Short communication: Evaluation of a model for predicting Avena fatua and Descurainia sophia seed emergence in winter rapeseed

Avena fatua and Descurainia sophia are two important annual weeds throughout winter rapeseed (Brassica napus L.) production systems in the semiarid region of Iran. Timely and more accurate control of both species may be developed if there is a better understanding of its emergence patterns. Non-linear regression techniques are usually unable to accurately predict field emergence under such environmental conditions. The objectives of this research were to evaluate the emergence patterns of A. fatua and D. sophia and determine if emergence could be predicted using cumulative soil thermal time in degree days (CTT). In the present work, cumulative seedling emergence from a winter rapeseed field during 3 year data set was fitted to cumulative soil CTT using Weibull and Gompertz functions. The Weibull model provided a better fit, based on coefficient of determination (R2sqr), root mean square of error (RMSE) and Akaike index (AICd), compared to the Gompertz model between 2013 and 2016 seasons for both species. Maximum emergence of A. fatua occured 70-119 days after sowing or after equals 329-426 °Cd, while in D. sophia it occurred 119-134 days after sowing rapeseed equals 373-470 °Cd. Both models can aid in the future study of A. fatua and D. sophia emergence and assist growers and agricultural professionals with planning timely and more accurate A. fatua and D. sophia control.

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Development and evaluation of Diplotaxis muralis (mur) cytoplasmic male sterility system in summer rape

Canadian Journal of Plant Science ◽

10.4141/p02-093 ◽

2003 ◽

Vol 83 (2) ◽

pp. 261-269 ◽

Cited By ~ 1

Author(s):

T. C. Riungu ◽

P. B. E. McVetty

Keyword(s):

Male Sterility ◽

Floral Morphology ◽

Seedling Emergence ◽

Temperature Stability ◽

Line Pair ◽

Male Sterile ◽

Maintainer Line ◽

Brassica Napus L ◽

Pair Comparisons ◽

Winter Rapeseed

The Diplotaxis muralis male sterility inducing cytoplasm (mur cytoplasm) and its maintainer genes were transferred from the winter rapeseed male sterile line Mangun mur CMS A-line and the mur CMS maintainer line Mangun mur CMS B-line, respectively, into summer rape lines genetically related to the open-pollinated population cultivars Regent and Karat using standard cross, backcross and test cross breeding procedures. Three genetically identical summer rape mur CMS A-line and B-line pairs, Karat I A-line and B-line, Karat II A-line and B-line and Regent A-line and B line were developed. Flower morphology studies revealed that the mur CMS A-lines had anthers displaying a complete absence of pollen and floral morphology modifications similar to that seen for other CMS systems in summer rape. Seedling emergence, days to first flower, days to maturity, and height of the vernalized mur CMS Mangun A-line and B-line pair and the summer rape mur CMS A-line and B-line pairs were similar among treatments and equal for A-line and B-line pair comparisons within cultivars for plants grown in the greenhouse. There was no evidence of biological benefits or costs associated with the mur cytoplasm. The male sterility for the vernalized Mangun mur CMS A-line and the summer rape mur CMS A-lines was stable at temperatures up to 30/24EC. Key words: Brassica napus L., male sterility, temperature stability

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Quality and germination of rapeseed and canola seed damaged by adult cabbage seedpod weevil, Ceutorhynchus assimilis (Paykull) [Coleoptera: Curculionidae]

Canadian Journal of Plant Science ◽

10.4141/cjps95-093 ◽

1995 ◽

Vol 75 (2) ◽

pp. 539-541 ◽

Cited By ~ 25

Author(s):

G. D. Buntin ◽

J. P. McCaffrey ◽

P. L. Raymer ◽

J. Romero

Keyword(s):

Brassica Napus ◽

Seed Weight ◽

Seedling Emergence ◽

Canola Seed ◽

Brassica Napus L ◽

Ceutorhynchus Assimilis ◽

Abnormal Growth ◽

Adult Feeding ◽

Winter Rapeseed ◽

Cabbage Seedpod Weevil

Adult feeding injury by the cabbage seedpod weevil (Ceutorhynchus assimilis Paykull) on pods and seeds of winter rapeseed and canola (Brassica napus L.) in Georgia and Idaho reduced seed weight and oil content an average of 16.2 and 2.2%, respectively. Injury also reduced seed germination by 40.5%, increased me proportion of germinated seed with abnormal growth and reduced seedling emergence from soil. Key words: Insecta, Ceutorhynchus assimilis, canola, rapeseed, Brassica napus, seed injury

