Effects of halopriming on germination traits of medicinal plant caper small shrub (Capparis spinosa var. parviflora) seeds

Caper (Capparis spinosa var. parviflora) is a winter-deciduous perennial small shrub growing in hot and dry climates. This is well-known as a multipurpose plant. Regarding to its germination difficulties، this study investigates the seed germination of caper under potassium nitrate (KNo3) treatment using the halopriming technique. For this purpose، four concentration levels (0، 50، 100 and 200 mM) and four time levels (0، 24، 48، 72 hours) with three replications were considered as factorial experiment based on the completely randomized design. Some traits including germination percentage، germination speed، mean time of germination، seed vigority index، stem length and root length as well as fresh and dry weight of stem and root were measured. Results show that the halopriming technique significantly affects the germination characteristics of caper seeds، whereas the greatest germination percentage and vigour index were found in treatment of 200 mM-48 hr.، the greatest germination speed in 200 mM-72 hr.، and the greatest fresh weight of stem and root in 200 mM-24 and 72 hr. Results suggest that the halopriming technique can be introduced as a new approach to improve germination of this species، particularly in afforestation activities of aridlands in southern Iran.