In the tetraploid Tulipa sylvestris we found larger and heavier seeds that germinated around 28 days earlier than those of the diploid ancestor Tulipa pumila. The faster germination of the tetraploid species is linked to the faster growth of embryos, which reached their final length much earlier than the embryos of the diploid species. In conclusion, we argue a cautionary approach when dealing with comparative studies on ploidy level and germination to avoid misinterpretation of results when set against the natural conditions.

Plots of western false hellebore (Veratrum californicum Durand), treated in 1968 and 1969 with 2,4-D [(2,4-dichlorophenoxy)acetic acid] at 2.2 kg/ha, were reexamined in July 1979 to determine vegetative changes, especially any increases in the production of desirable species and long-term control of western false hellebore. Grass, sedge, and rush production had doubled, and broadleaved plant production, excluding western false hellebore, which was eliminated, decreased on treated plots. Western false hellebore had not reinvaded the treated plots; control remained at 100% for 10 yr. Removal of the western false hellebore on treated plots allowed an increase in grass, sedge, and rush production of 1,500 kg/ha over check plots.

Experimental plots treated with 2,4-D amine at 2.2 kg ae ha-1 in 1968 and 1969 to control California false-hellebore were evaluated in July 1989 to determine long-term control of California false-hellebore, changes in foliar cover, and increases in production of desirable species. Control of California false-hellebore was 100% on all treated plots. The foliar cover on treated plots averaged 78% grasses and sedge, 20% broadleaf plants, and no California false-hellebore. Control plots averaged 85% California false-hellebore, 10% grasses and sedge, and 4.5% broadleaf plants. Vegetative production of grasses and sedge was 3.8 times greater on treated plots compared with controls.

Fritillaria tubiformis subsp. moggridgei (Liliaceae) is a rare, endemic species that inhabits open mountains and alpine grasslands of the Ligurian Alps. At the time of seed dispersal, the underdeveloped embryos were 27% the length of the seed. Here we report the results of laboratory experiments carried out to determine the temperature preferences for embryo growth and radicle emergence. Embryo growth commenced immediately after sowing at 4°C. Once the embryo had grown the length of the seed, the radicle emerged. The time required for embryo growth and radicle emergence was longer when seeds were placed through a seasonal sequence of temperatures, commencing with late summer (10/20°C), compared with seeds immediately placed at a temperature to simulate winter conditions (4°C). Prematurely transferring seeds from winter to spring temperatures (5/10°C) also slowed the progress of germination. Radicle emergence did not occur at 10 or − 5°C and less than 20% germination occurred in seeds placed at constant 0°C. Addition of gibberellic acid (GA3) did not promote embryo growth of seeds placed at 20°C. Overall, the temperature preferences for embryo growth and subsequent radicle emergence are such that, in situ, seed germination may occur during the winter under snow cover or at the end of winter to coincide with snow melt and warming temperatures.

Ecophysiological aspects of seed germination were investigated in four Mediterranean geophytes of the genus Muscari (Liliaceae): M. comosum (tassel hyacinth), M. neglectum (common grape hyacinth), M. commutatum and M. weissii. Experiments were performed at constant temperatures in the dark and under temperature and light conditions simulating those prevailing in nature during November–January, i.e. well into the rainy season of the Mediterranean climate. In all species, no primary dormancy was revealed, and germination occurred in a rather narrow range of cool temperatures (optimum at 10 or 15°C) and at a remarkably slow rate; both germination characteristics seem to be associated with autumn/winter seed germination and seedling establishment. Such a postulated strategy is ecologically advantageous within an unpredictable rainfall regime, known to prevail during the start of the rainy period of the Mediterranean climate. This strategy may also explain the spread of germination of M. comosum seeds over two consecutive years, observed by Theophrastus. Far-red light, simulating light conditions under a dense canopy, resulted in only a slight delay of germination compared to dark controls. Diurnal white light, qualitatively simulating natural daylight, caused a significant decrease of the germination rate in all four species studied. Moreover, white light was found to suppress considerably final seed germination (photoinhibition) in M. weissii and M. neglectum; in the latter species, prolonged imbibition under white light also led to the induction of secondary dormancy.

Asparagus lycaonicus P.H. Davis (Asparagaceae), a species hitherto known only from E Central Turkey, is reported from Iran. A review of Nitraria (Zygophyllaceae) in Iran together with critical comments on the account of the genus in Flora Iranica are given, and Iranian records of N. komarovii Iljin & Lava are referred to Atraphaxis suaedifolia Jaub. & Spach (Polygonaceae).