بررسی آرایه شناختی برخی از گونه‌های ایرانی سرده گل فراموشم مکن از تیره گاو زبانیان بر اساس صفات ریز ریخت‌شناسی کاسه گل و فندقه

گیاهان سرده گل فراموشم مکن با داشتن فندقه های تخم مرغی، صاف و براق قهوه ای تا سیاه خود  از سایر سرده های تیره گاوزبانیان قابل تشخیص هستند. بررسی روابط آرایه شناختی گونه های این سرده به علّت ارزش زینتی و صنعتی و دارا بودن اسانس های معطر، مهم است. پژوهش حاضر با هدف بررسی آرایه شناسی گیاهان سرده گل فراموشم به کمک صفات ریخت شناسی کاسه و فندقه انجام شده است. نمونه های خشک هرباریومی از هرباریوم های دانشگاه خوارزمی تهیه شدند، کاسه گل و فندقه ها در زیر استریومیکروسکوپ جدا و تصاویر آنها تهیه شد و سپس تصاویر توسط نرم افزارهای سنجش و اندازه گیری تصاویر و تحلیل داده ها، از جمله imagej 1/5v و past 4/13v بررسی شدند. نتایج نشان دادند صفات کاسه، کرک های کاسه گل و صفات فندقه نظیر شکل دندانه کاسه گل، شکل پراکندگی کرک ها و همچنین وجود یا عدم و جود زائده سفید در فندقه ها در افتراق گونه های این سرده مفید هستند. با بررسی آرایه شناسی و تبارشناختی صفات کاسه و کرک های کاسه گل و فندقه مشخص شد این صفات می توانند تا حدودی جهت جداسازی زیر سرده m. pop. (turcz.)  strophiostoma در این سرده نیز مفید باشند. همچنین نتایج حاصل از تحلیل درخت تبارشناختی بر اساس صفات کاسه گل و فندقه ها نشان دادند گونه های این زیر سرده تا حدودی تک نیا هستند. در این پژوهش بر اساس صفات تشخیصی فندقه و کاسه کلید شناسایی برای گونه های مورد بررسی ارائه شده است.

taxonomic investigation of some iranian myosotis l. species (boraginaceae), by using the calyx and nut traits

the genus myosotis (forget-me-not) is distinct by having ovoid, smooth, and shiny nuts with brown to black color from the other related taxa in the boraginaceae family. this study aimed to investigate taxonomic and phylogenic relations in some iranian myosotis species based on calyx and nut characters. in this way, dry herbarium specimens were used from t and far herbaria at kharazmi university. their sepals and achenes were separated under a stereomicroscope, their images were prepared by a digital camera and then were prepared and analyzed using imagej 1.5v and past 4.13v software. it was found that calyx and calyx trichome and nut characteristics such as the shape of the calyx, the shape of the trichome distribution, and the presence of ligulate white appendage in the nut, prove their usefulness in differentiating the species of the genus myosotis. the phylogenetic study of calyx and calyx trichome characteristics and nut characteristics can be used to separate the subgenus strophiostoma m.pop. (turcz.) from other members of the genus as a monophyletic taxon. in this article, an identification key for the studied species is presented based on the diagnostic traits of the nut and the calyx. introductionthe genus forget-me-not flower (myosotis l.) includes 80 to 100 species in the world (mabberley, 2008; weigend et al., 2016), and up until now, 18 species of which were reported from iran (akbarnejad, 2023). this genus is considered as a monophyletic taxon (shrafati et al., 2014) and could be separated from other genera of the family boraginaceae by having ovoid, smooth, and shiny nuts with brown to black color (winkworth et al., 2002). although myosotis could be clearly defined by morphological characteristics, the genus is considered as taxonomically complex (al-shehbaz, 1991). so far, numerous research projects have been executed on the morphological, micro-morphological and molecular traits of flowering plants, including family boraginaceae and genus myosotis, in the world (akbarnejad, 2023; noroozi et al., 2022; akbarnejad et al., in press; abbasi et al., 2011; díez, 1994; metcalfe and chalk, 1979; meudt, 2015; ning et al., 1992; nyawuame and gill, 1990; cohen, 2014; retief and van wyk, 1997; zamani, 2022; dylami et al., 2018; javanmardi, 2015,  et cetera) that aimed to determine their proper taxonomic classification. therefore, the current research was carried out to investigate the phylogenetic relationships among the species of the genus myosotis, and since the myosotis genus has beautiful and fragrant flowers, the exact taxonomic identification of its species may help to breed and reproduce species with ornamental importance and valuable in perfumery industry (see znajdek-awiżeń et al., 2014). material and methodsthe samples were collected from the t and far herbaria of kharazmi university, their sepals and nuts were separated under a stereomicroscope, and their images were prepared by a digital camera.  then, the studied traits were measured and coded using imagej 1.5v software, and by past 13.4v software, a phylogenetic tree was reconstructed by upgma method (unweighted pair group method with arithmetic mean). results and discussionthe trichome length was found to be long in m. scorpioides l., m. olympica boiss., m. asiatica (vestergr.) schischk. & serg., m. alpestris f.w. schmidt., m. sylvatica hoffm., m. lithospermifolia (willd.) hornem. and m. pseudopropinqua popov; whereas the trichome length in species m. ramosissima rochel ex. schultes., m. stricta link ex roem. & schult., m. anomala riedl., m. sparsiflora j.c. mikan ex pohl. and m. propinqua fisch. & c.a.mey were found to be relatively short. the largest and smallest length and width of the calyx were related to m. sylvatica and m. sparsiflor, respectively. the inadequate number of variations observed in the calyx and calyx trichome traits was not found to be suitable for the identification of subgeneric taxa in the specific rank but could be useful in the study of taxonomic relationships among the higher taxonomic ranks. calyx, calyx trichome, and nut traits could be applied in the study of taxonomic relationships among the species of myosotis, as well as to investigate the relationship among and within subgenra of myosotis, e.g., subgenus strophiostoma m. pop. (turcz.), as the species of this subgenus were found to form the monophyletic subgenus by the criteria applied in the present study. the percentage changes in nut traits were found to be compatible with those in flower and flower trichome traits, in contrast to the previous findings about pollen and stem traits (akbarnejad et al. in press; akbarnejad, 2023). conclusionthe percentage of changes in the morphological traits studied in genus myosotis was above 60% in nut traits and below 60% in calyx and calyx trichome traits. calyx and calyx trichome characteristics as well as nut characteristics were found to be useful for the separation of taxa above the specific rank, e.g., the separation of the subgenus strophiostoma, as the species of this subgenus were shown to form a monophyletic group by examining the nut, calyx and calyx hair characteristics in the present research.