Seed Germination of Selected Provenances of Atlantic White-Cedar as Influenced by Stratification, Temperature, and Light

Abstract

<jats:p>Seeds of six provenances (Escambia Co., Ala.; Santa Rosa Co., Fla.; Wayne Co., N.C.; Burlington Co., N.J.; New London Co., Conn.; and Barnstable Co., Mass.) of Atlantic white-cedar [<jats:italic>Chamaecyparis thyoides</jats:italic> (L.) B.S.P.] were stratified (moist-prechilled) for 0, 30, 60, or 90 days at 4 °C. Following stratification, seeds were germinated at 25 °C or an 8/16-hour thermoperiod of 30/20 °C with daily photoperiods at each temperature of 0 (total darkness), 1, or 24 hours. The germination of nonstratified seed did not exceed 18%. Seeds germinated at 25 °C required 60 to 90 days stratification to maximize germination. In contrast, 30 days stratification maximized germination at 30/20 °C. Regardless of stratification duration, germination was generally lower at 25 °C than at 30/20 °C for each provenance. Averaged over all treatments, seeds of the Alabama provenance exhibited the greatest germination (61%), followed by those from Florida (45%), with the remaining provenances ranging from 20% to 38%. However, specific treatments for each provenance induced germination &gt;50%. Germination of seeds not exposed to light was &lt;8%, in contrast with 48% and 55% germination for daily photoperiods of 1 and 24 hours, respectively. Seeds from each of the provenances, except for Alabama, exhibited an obligate light requirement when germinated at 25 °C. At 30/20 °C, the North Carolina, New Jersey, Connecticut, and Massachusetts provenances required light for germination, whereas the Alabama and Florida provenances did not.</jats:p>

Germination Behavior and Early Seedling Growth in Abies pinsapo Boiss. Seeds

“…Contrarily to the rest of the populations in which no light effect was observed, significantly higher germination rates were achieved in darkness in seeds from Grazalema. A differential light effect depending on the seed origin was also found in Chamaecyparis thyoides [ 35 ], Pinus canariensis and Pinus halepensis [ 19 ]. Therefore, although in conifer seeds light sensitivity appears to be determined by the species [ 21 ], intraspecific variations can also be expected, especially in species with a wide geographical distribution [ 19 ].…”

“…Interpopulation variability in germination is considered a general trend in conifer species [ 19 ]. Thus, intraspecific differences have been reported in Abies guatemalensis [ 36 ], Abies koreana [ 37 ], Pinus nigra [ 19 , 22 ], Pinus pinea , Pinus pinaster [ 19 ], Chamaecyparis thyoides [ 35 ], Pinus flexilis and Picea engelmannii [ 26 ]. Differences in germination capacity among seeds from different provenances have been attributed to genetic variations [ 25 , 38 ], although an important influence of the maternal environment has also been pointed out [ 39 ].…”

Evaluation of the influence of dendrometric and ecological factors on the natural regeneration of “Cedrus Atlantica Mannetti” In Ain Antar forest, Algeria

“…Compared to its longevity and early fruiting that appears from 15-20 years, natural regeneration or seedling cycle of the Atlas cedar is subject to strict environmental constraints; determined by the requirements of the species vis-a-vis water, soil and cold (Toth, 1980;Illoul et al, 2004;krouchi et al, 2004). Hinesley et al (1994) and Jull and Blazich (2000) reported the inability of Atlas cedar to compete on dry sites. Drought is an important factor in seedling mortality.…”

Rangewide provenance variation in Atlantic white-cedar (Chamaecyparis thyoides): Early survival and growth in New Jersey and North Carolina plantations

“…Under controlled conditions, Jull et al (1999) found different temperature optima for seedlings of six provenances, ranging from 21 8C for Massachusetts seedlings to 25 8C for Alabama seedlings. In another study, Jull and Blazich (2000) showed that stratification requirements for seed germination varied among provenances. The available data, though based on a small number of populations, provide some evidence of adaptively relevant geographic variation.…”