Effect of Egyptian Broomrape (Orobanche aegyptiaca) Seed-Burial Depth on Parasitism Dynamics and Chemical Control in Tomato

Weed Science ◽  
2007 ◽  
Vol 55 (2) ◽  
pp. 152-156 ◽  
Author(s):  
Hanan Eizenberg ◽  
Tal Lande ◽  
Gay Achdari ◽  
Asia Roichman ◽  
Joseph Hershenhorn
Keyword(s):  
Soil Surface ◽  
Burial Depth ◽  
Severe Damage ◽  
Control Efficacy ◽  
Tomato Roots ◽  
Wide Range ◽  
Significant Difference ◽  
Highly Correlated ◽  
The Relationship ◽  
Different Levels

Broomrapes (Orobanche spp.) are chlorophyll-lacking root parasites of many dicotyledonous species that cause severe damage to vegetables and field crops worldwide. Egyptian broomrape is common throughout Israel, where it parasitizes a wide range of crops. The main damage caused by this parasite is to processing tomatoes. The objectives of this study were to determine (1) the relationship between the parasitism process on tomato roots and Egyptian broomrape seed depth, and (2) the effect of herbicide application on Egyptian broomrape control at depths of 0 to 30 cm. The study was conducted in controlled conditions in 25-L pots containing soil that was artificially infested with Egyptian broomrape seeds. Seeds (1-cm layer) were infested at soil surface and at depths of 6, 12, 18, 24, and 30 cm. Sulfosulfuron was applied PRE to Egyptian broomrape shoots, 14 and 42 d after tomato planting. Egyptian broomrape emergence was highly correlated to the depth of the seed infestation: the deeper the seeds were buried, the more pronounced the delay in Egyptian broomrape emergence. A four-parameter sigmoid equation was found that describes the relationship between Egyptian broomrape parasitism and seed depth. No Egyptian broomrape shoots were observed aboveground when sulfosulfuron was applied on tomato foliage. However, live and dead attachments were observed at different levels in all seed-depth treatments. No significant difference in the efficacies of sulfosulfuron at rates of 37.5 and 75 ai ha−1 was observed at depths of 6, 12, and 18 cm. The best control was obtained at a depth of 6 cm at both sulfosulfuron rates. At depths of 24 and 30 cm, no broomrape control was achieved at 37.5 ai g ha−1 sulfosulfuron, and only low control efficacy was obtained at 75 ai g ha−1.

scholarly journals Germination ecology of wild onion: a rainfed crop weed

2014 ◽  
Vol 32 (1) ◽  
pp. 69-80 ◽  
Author(s):  
A. Tanveer ◽  
M. Sibtain ◽  
M.M. Javaid ◽  
H.H. Ali
Keyword(s):  
Environmental Factors ◽  
Osmotic Stress ◽  
Constant Temperature ◽  
Soil Surface ◽  
Burial Depth ◽  
Distilled Water ◽  
Complete Darkness ◽  
Wide Range ◽  
Significant Difference ◽  
Nacl Concentration

Asphodelus tenuifolius is becoming a more common weed in rain-fed area in Pakistan. Laboratory and greenhouse experiments were conducted to determine the effect of different environmental factors on germination and emergence of A.tenuifolius. Results showed that A.tenuifolius can tolerate a wide range of varying environmental factors. Greatest percentage of germination (80%) was recorded at 15 ºC constant temperature; however, considerable germination occurred at 20 and 25 ºC. Light for 10 h photoperiod stimulate germination of Asphodelus tenuifolius compared with complete darkness. Germination was totally inhibited at osmotic stress higher than -0.8 MPa. There was no significant difference in germination at pH 6 to 8; however, there was a slightly decrease at pH 9, compared with distilled water. Asphodelus tenuifolius was very sensitive to salinity; however, a few seeds of A.tenuifolius were able to germinate even at 150 mM NaCl concentration. Greatest emergence occurred with seed placed at soil surface and emergence decreased with increase in burial depth. No emergence occurred from 4 cm or greater. This information may aid in developing tools and strategies for management.

