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Important Characters (important + character)
Selected AbstractsEffect of Plant Factors, Sugar Contents, and Control Methods on the Top Borer (Scirpophaga nivella F.) Infestation in Selected Varieties of SugarcaneENTOMOLOGICAL RESEARCH, Issue 3 2005Abdul KHALIQ ABSTRACT Sugarcane (Saccharum officinarum L.) varieties CP-43/33 and L-118 susceptible, BF-162 and SPSG-26 resistant while CP-72/2086 as intermediate were screened for studies on top borer, Scirpophaga nivella Fabricus (Pyralidae: Lepidoptera). Morpho-physio chemical plant factors as well as quality of sugar were examined to elucidate the relationship between pest infestations. The observations on leaf thickness 0.735* and moisture contents 0.771* showed positive and significant correlation with the pest infestation at tillering stage. Total minerals, manganese and copper contents did not show significant correlation with the pest infestation, whereas nitrogen, potassium, calcium, magnesium and ferrous contents manifested positive and significant correlation with the pest infestation. Phosphorous, carbohydrates, fats and zinc produced significant and adverse effect on the pest infestation at tillering stage. Zinc contents with contrasting behaviors appeared to be the most important character with co-efficient value of 0.764 followed by ferrous with positive sign. The effect of borer infestation was significantly negative on pol (sucrose), Brix contents (total soluble solids), and CCS (commercial cane sugar). The coefficient of determination value was 0.821, obtained by computing fiber content, pol, Brix and CCS factors together for multivariate regression models. Application of trash mulching at the time of sowing proved to be the most effective treatment with minimum infestation (3.91%) of borer and maximum protection level (62.87%) followed by Furadan®, removal of dead hearts + spike thrust, hand collection of egg masses, and cutting of shoots at 15 days interval. [source] Development of the pharyngeal arch skeleton in Catostomus commersonii (Teleostei: Cypriniformes)JOURNAL OF MORPHOLOGY, Issue 3 2009Jeffrey M. Engeman Abstract Skeletal elements of the gill arches of adult cypriniform fishes vary widely in number, size, and shape and are important characters in morphologically based phylogenetic studies. Understanding the developmental basis for this variation is thus phylogenetically significant but also important in relation to the many developmental genetic and molecularly based studies of the early developing and hence experimentally tractable gill arches in the zebrafish, a cyprinid cypriniform. We describe the sequence of the chondrification and ossification of the pharyngeal arches and associated dermal bones from Catostomus commersonii (Catostomidae, Cypriniformes) and make selected comparisons to other similarly described pharyngeal arches. We noted shared spatial trends in arch development including the formation of ventral cartilages before dorsal and anterior cartilages before posterior. Qualitatively variable gill arch elements in Cypriniformes including pharyngobranchial 1, pharyngobranchial 4, and the sublingual are the last such elements to chondrify in C. commersonii. We show that the sublingual bone in C. commersonii has two cartilaginous precursors that fuse and ossify to form the single bone in adults. This indicates homology of the sublingual in catostomids to the two sublingual bones in the adults of cobitids and balitorids. Intriguing patterns of fusion and segmentation of the cartilages in the pharyngeal arches were discovered. These include the individuation of the basihyal and anterior copula through segmentation of a single cartilage rod, fusion of cartilaginous basibranchials 4 and 5, and fusion of hypobranchial 4 with ceratobranchial 4. Such "fluidity" in cartilage patterning may be widespread in fishes and requires further comparative developmental studies. J. Morphol., 2009. © 2008 Wiley-Liss, Inc. [source] 95 Development of macroalgal (seaweed) taxonomic keys utilizing digital & media technologyJOURNAL OF PHYCOLOGY, Issue 2003R. L. Lehman Digital, user-friendly seaweed identification keys and instructional materials can provide information that allows students and researchers to enhance and improve marine field and ecological studies by including macroalgae. In much of the scientific literature, the seaweeds are only characterized to division (red, green, and brown), sometimes to genus, and very rarely to species; so there is clearly a need for a reference that facilitates the identification of the seaweeds. Many of the problems occur because of the lack of user-friendly identification keys. However, it is not necessary to be an expert to identify seaweeds as many of the key characteristics used in their identification can be ascertained with the naked eye, a hand lens and an inexpensive microscope. What is needed is an identification guide that uses and displays