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Correlation between the structure and skin permeability of compounds

Scientific Reports ◽

10.1038/s41598-021-89587-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ruolan Zeng ◽

Jiyong Deng ◽

Limin Dang ◽

Xinliang Yu

Keyword(s):

Large Data ◽

Qsar Model ◽

Coefficient Of Determination ◽

Support Vector ◽

Skin Permeability ◽

Data Set ◽

Test Set ◽

Svm Algorithm ◽

Svm Model ◽

Toxicity Relationship

AbstractA three-descriptor quantitative structure–activity/toxicity relationship (QSAR/QSTR) model was developed for the skin permeability of a sufficiently large data set consisting of 274 compounds, by applying support vector machine (SVM) together with genetic algorithm. The optimal SVM model possesses the coefficient of determination R2 of 0.946 and root mean square (rms) error of 0.253 for the training set of 139 compounds; and a R2 of 0.872 and rms of 0.302 for the test set of 135 compounds. Compared with other models reported in the literature, our SVM model shows better statistical performance in a model that deals with more samples in the test set. Therefore, applying a SVM algorithm to develop a nonlinear QSAR model for skin permeability was achieved.

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Unravelling the Complex Interplay of Transcription Factors Orchestrating Seed Oil Content in Brassica napus L.

International Journal of Molecular Sciences ◽

10.3390/ijms22031033 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1033

Author(s):

Abirami Rajavel ◽

Selina Klees ◽

Johanna-Sophie Schlüter ◽

Hendrik Bertram ◽

Kun Lu ◽

...

Keyword(s):

Gene Expression ◽

Transcription Factors ◽

Brassica Napus ◽

Oil Content ◽

Seed Oil ◽

Seed Oil Content ◽

Complex Interplay ◽

Brassica Napus L ◽

Data Set ◽

Developmental Switches

Transcription factors (TFs) and their complex interplay are essential for directing specific genetic programs, such as responses to environmental stresses, tissue development, or cell differentiation by regulating gene expression. Knowledge regarding TF–TF cooperations could be promising in gaining insight into the developmental switches between the cultivars of Brassica napus L., namely Zhongshuang11 (ZS11), a double-low accession with high-oil- content, and Zhongyou821 (ZY821), a double-high accession with low-oil-content. In this regard, we analysed a time series RNA-seq data set of seed tissue from both of the cultivars by mainly focusing on the monotonically expressed genes (MEGs). The consideration of the MEGs enables the capturing of multi-stage progression processes that are orchestrated by the cooperative TFs and, thus, facilitates the understanding of the molecular mechanisms determining seed oil content. Our findings show that TF families, such as NAC, MYB, DOF, GATA, and HD-ZIP are highly involved in the seed developmental process. Particularly, their preferential partner choices as well as changes in their gene expression profiles seem to be strongly associated with the differentiation of the oil content between the two cultivars. These findings are essential in enhancing our understanding of the genetic programs in both cultivars and developing novel hypotheses for further experimental studies.

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Genetic and Genome-Wide Association Analysis of Yearling Weight Gain in Israel Holstein Dairy Calves

Genes ◽

10.3390/genes12050708 ◽

2021 ◽

Vol 12 (5) ◽

pp. 708

Author(s):

Moran Gershoni ◽

Joel Ira Weller ◽

Ephraim Ezra

Keyword(s):

