scholarly journals Cross-locational experiments to reveal yield potential and yield-determining factors of the rice cultivar ‘Hokuriku 193’ and climatic factors to achieve high brown rice yield over 1.2kg m-2 at Nagano in central inland of Japan

2021 ◽  
pp. 1-17
Author(s):  
Masaki Okamura ◽  
Jun Hosoi ◽  
Kenji Nagata ◽  
Kentaro Koba ◽  
Daisuke Sugiura ◽  
...  
Keyword(s):  
Rice Yield ◽  
Climatic Factors ◽  
Brown Rice ◽  
Rice Cultivar ◽  
Yield Potential ◽  
Determining Factors

scholarly journals Insecticide Seed Treatments Partially Safen Rice to Low Rates of Glyphosate and Imazethapyr

2018 ◽  
Vol 32 (5) ◽  
pp. 520-525
Author(s):  
Steven M. Martin ◽  
Jason K. Norsworthy ◽  
Robert C. Scott ◽  
Jarrod Hardke ◽  
Gus M. Lorenz ◽  
...  
Keyword(s):  
Seed Treatment ◽  
Field Experiments ◽  
Rice Yield ◽  
Leaf Growth ◽  
Rice Cultivar ◽  
Yield Potential ◽  
Seed Treatments ◽  
Herbicide Treatments ◽  
Added Benefit ◽  
Multiple Field

AbstractEach year there are multiple reports of drift occurrences, and the majority of drift complaints in rice are from imazethapyr or glyphosate. In 2014 and 2015, multiple field experiments were conducted near Stuttgart, AR, and near Lonoke, AR, to evaluate whether insecticide seed treatments would reduce injury from glyphosate or imazethapyr drift or decrease the recovery time following exposure to a low rate of these herbicides. Study I was referred to as the “seed treatment study,” and Study II was the “drift timing study.” In the seed treatment study the conventional rice cultivar ‘Roy J’ was planted, and herbicide treatments included imazethapyr at 10.5 g ai ha–1, glyphosate at 126 g ae ha–1, or no herbicide. Each plot had either a seed treatment of thiamethoxam, clothianidin, chlorantraniliprole, or no insecticide seed treatment. The herbicides were applied at the two- to three-leaf growth stage. Crop injury was assessed 1, 3, and 5 wk after application. Averaged over site-years, thiamethoxam-treated rice had less injury than rice with no insecticide seed treatment at each rating, along with an increased yield. Clothianidin-treated rice had an increased yield over no insecticide seed treatment, but the reduction in injury for both herbicides was less pronounced than in the thiamethoxam-treated plots. Overall, chlorantraniliprole was generally the least effective of the three insecticides in reducing injury from either herbicide and in protecting rice yield potential. A second experiment conducted at Stuttgart, AR, was meant to determine whether damage to rice from glyphosate and imazethapyr was influenced by the timing (15, 30, and 45 d after planting) of exposure to herbicides for thiamethoxam-treated and nontreated rice. There was an overall reduction in injury with the use of thiamethoxam, but the reduction in injury was not dependent on the timing of the drift event. Reduction in damage from physical drift of glyphosate and imazethapyr as well as increased yields over the absence of an insecticide seed treatment appear to be an added benefit.

Change of Rice Yield Gaps and Influential Climatic Factors in Southern China

2013 ◽  
Vol 38 (5) ◽  
pp. 896-903 ◽  
Author(s):  
Quan-Hong SHI ◽  
Jian-Gang LIU ◽  
Zhao-Hua WANG ◽  
Ting-Ting TAO ◽  
Fu CHEN ◽  
...  
Keyword(s):  
Rice Yield ◽  
Climatic Factors ◽  
Southern China ◽  
Yield Gaps

scholarly journals Crop Wild Relatives Crosses: Multi-Location Assessment in Durum Wheat, Barley, and Lentil

Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2283
Author(s):  
Noureddine El Haddad ◽  
Miguel Sanchez-Garcia ◽  
Andrea Visioni ◽  
Abderrazek Jilal ◽  
Rola El Amil ◽  
...  
Keyword(s):  
Durum Wheat ◽  
Protein Content ◽  
Climatic Factors ◽  
Selection Index ◽  
Crop Wild Relatives ◽  
Wild Relatives ◽  
Yield Potential ◽  
Zn Concentration ◽  
Zn Content ◽  
Dryland Crops