Effect of Environmental Factors on Germination and Emergence of Shortawn Foxtail (Alopecurus aequalis)

Weed Science ◽  
2017 ◽  
Vol 66 (1) ◽  
pp. 47-56 ◽  
Author(s):  
Ning Zhao ◽  
Qi Li ◽  
Wenlei Guo ◽  
Lele Zhang ◽  
Lu’an Ge ◽  
...  
Keyword(s):  
Seed Germination ◽  
Osmotic Potential ◽  
Control Strategies ◽  
Abiotic Factors ◽  
Germination Rate ◽  
Seedling Emergence ◽  
Soil Surface ◽  
Burial Depth ◽  
Effective Measure ◽  
Wide Range

Shortawn foxtail is an invasive grass weed infesting winter wheat and canola production in China. A better understanding of the germination ecology of shortawn foxtail would help to develop better control strategies for this weed. Experiments were conducted under laboratory conditions to evaluate the effects of various abiotic factors, including temperature, light, pH, osmotic stress, salt concentration, and planting depth, on seed germination and seedling emergence of shortawn foxtail. The results showed that the seed germination rate was greater than 90% over a wide range of constant (5 to 25C) and alternating (15/5 to 35/25C) temperatures. Maximum germination occurred at 20C or 25/15C, and no germination occurred at 35C. Light did not appear to have any effect on seed germination. Shortawn foxtail germination was 27% to 99% over a pH range of 4 to 10, and higher germination was obtained at alkaline pH values ranging from 7 to 10. Seed germination was sensitive to osmotic potential and completely inhibited at an osmotic potential of −0.6 MPa, but it was tolerant to salinity: germination even occurred at 200 mM NaCl (5%). Seedling emergence was highest (98%) when seeds were placed on the soil surface but declined with the increasing burial depth. No seedlings emerged when seeds were buried 6-cm deep. Deep tillage could be an effective measure to limit seed germination from increased burial depth. The results of this study will lead to a better understanding of the requirements for shortawn foxtail germination and emergence and will provide information that could contribute to its control.

scholarly journals Assortative Mating, Income Inequality, and Place

2021 ◽  
Author(s):  
◽  
Avril Macfarlane
Keyword(s):  
Income Inequality ◽  
Assortative Mating ◽  
Household Income ◽  
European Social Survey ◽  
Highly Educated ◽  
Wide Range ◽  
Negative Effect ◽  
Educational Assortative Mating ◽  
Highly Correlated ◽  
The Relationship

<p>There is a growing concern internationally about levels of income inequality, and the negative effect this has on the functioning of societies both in terms of productivity and social harmony. An unexpected contributor to inequality is assortative mating - the phenomenon of “like marrying like”. Educational attainment is highly correlated with income; when two highly educated people partner and form a household they are more likely to appear at the top of the household income distribution, while couples with only primary or incomplete secondary education appear at the bottom. Therefore the greater the propensity to mate assortatively the more unequal the distribution of household income becomes.   I ask two questions of the relationship between educational assortative mating and household income inequality. Firstly, how do countries (in Europe) differ in their degree of educational assortative mating? Secondly, what is the evidence that such differences are reflected in indicators of household income inequality?   My study differs from the prevailing approaches to this question by taking a geographical approach. Instead of comparing a single country over time and monitoring the correspondence between assortative mating and income inequality, I compare a wide range of countries, using a uniform instrument, at one point in time. In order to do so I draw on the unit records of 29 countries from the European Social Survey administered in 2012.   From these unit record data I have been able to identify two important patterns. Firstly, there is a clear presence of educational assortative mating in each country. However, the degree differs and it does so primarily as a reflection of the overall level of education in the country. Rising levels of education lower the returns for education, in turn making assortative mating comparatively less attractive. As a result, the level of assortative mating, compared to what would be expected under random conditions, is lower in highly educated nations. The lowered level of assortative mating in highly educated nations reduces the barriers to social mobility through marriage for those without university educations. Consequently, household income inequality is seen to be intrinsically related to assortative mating, although the outcomes can be mitigated by redistribution policies.</p>

scholarly journals Assortative Mating, Income Inequality, and Place

2021 ◽  
Author(s):  
◽  
Avril Macfarlane
Keyword(s):  
Income Inequality ◽  
Assortative Mating ◽  
Household Income ◽  
European Social Survey ◽  
Highly Educated ◽  
Wide Range ◽  
Negative Effect ◽  
Educational Assortative Mating ◽  
Highly Correlated ◽  
The Relationship

