The Effects of Gibberellic Acid and Scarification on the Seed Dormancy and Germination in Luzula spicata

Abstract

Luzula .spicata L. seeds are completely dormant at maturity. A germination inhibitor is present at the micropylar end. Normally, the only effective means of eliciting germination is a precise scarification of the micropylar end which inactivates the inhibitor. Exogenous application of gibberellic acid, kinetin, KNOy, and thiourea have no affect on the dormancy of unscarified seeds. Scarification of the hilar end of the seed does not elicit germination, but when gibberellic acid is applied to the hilar scarified seeds moderate germination results. Presumably, these seeds are dormant due to a deficit of endogenous gibberellin; a condition which can be overcome by the application of gibberellic acid to seeds scarified at a site in itself ineffective in producing germination. Apparently the gibberellic acid serves to initiate amylase activity in the endosperm, overcoming the inhibitor block. Luzula spicata seed dormancy is apparently unique in that a germination inhibitor is operative in conjunction with the commonly recognized gibberellin-amylase mechanism.

Quebra de dormência de sementes da videira cv. niágara rosada sem estratificação

“…A função do GA 3 na quebra de dormência das sementes está associada à promoção de estímulos que induzem a síntese ou a ativação das enzimas hidrolíticas no endosperma (Mayer & Mayber, 1975;Amen, 1987;Taiz & Zeiger, 1998). Com a aplicação de GA 3 às sementes, prova-Rev.…”

Seed Dormancy in Luzula Spicata and L. Parviflora

“…Stokes (1965) notes that, in seeds requiring both scarification and stratification, usually seed-coat deterioration by soil bacteria or fungi must occur prior to chilling. Since the caruncle of L. spicata prevents growth of fungi and bacteria (Amen 1964), mechanical scarification provides an alternate means for permitting adequate imbibition or oxygen uptake.…”

“…In addition to this apparent physiological peculiarity, the scarification requirement raises an ecological problem. The tundra environment of L. spicata in the Rocky Mountains could provide scarification by abrasion in soil movement by frost action, wind, or meltwater flow (Amen 1964). Scarification must be very precise, however, or damage to the embryo results, preventing germination (Wiles 1965 ; Fig.…”

Characteristics of Growth and Root Development of Peucedanum japonicum Seedling by Shading Rate and Container Size

“…WinRhizo 프로그램 (2009 Version, Regent Instrument Inc., Quebec, Canada)을 이용하여 전체 뿌리의 영상 분석 (root image analysis) 뿐만 아니라 전체뿌리길이 (total root length), 뿌리투영단면적 (total projected root area), 뿌리표면적 (total root surface area), 전체뿌리부피 (total root volume), 평 균뿌리직경 (average root diameter) 등을 측정 • 분석하였으며, 뿌리의 직경등급별로도 전체뿌리길이, 뿌리투영단면적, 뿌리표 면적, 뿌리부피 등을 분석하였다 (Arsenault et al, 1995;Bouma et al, 2000;Wang and Zhang, 2009 (Amen, 1967;Cho and Kim, 1993;Kang et al, 1997;Yu et al, 1995; 1.01 ± 0.26bc 0.11 ± 0.03b 0.23 ± 0.06b 0.02 ± 0.01bc 1.23 ± 0.31b 0.12 ± 0.03b 6.0 ± 1.4bc 50 1.46 ± 0.35a 0.15 ± 0.04a 0.20 ± 0.08b 0.02 ± 0.01b 1.66 ± 0.42a 0.17 ± 0.04a 7.2 ± 2.1b 75…”