جستجوی مقالات مرتبط با کلیدواژه « مازندران » در نشریات گروه « بیوتکنولوژی و ژنتیک گیاهی »

Having knowledge of the combination and abundance of green algae leads to the formation of a clear image for measuring or commenting on food conditions in the lake and possible assessment or optimal use of water resources. This research was carried out to identify the ecological characteristics of the population of green algae and to compare their species diversity and distribution. Sampling of green algae was done during summer by Rottner 500cc. Three meters away from the pool side, 500 cc of the pool water was taken from four points byRuthender. The samples were poured into a bottle and fixed by 4% using formalin. Then, they were identified and counted in laboratory after sedimentation. A total of 23 species of green algae were identified in the waters of the studied pools, which comprised 22% of the total observed planktons. Crucigeniatetrapedi and Schroederiasetigera are the most prevalent species of green algae in terms of variety and density. According to the results, changes in variation were different. This study shows that green algae have a relatively high population in these aquatic ecosystems, and better understanding of the green algae in the warm fish ecosystem can lead to the development of a more consolidated picture of the ecological relationships and a better determination of the species that are useful in the farming of warm fish.

Hymenochaetaceae are wood inhabiting and causes of white rot. They are recognizable by drown Basidiocarp, Seta and no Cystidia in Hymenium. This study carried out in area about 7290.1 hectares of Neka forest area by forest surveying method. 8 species of fungi belong to family of Hymenochaetaceae have been colleted on 5 hosts; consist of one ectomycorrhizae, 4 saprophytes and 3 parasite. A review on previous reports showed that Coltricia perennis is new for Iranian mycoflora. In respect of fungi host associations for Iran 2 species are new.

Ants (Hymenoptera: Formicidae) are one of the important predators in different agroecosystems. Considering the importance of ants in predating and feeding at different life stages of pests, fauna and population fluctuation of these beneficial insects were studied in rice fields of Mazandaran province. Of the faunistic survey, totally 15 species of ants were collected and identified from the paddy fields in Mazandaran province. The results of population fluctuations on the stubbles of three varieties including, Fajr, Khazar and Nemat indicated that the ant's population density was higher on Fajr than the two other varieties, and there was not a significant difference between Khazar and Nemat. Samplings from 11 September to 15 November 2005 indicated that the population density increased until last October and then decreased gradually; the highest density was obtained in 30 October. The means comparison revealed the significant reciprocal effect of "sampling date × rice variety" on population density of ants "P<0.01".

The exact identification of key pests and their host plants in a region has very important role for their successful control. Fauna of stem borers, Chilo Zincken, 87 (Lepidoptera: Pyralidae) and their host plants were studied in Mazandaran province. Totally, four species including, C. partellus Swinhoe, C. phragmitellus Hubner, C. suppressalis Walker and C. sacchariphagus indicus (Kapur) were identified that among the mentioned species, C. sacchariphagus indicus is newly recorded for Iranian fauna. In a total of 7 host plants from 7 families including, Amarantaceae, Compositae, Cruciferae, Cyperaceae, Poaceae, Sparganiaceae and Typhaceae were identified as overwintering plant hosts of Chilo suppressalis larvae, a key pest of rice in northern Iran. From the collected host plants, two species including, Raphanus raphanistram and Eleusine indica are newly recorded from Iran as the host plants of C. suppressalis. The samplings indicated that the highest numbers of collected host plants were belong to the family Poaceae. Also, the results revealed that the larvae of C. suppressalis preferred three host plants of Xanthium pensylvanicum, Amaranthus spp. and Sorghum halopensae for overwintering.

The Pentatomidae (Heteroptera) are the important agricultural pests that cause sever damage to the crops. Regarading the pentatomid's importance as the key pests, and un-lack of knowledge of these insects in Central and Eastern Mazandaran, several samplings were conducted in different regions through 2003-2006. this research, 44 species of 28 genera were collected and determined as the fauna of Central and Eastern Mazandaran. Totally, over than 60 host plants especially pasturage plants and weeds were identified for the pentatomids of this study. Also, the dominant species of different parasitoids and predators of this region were collected and identified as the powerful and efficient natural enemies of the pests.