Phenotypic plasticity in seed provisioning is a widespread phenomenon in plant populations that is often manifested as environmentally induced maternal effects. Environmental maternal effects can be beneficial if they influence population dynamic functions of seeds in a way that increases fitness, such as escaping from crowding. Using the winter annual plant, Dithyrea californica, we studied th...

The phloem is a highly specialized long distance transport tissue in vascular plants. Despite detailed knowledge of the development and ultrastructure of phloem tissue in a wide variety of plant species, surprisingly little is known about the mechanisms and regulation of phloem transport. The main function of the phloem is transport of the immediate products of photosynthesis (e.g., sugars) fro...

It is one thing to show that herbivorous insects affect plant performance. It is an entirely different matter to demonstrate that insect herbivory affects plant population dynamics. There is a vast literature on insect pests of crop plants that shows how attack by defoliating, sucking, stem-mining, and gall-forming species can delay seed ripening, reduce seed production and individual seed weig...

The stink bug Dichelops furcatus (F.) (Heteroptera: Pentatomidae) has increased in abundance in recent years on the wheat, Triticum aestivum L., crop cultivated in the southern region of Brazil. To investigate the probing (stylet penetration) behaviors and nonprobing behaviors of D. furcatus on wheat plants, the electrical penetration graph or electropenetrography (EPG) technique was applied. N...

Phytochromes are plant photoreceptors important for development and adaptation to the environment. Phytochrome A (PHYA) is essential for the far-red (FR) high-irradiance responses (HIRs), which are of particular ecological relevance as they enable plants to establish under shade conditions. PHYA and HIRs have been considered unique to seed plants because the divergence of seed plants and crypto...

Phytobeneficial microbes, particularly endophytes, such as fungi and bacteria, are concomitant partners of plants throughout its developmental stages, including seed germination, root and stem growth, and fruiting. Endophytic microbes have been identified in plants that grow in a wide array of habitats; however, seed-borne endophytic microbes have not been fully explored yet. Seed-borne endophy...

Herbivory induces plant defenses. These responses are often costly, yet enable plants under attack to reach a higher fitness than they would have reached without these defenses. Spider mites (Tetranychus ssp.) are polyphagous plant-pests. While most strains of the species Tetranychus urticae induce defenses at the expense of their performance, the species Tetranychus evansi suppresses plant def...

a haploid organism directly leads to an altered phenotype, making forward and reverse genetic approaches more straightforward in haploid moss than in diploid seed plants. A major additional asset of mosses came from the discovery that, in the moss Physcomitrella patens, recombination occurs between DNA introduced into cells by transfection and homologous sequences in its nuclear DNA. This occur...

Phytochromes are plant photoreceptors important for development and adaptation to the environment. Phytochrome A (PHYA) is essential for the far-red (FR) high-irradiance responses (HIRs), which are of particular ecological relevance as they enable plants to establish under shade conditions. PHYA and HIRs have been considered unique to seed plants because the divergence of seed plants and crypto...

Effective population size (N(e)) is the key parameter for predicting genetic drift associated with germplasm regeneration. A major factor reducing N(e) below the census population size (N(c)) is variation in seed production among plants in a given population. The objectives of this study were to estimate N(e)/N(c) associated with variation in seed production in three model wind pollinated, pere...