Applications of response surface methodology approach to determine the effect of temperature, time of incubation and light conditions on germination and germ tube growth of Puccinia coronata f.sp. avenae urediosopores

Crown rust caused by Puccinia coronata f.sp. avenae is the most damaging disease on oat. This work analyzed the effects of temperature and illumination regime during different time of incubation on both spore germination and germ tube growth, using both analysis of variance (ANOVA) and response surface methodology (RSM). This study reveals that the maximum of germination approached 95% under dark conditions at 20°C. Similarly, the maximum germ tube length was 125±23 μm under dark conditions at the same temperature after 18 h. Both spore germination and germ tube growth were observed over a wider temperature range of 5 to 30°C. The darkness conditions seem to enhance significantly (P < 0.05) both the germination and germ tube growth. After 4 h of incubation, germination was significantly higher under darkness regime at 15, 20 and 25°C than under light conditions. The effect of darkness conditions on germ tube growth paralleled its effect on germination. Furthermore, the response surface methodology (RSM) was applied to determine the optimal conditions of temperature, time and illuminations conditions for both the germination process and germ tube growth of urediospores for P. coronata f.sp. coronata. Values for the optimal germination and germ tube growth were 20°C and 8 h under darkness conditions. Moreover, urediospores of P. coronata f.sp. coronata germination and germ tube growth had followed a quadratic response function on temperature (R² = 0.94 and 0.97). On the other hand, the experimental values were in good agreement with the predicted ones and the model was highly significant with the correlation coefficient R being 0.97 and 0.98, respectively for germination and germ tube growth.Key words: Puccinia coronata f.sp. avenae, temperature, time, illuminations conditions, germination process, germ tube growth, urediospores

Analisis Kemampuan Komunikasi Matematis Pembelajaran Operasi Hitung Bilangan Bulat di SMPN

This research the “analysis ability communication see mathematical in studied arithmetic operation occupation number overall in the class VII SMPN 3 Sungai Ambawang” by means of object research for information acquire about (1) ability expressiveness student mathematics idea mathematics drawing to bend, (2) ability student unspecified to deep evident independent clause mathematic, (3) apply ability analysised student in the information. Research method the be descriptive purpose. In bend the study medical. In the research subjek student class VII SMPN 3 Sungai to Ambawang 40 quantity people. On the strength of t is that result research (1) ability student expressiveness mathematics idea drawing to bend appertain until with percentage 56,40%, (2) ability student unspecified to evident deep independent clause mathematic appertain until with percentage 91,71%, (3) analysis information ability student appertain apply in the until with percentage 38, 43%.

Pengaruh Metil Metsulfuron terhadap Sel Darah Merah Ikan Patin Siam (Pangasius Hypopthalmus)

Penggunaan herbisida yang tidak efektif berpotensi menjadi racun pada ikan yang dibudidayakan di area persawahan. Herbisida berbahan aktif metil metsulfuron merupakan herbisida sistemik dan selektif untuk tanaman padi. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi metil metsulfuron 0; 15,6 dan 39 ppm terhadap kerusakan sel darah merah dan persentase hematokrit patin siam (Pangasius hypopthalmus). Hasil penelitian menunjukkan sel darah merah patin siam yang terpapar metil metsulfuron pada konsentrasi 15,6 ppm dan 39 ppm, membentuk lipofuscin pada inti sel, seroid pada permukaan sitoplasma dan nilai hematokrit 19,76 dan 14,80 % sebagai indikasi terjadinya anemia

Analisis Perbandingan Nilai Tambah Pengolahan Ubi Kayu Menjadi Tepung Mocaf dan Tepung Tapioka di Kabupaten Serdang Bedagai (Kasus : Desa Bajaronggi, Kec. Dolok Masihul dan Kec. Sei Rampah)

