After 1 hour, exogenous deoxyribonucleic acid was degraded within a culture medium at 25 C (pH 6) containing protoplasts of Daucus carota L. var. sativa. Low temperature incubation (1 C) or the addition of 45 millimolar sodium citrate to the medium eliminated DNase activity for at least 4.5 hours. This DNase activity was not reduced at pH 7 or 9, nor by addition of 200 millimolar adenosine 5'-t...

A mechanistic model based on synthesis and inactivation of enzymes, associated to the respiration pathway, was proposed to describe wound-induced respiration of fresh-cut produce. Carrots (Daucus carota L.) were cut into slices, sticks, a combination of both, and shreds to obtain different wounding intensities, defined by the ratio of new area created to tissue weight (A/W). Respiration rates o...

Brassicaceae seed meals produce ionic thiocyanate (SCN (-)), a bioherbicidal compound. This study determined the fate of SCN (-) in a field soil amended with seed meals of Sinapis alba, Brassica juncea, and Brassica napus and quantified crop phytotoxicity by monitoring carrot ( Daucus carota) emergence. Meals were applied at 1 or 2 t ha (-1), and soils were sampled to 35 cm for SCN (-). Maximum...

The particulate enzyme fraction from mung bean (Phaseolus aureus) seedlings catalyzes the incorporation of mannose from GDP-[(14)C]mannose into mannosyl-phosphoryl-dolichol and of N-acetylglucosamine from UDP-[(3)H]N-acetylglucosamine into N-acetylglucosamine-pyrophosphoryl-polyisoprenol. Bacitracin inhibits the transfer of both of these sugars into the lipid-linked saccharides with 50% inhibit...

A procedure is described that permits the use of radiotracer methods for examining crown gall tumors in the presence of the initiating agent Agrobacterium tumefaciens. On the basis of sensitivity testing using the disc diffusion technique and the minimum inhibitory concentration procedure and incorporation of radioactive phosphorus into nucleic acids, it was determined that A. tumefaciens was m...

Single nucleotide polymorphisms (SNPs) and insertion-deletions (InDels) are becoming important genetic markers for major crop species. In this study, we focus on variations at genomic level of the Daucus carota L. AOX2a gene. The use of gene-specific primers designed in exon regions on the boundaries of introns permitted to recognize intron length polymorphism (ILP) in intron 3 AOX2a by simple ...

Plant carotenoids are synthesized and accumulated in plastids through a highly regulated pathway. Lycopene β-cyclase (LCYB) is a key enzyme involved directly in the synthesis of α-carotene and β-carotene through the cyclization of lycopene. Carotenoids are produced in both carrot (Daucus carota) leaves and reserve roots, and high amounts of α-carotene and β-carotene accumulate in the latter. In...