Seed health testing and evaluation of infected seed quality compared to non-infected seed of some rangeland and medicinal plant species

Reference to the International Seed Testing Association, seed health testing is the most important aspect  of  seed testing. The seed borne fungi and insects cause reduction of viability and vigor of the seed samples. Therefore, seed  health test should be considered in seed testing. In this research, seed samples of some species collected from different regions of Iran, were chosen for seed health testing. After cleaning and determination of physical purity, the seed samples were analyzed for determination of seed borne mycoflora (fungi) and insects. Damaging effects of seed borne pest were observed on the seed samples, but there were not any life cycles of  insect (adult, larva and pupa). The infected seeds were separated from healthy seed. Also for determination of mycoflora (seed borne fungi), with the trace of damaging, shapes of symptoms on the seed and their colour were used for identification of healthy seeds from non-healthy seeds. The infected seeds were cultured on Potato Dextroz Agar (PDA), after
growing of  fungi, four genera called Penicillium, Alternaria, Aspergilus, Rhizopus and Fusarium were isolated from the seed samples. Moreover, the seed quality (percentage of  germination and  speed of germination) of  infected seeds to seed borne fungi were compared to healthy seeds.