Penelitian ini bertujuan untuk mengidentifikasi proses pengolahan tepung mocaf dan tapioka, untuk menganalisis pendapatan pelaku USAha, serta menganalisis dan membandingkan nilai tambah pengolahan tepung mocaf dan tapioka di daerah penelitian. Lokasi penelitian terletak di Kabupaten Serdang Bedagai yang ditentukan secara purposive dengan jumlah sampel sebanyak 7 sampel. Data yang digunakan adalah data primer dengan teknis wawancara langsung dengan menggunakan daftar pertanyaan. Metode analisis yang digunakan adalah analisis deskriptif, analisis biaya dan pendapatan, dan analisis nilai tambah. Hasil analisis menunjukkan bahwa pendapatan USAha pengolahan nilai tambah ubi kayu menjadi tepung mocaf lebih rendah dibandingan pendapatan USAha pengolahan ubi kayu menjadi tepung tapioka

Morphological, physiological and pathogenic variability of small-spore Alternaria sp. causing leaf blight of Solanaceous plants in Algeria

Due to premature defoliation, early blight epidemics can cause major yield losses. Large-spore Alternaria species such as A. solani and A. tomatophila have long been recognized as important pathogens responsible for such blight disease in the family Solanaceae and thus represent a serious risk for crop production. Small-spore Alternaria species have also been frequently isolated from plant samples with typical blight symptoms but their incidence as primary pathogens is often controversial. In order to study the diversity of small-spore Alternaria species, 32 isolates were selected from a larger collection of 130 isolates from infected leaves, fruits and stems of tomato from various growing regions of North-West Algeria. Morphological characterization under standard conditions and polymerase chain reaction (PCR) analyses using specific primers to amplify a part of the ITS regions and the 5.8S gene were conducted to confirm their identification as members of the alternata section. They were then examined according to morphological characteristics of conidia and sporulation patterns on potato carrot agar (PCA) and were segregated into three morphological species: A. alternata, A. tenuissima and A. arborescens. Colony type, substrate colour, margin, zonation, pigmentation, colony diameter and conidia production were studied on potato sucrose agar (PSA). Physiological parameters and nutritional requirements of the isolates were also assessed and a data matrix based on cluster analysis and Euclidean distance was constructed. Results of pathogenicity test on tomato showed obvious diversity among the isolates and they could be separated into two groups based on their virulence. The dendrogram based on the influence of cultural, nutritional and physiological characters suggests moderate heterogeneity within the populations of A. alternata and A. tenuissima. The small-spore species formed five clusters that fundamentally paralleled the morphological groupings. However, the results provided no evidence for geographical and pathogenicity clustering of isolates

Simulator-based assessment of ankle arterial systolic blood pressure measurement skills

OBJECTIVE: Learning basic vascular examination is a complex process. Very few studies have focused on the ability to measure the arterial systolic blood pressure at the ankle (ASBPa). The aim of this study was to objectively assess the effects of a 1-h practical educational intervention on the ability to measure ASBPa among medical students. METHODS: A total of 27 medical students were prospectively recruited. Two evaluation sessions of ASBPa measurement skills were conducted, before (T1) and after a 1-h practical lesson (T2). To assess the learning effect associated to the simulator-based evaluation, a control group composed by nonmedical students, not involved in the practical lesson, was also tested. Objective assessments of ASBPa measurements were performed by an instrumented leg prototype. RESULTS: There was a nonsignificant decreasing trend measurement time after practical lesson. The average pressure determination error (ΔP) was significantly reduced: ΔPT1: 10.5 ± 13.8 mmHg vs. ΔPT2: 5.7 ± 6.0 mmHg (P = 0.002). The mean deflation rate (DR) of the cuff was significantly decreased: DRT1: 12.9 ± 9.2 mmHg/s vs. DRT2: 8.7 ± 4.6 mmHg/s (P = 0.001). The control group did not show significant changes. CONCLUSION: A 1-h practical learning could improve some parameters of the ASBPa measurement among medical students, but was not sufficient to allow the measured technical factors to reach established guidelines