Alpha-amylase is expressed at high levels in cotyledons of germinated seeds of Vigna mungo. The mRNA for alpha-amylase appeared in cotyledons of the seeds at 1 d after imbibition started (DAI). Two TGACGT motifs at -445 and at -125 in the promoter region of the gene interacted with nuclear proteins from cotyledons of dry seeds and the activities were detected until 3 DAI. A transient assay with...

A crude homogenate obtained from greening cucumber (Cucumis sativus, L.) cotyledons in tris-sucrose, pH 7.7, containing coenzyme A, glutathione, potassium phosphate, pH 7.7, methyl alcohol, magnesium, nicotinamide adenine dinucleotide, and adenosine triphosphate, is able to incorporate 4-(14)C-delta-aminolevulinic acid into chlorophyll a and b in the presence of oxygen. If the homogenates are p...

The changes in major nitrogenous components during the germination of pea seeds have been followed. During the period of rapid axis growth, 3 to 8 days following germination, the nitrogen content of the cotyledons declines rapidly with an accompanying increase of nitrogen in the developing axis. The accumulation of alcohol soluble nitrogen, primarily amino nitrogen, in the cotyledons and axis d...

Although the consequences of cotyledon removal have been widely studied in oaks producing large acorns, we have little knowledge of at what level cotyledons can be removed without affecting acorn survival and seedling development. In this study, we aimed to test the hypothesis that the amount of energy reserves in cotyledons is more than the demands of seedlings and that large acorns can tolera...

Supplemental methionine in a complete culture medium increased the methionine content of the protein fraction of cultured soybean (Glycine max L. Merrill) cotyledons (Thompson, Madison, Muenster 1981 Phytochemistry 20: 941-945). To explain the observed increase in protein methionine, we have measured the amounts and subunit compositions of 7S and 11S storage proteins and determined the amino ac...

trehalose (a-d-glucosyl-[1,1]-a-d-glucopyranoside) is involved in mechanisms that coordinate metabolism with plant growth adaptation and development. the main objective of the current work was to find out whether trehalose feeding affects the expression of two genes involved in photosynthesis: one gene coding for photosystem1 subunit h (ps1-h) and the other for the light harvesting complex b1 (...

The effects of increasing NaCl concentrations on biomass, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and phenylalanine ammonia-lyase (PAL) in Jatropha curcas L. seedlings were investigated. The fresh weights of cotyledons and radicles with increasing NaCl concentrations decreased progressively, and the fresh weight of hypocotyls reached the lowest level at NaCl concentration ...

Endogenous sinapic acid (SA), sinapine (SP), sinapoyl glucose (SG) and canolol (CAN) of canola and mustard seeds are the potent antioxidants in various lipid-containing systems. The study investigated these phenolic antioxidants using different fractions of canola and mustard seeds. Phenolic compounds were extracted from whole seeds and their fractions: hulls and cotyledons, using 70% methanol ...

Hymenaea courbaril is a leguminous tree species from the neotropical rain forests. Its cotyledons are largely enriched with a storage cell wall polysaccharide (xyloglucan). Studies of cell wall storage polymers have been focused mostly on the mechanisms of their disassembly, whereas the control of their mobilization and the relationship between their metabolism and seedling development is not w...

Three known physiological responses to exogenous cytokinins were measured in wounded and nonwounded cotyledons from cucumber (Cucumis sativus L. cv Marketer) seedlings grown in darkness. Enhanced cell division, chlorophyll formation, and cotyledon expansion were detected in wounded cotyledons. The data suggest that wounding enhances endogenous cytokinin activity.