Journal Covers
The Covers displayed in this section complement articles published in a variety of scientific journals which were conducted, in part or completely, in the MNIF. These covers are chosen by each journal's editorial staff as representing current, exciting research.
Cover Illustration: Micrograph with polarized light showing a portion of a cleared leaf of Uncaria acida (Rubiaceae). Four mesophyll crystal idioblasts are evident, each with two forms of crystal aggregates of calcium oxalate--crystal sand, and a single embedded spherical druse. The occurrence of two crystal forms in a single crystal idioblast is rare among plants, but it is a common feature in the majority of the subtribes in the Naucleeae (Rubiaceae). The presence of two crystal forms in one cell raises a variety of questions about their genetic control and possible function. Other visible objects are large birefringent tracheary elements with scalariform secondary wall thickenings, and smaller fragments of mesophyll primary cell walls (3,158x). See Lersten and Horner--Unique calcium oxalate "duplex" and "concretion" idioblasts in leaves of tribe Naucleeae (Rubiaceae) on pp. 1-11 in this issue. Photo credit: N. R. Lersten and H. T. Horner.
Wang, J, and Z Lin. 2010. Dye-sensitized TiO2 nanotube solar cells with markedly enhanced performance via rational surface engineering. Chemistry of Materials 22: 579-584.
COVER Viewed from the inside of a fractured rice leaf, cells of the rice pathogenic bacterium Xanthomonas oryzae pv. oryzicola invade through a stoma. Xanthomonas species inject host cells with unusual DNA binding proteins called transcription activator-like (TAL) effectors to up-regulate genes important for infection. Two studies in this issue (pages 1501 and 1509; related Perspective, page 1491) decipher TAL effector target specificity and show that now specificities can be engineered. Image: Adam Bogdanove and Harry Horner/Iowa State University; false color: Yael Kats/Science
Moscou, Mathew J, and Adam J. Bogdanove. 2009. A simple cipher governs DNA recognition by TAL effectors. Science 326: 1501.
On the Cover The leaf anatomy of Peperomia species is characterized by a multilayered upper hypodermis subtended by a typically single-layered photosynthetic palisade parenchyma. This latter layer consistently contains spherical aggregates of crystals of calcium oxalate called druses. The presence of these layer-specific druses is a taxonomic characteristic of the genus. A survey of representative species, based on molecular data, shows that these druses may occur in almost every palisade cell, may be relatively larger in palisade cells over the veins and smaller in palisade cells of the areoles, or may occur only in the palisade cells over the veins, as shown in this image of Peperomia marmorata. These crystal macropatterns are of phylogenetic importance and may be involved with leaf physiology and envirnonmental conditions. The light microscope image was digitally captured by Harry T. Horner using a bleached leaf clearing viewed between crossed polarizers.
Horner, HT, S Wanke and M-S Samain. 2009. Evolution and systematic value of leaf crystal macropatterns in the Genus Peperomia (Piperacease). International Journal of Plant Sciences 170: 343-354.
Wang, J, J Xu, M Goodman, Y Chen, M Cai, J Shinar and Z Lin. 2008. A simple biphasic route to water soluble dithiocarbamate functionalized quantum dots. Journal of Materials Chemistry 18: 3270-3274.
Wang X, HT Horner, SL Krebs, R Arora. 2008. Structural adaptations in overwintering leaves of thermonastic and nonthermonastic Rhododendron species. Journal of American Society for Horticulture Science. 133:768-776.
Horner, HT, RA Healy, G Ren, D Fritz, A Klyne, C Seames, and RW
Thornburg. 2007. Amyloplast to chromoplast conversion provides
nectar and protection in developing tobacco floral nectaries.
American Journal of Botany, 94:12-24.
Lersten, NR, and HT Horner. 2005. Development of the calcium
oxalate crystal macropattern in pomegranate (Punica granatum,
Punicaceae). American Journal of Botany 92:1935-1941.
Healy, RA, HT Horner, TB Bailey, and RG Palmer. 2005. A microscopic
study of the trichomes on gynoecia of normal and tretraploid Clark
cultivars of Glycine max and seven near isogenic lines.
International Journal of Plant Sciences 16(3):415-425.
Lersten, NR, and HT Horner. 2005. Macropattern of styloid and druse
crystals in Quillaja (Quillajaceae) bark and leaves. International
Journal of Plant Sciences 166:705-711.
Applequist, WL, R Cronn and JF Wendel. 2001. Comparative
development of fiber in wild and cultivated cotton. Evolution &
Development 3: 3-17
Liu F, X Cui, HT Horner, H Weiner and PS Schnable. 2001.
Mitochondrial aldehyde dehydrogenase activity is required for male
fertility in maize. Plant Cell 13 (5): 1063-1078
Boughton AJ, RL Harrison, LC Lewis and BC Bonning. 1999.
Characterization of a nucleopolyhedrovirus from the black cutworm,
Agrotis ipsilon (Lepidoptera: Noctuidae). Journal of Invertebrate
Pathology 74 (3): 289-294.
Pepper T. 1999. Front Cover Image, Second Prize, Just for Fun
Micrograph Contest M&M '99 in Portland, OR "Y2K" 'If only the
millennium bugs were so easy to detect! These net-winged midge
larvae (Horaia) from Nepal seem happy to munch the circuit pathways
towards the year 2000. Just wait until spring when they'll become
trout bait.' Microscopy Today
Hu W-J, SA Harding, J Lung, JL Popko, J Ralph, DD Stokke, C-J Tsai,
and V Chiang. 1999. Repression of lignin biosynthesis promotes
cellulose accumulation and growth in transgenic trees. Nature
Biotechnology 17 (8): 808-812.
Anderson MC, P Che, J Song, BJ Nikolau and ES Wurtele. 1998.
3-methylcrotonyl-coenzyme A carboxylase is a component of the
mitochondrial leucine catabolic pathway in plants. Plant Physiology
118 (12): 1127-1138.
Perdomo A, and JS Burris. 1998. Histochemical, physiological, and
ultrastructural changes in the maize embryo during artificial
drying. Crop Science 138 (5): 1236-1244.
Foster, CM, HT Horner and WR Graves. 1998. Nodulation response of
woody papilionoid species after inoculation with rhizobia and soil
from Hawaii, Asia, and North America. Plant and Soil 205:103-111.
Wetzel CM, C-Z Jiang, LJ Meehan, DF Voytas and SR Rodermel. 1994.
Nuclear-organelle interactions: the immutans variegation mutant of
Arabidopsis is plastid autonomous and impaired in carotenoid
biosynthesis. The Plant Journal 6: 161-175.
Horner HT, and BL Wagner. 1992. Association of four different
calcium crystals in the anther connective tissue and hypodermal
stomium of Capsicum annuum (Solanaceae) during microsporogenesis.
American Journal of Botany 79 (5): 531-541.
