Population Dynamics of the Root-knot Nematodes Meloidogyne incognita (Kofoid & White) Chitwood and M. javanica (Treub) Chitwood on Grapevines in two different Regions of South Africa

Two root-knot nematode species, Me/oidogyne incognita and M.javanica, were studied with regard to their seasonal population fluctuations on grapevines growing in two vastly different climatic areas. Regular observations on reproduction and numbers of larvae in the soil were compared with patterns of root growth, soil temperature and moisture. Population fluctuations of the two species showed similar trends in spite of the climatic differences in the two areas, but M. incognita in the northern Cape reached higher populations. Larvae populations in the soil declined in summer in both areas and increased during autumn to reach peaks in winter. With the onset of root growth in spring, larvae numbers decreased in the soil, as a result of large scale root penetration

New and little known Laimydorinae species from Fynbos in the south-western Cape (Nematoda: Dorylaimidae)

Calcaridorylaimus sirgeli n.sp. is described from Cape Fynbos in mountains in the south-western Cape Province. It differs from all known species in the genus by the presence of advulval ornamentation, and is compared in detail with Calcaridorylaimus signatus (Loot, 1975) and Calcaridorylaimus ruwenzorii (De Coninck, 1935). A single specimen of Drepanodoryiaimus williamsi (Heyns & Kruger, 1983) is compared with specimens from the Transvaal and Mauritius. Mesodorylaimus sp. cf. graciosus Andràssy, 1986 is reported from South Africa for the first time

Strategies for Chemical Control of Root-knot Nematodes (Meloidogyne spp.) in Established Vineyards

Grape-vine root growth was measured for vertical and horizontal distribution as well as seasonal growth periods. The persistance of aldicarb and fenamiphos in the soil as well as in leaves and fruit of grape-vines was monitored over a prolonged period to establish behaviour patterns which inflnence chemical control strategies. Most roots occurred within 600 mm from the trunk, both vertically and horizontally. Two periods of root development occurred annually. Accordingly applications of nematicides should be made in a band covering 600 mm on both sides of the vine trunk, either after harvest and/or during budburst. Results on residues of aldicarb and fenamiphos stress the importance of adequate water supply after application. Both nematicides will reach the bulk of the roots if correctly placed and were still detected after 42 days and 70 days respectively. Applications during spring with aldicarb and fenamiphos at the dosages used will have no effect on the fermentation of grape musts nor result in toxic residues exceeding 0,05 mg/kg in the grapes

The influence of anatomy app use on chiropractic students’ learning outcomes: a randomised controlled trial

Background: Anatomy apps supplement traditional learning; however, it is unknown if their use can improve students' outcome. The present study examined whether the use of anatomy apps improved student performance on a neuroanatomy assessment. Methods: Second-year anatomy students, enrolled in a Bachelor of Science with Chiropractic Major program, were randomly allocated to experimental and control groups in July 2015. Students completed the Self-Directed Learning Readiness Scale (SDLRS). The experimental group had access to iPads with four anatomy apps for three weekly classes (1.5 h each). One week after the last class, students were assessed by an online 30-question neuroanatomy test. Linear regression was used to examine the association between test scores and app use, gender, previous anatomy unit score and SDLRS scores. Students' views on apps were collected by focus group discussion immediately after the test. Results: Completed questionnaires were obtained from n = 25 control and n = 25 experimental students. There was no association between app use and neuroanatomy assessment score (B = 1.75, 95 % CI: -0.340-3.840, p = 0.099). Only previous anatomy unit score (B = 0.348, 95 % CI: 0.214-0.483, p < 0.001) affected neuroanatomy assessment scores. Students favored apps with clinical images and features including identification pins, sliding bars and rotatable 3D images. Conclusions: App use did not enhance learning outcomes in a second-year anatomy unit

Resistance of Grapevine Rootstocks to Meloidogyne incognita under Field Conditions