Crop wild relatives (CWR) are a good source of useful alleles for climate change adaptation. Here, 19 durum wheat, 24 barley, and 24 lentil elites incorporating CWR in their pedigrees were yield tested against commercial checks across 19 environments located in Morocco, Ethiopia, Lebanon, and Senegal. For each crop, the combined analysis of variance showed that genotype (G), environment (E), and genotype x environment (GxE) effects were significant for most of the traits. A selection index combining yield potential (G) and yield stability (GxE) was used to identify six CWR-derived elites for each crop matching or superior to the best check. A regression analysis using a climate matrix revealed that grain yield was mostly influenced by the maximum daily temperature and soil moisture level during the growing stages. These climatic factors were used to define five clusters (i.e., E1 to E5) of mega-environments. The CWR-derived elites significantly outperformed the checks in E1, E2, and E4 for durum wheat, and in E2 for both barley and lentil. The germplasm was also assessed for several food transformation characteristics. For durum wheat, one accession (Zeina) originating from T. araraticum was significantly superior in mixograph score to the best check, and three accessions originating from T. araraticum and T. urartu were superior for Zn concentration. For barley, 21 accessions originating from H. spontaneum were superior to the checks for protein content, six for Zn content, and eight for β-glucan. For lentil, ten accessions originating from Lens orientalis were superior to the check for protein content, five for Zn, and ten for Fe concentration. Hence, the results presented here strongly support the use of CWR in breeding programs of these three dryland crops, both for adaptation to climatic stresses and for value addition for food transformation.

scholarly journals A Combined Method of Image Processing and Artificial Neural Network for the Identification of 13 Iranian Rice Cultivars

Agronomy ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 117 ◽  
Author(s):  
Yousef Abbaspour-Gilandeh ◽  
Amir Molaee ◽  
Sajad Sabzi ◽  
Narjes Nabipur ◽  
Shahaboddin Shamshirband ◽  
...  
Keyword(s):  
Neural Network ◽  
Image Processing ◽  
Brown Rice ◽  
Principal Component ◽  
Rice Cultivar ◽  
Rice Cultivars ◽  
Texture Properties ◽  
Effective Components ◽  
Significant Difference ◽  
Artificial Neural

Due to the importance of identifying crop cultivars, the advancement of accurate assessment of cultivars is considered essential. The existing methods for identifying rice cultivars are mainly time-consuming, costly, and destructive. Therefore, the development of novel methods is highly beneficial. The aim of the present research is to classify common rice cultivars in Iran based on color, morphologic, and texture properties using artificial intelligence (AI) methods. In doing so, digital images of 13 rice cultivars in Iran in three forms of paddy, brown, and white are analyzed through pre-processing and segmentation of using MATLAB. Ninety-two specificities, including 60 color, 14 morphologic, and 18 texture properties, were identified for each rice cultivar. In the next step, the normal distribution of data was evaluated, and the possibility of observing a significant difference between all specificities of cultivars was studied using variance analysis. In addition, the least significant difference (LSD) test was performed to obtain a more accurate comparison between cultivars. To reduce data dimensions and focus on the most effective components, principal component analysis (PCA) was employed. Accordingly, the accuracy of rice cultivar separations was calculated for paddy, brown rice, and white rice using discriminant analysis (DA), which was 89.2%, 87.7%, and 83.1%, respectively. To identify and classify the desired cultivars, a multilayered perceptron neural network was implemented based on the most effective components. The results showed 100% accuracy of the network in identifying and classifying all mentioned rice cultivars. Hence, it is concluded that the integrated method of image processing and pattern recognition methods, such as statistical classification and artificial neural networks, can be used for identifying and classification of rice cultivars.

Rice and red rice interference. II. Rice response to population densities of three red rice (Oryza sativa) ecotypes

Weed Science ◽  
2005 ◽  
Vol 53 (5) ◽  
pp. 683-689 ◽  
Author(s):  
Leopoldo E. Estorninos ◽  
David R. Gealy ◽  
Edward E. Gbur ◽  
Ronald E. Talbert ◽  
Marilyn R. McClelland
Keyword(s):  
Aboveground Biomass ◽  
Growth Response ◽  
Field Experiments ◽  
Rice Yield ◽  
Rice Cultivar ◽  
Growth And Yield ◽  
Red Rice ◽  
Population Densities ◽  
Rice Growth ◽  
Tiller Density

