The quality of the host plant affects the life-history traits of plant-feeding arthropods. The effect of several soybean cultivars on the fitness of Tetranychus urticae was assayed by determining developmental time and fertility life-table parameters for mites on leaf discs at 25 ± 1°C, 70 ± 10% relative humidity and 16 : 8 light : dark photoperiod. Immature developmental time was significantly longer on LWK and Gorgan 3 than on the other cultivars, whereas total fecundity per female was higher on Gorgan 3 than the other cultivars. There were significant differences among the forms of the survival curves of mites on the cultivars. Statistical comparisons of the jackknifed intrinsic rate of natural increase, generation time, doubling time, and finite rate of increase, suggest unsuitability of the cultivars LWK and Gorgan 3 as hosts for the development of two-spotted spider mite. No significant difference was observed for the net reproductive rates among the cultivars. The lower population rate of the mite could be the result of antibiotic resistance in the cultivars LWK and Gorgan 3.
Urtica dioica L. is an Iranian native pharmacological plant for which little attention has been paid to the anatomical structure. Medical applications of this plant include diabetes therapy, digestive improvement, anemia and kidney disease therapy. Because climatic conditions can affect the anatomical structure which in turn affects pharmacological compositions, research on the anatomy of this plant is needed. In this research, plant samples were collected from populations near the cities of Brojerd, Mashad, Ghazvin, and Ramsar. Cross sections, were made from stem, leaf, and petiole at the second internodes, and stained using double staining methods. Differences between stem, leaf, and petiole tissues confirmed that climatic factors produced differences among the populations in anatomical structure of aerial organs. Noted differences included: 1-Number and diameter of vascular bundles with five vascular bundles in Ghazvin population, five to seven vascular bundles in the Brojerd population, and four vascular bundles in populations in Mashad and Ramsar. The Mashad and Ramsar populations differed in diameter. 2-Protective tissue and thickness of the cuticle of plants from Ghazvin had more tissues because of lower thermal mean and mountain region. 3-Differences in petiole diameter with the largest petiole diameter in the Mashad population and the smallest petiole diameter in the Ramsar population. These observed differences in anatomy confirmed the effect of climate on differentiation in anatomical structure in Urtica dioica L.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.