Plant Development: Dual Roles of Poplar SVL in Vegetative Bud Dormancy

Reproductive buds broke dormancy at the same time as vegetative buds. Pollen mother cells entered prophase of meiosis immediately after dormancy and five-celled, winged pollen was mature about 6 weeks later. Megasporogenesis occurred 3 weeks after microsporogenesis and the female gametophyte was mature in about 6 weeks. Pollination occurred over about 1 week in late May or early June and fertilization occurred about 3 weeks after pollination. One to four archegonia developed. A comparable number of 16-celled proembryos usually developed within 1 week after fertilization and cotyledons began to develop about 1 month after fertilization. Simple polyembryony occurred in most ovules but cleavage polyembryony was not observed. Embryos were fully developed in late August and seeds were mature and shed in September.The small number of archegonia often present, the high incidence of self-pollination, which may have been the cause of the high frequency of early embryo abortion, and the failure of basal and distal ovules to become pollinated were major causes of empty seed.The phenology of reproductive development varied with the site and the elevation but varied little at one site in successive years. Differences were greatest early in the growing season, but by the time of fertilization, higher elevation trees which began development much later had nearly caught up with lower elevation trees and seeds from all sites were mature and shed at about the same time.Reproductive bud dormancy like vegetative bud dormancy was broken in response to photo-period rather than temperature; however, subsequent cone development was greatly affected by temperature.

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Changes in Parameters of the Plasmalemma ATPase during Peach Vegetative Bud Dormancy

Biologia Plantarum ◽

10.1023/a:1026538526649 ◽

2000 ◽

Vol 43 (1) ◽

pp. 25-29 ◽

Cited By ~ 6

Author(s):

H.-L. Aue ◽

I. Lecomte ◽

G. Petel

Keyword(s):

Bud Dormancy ◽

Vegetative Bud

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Genetics of Length of Dormancy Period in Malus Vegetative Buds

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.1.121 ◽

1991 ◽

Vol 116 (1) ◽

pp. 121-126 ◽

Cited By ~ 23

Author(s):

Roberto Hauagge ◽

James N. Cummins

Keyword(s):

Interspecific Hybrids ◽

Dominant Gene ◽

Bud Dormancy ◽

Broad Sense Heritability ◽

Narrow Sense Heritability ◽

Winter Conditions ◽

Dormancy Period ◽

Chilling Requirements ◽

Heritability Estimates ◽

Vegetative Bud

In a study of chilling requirement in Malus, broad-sense heritability estimates for the length of vegetative bud dormancy in 43 clones growing under simulated subtropical winter conditions were 0.76 ± 0.04 in 1986 and 0.81 ± 0.04 in 1987. Narrow-sense heritability estimates were 0.66 ± 0.13 in 1986 and 0.69 ± 0.13 in 1987. Seedlings with low chilling requirements (CR) were not observed in crosses where both parents had high bud-chilling requirements. `Koningszuur' did not transmit its long CR to its seedlings. Open-pollinated (OP) seedling populations from the Malus × domestics Borkh. cultivars Anna, Dorsett Golden, Ein Shemer, Khashabi, Winter Banana, and Zabaoani, and the species and interspecific hybrids M. baccata L. DE#98, M. brevipes Rehd., M. ×robusta (Carr.) Rehd. DE#485, M. × robusta No. 5 (`R5'), M. rockii, M. turesi Rehd. PI 34143, and `Rosedale' had at least 5% of their descendants in the lower CR classes. In all but one instance, 50% or more of `Anna' descendants had low CR. Many of these seedlings were within a few classes of the extreme low CR. It is postulated that the low-CR character present in `Anna' is controlled by at least one major dominant gene and that minor genes interact to modulate its effects. Very low-CR cultivars have a shallow bud dormancy. This highly heritable component for low bud CR is related to a failure to develop a deep dormancy state, rather than to acceleration of the termination of the dormancy process.

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ptr-MIR169 is a posttranscriptional repressor of PtrHAP2 during vegetative bud dormancy period of aspen (Populus tremuloides) trees

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2013.01.027 ◽

2013 ◽

Vol 431 (3) ◽

pp. 512-518 ◽

Cited By ~ 15

Author(s):

Rewati Potkar ◽

Jill Recla ◽

Victor Busov

Keyword(s):

Populus Tremuloides ◽

Bud Dormancy ◽

Dormancy Period ◽

Vegetative Bud

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Bud development in Picea glauca. I. Annual growth cycle of vegetative buds and shoot elongation as they relate to date and temperature sums

Canadian Journal of Botany ◽

10.1139/b77-312 ◽

1977 ◽

Vol 55 (21) ◽

pp. 2728-2745 ◽

Cited By ~ 21

Author(s):

John N. Owens ◽

Marje Molder ◽

Hilary Langer

Keyword(s):

Picea Glauca ◽

Shoot Growth ◽

Shoot Elongation ◽

Growth Cycle ◽

Bud Dormancy ◽

Annual Growth ◽

Bud Development ◽

Leaf Initiation ◽

Vegetative Buds ◽

Vegetative Bud

Vegetative buds of Picea glauca (Moench) Voss were studied throughout the annual growth cycle in several trees in 1975 and 1976 and bud development was related to lateral vegetative shoot growth, date, and temperature sums.Vegetative buds became mitotically active in mid-April at lower elevations and about 6 weeks later at higher elevations. Shoot elongation was characterized by similar smooth sigmoid curves in both years. Shoot growth was slow for the 1st month, rapid during the 2nd month, and slow again for the 3rd month and ended by early August. Temperature sums related best to percentage of shoot elongation if the end of vegetative bud dormancy was used as the starting date and 5 °C was used as the threshold temperature. Arbitrarily chosen starting dates and threshold temperatures gave temperature sums which were related to shoot elongation only when shoot elongation was nearly completed. Generally, if the end of vegetative bud dormancy is known, the number of days from that time is nearly as accurate as the more complex use of temperature sums in predicting the percentage of shoot elongation or the stage of vegetative bud development.Bud-scale initiation occurred during shoot elongation. Axillary buds were initiated in mid-May and flushing occurred when shoots had elongated to about 30% of their final length in late May or early June. The end of shoot elongation coincided with the onset of leaf initiation on all trees in both years. The change from bud-scale initiation to leaf initiation was preceded by a marked increase in apical width and a slight increase in apical height and mitotic frequency. Leaf initiation was rapid for 6 weeks then slower for the last 4 weeks. Vegetative buds became dormant in mid-October.Vegetative bud development is closely related to shoot elongation. Breaking of vegetative bud dormancy was not affected by temperature but shoot elongation and flushing were affected by temperatures which occurred after dormancy was broken.

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