Cultivar susceptibility and environmental parameters affecting symptom expression of red leaf blotch of almond in Spain

Plant Disease ◽  
2020 ◽  
Author(s):  
Xavier Miarnau ◽  
Lourdes Zazurca ◽  
Laura Torguet ◽  
Erick Zúñiga ◽  
Ignasi Batlle ◽  
...  

Red leaf blotch (RLB) of almond, caused by Polystigma amygdalinum, is an important foliar disease of this nut tree in the Mediterranean basin and Middle East regions. In recent years, the incidence of this disease has increased in Spain corresponding to increases in the area of newly-planted orchards and the use of susceptible cultivars. In 2009, an experimental orchard including 21 almond cultivars was planted at Les Borges Blanques, Lleida, NE Spain. No fungicide treatments were applied during the 10-year experimental period (2009-2018) in order to allow natural disease development. Cultivar susceptibility to RLB was assessed each year, from 2011 to 2018, through visual observations of symptoms in naturally-infected trees. The experimental results led us to classify the cultivars into five susceptibility groups. The most susceptible were 'Tarraco', 'Guara', 'Tuono', 'Marinada', 'Desmayo Largueta', and 'Soleta', whereas 'Mardía' was the most tolerant. The annual incidence of disease was positively correlated with accumulated rainfall in spring, and especially in April, while it was negatively correlated with high spring and summer temperatures, especially in May. These findings could be used to improve disease management strategies by identifying the most susceptible cultivars and improving the timing of fungicide application.

1996 ◽  
Vol 126 (2) ◽  
pp. 161-168 ◽  
Author(s):  
C. Porqueddu ◽  
A. Loi ◽  
P. S. Cocks

SUMMARYThe hardseededness and pattern of hard seed breakdown of 35 accessions of Medicago polymorpha, collected in Sardinia, were compared with Circle Valley, an Australian cultivar, near Sassari, northern Sardinia. The seed was produced in three consecutive years (1991–93), and the hardseededness measured at intervals in trie field during the summer following its production. The results were related to previously measured pod characteristics that separated the varieties polymorpha and vulgarisThe variety polymorpha, which had been collected mainly from coastal regions, was harder seeded than the variety vulgaris, which had been collected mainly from cooler, inland regions. Wherever the origin, hardseededness levels remained > 85% even in the year when seed softening was greatest (1992). In other years means of 94% (1991) and 97% (1993) of seed remained hard in late September. In 1992 and 1993 most hard seed breakdown occurred between early August and early September, while in 1991 hard seed breakdown occurred in September itself. There was little difference between varieties in the pattern of hard seed breakdown. Seedling emergence was related to the amount of seed that became soft during the previous summer. The results also confirmed that hard seeds soften sequentially from the proximal end of the pod (nearest the calyx) to the distal end.The Australian cultivar was one of the hardest seeded accessions, showing very little hard seed breakdown during the experimental period. This result highlights the importance of selecting pasture legumes under the conditions in which they are to be used: in Australia, cultivar Circle Valley usually loses some 20% of its hardseededness in the first year, comparable with the softest Sardinian accessions in Sardinia. Even among the Sardinian accessions, most were probably too hard seeded in 1993. Nevertheless it is likely that material in this experiment will be released as commercial cultivars for Sardinia and other similar environments in the Mediterranean basin.


2011 ◽  
Vol 103 (3-4) ◽  
pp. 335-346 ◽  
Author(s):  
Raffaele Pelorosso ◽  
Stefano Della Chiesa ◽  
Ulrike Tappeiner ◽  
Antonio Leone ◽  
Duccio Rocchini

2008 ◽  
Vol 95 (1-2) ◽  
pp. 91-109 ◽  
Author(s):  
H. Feidas ◽  
G. Kokolatos ◽  
A. Negri ◽  
M. Manyin ◽  
N. Chrysoulakis ◽  
...  

NeoBiota ◽  
2020 ◽  
Vol 59 ◽  
pp. 77-97 ◽  
Author(s):  
Michel Frem ◽  
Daniel Chapman ◽  
Vincenzo Fucilli ◽  
Elia Choueiri ◽  
Maroun El Moujabber ◽  
...  

