scholarly journals PERANAN TOKSIN YANG DIHASILKAN OLEH BOTRYODIPLODIA THEOBROMAE DALAM MENIMBULKAN PENYAKIT DIPLODIA PADA BEBERAPA JENIS JERUK

2009 ◽  
Vol 9 (2) ◽  
pp. 158-167
Author(s):  
Salamiah Salamiah
Keyword(s):  
Sweet Orange ◽  
Toxin Production ◽  
Botryodiplodia Theobromae ◽  
Pests And Diseases ◽  
Crude Toxin ◽  
Necrotic Symptom ◽  
Leaf Necrosis ◽  
And Mathematics ◽  
Citrus Leaves

Role of toxin produced by Botryodiplodia theobromae causes Diplodia Bark Diseases on some citrus.  The purpose of the research was to study the role of toxin produced by Botryodiplodia theobromae causes diplodia bark diseases on some citrus. Research was conducted from March through November 2007.  The experiment was done at the laboratory and at a glass house of the Department of Plant Pests and Diseases of the Faculty of Agriculture and the laboratory of the Faculty of Science and Mathematics Lambung Mangkurat University in Banjarbaru.  For a leaf-necrosis bioassay of crude toxin production, the surfaces of the leaves were scratched near the center with a needle, and culture filtrate samples (50 µl) were placed on each wounded site.  Treated leaves were incubated in a moist chamber with light at 26oC for 4 days, and toxin activity was determined by induction of veinal necrosis on the seven susceptible cultivar of citrus.  The results of the experiment showed that the B. theobromae pathogens produced the toxin. The crude toxin was bioassayed for leaf necrosis to determine their ability to produce toxin.  Culture filtrates of the isolate were highly toxic only on five susceptible citrus leaves siam Banjar citrus, sweet orange, lime, kaffir lime, and sour lime,  indicating that the B. theobromae can produced toxin.  Pathogenicity and toxin production of B. theobromae did not differ among different cultivar.  While, no necrotic symptom produces on the pummelo and sunkist.  Toxin production of B. theobromae  produced during spore germination.

scholarly journals Perkembangan Penyakit Diplodia pada Tiga Isolat Botryodiplodia theobromae Path dan Peran Toksin Dalam Menekan Penyakit pada Jeruk (Citrus spp.)

2018 ◽  
Vol 27 (2) ◽  
pp. 231 ◽  
Author(s):  
Mutia Erti Dwiastuti ◽  
Gusti Ngurah Ketut Budiarta ◽  
Loekas Soesanto
Keyword(s):  
Incubation Period ◽  
Sweet Orange ◽  
Block Design ◽  
Pathogenicity Test ◽  
Botryodiplodia Theobromae ◽  
Disease Symptoms ◽  
Crude Toxin ◽  
Randomized Block Design ◽  
Necrotic Symptom ◽  
Citrus Varieties

<p>Penyakit diplodia (Botryodiplodia theobromae) pada tanaman jeruk menyebar cukup luas di sentra jeruk Indonesia. Serangan parah penyakit dapat menyebabkan kematian apabila tidak dikendalikan. Tujuan penelitian adalah mengetahui patogenisitas dan peran toksin dari tiga isolat B. theobromae asal Pasuruan dan Magetan pada jeruk siam, pamelo, dan manis. Penelitian dilakukan di Laboratorium dan Rumah Kasa Balai Penelitian Tanaman Jeruk dan Buah Subtropika pada bulan November 2015 – Mei 2016. Penelitian terdiri atas dua percobaan, yaitu uji patogenisitas pada tanaman dan uji toksin kasar pada skala laboratorium. Uji patogenisitas menggunakan rancangan acak kelompok dengan sembilan kombinasi perlakuan terdiri atas tiga jenis isolat, yaitu Mg52A.1, dan Mg39.2 (asal Magetan), Ps8b (asal Pasuruan), serta tiga jenis tanaman jeruk (pamelo, siam, manis). Parameter pengamatan terdiri atas masa inkubasi, jumlah sampel nekrosis, dan luas gejala. Perlakuan pengujian toksin terdiri atas kontrol tanpa toksin, toksin kasar isolat Mg52A.1, toksin kasar isolat Mg39.2, dan toksin kasar isolat Ps8b. Aplikasi toksin dilakukan pada daun tiga varietas jeruk dengan rancangan acak lengkap, tiap perlakuan diulang tiga kali dan masing masing terdiri atas dua daun asal tanaman yang berbeda. Hasil penelitian menunjukkan bahwa masa inkubasi isolat Mg39.2 lebih cepat dibandingkan dengan isolat Mg52A.1 dan Ps8b. Ketiga isolat patogen B. theobromae asal Pasuruan dan Magetan memiliki patogenisitas yang sama dalam menimbulkan gejala penyakit pada jeruk pamelo, siam, dan manis, sedangkan toksin hanya berperan dalam mempercepat masa inkubasi.</p><p>Diplodia disease (Botryodiplodia theobromae) spread quite widely in Indonesia citrus center. Severe attacks of disease can cause death if it not controlled. The purpose of this study was determine the pathogenicity and the effect of toxins from three isolates of B. theobromae origin Pasuruan and Magetan on tangerine, pummelo, and sweet orange varieties. The study was conducted at Indonesian Citrus and Subtropical Research Institute during November 2015 – May 2016. This observation consisted of two experiments that pathogenicity test in screenhouse and crude toxin of patogen test in laboratory. Pathogenicity test used randomized block design arranged as factorial. The first factor was three isolates: Mg52A.1, Mg39.2 (from Magetan), Ps8b (from Pasuruan) and the second factor were kind of citrus (pummelo, tangerine , and sweet orange). The observation parameter consist of the incubation period, the number of necrotic samples and visual symptom. Crude toxin test treatment consists of a control test toxin without toxins, crude toxin Mg52A.1, crude toxin Mg39.2 toxin, crude toxin Ps8b. Application toxin carried out on the three leaf varieties of oranges. Each treatment was repeated three times and each consists of two leaves of different varieties. The results showed that the incubation period Mg39.2 isolates faster than two other isolates. Infection with different isolates and treatment of different citrus varieties shows that it did not different significantly in causing disease symptom of diplodia. Similarly result on crude toxin treatment with three isolates on three varieties showed that it were not different necrotic symptom. Thus the three isolates of pathogens B.theobromae origin from Pasuruan and Magetan have the same pathogenicity in causing disease symptoms in citrus pummelo, tangerine, and sweet orange. Toxin only play a role in accelerating the incubation period.</p>

