selection of an appropriate model is important for quantifying response of germination rate to temperature and determination of cardinal temperatures. this study was done to evaluate different nonlinear regression models to describe response of germination rate to temperature in medicinal pumpkin, borago and black cumin. the regression models were dent-like, segmented, beta, curvilinear, quadra...

predicting seed viability would be extremely beneficial to seed producers and the prediction of seed viability depends on understanding the quantitative relationships between seed longevity, seed moisture content and storage temperature. thus, the objective of this investigation was to quantify relationship between temperatures, seed moisture and seed deterioration and determination seed viabil...

the allelopathic effect of weeds frequently inhibited the germination and seedling growth of crops. johnsongrass (sorghum halepens) is known to contain water-soluble substances that are allelopathic. to identify the allelopathic effect of johnsongrass, the effect of different aqueous extracts (0, 5, 10, 20, 30, 40 and 50 g l-1) obtained from roots and leaves of johnsongrass on the seed germinat...

study of agronomic characteristics and advantage indices in intercropping of additive series of chickpea (cicer arietinum l.) and black cumin (nigella sativa l.) abstract in order to evaluate quantitive and qualitive yield of chickpea (cicer arietinum l.) and black cumin (nigella sativa l.) in intercropping of additive series, a field experiment was arranged in a randomized complete block desig...

this experiment was set to study the allelopatic effect of aqueous and alcoholic extracts of artemisia, coriander, eucalyptus and cumin on growth of red root pigweed and lambsquarters weeds at laboratory and field in the university of tehran (karaj-iran) in 2008. the herbal plant samples were ground and powdered for extraction preparation, and were mixed with distilled water in a beaker. the ex...