<p>There is a growing concern internationally about levels of income inequality, and the negative effect this has on the functioning of societies both in terms of productivity and social harmony. An unexpected contributor to inequality is assortative mating - the phenomenon of “like marrying like”. Educational attainment is highly correlated with income; when two highly educated people partner and form a household they are more likely to appear at the top of the household income distribution, while couples with only primary or incomplete secondary education appear at the bottom. Therefore the greater the propensity to mate assortatively the more unequal the distribution of household income becomes.   I ask two questions of the relationship between educational assortative mating and household income inequality. Firstly, how do countries (in Europe) differ in their degree of educational assortative mating? Secondly, what is the evidence that such differences are reflected in indicators of household income inequality?   My study differs from the prevailing approaches to this question by taking a geographical approach. Instead of comparing a single country over time and monitoring the correspondence between assortative mating and income inequality, I compare a wide range of countries, using a uniform instrument, at one point in time. In order to do so I draw on the unit records of 29 countries from the European Social Survey administered in 2012.   From these unit record data I have been able to identify two important patterns. Firstly, there is a clear presence of educational assortative mating in each country. However, the degree differs and it does so primarily as a reflection of the overall level of education in the country. Rising levels of education lower the returns for education, in turn making assortative mating comparatively less attractive. As a result, the level of assortative mating, compared to what would be expected under random conditions, is lower in highly educated nations. The lowered level of assortative mating in highly educated nations reduces the barriers to social mobility through marriage for those without university educations. Consequently, household income inequality is seen to be intrinsically related to assortative mating, although the outcomes can be mitigated by redistribution policies.</p>

Germination Ecology of Two Australian Populations of African turnipweed (Sisymbrium thellungii)

Weed Science ◽  
2018 ◽  
Vol 66 (6) ◽  
pp. 752-757 ◽  
Author(s):  
Gulshan Mahajan ◽  
Amar Matloob ◽  
Michael Walsh ◽  
Bhagirath S. Chauhan
Keyword(s):  
Seed Germination ◽  
Management Strategies ◽  
Soil Surface ◽  
Wheat Crop ◽  
Burial Depth ◽  
Negative Effects ◽  
Wide Range ◽  
Water Ph ◽  
Winter Crops ◽  
Residue Study

AbstractAfrican turnipweed (Sisymbrium thellungiiO. E.Schulz) is an emerging problematic broadleaf weed of the northern grain region of Australia. Laboratory experiments were conducted to evaluate the effects of temperature, light, salinity, pH, seed burial depth, and the amount of wheat crop residue on germination and emergence of two AustralianS. thellungiiweed populations (population C, cropped area; population F, fence line). Both populations behaved similarly across different environmental conditions, except in the residue study. Although the seeds of both populations ofS. thellungiicould germinate under complete darkness, germination was best (~95%) under light/dark conditions at the 20/10 C temperature regime. Both populations ofS. thellungiigerminated over a wide range of day/night temperatures (15/5, 20/10, 25/15, and 30/20 C). Osmotic stress had negative effects on germination, with 54% seeds (averaged over populations) able to germinate at −0.1MPa. Complete germination inhibition for both populations was observed at −0.8MPa osmotic potential. Both populations germinated at sodium chloride (NaCl) concentrations ranging from 50 to 100 mM, beyond which germination was completely inhibited. There were substantial reductions in seed germination, 32% (averaged over populations) under highly acidic conditions (pH 4.0) as compared with the control (water: pH 6.4). Seed germination of both populations on the soil surface was 77%, and no seedlings emerged from a burial depth of 1 cm. The addition of 6 Mg ha−1of wheat (Triticum aestivumL.) residue reduced the emergence of the C and F populations ofS. thellungiiby 75% and 64%, respectively, as compared with the control (no residue). Information gathered from this study provides a better understanding of the factors favorable for germination and emergence ofS. thellungii, which will aid in developing management strategies in winter crops, especially wheat, barley (Hordeum vulgareL.), and chick pea (Cicer arietinumL.).

Seed germination ecology of Sumatran fleabane (Conyza sumatrensis) in relations to various environmental parameters

Weed Science ◽  
2021 ◽  
pp. 1-26
Author(s):  
Gulshan Mahajan ◽  
Asheneel Prasad ◽  
Bhagirath Singh Chauhan
Keyword(s):  
Seed Germination ◽  
Light Intensity ◽  
Chloride Concentration ◽  
Soil Surface ◽  
Control Treatment ◽  
Effect Of Temperature ◽  
Burial Depth ◽  
Germination Ecology ◽  
Wide Range ◽  
Dark Conditions

