Abstract Triticum monococcum L. and T. boeoticum L., diploid wild relatives of bread wheat ( aestivum L.), possess resistance to leaf rust (also known as brown rust) caused by Puccinia triticina Eriks. Haustorium formation-based mechanisms (i.e. pre-haustorial post-haustorial resistance) have been studied reported in various accessions. In the present study, mechanism accessions was using confo...

Pattern formation and morphogenesis require coordination of cell division rates and orientations with developmental signals that specify cell fate. A viable mutation in the TILTED1 locus, which encodes the catalytic subunit of DNA polymerase epsilon of Arabidopsis thaliana, causes a lengthening of the cell cycle by approximately 35% throughout embryo development and alters cell type patterning ...

Free abscisic acid (ABA) content in suspensors, embryos, and integuments was determined during seed development of Phaseolus coccineus. A highly specific and sensitive solid-phase radioimmunoassay based on a monocional antibody raised against free (S)-ABA was used for ABA quantification. Very small amounts of ABA were detected in the suspensor during initial stages of development; later two pea...

Developmental transitions in some parasitic angiosperms are tied directly to host-derived chemical cues (xenognosins). The obligate hemi-parasite Striga asiatica, initiates the root apical meristem population (germination), development of the host attachment organ (the haustorium), and shoot apical meristem initiation (seed coat shedding) in response to specific xengonosins. These checkpoints s...

Thin sections of petrified fossils made during the latter part of the nineteenth and early twentieth centuries to investigate the internal tissue systems of plants now provide an important new source of information on associated micro-organisms. We report a new heterokont eukaryote (Combresomyces williamsonii sp. nov.) based on exquisitely preserved fossil oogonia, antheridia and hyphae from th...

I. The Importance of Powdery Mildews. . . . . . . . 51 II. Life Cycle of Powdery Mildews . . . . . . . . . . . . . 53 A. Asexual Reproduction. . . . . . . . . . . . . . . . . . 53 B. Sexual Reproduction . . . . . . . . . . . . . . . . . . . 53 III. Interactions with the Host Plant . . . . . . . . . . . . 55 A. Influence on Host Metabolism. . . . . . . . . . . 56 B. Induced Susceptibility and Re...

Abstract Parasitic plants infect other by forming haustoria, specialized multicellular organs consisting of several cell types, each which has unique morphological features and physiological roles associated with parasitism. Understanding the spatial organization types is, therefore, great importance in elucidating functions haustoria. Here, we report a three-dimensional (3-D) reconstruction ha...