Factors Affecting Infection and Disease Development on Olive Leaves

Factors Affecting Infection and Disease Development on Olive Leaves

José R. Viruega, Luis F. Roca, Juan Moral, and Antonio Trapero | View Article Infection and development of olive scab disease, caused by Fusicladium oleagineum, were evaluated on detached leaves and potted plants of the susceptible cultivar Picual in growth chambers and a shadehouse. An inoculum dose of 1 × 105 conidia per ml was selected from a range of densities tested, and it was used for all experiments. Infection occurred from 5 to 25°C, and disease severity was the greatest at ~20°C for wetness durations of 12 to 24 h and at ~15°C for longer durations. Based on a generalized form of the Analytis Beta model, the optimum temperature and minimum wetness duration for infection were 15.5°C and 11.9 h. Dry periods ≤78 h immediately after inoculation did not reduce disease incidence but did reduce disease...
Evaluation of the Incidence and Severity of Olive Leaf Spot

Evaluation of the Incidence and Severity of Olive Leaf Spot

Mazen Salman, Abd-Almonem Hawamda, Ahmad Al-Ashqar Amarni, Mahmoud Rahil, Hajaj Hajjeh, Basel Natsheh, Ruba Abuamsha | View Article Olive Leaf Spot (OLS) is found in many parts of the world and cause readuced growth and yield in olive trees. In this study, investigations were carried out to measure the incidence (% infected leaves) and severity (number of lesions/leaf) of OLS in olive growing regions in Palestine, including the regions of Hebron, Bethlehem, Tulkarm, Salfit, Jenin, Nablus, Ramallah and Qalqilyah. OLS was found in all study areas with significantly higher percent incidences in Jenin and Nablus (67.16% ± 18.16% and 46.06% ± 23.70%, respectively). OLS was more severe in Nablus, Qalqilyah, Jenin and Tulkarm (severity grade 3.0 – 3.7). Analysis indicate that there is a positive correlation (R2 = 0.597) between dis-ease incidence and severity. OLS appeared to be particularly severe on trees that were growing in regions with higher annual rainfall. The correlation between severity and rainfall was positive (R2 =...
Plant sanitation

Plant sanitation

Vera Sergeeva | View Article A number of growers have queried how disease spreads to isolated groves, and asked for advice on establishing a new olive grove with fewer pests and disease problems into the future. This article provides some general rules and practices to prevent the introduction and/or spreading of pests and...
Disease resistance and adaptability of olive cultivars

Disease resistance and adaptability of olive cultivars

Vera Sergeeva | View Article Olives are extensively cultivated in the world and the industry continues to expand in many countries. Approximately 11 million hectares are under olive cultivation, comprising an estimated 600 varieties. New types of olive trees have been created over the years, both by adaptation to different climates and multiplication methods. Climate is the most important limiting factor in the distribution of olives, as temperature controls growth, reproduction and development of diseases and pests. Environmental factors also play an important role in managing diseases and...
Factors Affecting Infection and Disease Development on Olive Leaves Inoculated with Fusicladium oleagineum

Factors Affecting Infection and Disease Development on Olive Leaves Inoculated with Fusicladium oleagineum

José R. Viruega, Luis F. Roca, Juan Moral, and Antonio Trapero | View Article Infection and development of olive scab disease, caused by Fusicladium oleagineum, were evaluated on detached leaves and potted plants of the susceptible cultivar Picual in growth chambers and a shadehouse. An inoculum dose of 1 × 105 conidia per ml was selected from a range of densities tested, and it was used for all experiments. Infection occurred from 5 to 25°C, and disease severity was the greatest at ~20°C for wetness durations of 12 to 24 h and at ~15°C for longer durations. Based on a generalized form of the Analytis Beta model, the optimum temperature and minimum wetness duration for infection were 15.5°C and 11.9 h. Dry periods ≤78 h immediately after inoculation did not reduce disease incidence but did reduce disease...