Plant Biology Research Research Articles

Mechanisms of sugarcane response to herbivory

Deciphering plant-insect interactions at the molecular level is one of the major topics of interest in contemporary plant biology research. In the last few years, various aspects of the plant response to insect damage have been investigated, including the characterization of direct and indirect responses, the regulation of gene expression resulting from insect attack and the signal transduction pathways. Such research has resulted in the proposal of new methods to enhance host resistance to insect pests, including the use of insecticidal genes that can be transferred by genetic engineering into target crops. By integrating the understanding of how plants react to insect damage with the techniques of molecular biology researchers should be able to increase the wide range of methods available for the control of insect pests. The sugarcane transcriptome project (SUCEST) has allowed the identification of several orthologues genes involved in the plant response to insect damage. In this paper we summarize several aspects of the complex interaction between plants and insects and describe the use of in silico analysis to provide information about gene expression in different sugarcane tissues in response to insect attack.

Realizing the potential of rapid-cycling Brassica as a model system for use in plant biology research.

Rapid-cycling Brassica populations were initially developed as a model for probing the genetic basis of plant disease. Paul Williams and co-workers selected accessions of the six main species for short time to flower and rapid seed maturation. Over multiple generations of breeding and selection, rapid-cycling populations of each of the six species were developed. Because of their close relationship with economically important Brassica species, rapid-cycling Brassica populations, especially those of B. rapa (RCBr) and B. oleracea, have seen wide application in plant and crop physiology investigations. Adding to the popularity of these small, short-lived plants for research applications is their extensive use in K-12 education and outreach.

Statistical considerations for in vitro research: II — Data to presentation

The paper is the second of two papers about statistical considerations that researchers should make while doing in vitro plant biology research. The first paper focused on aspects from developing a plan to do research through the collection of data. This paper continues with information about editing data, handling outliers, analyzing quantitative and qualitative data, comparing treatment means, preparing graphs and tables, and presenting results.

Arabidopsis thaliana: a model plant for genome analysis.

Arabidopsis thaliana is a small plant in the mustard family that has become the model system of choice for research in plant biology. Significant advances in understanding plant growth and development have been made by focusing on the molecular genetics of this simple angiosperm. The 120-megabase genome of Arabidopsis is organized into five chromosomes and contains an estimated 20,000 genes. More than 30 megabases of annotated genomic sequence has already been deposited in GenBank by a consortium of laboratories in Europe, Japan, and the United States. The entire genome is scheduled to be sequenced by the end of the year 2000. Reaching this milestone should enhance the value of Arabidopsis as a model for plant biology and the analysis of complex organisms in general.

Toward a successful multinational crop plant genome initiative.

Plant genome research is needed as the foundation for an entirely new level of efficiency and success in the application of genetics and breeding to crop plants and products from crop plants. Genetic improvements in crop plants beyond current capabilities are needed to meet the growing world demand not only for more food, but also a greater diversity of food, higher-quality food, and safer food, produced on less land, while conserving soil, water, and genetic resources. Plant biology research, which is poised for dramatic advances, also depends fundamentally on plant genome research. The current Arabidopsis Genome Project has proved of immediate value to plant biology research, but a much greater effort is needed to ensure the full benefits of plant biology and especially plant genome research to agriculture. International cooperation is critical, both because genome projects are too large for any one country and the information forthcoming is of benefit to the world and not just the countries that do the work. Recent research on grass genomes has revealed that, because of extensive senteny and colinearity within linkage groups that make up the chromosomes, new information on the genome of one grass can be used to understand the genomes and predict the location of genes on chromosomes of the other grasses. Genome research applied to grasses as a group thereby can increase the efficiency and effectiveness of breeding for improvement of each member of this group, which includes wheat, corn, and rice, the world's three most important sources of food.