Abstract Sumatran fleabane [Conyza sumatrensis (Retz.) Walker] is an emerging weed in the Australian cropping region. Populations resistant to glyphosate have evolved in Australia, creating the demand for information regarding the seed germination ecology of glyphosate-resistant (R) and glyphosate susceptible (S) populations of C. sumatrensis. A study was conducted to examine the effect of temperature, light intensity, salt stress, osmotic stress, and burial depth on the germination and emergence of two populations (R and S) of C. sumatrensis. Both populations were able to germinate over a wide range of alternating day/night temperatures (15/5 to 35/25 C). In light/dark conditions, the R population had higher germination than the S population at 20/10 and 35/25 C. In the dark, the R population had higher germination than the S population at 25/15 C. In the dark, germination was inhibited at 30/20 C and above. Averaged over populations, seed germination of C. sumatrensis was reduced by 97% at zero light intensity (completely dark conditions) compared with full light intensity. Seed germination of C. sumatrensis reduced by 17 and 85% at an osmotic potential of −0.4, and −0.8 MPa, respectively, compared with the control treatment. The R population had lower germination (57%) than the S population (72%) at a sodium chloride concentration of 80 mM. Seed germination was highest on the soil surface and emergence was reduced by 87 and 90% at burial depths of 0.5 and 1.0 cm, respectively. Knowledge gained from this study suggests that a shallow-tillage operation to bury weed seeds in conventional tillage systems, and retention of high residue cover in a zero-till system on the soil surface may inhibit the germination of C. sumatrensis. This study also warrants that the R population may have a greater risk of invasion over a greater part of a year due to germination over a broader temperature range.

Poor Little Rich Kids? The Role of Nature versus Nurture in Wealth and Other Economic Outcomes and Behaviours

2019 ◽  
Vol 87 (4) ◽  
pp. 1683-1725 ◽  
Author(s):  
Sandra E Black ◽  
Paul J Devereux ◽  
Petter Lundborg ◽  
Kaveh Majlesi
Keyword(s):  
Adoptive Parents ◽  
Nature Versus Nurture ◽  
Biological Parents ◽  
Wide Range ◽  
Birth Factors ◽  
Nature And Nurture ◽  
Parental Wealth ◽  
Highly Correlated ◽  
The Relationship

Abstract Wealth is highly correlated between parents and their children; however, little is known about the extent to which these relationships are genetic or determined by environmental factors. We use administrative data on the net wealth of a large sample of Swedish adoptees merged with similar information for their biological and adoptive parents. Comparing the relationship between the wealth of adopted and biological parents and that of the adopted child, we find that, even prior to any inheritance, there is a substantial role for environment and a much smaller role for pre-birth factors and we find little evidence that nature/nurture interactions are important. When bequests are taken into account, the role of adoptive parental wealth becomes much stronger. Our findings suggest that wealth transmission is not primarily because children from wealthier families are inherently more talented or more able but that, even in relatively egalitarian Sweden, wealth begets wealth. We further build on the existing literature by providing a more comprehensive view of the role of nature and nurture on intergenerational mobility, looking at a wide range of different outcomes using a common sample and method. We find that environmental influences are relatively more important for wealth-related variables such as savings and investment decisions than for human capital. We conclude by studying consumption as an overall measure of welfare and find that, like wealth, it is more determined by environment than by biology.

scholarly journals Effect of inguinal hernia on the thickness and blood flow of spermatic cord in boys

2019 ◽  
Vol 2 (2) ◽  
pp. e000030
Author(s):  
Shoujiang Huang ◽  
Canping Li ◽  
Xiuzhen Yang ◽  
Jianfeng Liang ◽  
Dongpi Wang
Keyword(s):  
Blood Flow ◽  
Inguinal Hernia ◽  
Spermatic Cord ◽  
Peak Systolic Velocity ◽  
Control Group ◽  
Pampiniform Plexus ◽  
Significant Difference ◽  
Highly Correlated ◽  
And Control ◽  
The Relationship

ObjectiveTo evaluate the effect of inguinal hernia (IH) on the spermatic cord using spermatic cord ultrasonography (SCU).MethodsFrom January 2016 to January 2017, boys with IH who received SCU at the start of open herniorrhaphy (OH) were enrolled in this study. The age and weight at SCU, width of the spermatic cord (SC-W), peak systolic velocity (PSV) in the spermatic artery (SA-PSV) and velocity in the pampiniform plexus (PP-V), and the interval between the initial and the second OH in boys with metachronous inguinal hernia (MIH) were recorded, and the relationship among them was studied. Boys with unilateral IH comprised the IH group, and boys with MIH comprised the MIH group. Boys with polydactylism served as the control. One-way analysis of variance tested the differences among groups. Spearman’s r tested the relationship between SC-W in the MIH group and the interval.ResultsA total of 80 boys were enrolled in this study (IH group 29, MIH group 26, and control group 25). SA-PSV and PP-V in the hernia side were faster and slower than the control, respectively. There was no significant difference in PP-V and SA-PSV of the treated side in the MIH group and in the control group. After herniorrhaphy, SC-W was tapered down to normal size. SC-W, SA-PSV, and PP-V in the treated side were all highly correlated to the interval in a curvilinear manner.ConclusionPSV was positively correlated with SC-W in boys with IH, and PP-V was negatively correlated; herniorrhaphy could reverse the impairment.

