Seed Transmission of Verticillum dahlia in Olive as Detected by a Highly Sensitive Nested PCR-Based Assay

To determine whether the spread of Verticillium dahliae to new olive growing areas can be seed-borne, fruit samples of V. dahliae-infected symptomatic and asymptomatic trees of two olive cultivars (Shimlali and Nabali) were randomly collected in November and December 2003 from two olive-growing areas in Jordan. Seeds were excised from the fruits and some of the seeds were sown to produce progeny seedlings. Both seeds and the seedlings were tested for V. dahliae infection using standard plating and a nested polymerase chain reaction (PCR)-based assay that used primers from the internal transcribed spacer (ITS) regions of nuclear ribosomal RNA (rRNA) genes. The sensitivity of the nested PCR-based assay was investigated by amplifying the crude DNA of conidia. The incidence of V. dahliae infection in seeds and seedlings was significantly higher with the nested PCR-based assay than with the plating procedure in both symptomatic and asymptomatic trees of both olive cultivars. Infection rates were significantly higher in symptomatic than in asymptomatic trees and, in general, higher for the cv. Shimlali than the cv. Nabali. The incidence of V. dahliae infection in the seedlings was significantly higher than that in the seeds. The expected DNA fragments were amplified from all the concentrations of V. dahliae conidial suspensions used (2 104; 2 103; 2 102; 20 and 2 conidia µl-1) indicating that the assay was highly sensitive. Olive seeds of the two cultivars transmitted V. dahliae to the progeny seedlings in different percentages up to a maximum of 35%. Infected olive seed contributes significantly to pathogen dissemination

Designing and Implementing an Effective Courseware for the Enhancement of e-Learning

The objective of this study is to determine the effect of applying the cognitive theory of multimedia learning in an e-learning environment. Three versions of a course on how to master skills in Adobe Photoshop were designed and given to a sample of (60) students to test their effectiveness. This research sample was divided into three groups. The first was an experimental group that studied the subject through Course Facilitated Multimedia Principles (CFMP), like the multimedia principle, the modality principle and the contiguity principle. The second experimental group studied the subject through Course Not-Facilitated Multimedia Principles (CNFMP), which did not apply the multimedia principle. The last group is a control group that studied the subject through traditional methods. Learning outcomes were determined by achievement test. Differences between pre and post-test scores were analyzed. The results show that the students in the first experimental group had improved their academic achievement by 53.70%, while the students in the second experimental group improved by 45.80%. Finally, the students in the control group had improved their achievement only by 30.5%. The findings affirm that CFMP has more effect on student achievement than the traditional way or the CNFMP. This is an indication that the application of the multimedia principles has improved the students' ability to comprehend, and achieved higher levels in learning. We recommend that educators should continuously examine the effectiveness of their pedagogical strategies and smartly apply technologies to enhance student's learning

Survey of educational cyber ranges

This paper gauges the experience of educational institutions currently utilizing a Cyber Range. A Cyber Range is implemented to provide hands-on training in the cyber security field. This hands-on training produces a more skilled worker that is better equipped to enter the Cyber Security industry. A survey was conducted to provide a better knowledge of the uses, benefits, costs, and methods used to implement a Cyber Range at an educational institution