Red rice, which grows taller and produces more tillers than domestic rice and shatters most of its seeds early, is a major weed in many rice-growing areas of the world. Field experiments were conducted at Stuttgart, AR in 1997 and 1998 to evaluate the growth response of the Kaybonnet (KBNT) rice cultivar to various population densities of three red rice ecotypes. The ecotypes tested were Louisiana3 (LA3), Stuttgart strawhull (Stgstraw), and Katy red rice (KatyRR). Compared with KBNT alone, LA3, the tallest of the three red rice ecotypes, reduced tiller density of KBNT 51%, aboveground biomass at 91 d after emergence (DAE) 35%, and yield 80%. Stgstraw, a medium-height red rice, reduced KBNT tiller density 49%, aboveground biomass 26%, and yield 61%. KatyRR, the shortest red rice, reduced KBNT tiller density 30%, aboveground biomass 16%, and yield 21%. Tiller density of rice was reduced by 20 to 48% when red rice density increased from 25 to 51 plants m−2. Rice biomass at 91 DAE was reduced by 9 and 44% when red rice densities were 16 and 51 plants m−2. Rice yield was reduced by 60 and 70% at red rice densities of 25 and 51 plants m−2, respectively. These results demonstrate that low populations of red rice can greatly reduce rice growth and yield and that short-statured red rice types may affect rice growth less than taller ecotypes.

scholarly journals Fenologia de Blechnum acutum (Desv.) Mett. (Blechnaceae) em Floresta Atlântica Subtropical (Phenology of Blechnum acutum (Desv.) Mett. (Blechnaceae) in Atlantic Subtropical Forest)

2016 ◽  
Vol 9 (6) ◽  
pp. 1644 ◽  
Author(s):  
Thábia Ottília Hofstetter Padoin ◽  
Andressa Müller ◽  
Jairo Lizandro Schmitt
Keyword(s):  
Atlantic Forest ◽  
Environmental Variables ◽  
Climatic Factors ◽  
Seasonal Pattern ◽  
Subtropical Forest ◽  
Circular Statistics ◽  
Activity Period ◽  
Determining Factors ◽  
The World ◽  
Reproductive Events

O clima de uma área é um dos fatores determinantes da dinâmica da vegetação e a fenologia estuda a ocorrência dos eventos vegetativos e reprodutivos das plantas desencadeados principalmente pela precipitação, temperatura e fotoperíodo. Os estudos fenológicos com samambaias, no mundo, aumentaram nas últimas décadas, porém os seus resultados são geralmente descritivos e restritos a poucos locais e a poucas espécies. Foram determinados o padrão e a sazonalidade das fenofases de Blechnum acutum, em Floresta Atlântica subtropical, relacionando-as com os fatores climáticos, a partir do monitoramento de 20 indivíduos, durante 18 meses. Para verificar a sazonalidade das fenofases foi utilizada a estatística circular. Blechnum acutum apresentou maior intensidade da renovação foliar em janeiro (38%), com maior período de atividade entre janeiro e abril de 2014. A formação de esporângios foi a fenofase que demonstrou o padrão sazonal mais evidente e ocorreu com maior intensidade e atividade em outubro de 2014 (25%). A senescência foliar manifestou maior intensidade em fevereiro de 2014 (23%), com 80% dos indivíduos encontrando-se nesta fenofase, em março de 2015. Os padrões fenológicos não demonstraram a mesma continuidade e regularidade em decorrência principalmente da falta de homogeneidade na manifestação da renovação e senescência das folhas pelos indivíduos na população. Os ritmos fenológicos de B. acutum também não foram igualmente influenciados pelas variáveis ambientais analisadas, sendo que a renovação foliar foi a única fenofase relacionada com temperatura e fotoperíodo.     A B S T R A C T The climate of an area is one of the determining factors of the vegetation’s dynamics and phenology studies. The occurrence of vegetative and reproductive events of plants mainly triggered by rainfall, temperature and photoperiod. The phenological studies with ferns in the world have increased in recent decades, but the results are usually descriptive and restricted to few places and few species. It was determined the pattern and seasonality of phenophases of Blechnum acutum in subtropical Atlantic Forest, relating them to the climatic factors, from monitoring 20 individuals for 18 months. To check the seasonality of phenophases the circular statistics were used. Blechnum acutum showed greater intensity of foliar renovation in January (38%), with higher activity period between January and April 2014. The sporangia formation was the phenophase that showed the most obvious seasonal pattern and was more intense and activity in October 2014 (25%). The leaf senescence showed greater intensity in February 2014 (23%), with 80% of individuals meeting in this phenophase in March 2015. The phenological patterns did not show the same continuity and regularity mainly due to the lack of homogeneity in the manifestation renewal and senescence of leaves by individuals in the population. The phenological rhythms of B. acutum were not also influenced by environmental variables, and the leaf renewal was the only phenophase related to temperature and photoperiod. Keywords: climate, photoperiod, sazonality, phenophase, fern.[1]                                                            

Sign in / Sign up

Export Citation Format

Share Document