citrus is one of the most important fruit crops in iran. among the citriculture areas of iran, mazandaran province has the highest acreage (about 100,000 ha), production and number of varieties nationwide. unauthorized importation of citrus species and cultivars and propagation by growers and nurserymen have led to perpetuation and spread of virus, viroid and other graft-transmissible pathogens...

Seven commercial essential oils extracted from the plant species Boesenbergia rotunda (L.) Mansf., Citrus hystrix DC., Curcuma longa L., Litsea cubeba (Lour.) Pers., Piper nigrum L., Psidium guajava L. and Zingiber officinale Roscoe, and naphthalene as a control, were evaluated for repellent activity against the three cockroach species Periplaneta americana (L.), Blattella germanica (L.) and Ne...

BACKGROUND Citrus has an extended juvenile phase and trees can take 2-20 years to transition to the adult reproductive phase and produce fruit. For citrus variety development this substantially prolongs the time before adult traits, such as fruit yield and quality, can be evaluated. Methods to transform tissue from mature citrus trees would shorten the evaluation period via the direct productio...

Nucleotide sequences were determined for two hop stunt viroid-related Group II citrus viroids characterized as either a cachexia disease non-pathogenic variant (CVd-IIa) or a pathogenic variant (CVd-IIb). Sequence identity between the two variants of 95.6% indicated a conserved genome with the principal region of nucleotide difference clustered in the variable (V) domain. Full-length viroid RT-...

Viroids are small (246-401 nucleotides), single-stranded, circular RNA molecules that infect several crop plants and can cause diseases of economic importance. Citrus are the hosts in which the largest number of viroids have been identified. Citrus exocortis viroid (CEVd), the causal agent of citrus exocortis disease, induces considerable losses in citrus crops. Changes in the gene expression p...