JKRW Link Prediction – A New Ensemble Technique Based on Merging Other Known Techniques in The Social Network Analysis

2021 ◽  
Vol 15 (12) ◽  
pp. 125
Author(s):  
Aya Taleb ◽  
Rizik M. H. Al-Sayyed ◽  
Hamed S. Al-Bdour
Keyword(s):  
Link Prediction ◽  
Preferential Attachment ◽  
Large Data ◽  
The Other ◽  
Jaccard Coefficient ◽  
Ensemble Technique ◽  
Signed Rank ◽  
Proposed Model ◽  
Different Populations ◽  
A New Technique

In this research, a new technique to improve the accuracy of the link prediction for most of the networks is proposed; it is based on the prediction ensemble approach using the voting merging technique. The new proposed ensemble called Jaccard, Katz, and Random models Wrapper (JKRW), it scales up the prediction accuracy and provides better predictions for different sizes of populations including small, medium, and large data. The proposed model has been tested and evaluated based on the area under curve (AUC) and accuracy (ACC) measures. These measures applied to the other models used in this study that has been built based on the Jaccard Coefficient, Katz, Adamic/Adar, and Preferential attachment. Results from applying the evaluation matrices verify the improvement of JKRW effectiveness and stability in comparison to the other tested models.  The results from applying the Wilcoxon signed-rank method (one of the non-parametric paired tests) indicate that JKRW has significant differences compared to the other models in the different populations at <strong>0.95</strong> confident interval.

scholarly journals BIOLOGICAL CONTROL IN LEAF-CUTTING ANTS, Atta sexdens (HYMENOPTERA: FORMICIDAE), USING PATHOGENIC FUNGI

2021 ◽  
Vol 45 ◽  
Author(s):  
Tarcísio Marcos Macedo Mota Filho ◽  
Luis Eduardo Pontes Stefanelli ◽  
Roberto da Silva Camargo ◽  
Carlos Alberto Oliveira de Matos ◽  
Luiz Carlos Forti
Keyword(s):  
Biological Control ◽  
Chemical Control ◽  
Pathogenic Fungi ◽  
Behavioral Changes ◽  
The Other ◽  
Fungus Garden ◽  
Atta Sexdens ◽  
Main Method ◽  
New Methods ◽  
Leaf Cutting

ABSTRACT Chemical control using toxic baits containing the active ingredient sulfluramid at 0.3% (w/w) is the main method for controlling leaf-cutting ants of the genera Atta and Acromyrmex. However, since 2009, when sulfluramid was included in Annex B of the Stockholm Convention on Persistent Organic Pollutants, there has been an intense search for new methods that are efficient in controlling these insects. Among said new methods, biological control using pathogenic fungi has shown promising results in laboratory conditions. The objective of this study, given the context presented, was to assess the potential of the fungi Beauveria bassiana and Trichoderma harzianum in controlling Atta sexdens. Colonies of A. sexdens were exposed to the fungi by means of formulated baits provided in a foraging chamber, or of suspensions sprayed on the fungus garden, and had their behavioral changes recorded for 21 days. For both formulations, concentrations of 10 and 20% (w/w) of the fungi being studied were used. The results allowed concluding that baits containing 10 and 20% (w/w) of the fungi B. bassiana and T. harzianum were not efficient in controlling colonies of A sexdens. On the other hand, spraying suspensions of 20% (w/w) of B. bassiana and 10% and 20% (w/w) of T. harzianum was efficient and resulted in 100% mortality of the colonies 11, 9 and 7 days after application, respectively. These findings indicate that the fungi B. bassiana and T. harzianum are promising as agents for the control of A. sexdens colonies, when sprayed on the fungus garden, although there are still some challenges as to their use related to the development of technologies for the application of the pathogen.

scholarly journals Interaction of Arsenophonus with Wolbachia in Nilaparvata lugens

2019 ◽  
Author(s):  
Huifang Guo ◽  
Na Wang ◽  
Hongtao Niu ◽  
Dongxiao Zhao ◽  
Zhichun Zhang
Keyword(s):  
Nilaparvata Lugens ◽  
The Other ◽  
Single Infection ◽  
Double Infection ◽  
Infection Incidence ◽  
Significant Difference ◽  
Geographic Populations ◽  
Different Populations ◽  
Symbiont Species ◽  
Antagonistic Interactions

