Potato tubers (Solanum tuberosum L. cv. Binje) were stored at 18 and 4oC in order to verify changes in mitochondrial metabolism, especially in the activities of the alternative oxidase (AOX) and plant uncoupling mitochondria protein (PUMP). Tubers were also sliced and submitted to artificial aging. The oxygen consumption rate (OCR), respiratory control (RC) and ADP/O ratio for mitochondria obta...

Excision of developing potato (Solanum tuberosum L.) tubers from the mother plant, followed by storage at 10 degrees C, resulted in a rapid, substantial decrease in sucrose synthase activity and considerable increases in hexose content and acid invertase activity. A comparison of the response of three genotypes, known to accumulate different quantities of hexoses in storage, showed that both su...

Tuberous sclerosis (TSC) is a multi-organic, autosomal-dominant disorder commonly caused by mutations in one of the two tumor suppressor genes TSC1 or TSC2 that encode the proteins hamartin and tuberin, respectively. TSC is characterized by highly differentiated malformations in different organs, including cortical tubers in the brain. They occur in the majority of patients and represent the ma...

Liquid suspensions and dry formulations of a granulovirus (family Baculoviridae, genus Granulovirus, PoGV) derived from infected larvae and the bacterium Bacillus thuringiensis subsp. kurstaki (Berliner) (Btk) were evaluated for control of the potato tuberworm, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), in stored tubers. Laboratory bioassays at 25 degrees C showed that both Po...

Rhizomes of Acorus calamus L. were able to maintain a functional alpha-amylase under anoxia, whereas a steep decrease in the enzyme protein content and activity took place in potato tubers. The stress-induced control in tubers occurred on the translational level. It is suggested that this decrease is one of the key factors with regard to anoxia intolerance.

Gene expression in nongreen plastids is largely uncharacterized. To compare gene expression in potato (Solanum tuberosum) tuber amyloplasts and leaf chloroplasts, amounts of transcripts of all plastid genes were determined by hybridization to plastome arrays. Except for a few genes, transcript accumulation was much lower in tubers compared with leaves. Transcripts of photosynthesis-related gene...

To help learn how phytopathogens feed from their hosts, genes for nutrient transporters from the hemibiotrophic potato and tomato pest Phytophthora infestans were annotated. This identified 453 genes from 19 families. Comparisons with a necrotrophic oomycete, Pythium ultimum var. ultimum, and a hemibiotrophic fungus, Magnaporthe oryzae, revealed diversity in the size of some families although a...

Trehalose-6-phosphate (T6P) is a signaling metabolite that regulates carbon metabolism, developmental processes, and growth in plants. In Arabidopsis (Arabidopsis thaliana), T6P signaling is, at least in part, mediated through inhibition of the SNF1-related protein kinase SnRK1. To investigate the role of T6P signaling in a heterotrophic, starch-accumulating storage organ, transgenic potato (So...

The protein content and amino acid profile of Anchote (Coccinia abyssinica) leaves and tubers were determined from ten different accessions taken from Debre Zeit Agricultural Research Center, Ethiopia. Crude protein content was determined by Kjeldahl method and amino acid profile was analyzed using performic acid oxidation and acid hydrolysis by ninhydrin-derivatized analysis with amino acid an...

We showed recently that antisense plants with decreased activity of the plastidic ATP/ADP-transporter protein exhibit drastically reduced levels of starch and a decreased amylose/amylopectin ratio, whereas sense plants with increased activity of the transporter possessed more starch than wild-type plants and an increased amylose/amylopectin ratio. In this paper we investigate the effect of alte...