important characters and identification structures visually (both macroscopic and microscopic) so that research scientists, students, teachers and the general public will be able to identify the seaweeds with confidence. We are using Lucid Professional software to construct digital keys for the identification of macroalgae from the Texas Coastal Bend. The advantages include: 1) key characters along with descriptions and images for specific macroalgae may be chosen from a geographic area of choice, 2) the user may evaluate the characters in any order and difficult or uncertain characters may be ignored, 3) descriptive pages of images, definitions, video clips and illustrations may be included for each taxon, and 4) the key can be displayed as a website or packaged as a CD to be used with laptop computers in the field. [source] Multivariate analysis of morphological variation among closely related species Bromus japonicus, B. squarrosus and B. arvensis (Poaceae) in comparison with isozyme evidencesNORDIC JOURNAL OF BOTANY, Issue 6 2004Tatjana Oja Morphological variation and taxonomic continuum of 110 specimens of Bromus arvensis, B. japonicus and B. squarrosus were analysed to assess the morphological variability of these close taxa. The importance of every morphological character was estimated by the GLM procedure. Stepwise discriminant analysis was used in order to find a set of morphological characters that maximises differences among the species. According to this, the most important characters appeared to be the length of anthers, width of lemma and lemma margin angle shape. The most important characters for the determination of Bromus arvensis was the length of anthers and for B. squarrosus width of lemma. According to the UPGMA cluster analysis, canonical discriminant, classificatory discriminant and principal component analyses, all specimens were separated into three moderately distinct groups which corresponded to the three traditional species. The study showed that qualitative characters were the best for the delimitation of the tax a by statistical analyses and demonstrated the incongruity between the pattern of morphological and genetic (allozyme) variation among the three Bromus species. [source] ON PENTAMPLEXUSSCHINDEWOLF, 1940 (ANTHOZOA, RUGOSA) AND ITS POSSIBLE RELATIVES AND ANALOGUESPALAEONTOLOGY, Issue 2 2009JERZY FEDOROWSKI Abstract:, Three ampleximorphic taxa are revised and their most important characters are discussed in terms of possible or apparent relationships. Re-interpretation of its early ontogeny allows the assignment of Pentamplexus Schindewolf, 1940 to the family Polycoeliidae de Fromentel, 1861. Stereolasma variabilisVojnovsky-Krieger, 1934 is established as the type species of Vojnovskytes gen. nov. It resembles the family Polycoeliidae in some characters and the Antiphyllidae Ilina, 1970 or the Laccophyllidae Grabau, 1928 in others. Thus, its family status is not established. Revision of the type material of Fasciculophyllum tripusSchindewolf, 1952 allows its inclusion within the new genus Silesamplus, probably related to the family Laccophyllidae Grabau, 1928. Amplexoid morphology is further shown to be inadequate for the establishment of relationships on the family or subfamily level. Early ontogeny is most important in that respect, but biform vs normal morphology in the tabularium and free vs contratingent development of minor septa must also be considered, where appropriate. [source] Prospects for molecular breeding of barleyANNALS OF APPLIED BIOLOGY, Issue 1 2003W T B THOMAS Summary Data from UK Recommended List Trials showed that the introduction of new cultivars of spring and winter barley has maintained a significant increase in yield over time, whereas there has been no significant improvement in hot water extract, the major determinant of good malting quality, in either crop. Commercial barley breeding is based upon phenotypic selection, and the introduction of molecular breeding methods must either increase the rate of advance, or offer an improvement in the cost-effectiveness of breeding programmes. Molecular breeding can be applied to either single gene or polygenic characters but is not widely used in commercial barley breeding, other than as a marker for resistance to the Barley Yellow Mosaic Virus complex. There are many reports of potential targets for use in molecular breeding but the few validation studies that have been carried out to date are disappointing. Results from genomics studies are likely to lead to the identification of key candidate genes, which can be associated with economically important characters through co-location on certain chromosomal regions. Associations between candidate gene sequence haplotypes and phenotypic characteristics is expected to identify allelic combinations, which are most frequently observed in successful cultivars, that can be used in molecular breeding of barley on a commercial scale. [source] | ||||||||||