abstract in october 2009, in one of the alstroemeria (alatroemeria sp.) greenhouses, located in khorasan razavi province, tospovirus-like symptoms (necrosis) were observed on stems, petioles, flowers and leaves of some plants. sap extracts from these plants were mechanically inoculated to indicator plants. necrotic local lesions were observed on petunia hybrida and chenopodium quinoa. necrotic ...

Hsu, C. L., Hoepting, C. A., Fuchs, M., Smith, E. A., and Nault, B. A. 2011. Sources of Iris yellow spot virus in New York. Plant Dis. 95:735-743. Iris yellow spot virus (IYSV) has been found consistently in commercial dry bulb onion fields throughout New York State since 2006. Yearly recurrence of IYSV may result from annual reintroductions of the virus or persistence of the virus in overwinte...

Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), a worldwide pest of onion, Allium cepa L., can reduce onion yield by > 50% and be even more problematic when it transmits Iris yellow spot virus (family Bunyaviridae, genus Tospovirus, IYSV). Because T. tabaci is difficult to control with insecticides and other strategies, field studies on onion, Allium cepa L., resistance to T. ta...

Thrips-transmitted Iris yellow spot virus is an economically important viral pathogen of Allium crops worldwide. A global analysis of known IYSV nucleocapsid gene (N gene) sequences was carried out to determine the comparative population structure, spatial and temporal dynamics with reference to its genetic diversity and evolution. A total of 98 complete N gene sequences (including 8 sequences ...

BACKGROUND New viruses pathogenic to plants continue to emerge due to mutation, recombination, or reassortment among genomic segments among individual viruses. Tospoviruses cause significant economic damage to a wide range of crops in many parts of the world. The genetic or molecular basis of the continued emergence of new tospoviruses and new hosts is not well understood though it is generally...

Onion thrips, Thrips tabaci Lindeman, is a worldwide pest of onion whose feeding damage and transmission of Iris yellow spot virus (IYSV) may reduce onion yields. Little is known about the seasonal dynamics of T. tabaci dispersal, the distance of dispersal, or the movement of thrips infected with IYSV during the onion-growing season. To address these questions, T. tabaci adults were collected u...

During the past two decades, onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), has become a global pest of increasing concern in commercial onion (Allium cepa L.), because of its development of resistance to insecticides, ability to transmit plant pathogens, and frequency of producing more generations at high temperatures. T. tabaci feeds directly on leaves, causing blotches and p...

Iris yellow spot (IYS) disease in onion (Allium cepa L.) is caused by thrips (Thrips tabaci vectored virus (IYSV). The absence of cultivars that are resistant/tolerant to and/or IYS a challenge for bulb and seed production worldwide. To measure selection progress reduced/delayed symptom expression breeding lines after two cycles, selections were performed 2011 on previously evaluated exhibited ...