Weight Gain ◽

Milk Fat ◽

Variance Components ◽

Complete Data ◽

Variance Component Analysis ◽

Coefficient Of Determination ◽

Birth Date ◽

Analysis Model ◽

Data Set ◽

Genetic Evaluations

Yearling weight gain in male and female Israeli Holstein calves, defined as 365 × ((weight − 35)/age at weight) + 35, was analyzed from 814,729 records on 368,255 animals from 740 herds recorded between 1994 and 2021. The variance components were calculated based on valid records from 2008 through 2017 for each sex separately and both sexes jointly by a single-trait individual animal model analysis, which accounted for repeat records on animals. The analysis model also included the square root, linear, and quadratic effects of age at weight. Heritability and repeatability were 0.35 and 0.71 in the analysis of both sexes and similar in the single sex analyses. The regression of yearling weight gain on birth date in the complete data set was −0.96 kg/year. The complete data set was also analyzed by the same model as the variance component analysis, including both sexes and accounting for differing variance components for each sex. The genetic trend for yearling weight gain, including both sexes, was 1.02 kg/year. Genetic evaluations for yearling weight gain was positively correlated with genetic evaluations for milk, fat, protein production, and cow survival but negatively correlated with female fertility. Yearling weight gain was also correlated with the direct effect on dystocia, and increased yearling weight gain resulted in greater frequency of dystocia. Of the 1749 Israeli Holstein bulls genotyped with reliabilities >50%, 1445 had genetic evaluations. As genotyping of these bulls was performed using several single nucleotide polymorhphism (SNP) chip platforms, we included only those markers that were genotyped in >90% of the tested cohort. A total of 40,498 SNPs were retained. More than 400 markers had significant effects after permutation and correction for multiple testing (pnominal < 1 × 10−8). Considering all SNPs simultaneously, 0.69 of variance among the sires’ transmitting ability was explained. There were 24 markers with coefficients of determination for yearling weight gain >0.04. One marker, BTA-75458-no-rs on chromosome 5, explained ≈6% of the variance among the estimated breeding values for yearling weight gain. ARS-BFGL-NGS-39379 had the fifth largest coefficient of determination in the current study and was also found to have a significant effect on weight at an age of 13–14 months in a previous study on Holsteins. Significant genomic effects on yearling weight gain were mainly associated with milk production quantitative trait loci, specifically with kappa casein metabolism.

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Henbit (Lamium amplexicaule), Common Chickweed (Stellaria media), Shepherd's-Purse (Capsella bursa-pastoris), and Field Pennycress (Thlaspi arvense): Fecundity, Seed Dispersal, Dormancy, and Emergence

Weed Science ◽

10.1614/ws-d-13-00074.1 ◽

2014 ◽

Vol 62 (1) ◽

pp. 97-106 ◽

Cited By ~ 6

Author(s):

Erin C. Hill ◽

Karen A. Renner ◽

Christy L. Sprague

Keyword(s):

Seed Production ◽

Seedling Emergence ◽

Crop Productivity ◽

Seed Fate ◽

Stellaria Media ◽

Thlaspi Arvense ◽

Emergence Patterns ◽

Field Pennycress ◽

Winter Annuals ◽

Winter Annual

Winter annual weeds protect the soil from erosion and retain nutrients during the winter; however, they can also act as a host for crop pests and pathogens and impede planting. Increased knowledge of the reproductive biology and the seed fate of winter annuals would be useful to improve management and crop productivity. The objectives of this research were to determine the recruitment biology of shepherd's-purse, henbit, common chickweed, and field pennycress, including seed production, dispersal, dormancy, and seedling emergence, based on growing degree days (GDD). Henbit was the least prolific of the four weeds studied, producing 800 to 40,000 seeds m−2at naturally occurring densities; shepherd's-purse was the most prolific, producing 11,000 to 400,000 seeds m−2with 40 to 230 plants m−2. Fifty percent seed rain occurred for henbit, common chickweed, shepherd's-purse, and field pennycress at 620, 790, 880, and 1300 GDDBase,0C, respectively. Overall, seeds were dormant for all species at the time of dispersal. In 2 of 3 yr, dormancy of later-dispersed common chickweed decreased after 6 mo of storage at natural, fluctuating temperatures in the absence of water. The emergence patterns of the four species followed the Gompertz equation and were indicative of facultative winter annuals. The emergence patterns by rate were similar between henbit and common chickweed and between shepherd's-purse and field pennycress. Seed production, dispersal, dormancy, and seedling emergence were influenced by moisture; therefore, including a precipitation or soil moisture component into a GDD model (such as the use of hydrothermal time) would improve the accuracy of predicting winter annual reproduction, seed fate, and emergence.

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Development of a semi-parametric PAR (Photosynthetically Active Radiation) partitioning model for the United States, version 1.0

Geoscientific Model Development ◽

10.5194/gmd-7-2477-2014 ◽

2014 ◽

Vol 7 (5) ◽

pp. 2477-2484 ◽

Cited By ~ 3

Author(s):

J. C. Kathilankal ◽

T. L. O'Halloran ◽

A. Schmidt ◽

C. V. Hanson ◽

B. E. Law

Keyword(s):

United States ◽

Elevation Angle ◽

Model Performance ◽

Diffuse Radiation ◽

The United States ◽

Polynomial Model ◽

Coefficient Of Determination ◽

Data Set ◽

Cubic Polynomial ◽

Solar Elevation Angle

Abstract. A semi-parametric PAR diffuse radiation model was developed using commonly measured climatic variables from 108 site-years of data from 17 AmeriFlux sites. The model has a logistic form and improves upon previous efforts using a larger data set and physically viable climate variables as predictors, including relative humidity, clearness index, surface albedo and solar elevation angle. Model performance was evaluated by comparison with a simple cubic polynomial model developed for the PAR spectral range. The logistic model outperformed the polynomial model with an improved coefficient of determination and slope relative to measured data (logistic: R2 = 0.76; slope = 0.76; cubic: R2 = 0.73; slope = 0.72), making this the most robust PAR-partitioning model for the United States currently available.