Co-ordination of signalling elements in guard cell ion channel control

Fine regulation of solutes transport across the guard cell plasma membrane for osmotic modulation is essential for the maintenance of the proper stomatal aperture in response to environmental stimuli. The major osmotica, K + , Cl - and malate are transported through selective ion channels in the plasma membrane and tonoplast of guard cells. To date, a number of ion channels have been shown to operate in the guard cell plasma membrane: outwardly- and inwardly-rectifying K + channels (I K,in and I K,out ), slowly- and rapid-activating anion channels, and stretch-activated non-selective channels. Slow and fast vacuolar channels (SV and FV) and voltage-independent K + -selective (VK) channels have been found at the guard cell tonoplast. On the molecular level, the regulation of the stomatal aperture is achieved by precise spatial and temporal co-ordination of channel activities through a network of signalling cascades that can be triggered, among others, by plant hormones. ABA and auxin as regulators of stomatal aperture have received most attention to date. It is clear now that the effect of these hormones on ion channels is mediated by second messengers pH i and [Ca 2+ ] i . The effect of ABA is generally associated with increases in pH i , while auxin acidifies the cytosol. Both of these hormones may induce elevation in [Ca 2+ ] i . Phosphorylation is another important factor in cellular signalling. The ABI1 gene encoding a 2C-type protein phosphatase has been shown to be a key element of ABA-dependent cascades. Plasma membrane voltage is also an important component of signalling and channel control, and has recently been shown to influence cytosolic-free [Ca 2+ ]. Thus, transduction of these, and associated cytoplasmic signals is clearly non-linear, and is probably important for providing a plasticity of cellular response to external and environmental stimuli. Understanding the interdependence and hierarchy of signalling elements now presents a major challenge for research in plant biology.

On Phylogeny of the Polytrichales

On Phylogeny of the Polytrichales

Future research in plant biology in space: summary of critical issues and recommendations of the workshop.

As stated in the "Introduction" of the present supple ment of Planta the workshop on "Plant Biology in Space" had to deal with three main tasks which are: firstly, to review international research progress in plant biology with special regard to the results obtained from space experiments; secondly, to define the critical questions for future research in space plant biology; and thirdly, to determine the relative importance of these questions. The first of these tasks may be fulfilled by the review papers published in this supplement. They clearly indicate that research under space conditions has significantly contributed to the recent progress in the field, with one of the best examples being the new concept for the perception of gravity by plants devel oped by Sievers and coworkers, mainly from results of space experiments. However, in spite of these fascinating new results, many questions still remain unanswered. The workshop was planned to identify these open questions and if possible to set priorities. Partly, these questions have already been embedded in the various review papers and in the two general discussion sessions printed in this supplement. The present contribution therefore attempts to summarize the final discussion session dedicated to the identification of the critical issues by also taking into account the various aspects already assessed in the review papers. Critical issues and questions for future research were defined mainly for three different domains, general issues for performing research on plants in space, issues con cerning perception of gravity in plants, and issues concerning responses of plants to gravity.

Plant Molecular Biology in Mexico

OverviewPlant molecular biology researchin Mexico is concentratedin two insti-tutions: CINVESTAV (Center for Research and Advanced Studies) andUNAM (Mexico’s National University). Plant biology research at CIN-VESTAV is carried out at its Irapuato Unit. The primary UNAM groupsare located at Cuernavaca (Biotechnology Institute, Nitrogen FixationResearchCenter) andMexicoCity (Facultadde Qu´imica). Other institu-tions that carry outplant biologyresearchincludetheCenter of Scientif-ic Research of Yucatan (CICY), University of Michoacan, Postgraduate´College, and CIMMYT. The state universities of Aguascalientes andPuebla are currently establishing research groups in plant biology. Sim-ilarly, the National Institute for Research in Agronomy, Forestry andLivestock (INIFAP) is creating a biotechnology group. With the excep-tion ofCIMMYT andINIFAP, allinstitutions offergraduateprogramsinthe different aspects of plant sciences. A brief description of represent-ative research lines in the two main centers of plant molecular biologyis as follows:CINVESTAVIrapuato UnitThe Irapuato Unit of CINVESTAV was created in 1981 to carry outresearch in plant biotechnology. However, the work actually started