After the recent high-impact European outbreaks of Xylella fastidiosa (Xf), a xylem-limited plant pathogenic bacterium native to the Americas, this research aims to rank the risks of potential entry, establishment and spread of Xf in new countries across Europe, the Middle East and North Africa. A novel risk-ranking technique is developed, based on combining entry risk drivers (imported plants, direct flights and ferry connections) with risk factors related to establishment and spread (presence of potential insect vectors, vulnerable economic crops, alternative hosts and climate suitability) of this pathogen. This reveals that western European countries have the highest risk for entry, but that the Mediterranean basin runs the highest risk for establishment and spread of Xf. Lebanon in particular has the highest level of risk for Xf dispersal within its suitable territory. Countries without current outbreaks combining high risks of Xf arrival and establishment are mainly in the Mediterranean basin: Turkey is at the highest level of risk, followed by Greece, Morocco and Tunisia, which are ranked at the high level. The ranking model also confirms the vulnerability, in terms of invasion by Xf, of southern European countries (Italy, Portugal and Spain) in which the pathogen has already been reported. High summer temperatures in these southern countries are likely to be the significant determinant for the overall invasion process, while northern European countries have a high level risk for the arrival of the pathogen, but relatively low summer temperatures may limit establishment and spread of major outbreaks. In general, our study provides a useful approach for mapping and comparing risks of invasive non-native species and emerging pathogens between countries, which could be useful for regional horizon scanning and phytosanitary and biosecurity management.


Author(s):  
Joshua M. White

This book offers a comprehensive examination of the shape and impact of piracy in the eastern half of the Mediterranean and the Ottoman Empire’s administrative, legal, and diplomatic response. In the late sixteenth and seventeenth centuries, piracy had a tremendous effect on the formation of international law, the conduct of diplomacy, the articulation of Ottoman imperial and Islamic law, and their application in Ottoman courts. Piracy and Law draws on research in archives and libraries in Istanbul, Venice, Crete, London, and Paris to bring the Ottoman state and Ottoman victims into the story for the first time. It explains why piracy exploded after the 1570s and why the Ottoman state was largely unable to marshal an effective military solution even as it responded dynamically in the spheres of law and diplomacy. By focusing on the Ottoman victims, jurists, and officials who had to contend most with the consequences of piracy, Piracy and Law reveals a broader range of piratical practitioners than the Muslim and Catholic corsairs who have typically been the focus of study and considers their consequences for the Ottoman state and those who traveled through Ottoman waters. This book argues that what made the eastern half of the Mediterranean basin the Ottoman Mediterranean, more than sovereignty or naval supremacy—which was ephemeral—was that it was a legal space. The challenge of piracy helped to define its contours.


Author(s):  
Matthew D. C. Larsen

The concept of textual unfinishedness played a role in a wide variety of cultures and contexts across the Mediterranean basin in antiquity and late antiquity. Chapter 2 documents examples of Greek, Roman, and Jewish writers reflecting explicitly in their own words about unfinished texts. Many writers claimed to have written unfinished texts on purpose for specific cultural reasons, while others claimed to have written texts that slipped out of their hands somehow with their permission.


Author(s):  
Madadh Richey

The alphabet employed by the Phoenicians was the inheritor of a long tradition of alphabetic writing and was itself adapted for use throughout the Mediterranean basin by numerous populations speaking many languages. The present contribution traces the origins of the alphabet in Sinai and the Levant before discussing different alphabetic standardizations in Ugarit and Phoenician Tyre. The complex adaptation of the latter for representation of the Greek language is described in detail, then some brief attention is given to likely—Etruscan and other Italic alphabets—and possible (Iberian and Berber) descendants of the Phoenician alphabet. Finally, it is stressed that current research does not view the Phoenician and other alphabets as inherently simpler, more easily learned, or more democratic than other writing systems. The Phoenician alphabet remains, nevertheless, an impressive technological development worthy, especially by virtue of its generative power, of detailed study ranging from paleographic and orthographic specifications to social and political contextualization.


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