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Site-specific wild oat (Avena fatua L.) management

Canadian Journal of Plant Science ◽

10.4141/cjps2012-007 ◽

2012 ◽

Vol 92 (5) ◽

pp. 923-931 ◽

Cited By ~ 5

Author(s):

H. J. Beckie ◽

S. Shirriff

Keyword(s):

Specific Treatment ◽

Triticum Aestivum L ◽

Avena Fatua ◽

Slope Position ◽

Wild Oat ◽

Herbicide Application ◽

Brassica Napus L ◽

Site Specific ◽

Lower Slope ◽

Upper Slope

Beckie, H. J. and Shirriff, S. 2012. Site-specific wild oat ( Avena fatua L.) management. Can. J. Plant Sci. 92: 923–931. Variation in soil properties, such as soil moisture, across a hummocky landscape may influence wild oat emergence and growth. To evaluate wild oat emergence, growth, and management according to landscape position, a study was conducted from 2006 to 2010 in a hummocky field in the semiarid Moist Mixed Grassland ecoregion of Saskatchewan. The hypothesis tested was that wild oat emergence and growth would be greater in lower than upper slope positions under normal or dry early growing season conditions. Three herbicide treatments were imposed on the same plots each year of a 2-yr canola (Brassica napus L.) – wheat (Triticum aestivum L.) sequence: (1) nontreated (weedy) control; (2) herbicide application to upper and lower slope positions (i.e., full or blanket application); and (3) herbicide application to lower slope position only. Slope position affected crop and weed densities before in-crop herbicide application in years with dry spring growing conditions. Site-specific wild oat herbicide application in hummocky fields in semiarid regions may be justified based on results of wild oat control averaged across slope position. In year 2 of the crop sequence (wheat), overall (i.e., lower and upper slope) wild oat control based on density, biomass, and dockage (i.e., seed return) was similar between site-specific and full herbicide treatment in 2 of 3 yr. Because economic thresholds have not been widely adopted by growers in managing wild oat, site-specific treatment in years when conditions warrant may be an appropriate compromise between no application and blanket herbicide application.

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Factors affecting Cyperus difformis seed germination and seedling emergence

Planta Daninha ◽

10.1590/s0100-83582013000400008 ◽

2013 ◽

Vol 31 (4) ◽

pp. 823-832 ◽

Cited By ~ 7

Author(s):

A. Derakhshan ◽

J. Gherekhloo

Keyword(s):

Seed Germination ◽

Integrated Management ◽

Germination Rate ◽

Seedling Emergence ◽

Management Strategies ◽

Soil Surface ◽

Weed Species ◽

Factors Affecting ◽

Cyperus Difformis ◽

Emergence Patterns

Specific knowledge about the dormancy, germination, and emergence patterns of weed species aids the development of integrated management strategies. Laboratory studies were conducted to determine the effect of several environmental factors on seed germination and seedling emergence of Cyperus difformis. Germination of freshly harvested seeds was inhibited by darkness; however, when seeds were subsequently transferred to complete light they germinated readily. Our results showed that 2 wk of cold stratification overcome the light requirement for germination. Seeds of C. difformis were able to germinate over a broad range of temperatures (25/15, 30/20, 35/25, and 40/30 ºC day/night). The response of germination rate to temperature was described as a non-linear function. Based on model outputs, the base, the optimum and the ceiling temperatures were estimated as 14.81, 37.72 and 45 ºC, respectively. A temperature of 120 ºC for a 5 min was required to inhibit 50% of maximum germination. The osmotic potential and salinity required for 50% inhibition of maximum germination were -0.47 MPa and 135.57 mM, respectively. High percentage of seed germination (89%) was observed at pH=6 and decreased to 12% at alkaline medium (pH 9) pH. Seeds sown on the soil surface gave the greatest percentage of seedling emergence, and no seedlings emerged from seeds buried in soil at depths of 1 cm.

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