Working Memory and Number Sense as Predictors of Mathematical (Dis-)Ability

2015 ◽  
Vol 223 (2) ◽  
pp. 102-109 ◽  
Author(s):  
Evelyn H. Kroesbergen ◽  
Marloes van Dijk
Keyword(s):  
Working Memory ◽  
Learning Disabilities ◽  
Spatial Working Memory ◽  
Number Sense ◽  
Mathematical Learning ◽  
Visual Spatial ◽  
Mathematical Learning Disabilities ◽  
Visual Spatial Working Memory ◽  
And Mathematics

Recent research has pointed to two possible causes of mathematical (dis-)ability: working memory and number sense, although only few studies have compared the relations between working memory and mathematics and between number sense and mathematics. In this study, both constructs were studied in relation to mathematics in general, and to mathematical learning disabilities (MLD) in particular. The sample consisted of 154 children aged between 6 and 10 years, including 26 children with MLD. Children performing low on either number sense or visual-spatial working memory scored lower on math tests than children without such a weakness. Children with a double weakness scored the lowest. These results confirm the important role of both visual-spatial working memory and number sense in mathematical development.

scholarly journals Spo0A Suppresses sin Locus Expression in Clostridioides difficile

mSphere ◽  
2020 ◽  
Vol 5 (6) ◽  
Author(s):  
Babita Adhikari Dhungel ◽  
Revathi Govind
Keyword(s):  
Diarrheal Disease ◽  
Toxin Production ◽  
The United States ◽  
Upstream Region ◽  
Pcr Analysis ◽  
Bacterial Cells ◽  
Master Regulator ◽  
Content Type ◽  
Clostridioides Difficile

ABSTRACT Clostridioides difficile is the leading cause of nosocomial infection and is the causative agent of antibiotic-associated diarrhea. The severity of the disease is directly associated with toxin production, and spores are responsible for the transmission and persistence of the organism. Previously, we characterized sin locus regulators SinR and SinR′ (we renamed it SinI), where SinR is the regulator of toxin production and sporulation. The SinI regulator acts as its antagonist. In Bacillus subtilis, Spo0A, the master regulator of sporulation, controls SinR by regulating the expression of its antagonist, sinI. However, the role of Spo0A in the expression of sinR and sinI in C. difficile had not yet been reported. In this study, we tested spo0A mutants in three different C. difficile strains, R20291, UK1, and JIR8094, to understand the role of Spo0A in sin locus expression. Western blot analysis revealed that spo0A mutants had increased SinR levels. Quantitative reverse transcription-PCR (qRT-PCR) analysis of its expression further supported these data. By carrying out genetic and biochemical assays, we show that Spo0A can bind to the upstream region of this locus to regulates its expression. This study provides vital information that Spo0A regulates the sin locus, which controls critical pathogenic traits such as sporulation, toxin production, and motility in C. difficile. IMPORTANCE Clostridioides difficile is the leading cause of antibiotic-associated diarrheal disease in the United States. During infection, C. difficile spores germinate, and the vegetative bacterial cells produce toxins that damage host tissue. In C. difficile, the sin locus is known to regulate both sporulation and toxin production. In this study, we show that Spo0A, the master regulator of sporulation, controls sin locus expression. Results from our study suggest that Spo0A directly regulates the expression of this locus by binding to its upstream DNA region. This observation adds new detail to the gene regulatory network that connects sporulation and toxin production in this pathogen.