Abstract Background Co-infection of endosymbionts in the same host is ubiquitous, and the interactions of the most common symbiont Wolbachia with other symbionts, including Spiroplasma et al., in invertebrate organisms have received increasing attention. However, the interactions between Wolbachia and Arsenophonus, another widely distributed symbiont in nature, are poorly understood. We tested the co-infection of Wolbachia and Arsenophonus in different populations of Nilaparvata lugens and investigated whether co-infection affected the population size of the symbionts in their host. Results A significant difference was observed in the co-infection incidence of Wolbachia and Arsenophonus among 5 populations of N. lugens from China, with nearly half of the individuals in the Zhenjiang population harbouring the two symbionts simultaneously, and the rate of occurrence was significantly higher than that of the other 4 populations. The Arsenophonus density in the superinfection line was significantly higher only in the Maanshan population compared with that of the single-infection line. Differences in the density of Wolbachia and Arsenophonus were found in all the tested double-infection lines, and the dominant symbiont species varied with the population only in the Nanjing population, with Arsenophonus the overall dominant symbiont. Conclusions Wolbachia and Arsenophonus could coexist in N. lugens, and the co-infection incidence varied with the geographic populations. Antagonistic interactions were not observed between Arsenophonus and Wolbachia, and the latter was the dominant symbiont in most populations.

scholarly journals Prognostic factors in glioblastoma multiforme

2010 ◽  
Vol 29 (04) ◽  
pp. 121-125 ◽  
Author(s):  
Leonardo Welling ◽  
José Carlos Lynch ◽  
Celestino Pereira ◽  
Ricardo Andrade ◽  
Fabiana Polycarpo Hidalgo ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Glioblastoma Multiforme ◽  
Retrospective Analysis ◽  
Tumor Volume ◽  
Standard Treatment ◽  
Karnofsky Performance Status ◽  
Performance Status ◽  
Surgical Techniques ◽  
The Other ◽  
Tumor Removal

Abstract Objective: To study if the prognosis variables such as age, the Karnofsky Performance Status (KPS), extension of tumor removal by surgery, radiotherapy and tumor volume influenced the survival of patients with glioblastoma multiforme (GBM). Method: Retrospective analysis of GBM patients operated at Hospital dos Servidores do Estado between 1998 and 2008. Results: We could observe that age, the KPS and radiotherapy influenced the survival. The other variables did not have any prognosis implications. Conclusions: Despite many researches and many improvements regarding the diagnosis and the surgical techniques, the survival of patients with GBM has not changed in the last 30 years and is a therapeutic challenge. The surgical resection followed by radiotherapy is the standard treatment for patients with GBM. The importance of each variable in the patient's prognosis is still to be established in the multivariate analyzes.

A positive allelopathic effect of corn cockle, Agrostemma githago, on wheat, Triticum aestivum

1992 ◽  
Vol 70 (9) ◽  
pp. 1916-1918 ◽  
Author(s):  
Bodil Søgaard ◽  
Hans Doll
Keyword(s):  
Triticum Aestivum ◽  
Key Words ◽  
Growth Stimulation ◽  
Growth Chamber ◽  
Allelopathic Effect ◽  
Grain Production ◽  
Wheat Production ◽  
Key Words Growth ◽  
Seedling Length ◽  
Adult Plants

The effect of corn cockle on wheat was studied during germination and on adult plants in a growth chamber. Seedling length of wheat germinated together with corn cockle for 5 days increased 13%. Wheat growing together with corn cockle in pots to maturity had a statistically significant higher wheat biomass and grain production than wheat growing alone. However, two other experiments with adult plants harvested before wheat maturity showed no effect of corn cockle on wheat production per pot. Within the pots the presence of corn cockle influenced wheat in all three experiments. Wheat plants growing at the same position as a corn cockle plant were 20 to 50% larger than wheat plants standing alone. Key words: growth stimulation, allelopathy, competition, interference.