Carboplatin dosing by predictive formulae and factors related to its myelosuppressive toxicity

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e19101-e19101
Author(s):  
S. J. Ayirookuzhi ◽  
J. McLarty ◽  
R. Mansour ◽  
G. M. Mills
Keyword(s):  
Pearson Correlation ◽  
Area Under The Curve ◽  
Stage Iii ◽  
Linear Regression Models ◽  
Cell Counts ◽  
Significant Difference ◽  
Spss Software ◽  
Highly Correlated ◽  
The Relationship ◽  
Carboplatin Dose

e19101 Background: Carboplatin is a commonly used drug in stage III/IV non-small cell lung cancer (NSCLC). Its dose in typically calculated with the Calvert equation that uses the glomerular filtration rate (GFR) from various predictive formulae such as MDRD, Cockroft-Gault, Jeliffe and Wright as well as the targeted area under the curve (AUC) for carboplatin. Myelosuppression is a common toxicity of carboplatin and this study aimed to assess the relationship between dosing and toxicity as well as if there would be any significant difference in dosing based on calculation of GFR from the above formulae in our patient population. Methods: Data from patients with Stage III and IV NSCLC seen between 1/1/99 to 12/31/2007 were analyzed. Patients who received concurrent radiation, who died before the first cycle was completed, as well as patients with missing lab values were excluded. Only the first cycle of the carboplatin based regime was used for analysis with nadir platelets, hemoglobin and wbc's used as endpoints. SPSS software was used for statistical analysis including Pearson correlation, ANCOVA, independent t-tests as well as multivariate linear regression models. Results: Of the 216 patients initially abstracted for analysis only 132 patients were analyzable. Demographically 71 were Caucasian and rest were African-American while 92 were male. The carboplatin dose calculated from all four formulae were highly correlated (p < 0.0001). The drop in the three cell counts were correlated to each other (p< 0.05), particularly the drop in platelet count with other two cell counts. The correlation between the drop in wbc and drop in hemoglobin approached significance (p=0.075). The nadir wbc was significantly associated with BSA (p=0.004), wbc level at baseline (p< 0.000) and approached significance for carboplatin dose (p=0.059) by ANCOVA analysis, while significance was not reached for nadir platelets or nadir hemoglobin. Conclusions: The different predictive equations resulted in similar doses of carboplatin that were statistically significant. BSA correlated significantly with myelosuppression while carboplatin dose only approached significance. No significant financial relationships to disclose.

scholarly journals An Examination of Response of Consumers with Different Levels of Uniqueness to Limited Quantity Offers

2016 ◽  
Vol 41 (3) ◽  
pp. 209-221 ◽  
Author(s):  
Mayank Jyotsna Soni ◽  
Abraham Koshy
Keyword(s):  
Purchase Intention ◽  
Sales Promotion ◽  
Executive Summary ◽  
Need For Uniqueness ◽  
Time Period ◽  
Final Sample ◽  
Significant Difference ◽  
Number Of Customers ◽  
The Relationship ◽  
Different Levels

Executive Summary Marketers try to influence consumers through promotional offers by restricting availability of products to a limited number of customers, a limited time period, or a specific segment, thereby creating a perception of scarcity. Such promotional appeal of making a product or offer scarce is called as scarcity appeal. Literature suggests that people with high need for uniqueness (NFU) prefer scarce products, or at least products which are depleting fast. However, the relationship between scarcity of offers and the NFU has not been much explored. The objective of this research is to understand how consumers with different levels of uniqueness respond to the scarcity appeal offer, especially with discount. Hypotheses relate to variability of purchase intent and attitude towards the product due to scarcity versus no-scarcity sales promotion appeals and by consumers with high and low needs for uniqueness. Proposed hypotheses were tested using 2 × 2 between-subjects factorial design. Quantity scarcity and no-scarcity appeals were manipulated using pre-tested and validated scenarios. Product used in the scenarios (laptop) was identified through an iterative process of seeking inputs from respondents with demographic profile similar to those in the final sample. Consumers’ need for uniqueness (CNFU) purchase intention, and attitude towards product were measured using scales that were pre-tested and validated using accepted protocols. On testing the formulated hypotheses using experimental design, it was found that: Consumers respond more favourably to quantity scarcity appeal offer when compared with no-scarcity appeal offer. Consumers with higher NFU indicate higher purchase intention in a no-scarcity appeal situation when compared with those with low NFU. There is no statistically significant difference in purchase intention of consumers with high and low needs for uniqueness in a situation of scarcity appeal messaging.

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