Resistance of grapevine rootstocks to root-knot nematodes (Meloidogyne incognita) was studied in field trials. Resistance was found to be adequately expressed by the degree of galling. A highly significant positive correlation exists between nematode populations in the soil as well as nematode reproduction and galling, while grapevine growth and yield were negatively related to the degree of infestation. However, information regarding rootstock tolerance and intolerance (sensitivity) was not considered reliable. It was further shown that a susceptible scion would not lower the resistance of the rootstock involved. Based on their rate of galling, rootstocks Ramsey, 99 Richter PS, Dogridge, Freedom, Harmony and 101-14 Mgt are resistant while Jacquez, 140 Ruggeri, Grezot-1, Maleque 44-53 and Constantia Metallica are susceptible

Comparative antibacterial activity of two Helichrysum species used in male circumcision in South Africa.

The leaves of Helichrysum pedunculatum and H. longifolium are used for the treatment of wounds arising from male circumcision by the Xhosas and the Pondos of South Africa, respectively. The antibacterial activity of these herbs was compared by direct bioautography using Staphylococcus aureus. Extracts from the leaves of H. pedunculatum showed more activity against the bacterium than those from H. longifolium. Heating the extracts from the latter, further reduced their activity against S. aureus, The traditonal heating of the leaves of this plant over hot ash before use is, therefore, likely to reduce their activity against infection

Immunology knowledge as one of the basic sciences that forms the foundations to developing sound clinicians

Objective: The aim of this study was to (1) generate a valid questionnaire to determine immunology knowledge, (2) compare immunology knowledge across 3 different cohorts of chiropractic students that had already studied immunology, (3) examine the attitudes of chiropractic students to the study of immunology, and (4) examine whether students' attitudes affected their knowledge levels. Methods: Factor analysis was used to refine an immunology knowledge and perceptions questionnaire that was generated by a group of experts that was then completed by 90 students. Immunology knowledge level of each of the cohorts was compared using a 1-way analysis of variance. Kappa statistics were used to measure agreement between 2 statements, and logistic regression was used to determine whether students' attitudes were associated with their knowledge levels. Results: There was a significant difference in the immunology knowledge levels across the 3 year groups (F[2, 87] = 4.78, p = .011). Fifth-year students (n = 26) demonstrated 25% less immunology knowledge than third-year students (n = 35; p = .005). Of 90 students, 64 agreed that immunology knowledge was important to chiropractors, and 53 agreed that immunology knowledge was important for the average person. No relationship existed between their value of immunology knowledge and their score on the multiple-choice questions. Conclusion: Third-year students' immunology knowledge was significantly higher than that of the fifth-year students. Students value immunology knowledge, but this does not translate to retention of this knowledge. The validated questionnaire is a useful tool for assessing immunology knowledge retention for undergraduate students

The Occurrence and Infectivity of Arbuscular Mycorrhizal Fungi in Inoculated and Uninoculated Rhizosphere Soils of Two-year-old Commercial Grapevines

Arbuscular mycorrhizal (AM) fungal populations present in the rhizosphere of vine roots in the vineyards of a commercial farm in the Stellenbosch Region were investigated using microscopic analyses. AM root colonisation levels of between 70% and 90% were found in both grapevine roots that were previously artificially inoculated with commercial AM inocula, and in uninoculated (control) grapevine roots. The AM fungal isolates in the rhizosphere soil, identified using morphological criteria, belonged to the genera Acaulospora, Gigaspora, Glomus, Sclerocystis and Scutellospora.  The majority of species found was not present in the commercial inocula and was either indigenous to the vineyard or originated from the nursery where the vines were obtained. Isolates of Glomus and Acaulospora appeared to be the most abundant. The AM fungal species occurred at a soil phosphorus (P) concentration of up to 80 mg/kg P and a soil pH (KCl) that ranged between 5.63 and 6.10. Total spore counts ranged between 1 000 and 3 779 spores/100 g dry soil. In accordance with literature, lower spore concentrations were recorded for the heavier soil types with no cover crop system, compared with the sandy soil type on which cover crops were sown annually