BACKGROUND AND AIMS Lady's slipper orchids (Paphiopedilum) are of high value in floriculture, and interspecific hybridization has long been used for breeding improved cultivars; however, information regarding the genome affinities of species and chromosome pairing behaviour of the hybrids remains almost unknown. The present work analyses the meiotic behaviour of interspecific hybrids by genomic...

The expression of HeLa parent phenotype protein markers, the alpha subunit of human chorionic gonadotropin and placental alkaline phosphatase isoenzymes, has been evaluated in paired tumorigenic and nontumorigenic HeLa-fibroblast human cell hybrids. Both of these proteins have been used clinically as markers of malignancy. The results showed that both are expressed in the hybrids. Expression of...

The host status of 50 commercial maize hybrids for a Mississippi population of Rotylenchulus reniformis was determined in greenhouse experiments. Reproduction was measured by determining RF values ([final egg number + juveniles and vermiform adults in soil] / initial egg number) and number of eggs per gram of fresh root. All hybrids maintained R. reniformis below the initial population level, i...

in order to study the response of new sugar beet hybrids and cultivars to curly top disease in the field conditions, an experiment was carried out in a randomized complete block design with four replications and sixteen treatments in 2007 in fasa. each plot included a hybrid or cultivar planted in three rows with eight meter length and 50cm between- row spacing. after weeding and first thinning...

The host suitability of 64 commercial corn hybrids for a Meloidogyne arenaria race 2 population and a M. incognita race 4 population was determined in greenhouse experiments. 'Northrup King 508' and 'Pioneer Brand 3147' maintained M. arenaria below and at the initial population level, respectively, indicating that these hybrids are relatively poor hosts for this species. RF values (final egg nu...

To determine the chromosomal location of mouse immunoglobulin heavy chain structural genes unambiguously, a panel of somatic cell hybrids was scored for the presence of DNA sequences homologous to gamma 2b-, mu-, and alpha-heavy chain-constant region DNA probe molecules. The hybrids, formed between mouse and hamster cells, contained various combinations of mouse chromosomes plus a full set of h...

Organic-silica hybrids were synthesized from the Si8O20 8ÿ silicate anion by the reaction with an excess of dimethyldichlorosilane. The structure of the hybrids has been found to comprise the Si8O20 8ÿ structure as a building block, linked by the (CH3)2Si unit. Si NMR signals from terminal groups in the hybrids have been assigned. When the amount of dimethyldichlorosilane present for the reacti...

Sweet corn (Zea mays L.) producers desire high yields and high sugar content in the endosperm. High irrigation levels result in high yield, but their effect on sugar content is unclear. The effects of two irrigation levels, standard and stressed on endosperm sugar content were evaluated using three sugary1 hybrids over 2 years. No significant differences were found among the treatments when ave...

Hybrids can exhibit unique combinations of the physiological traits of their parents. These particular combinations may influence hybrid fitness and the evolutionary trajectory of a hybrid zone. Here, a hybrid zone between Penstemon newberryi and Penstemon davidsonii along an elevational gradient was examined, and physiological traits of parents and hybrids were measured in their native environ...

Natural hybridization can produce individuals that vary widely in fitness, depending upon the performance of particular genotypes in a given environment. In a hybrid zone with habitat heterogeneity, differences in physiological responses to abiotic conditions could influence the fitness and spatial distribution of hybrids and parental species. This study compared gas exchange physiology of Ipom...