In vitro shoot tips of Sequoia sempervirens (D. Don.) Endl.—including a juvenile, two adult, and two rejuvenated adult clones—were examined for differences in basic physiological characteristics. Moisture contents were the same, around 85%, for all tissues regardless of origin. Growth rates, determined by fresh weight increase and shoot elongation, were higher for the juvenile and rejuvenated s...

Shoot branching is a primary contributor to plant architecture, evolving independently in flowering plant sporophytes and moss gametophytes. Mechanistic understanding of branching is largely limited to flowering plants such as Arabidopsis, which have a recent evolutionary origin. We show that in gametophytic shoots of Physcomitrella, lateral branches arise by re-specification of epidermal cells...

The functions of the vast majority of genes encoding R2R3 MYB domain proteins remain unknown. The closely related MYB33 and MYB65 genes of Arabidopsis thaliana have high sequence similarity to the barley (Hordeum vulgare) GAMYB gene. T-DNA insertional mutants were isolated for both genes, and a myb33 myb65 double mutant was defective in anther development. In myb33 myb65 anthers, the tapetum un...

Ex situ conservation is critical for hedging against the loss of plant diversity. For those species (exceptional species) that cannot be conserved long-term in standard seed banks, alternative methods are required, often involving in vitro culture and cryopreservation, or storage in liquid nitrogen. Cycladenia humilis var. jonesii is a federally threatened perennial native to Utah and Arizona. ...

BACKGROUND Plant body plans arise by the activity of meristematic growing tips during development and radiated independently in the gametophyte (n) and sporophyte (2n) stages of the life cycle during evolution. Although auxin and its intercellular transport by PIN family efflux carriers are primary regulators of sporophytic shoot development in flowering plants, the extent of conservation in PI...

Valeriana officinalis is an important medicinal herb commonly found in Kashmir valley. This study forms an important preliminary step for in-vitro micro propagation of V. officinalis from breaking the seed dormancy, inducing rapid seed germination and its subsequent micro propagation. We investigated the influence of pretreatment of V. officinalis seeds with reduced temperature and light on see...

Root system growth and development is highly plastic and is influenced by the surrounding environment. Roots frequently grow in heterogeneous environments that include interactions from neighboring plants and physical impediments in the rhizosphere. To investigate how planting density and physical objects affect root system growth, we grew rice in a transparent gel system in close proximity wit...

The objective of this study was to investigate the effect cytokinins benzylaminopurine (BAP) and Kinetin on in vitro shootregeneration shoot tips Polyscias balfouriana marginata. Shoot were cultured Murashige Skooge (1962) medium (MS) supplemented with various concentrations BAP at 0.0, 0.75, 1.5, 3, 6 mg/L for both. Results showed that marginata responded positively growth regulators applicati...

Tendrils produced from shoot tips of grapevine (Vitis vinifera L.) cultured in vitro on Nitsch's medium developed into inflorescences when 5 to 10 mum benzyladenine (BA) or 6-(benzylamino)-9-(2-tetrahydropyranyl)-9H-purine (PBA) were applied directly to the tendril tips. Inflorescences did not form on tendrils if the cytokinins were supplied in the agar. Tendrils cultured in agitated liquid med...