scholarly journals The Role of Mental Effort in Fostering Self-Regulated Learning with Problem-Solving Tasks

2020 ◽  
Vol 32 (4) ◽  
pp. 1055-1072 ◽  
Author(s):  
Tamara van Gog ◽  
Vincent Hoogerheide ◽  
Milou van Harsel
Keyword(s):  
Problem Solving ◽  
Self Regulation ◽  
Mental Effort ◽  
Future Research ◽  
Task Sequence ◽  
Self Monitoring ◽  
Self Regulated Learning ◽  
Regulated Learning ◽  
And Mathematics

Abstract Problem-solving tasks form the backbone of STEM (science, technology, engineering, and mathematics) curricula. Yet, how to improve self-monitoring and self-regulation when learning to solve problems has received relatively little attention in the self-regulated learning literature (as compared with, for instance, learning lists of items or learning from expository texts). Here, we review research on fostering self-regulated learning of problem-solving tasks, in which mental effort plays an important role. First, we review research showing that having students engage in effortful, generative learning activities while learning to solve problems can provide them with cues that help them improve self-monitoring and self-regulation at an item level (i.e., determining whether or not a certain type of problem needs further study/practice). Second, we turn to self-monitoring and self-regulation at the task sequence level (i.e., determining what an appropriate next problem-solving task would be given the current level of understanding/performance). We review research showing that teaching students to regulate their learning process by taking into account not only their performance but also their invested mental effort on a prior task when selecting a new task improves self-regulated learning outcomes (i.e., performance on a knowledge test in the domain of the study). Important directions for future research on the role of mental effort in (improving) self-monitoring and self-regulation at the item and task selection levels are discussed after the respective sections.

Role of auxins, polyamines and ethylene in root formation and growth in sweet orange

2011 ◽  
Vol 55 (2) ◽  
pp. 375-378 ◽  
Author(s):  
A. F. S. Mendes ◽  
L. C. Cidade ◽  
W. C. Otoni ◽  
W. S. Soares-Filho ◽  
M. G. C. Costa
Keyword(s):  
Root Formation ◽  
Sweet Orange

Distance Learning

1997 ◽  
Vol 9 (2) ◽  
pp. 89-100 ◽  
Author(s):  
Virginia Wilson ◽  
James Litle ◽  
Mary Ruth Coleman ◽  
James Gallagher
Keyword(s):  
North Carolina ◽  
Distance Learning ◽  
Student Selection ◽  
Educational Setting ◽  
Evaluation Plan ◽  
The North ◽  
North Carolina School ◽  
Studio Classroom ◽  
And Mathematics

As the role of distance learning within the educational setting expands, it is imperative that potential producers and receivers of these courses examine the prospects and problems of a distance learning initiative prior to embarking on this new educational journey. The authors provide guidance from their own distance learning experiences at the North Carolina School of Science and Mathematics. The article focuses on the importance of instructor and facilitator training, student selection, physical arrangements for the studio/classroom, and an evaluation plan.

Role of Women in the Pursuit of NDE 4.0

2021 ◽  
Vol 79 (3) ◽  
pp. 272-284
Author(s):  
Ripi Singh ◽  
Marybeth Miceli
Keyword(s):  
Women Leaders ◽  
Value Chain ◽  
Personal Experience ◽  
Change Leadership ◽  
Science Technology ◽  
Growth Disruption ◽  
Multiple Challenges ◽  
And Mathematics ◽  
Technology Standardization

This paper is intended to highlight roles that women can and likely will play in shaping the future of NDE 4.0, from execution to leadership levels as well as from development to transformation activities. As we build momentum toward adopting Industry 4.0 into the nondestructive evaluation (NDE) domain, we face multiple challenges such as technology standardization, talent and skills shortfall, massive transformation, and regulatory and certification standards (Singh 2019, 2020a). Many of these challenges are better addressed with a proper mix of gender in responsible teams. Women in STEM (science, technology, engineering, and mathematics) fields are a source of talent that can be harnessed as digitalization becomes a major part of the NDE sector. According to a recent Forbes article, traits like listening and empathy serve women well in “change leadership,” which is the ability to influence and inspire action in others and respond with vision and agility during periods of growth, disruption, or uncertainty to bring about the needed change (Lipkin 2019). While working the innovation value chain, emotional intelligence makes women better suited to capturing marketplace insight and easing friction in technology adoption, and a balance of gender in a team makes for more productive ideation sessions for effective problem-solving and objective execution. This paper presents literature research triggered by personal experience and substantiated by recent candid conversations with women leaders in NDE, to highlight the importance of a blended and balanced gender mix required for NDE 4.0.

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