Abstract:

In order to screen high-quality seed sources of pickled Nitraria sphaerocarpa for artificial cultivation， 25 pickled Nitraria sphaerocarpa seeds were collected as materials in the Gobi Desert Beach， in front of the Hexi Corridor and the desert sand to study their physical characteristics， dormant characteristics， dormant destruction methods and germination characteristics. The results show that the foam Nitraria sphaerocarpa seeds are spindle-shaped or needle-shaped， with milky yellowish-brown colors， and a very few are black-brown. The outer skin of the seeds is soft and the surface is rough. The seed length is 7.01-9.29 mm， the width is 1.90-2.63 mm， the shape index is 5.41-11.18， the thousand grain weight is 8.28-19.23 g， the specific gravity is 1.02-1.16 g·cm^-3， the volume weight is 282.17-448.33 kg·L^-1， the soundness is 34.5%-92%， the initial germination rate is 4.25%-30.25%， and the indicators of different sample seeds have reached a very significant difference （P<0.01）； the seed specific gravity is extremely positively correlated with the seed soundness （P<0.01）， the seed soundness is extremely positive correlation cleaning the seed with NaOH， Ca（OH）₂ or KOH solution can remove the seed germination inhibitors and release the seed dormant completely. After breaking the dormancy， the germination rate of 25 foam fruit white thorn seeds is between 13% and 90%， the average germination days is 1.88-2.95 d， and the germination index is 4.03-34.07. Under suitable conditions， the seed of pickled fruit is a sharp water absorption period within 2 h after being put on the bed， a slow water absorption period of 2 to 14 h， and a saturated water absorption period after 14 h. The water absorption rate remains at 60%， the material efficiency reaches 67.09% during seed germination， and the seedlings formed by seed germination are dicotyledon leaf seedlings.

Key words: Nitraria sphaerocarpa seed, Hexi Corridor, dormant rupture, germination rate, phenotype difference