DNA profiling techniques for plant variety identification

The unambiguous identification of plant varieties is important in many areas of agriculture and plant biology research. New techniques based on DNA profiling provide novel approaches to varietal identification which offer advantages over traditional morphological comparisons. These advantages include great potential resolving power, data that can be analysed objectively, testing at all stages of development, and cost effectiveness. In this review, the advantages of recently introduced polymerase chain reaction (PCR) based methods are compared with the well-established restriction fragment length polymorphism technique. Two approaches to PCR-based DNA profiling (random amplification of polymorphic DNA, sequence-tagged sites analysis) are compared and contrasted, and statistical methods for the analysis of data are described. The potential use of these techniques for Plant Breeders Rights registration in Australia is outlined.

In Vivo Pulse Labeling of Proteins in Attached Leaves with Radioactive Amino Acids

The pulse labeling of proteins in attached leaves by the incorporation of radioactive amino acids can be a valuable approach to study a wide range of topics pertaning to plant gene expression. Transient changes in the rate of net protein synthesis can be measured since pulse labeling permits discrimination between proteins actively synthesized during the labeling interval from those accumulated at earlier times. Specific procedures for a rapid and convenient method of in vivo pulse labeling are outlined which we believe could be broadly useful in plant biological research. A particularly important technical feature of the protocol is electroblotting of radioactive proteins from the sodium dodecyl sulfate acrylamide resolving gel matrix to polyvinylidene di-fluoride transfer membrane. This step permits a single polyacrylamide slab gel to be used for autoradiography, immunoblot analysis, and protein staining, thereby greatly facilitating comparison among these complementary techniques and resulting in a significant savings in time and radioactive sample. Central considerations concerning the quantitation and interpretation of in vivo pulse labeling data are discussed.

Routine cryofixation of plant tissue by propane jet freezing for freeze substitution

Cryofixation and freeze substitution methods were developed for ultrastructural studies of cells in complex plant tissues. Leaf tissues and root tips of tobacco (Nicotiana tabacum L. var. Maryland Mammoth) were frozen with a RMC MF7200 propane jet freezer and freeze substituted sequentially with tannic acid and osmium tetroxide/uranyl acetate in acetone. High quality preservation was consistently obtained for epidermal and phloem cells of the leaf, and epidermal, cortical, meristematic, and cap cells of the root tip. Leaf mesophyll cells were also often well frozen. Organelles, including nuclei, endoplasmic reticulum, mitochondria, Golgi bodies, and plastids, showed excellent structural integrity and contrast. Most notable is the superior preservation of the cytoskeleton. Our results demonstrate that the propane jet freezer can be used routinely for high quality cryofixation of higher plant cells in certain complex tissues. This could have important implications for the use of cryofixation approach in a wide range of research in plant biology.

Imperial Bureau of Pastures and Field Crops

As a result of a recommendation of the 1946 Review Conference of the Imperial Agricultural Bureaux, the Imperial Bureau of Pastures and Forage Crops now becomes the Imperial Bureau of Pastures and Field Crops (director, Dr. R. O. Whyte). In its expanded form it will cover that part of the literature on the following crops not already the concern of the Bureaux of Plant Breeding and Genetics, or Soil Science: all cereals, field root-crops, pulses, groundnuts, cotton and other fibre crops grown on a field scale, sugar beet and sugar cane, in addition to the literature on grassland management and fodder production which has been the concern of the Bureau for the past seventeen years. Attention will continue to be given to those aspects of plant biological research which refer to the crops now covered, and sections will now also deal with farming systems concerned in the production of field or forage crops, and certain economic aspects of crop and fodder production.