Four new species of Acanthobothrium van Beneden, 1850 are described from guitarfish, Rhynchobatus cf. djiddensis (Forsskål), collected from the Gulf of Oman and Persian Gulf. Acanthobothrium janineae sp. n., a category 1 species, differs from all congeners in category 1 by having a long vagina extending into the vas deferens and different, proglottid and testis number except Acanthobothrium hypermekkolpos Fyler et Caira, 2010. Acanthobothrium fylerae sp. n., a category 1 species, can be differentiated by a combination of characters including the total length, proglottid and testis number, cirrus sac shape, and the length of the vagina and ovarian lobes. Both new species are similar to A. hypermekkolpos reported from Rhynchobatus laevis (Bloch et Schneider) from Australia in their scolex proper length, hook size and muscular pad, respectively. Acanthobothrium asrinae sp. n., a category 1 species, differs from other category 1 species by the shape of its hooks and the position of the tubercle at the mid-length of the axial prongs; in this respect it resembles A. bartonae Campbell et Beveridge, 2002 reported from Australia. Acanthobothrium jamesi sp. n. is among six category 1 species with post-ovarian testes. It differs from these species by total length, proglottid and testis number and the extension of the ovarian lobes. Although it is thought that R. djiddensis occurs in the region, the identities of the hosts of the newly described Acanthobothrium species await verification. There are two forms of host in the region and were designated as R. cf. djiddensis 1 and R. cf. djiddensis 2. More taxonomic work and the use of molecular techniques are needed to resolve the true identity of the host species., Loghman Maleki, Masoumeh Malek, Harry W. Palm., and Obsahuje bibliografii
We studied water relations and gas exchange in six almond genotypes grafted on GF677 in response to withholding irrigation for 14 days and a subsequent 10-day rehydration period. The responses to drought stress significantly differed in the almond genotypes; the tolerant plants were distinguished and monitored. Leaf relative water content (RWC) decreased by more than 23%, leaf water potential dropped to less than -4.3 MPa, and electrolyte leakage increased to 43% in dehydration-sensitive genotypes. Photosynthesis (PN) and stomatal conductance (gs) of drought-sensitive genotypes were significantly reduced by 70% and 97% in response to water deficiency. Water stress significantly enhanced wateruse efficiency up to 10 folds in drought-tolerant almonds. The difference between leaf temperature and its surrounding air temperature (ΔT) increased significantly to more than 187% under water stress in drought-tolerant genotypes. In addition, the reduction in the g s and further ability to preserve RWC were involved probably in drought-tolerance mechanism in almond. Negative significant correlations were found between ΔT, PN, and gs. Based on the correlations, we suggested that ΔT could be used as a simple measurement for monitoring water stress development in the irrigation management of almond orchards. In conclusion, ‘Supernova’ and the Iranian genotypes ‘6-8’ and ‘B-124’, were found to be more droughttolerant compared with other genotypes in this experiment., S. Karimi, A. Yadollahi, K. Arzani, A. Imani, M. Aghaalikhani., and Obsahuje bibliografii