pulvinus


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pulvinus

a mass of thin-walled cells at the base of the leaf petiole in certain plants, forming a swollen area surrounding the vascular tissue. The pulvinus is subject to large changes in TURGOR. For example, in the runner bean the pulvinus is turgid during the day and supports the petiole, so that the leaf is held outwards. At night the pulvinal cells loose turgidity and the leaf droops. These diurnal leaf positions are sometimes called sleep movements. The sudden change in leaf posture observed in Mimosa sensitiva when touched is also controlled by pulvinal cells.
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Indumentum hispidulous, constituted of trichomes glandular and tector, thin and stellate, colourless to whitish or orange, soft, rigid, erect, tangles, 0.5-3 mm long, distributed on the branches, pulvinus, petioles, stipite of nectary, leaflets, inflorescence axis, bracts and pedicels.
Leaves 1.8-7.3 cm long; pulvinus green-vinaceous, pilose, c.
Leaves 3-10.5 cm long; pulvinus green, glabrous, c.
These findings can provide a better understanding of the circadian pattern of protein expression in the legume pulvinus proteome.
For many plants, particularly leguminous species, the site of light perception is in the pulvinus, a histologically distinct tissue located at the base of the leaf [4].
Some studies isolating adaxial and abaxial pulvinus protoplasts have shown the same physiological response to a given stimulus for both regions.
pulvinus (also pulvinar): either of two convex forms on an Ionic capital having on their ends two of the volutes.
Of the four species studied here, only Heliocarpus has a well-developed pulvinus, at the attachment point of the petiole and the leaf.
Leaves 1.8-9 cm long; petiole 6-17 mm long; pulvinus 0.6-1.3 mm diam; rachis 1.7-8.5 cm long, interfoliolar segments 0.2-0.9 cm long; extrafloral nectaries 5-15, fusiform, shortly stipitate or stipitate, located between all pairs of leaflets, 0.8 1.5 x c.
Leaves 4.5-12.5 cm long; petiole 3-15 mm long; pulvinus 1.3-2.2 mm diam; rachis 3.6-8.2 cm long, interfoliolar segments 0.6-2 cm long; extrafloral nectaries 3-7, claviform and fusiform, stipitate, located between all pairs of leaflets, occasionally absent in the proximal pair or 0-2 in the distal, 2-3 x 0.2-0.6 mm; leaflets 3-7 pairs, chartaceous, adaxial surface strigose, the distal 10-50 x 4-23 mm, the proximal 10-40 x 4-12 mm, elliptic, lanceolate, oblong, ovate and oval-lanceolate, venation craspedodromous, nervures 9-11 pairs, apex acute, acute-mucronate, obtuse, obtuse-mucronate, acuminate and rarely emarginate, base oblique and subcordate, margin revolute, ciliated.
Leaves 4-11 cm long; petiole 9-27 mm long; pulvinus 0.7-1.8 mm diam; rachis 0.6-1.8 cm long, extrafloral nectaries 1, ovoid, claviform and fusiform, sessile or shortly stipitate, located between the proximal pair of leaflets, 1.2-1.5 x 0.2-0.7 mm; leaflets 2 pairs, papyraceous, abaxial surface pubescent and adaxial surface puberulent, the distal 30-55 x 15-28 mm, the proximal 14-43 x 7-24 mm, ellipticoblanceolate, lanceolate-elliptic, obovate, ovate, venation brochidodromous, nervures 7-13 pairs, apex emarginate, short mucronate and obtuse, base cuneate, oblique, obtuse, subcordate, margin revolute, ciliated.
Heat Retention and Herbivory Benefits of the Pulvinus Organ