Development of a screening method for resistance to Phytophthora cactorum

In The Netherlands the fungus Phytophthora cactorum, which causes crown rot in strawberry plants, has become a problem. Because of high losses of plants and the difficulty of chemical control, resistant cultivars are wanted. Therefore we wish to develop an efficient, reliable and fast screening method, which can be used for breeding and for determining the Value for Cultivation and Use (VCU) with regard to Plant Variety Rights. In previous research cultivars were screened by a "crown-test", which is destructive, inaccurate and very laborious. So a new method was developed using a hydroponic system (NFT). Runners of different cultivars were planted out in rockwool plugs, followed by artificial inoculation of the NFT system with a spore suspension of P. cactorum. The resistance level was determined by the period between infection and plant death. Large differences in resistance between cultivars were found. Susceptible cultivars started dying ten days after infection. Highly resistant cultivars were still apparently healthy after 90 days. Results corresponded well with earlier experiences. The test proved to be sufficiently accurate for testing cultivars

Development of a screening method for resistance to Phytophthora cactorum

In The Netherlands the fungus Phytophthora cactorum, which causes crown rot in strawberry plants, has become a problem. Because of high losses of plants and the difficulty of chemical control, resistant cultivars are wanted. Therefore we wish to develop an efficient, reliable and fast screening method, which can be used for breeding and for determining the Value for Cultivation and Use (VCU) with regard to Plant Variety Rights. In previous research cultivars were screened by a "crown-test", which is destructive, inaccurate and very laborious. So a new method was developed using a hydroponic system (NFT). Runners of different cultivars were planted out in rockwool plugs, followed by artificial inoculation of the NFT system with a spore suspension of P. cactorum. The resistance level was determined by the period between infection and plant death. Large differences in resistance between cultivars were found. Susceptible cultivars started dying ten days after infection. Highly resistant cultivars were still apparently healthy after 90 days. Results corresponded well with earlier experiences. The test proved to be sufficiently accurate for testing cultivars

Saccular Abdominal Aortic Aneurysms Patient Characteristics, Clinical Presentation, Treatment, and Outcomes in the Netherlands

Objective: The aim of this was to analyze differences between saccularshaped abdominal aortic aneurysms (SaAAAs) and fusiform abdominal aortic aneurysms (FuAAAs) regarding patient characteristics, treatment, and outcome, to advise a threshold for intervention for SaAAAs.Background: Based on the assumption that SaAAAs are more prone to rupture, guidelines suggest early elective treatment. However, little is known about the natural history of SaAAAs and the threshold for intervention is not substantiated.Methods: Observational study including primary repairs of degenerative AAAs in the Netherlands between 2016 and 2018 in which the shape was registered, registered in the Dutch Surgical Aneurysm Audit (DSAA). Patients were stratified by urgency of surgery; elective versus acute (symptomatic/ruptured). Patient characteristics, treatment, and outcome were compared between SaAAAs and FuAAAs.Results: A total of 7659 primary AAA-patients were included, 6.1% (n = 471) SaAAAs and 93.9% (n = 7188) FuAAAs. There were 5945 elective patients (6.5% SaAAA) and 1714 acute (4.8% SaAAA). Acute SaAAApatients were more often female (28.9% vs 17.2%, P = 0.007) compared with acute FuAAA-patients. SaAAAs had smaller diameters than FuAAAs, in elective (53.0mm vs 61 mm, P = 0.000) and acute (68mm vs 75 mm, P = 0.002) patients, even after adjusting for sex. In addition, 25.2% of acute SaAAA-patients presented with diameters <55mm and 8.4% <45 mm, versus 8.1% and 0.6% of acute FuAAA-patients (P = 0.000). Postoperative outcomes did not significantly differ between shapes in both elective and acute patients.Conclusions: SaAAAs become acute at smaller diameters than FuAAAs in DSAA patients. This study therefore supports the current idea that SaAAAs should be electively treated at smaller diameters than FuAAAs. The exact diameter threshold for elective treatment of SaAAAs is difficult to determine, but a diameter of 45mm seems to be an acceptable threshold.Vascular Surger