Two shrub species, Atriplex halimus L. and Salsola vermiculata L., are considered useful for rehabilitation of degraded rangelands in west Asia and north Africa. They can be established from direct seeding and are capable of self-sowing. In this study, seed storage at dierent temperatures and the in¯uence of fruiting bracts on seed germination were examined for the two species during two seasons. Fruits (utricles) were stored at 20±228C (room temperature), 08C or 7228C. Germination tests were carried out after 33, 56, 90, 152, 272 and 397 d in storage in the ®rst season and after 44, 76, 104, 170, 288 and 412 d in the second season. Seeds were germinated in their fruiting bracts or after bract removal. Bract removal signi®cantly improved seed germination of both shrubs regardless of storage temperature. For S. vermiculata the increase in germination was in the range of 1.3-to 14.7-fold compared with values for the intact fruit in Season 1 and 0.5 to 3.8 in Season 2. Similarly the ranges for A. halimus were 0.5-to 4.2-fold and 0.7-to 5.3-fold in the two seasons respectively. The eect of cold storage was greater on Salsola than on Atriplex. The reduction of the storage temperature from 218C to 08C and 7228C increased the longevity of S. vermiculata seeds by 2.8±46.6 times in Season 1 and by 2.9±2.6 times in Season 2. There was little or no eect on the longevity of A. halimus. A leachate prepared by soaking fruiting bracts from S. vermiculata signi®cantly depressed germination (p 5 0.01), the eect being greater on Salsola seeds (20% reduction) than on Atriplex seeds (8% reduction). A leachate from A. halimus produced a slight but non-signi®cant reduction in germination.
Four experiments were conducted to facilitate the improvement of degraded grasslands in north Syria. The ®rst examined the survival of legume seeds fed to penned Awassi wethers. The second and third observed the germination and establishment of legumes from faecal pellets in the ®eld and in a glasshouse respectively. The fourth explored the possibility of transporting seeds from legume-rich (source) to legume-poor (target) grasslands using commercial¯ocks on communally-owned land. Seeds of small-seeded clovers passed through sheep in greater numbers (58± 72%) than did seeds of larger-seeded species (10±40%). Of the clover seeds Trifolium campestre (seed size 0.45 mg) disintegrated least (72% passage) and T. haussknechtii (seed size 2.68 mg) disintegrated most (10% passage). Recoveries of Medicago noeana and Scorpiurus muricatus seeds were larger than expected on the basis of their seed sizes. Maximum rate of recovery was at 36 h after the seed meal for all species, all seeds were recovered by 120 h and 90% of the recovered seeds were passed in 72 h. Ingestion had little eect on the hardness and viability of most seeds. Experiments 2 and 3 suggested that seeds in pellets germinated and established as successfully as naked seeds. Burial increased establishment, whether in the ®eld or under conditions of low moisture stress in the glasshouse. The small-seeded clovers, T. tomentosum and T. campestre, established most successfully whether from pellets or from naked seeds. About 500 seeds m 72 were successfully transported from the source to the target grassland. About half were Trigonella monspeliaca, a naturally-occurring legume found on both the source and target grasslands. Of the species sown on the source grassland, 115 seeds m 72 of Trifolium campestre (33% of the source seed bank), 62 seeds m 72 of T. tomentosum (27%) and 78 seeds m 72 of T. purpureum (21%) were detected in the target. Few medics were transported (for example, 52% of M. noeana). Apart from Trigonella monspeliaca, Trifolium tomentosum (16 plants m 72 ) was the most frequent species found in the target grassland in the following April. The results suggest that using sheep is a cheap and practical way of dispersing the seeds of pasture legumes and thereby improving the degraded grasslands of north Syria. They clearly demonstrate the role of small-seeded legumes (51 mg) in grassland improvement, especially the small-seeded clovers.
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