Weed Control in Soybean (Glycine max) with Flumetsulam, Cloransulam, and Diclosulam

1999 ◽  
Vol 13 (4) ◽  
pp. 791-798 ◽  
Author(s):  
David R. Shaw ◽  
Andrew C. Bennett ◽  
Donald L. Grant
Keyword(s):  
Glycine Max ◽  
Weed Control ◽  
Standard Treatment ◽  
The Other ◽  
Early Season ◽  
Late Season ◽  
Pitted Morningglory

Cloransulam postemergence (POST), diclosulam preemergence (PRE), and flumetsulam preplant incorporated (PPI) and POST were evaluated in six trials at two locations for control of sicklepod and pitted morningglory in soybean. Sicklepod control with cloransulam plus flumetsulam POST was equivalent to chlorimuron POST in seven of eight comparisons both 3 and 6 wk after treatment. Sicklepod control with cloransulam POST was equivalent to chlorimuron in only three of eight comparisons 3 wk after treatment, but late-season control was equivalent in five of six comparisons. Pitted morningglory control with cloransulam alone or in tank-mixture with flumetsulam POST was equivalent to chlorimuron in all comparisons. Control of sicklepod and pitted morningglory was greater in most comparisons when a POST application followed flumetsulam plus trifluralin PPI compared to only trifluralin PPI. In a total PRE stale seedbed system, where all treatments were tank-mixed with pendimethalin plus glyphosate, sicklepod control with all rates of flumetsulam and 26 or 35 g ai/ha diclosulam was equivalent to the standard treatment of imazaquin or metribuzin plus chlorimuron. None of the total PRE programs controlled sicklepod as well as when glyphosate was applied sequentially POST. Pitted morningglory was controlled 83 to 93% with 26 or 35 g/ha diclosulam, equivalent to imazaquin, metribuzin plus chlorimuron, or sequential glyphosate applications 8 wk after the PRE application. Increasing flumetsulam rate increased pitted morningglory control early season, but flumetsulam was not as effective as the other herbicides.

scholarly journals Taste receptor polymorphisms and longevity: a systematic review and meta-analysis

2020 ◽  
Author(s):  
Danilo Di Bona ◽  
Alberto Malovini ◽  
Giulia Accardi ◽  
Anna Aiello ◽  
Giuseppina Candore ◽  
...  
Keyword(s):  
Systematic Review ◽  
Bitter Taste ◽  
Meta Analysis ◽  
Taste Receptor ◽  
The Other ◽  
Analytic Approach ◽  
Taste Receptors ◽  
South Italy ◽  
Physiological Processes ◽  
Different Populations

AbstractBitter taste receptors (TAS2R) are involved in a variety of non-tasting physiological processes, including immune-inflammatory ones. Therefore, their genetic variations might influence various traits. In particular, in different populations of South Italy (Calabria, Cilento, and Sardinia), polymorphisms of TAS2R16 and TAS238 have been analysed in association with longevity with inconsistent results. A meta-analytic approach to quantitatively synthesize the possible effect of the previous variants and, possibly, to reconcile the inconsistencies has been used in the present paper. TAS2R38 variants in the Cilento population were also analysed for their possible association with longevity and the obtained data have been included in the relative meta-analysis. In population from Cilento no association was found between TAS2R38 and longevity, and no association was observed as well, performing the meta-analysis with data of the other studies. Concerning TAS2R16 gene, instead, the genotype associated with longevity in the Calabria population maintained its significance in the meta-analysis with data from Cilento population, that, alone, were not significant in the previously published study. In conclusion, our results suggest that TAS2R16 genotype variant is associated with longevity in South Italy.

scholarly journals A revision of the Pyura stolonifera species complex (Tunicata, Ascidiacea), with a description of a new species from Australia

Zootaxa ◽  
2011 ◽  
Vol 2754 (1) ◽  
pp. 27 ◽  
Author(s):  
MARC RIUS ◽  
PETER R. TESKE
Keyword(s):  
New Species ◽  
Species Complex ◽  
Taxonomic Status ◽  
Single Species ◽  
Distinct Species ◽  
The Other ◽  
Solitary Ascidian ◽  
Different Populations ◽  
A New Species ◽  
Dorsal Tubercle

Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.

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