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Full-Text Articles in Life Sciences
Genotypic And Chemical Influences On Fruit Growth Of Tomato, Henry R. Owen, Louis H. Aung
Genotypic And Chemical Influences On Fruit Growth Of Tomato, Henry R. Owen, Louis H. Aung
Henry R. Owen
A relationship between ovary size at anthesis and final fruit diameter of 12 tomato (Lycopersicon esculentum Mill.) cultivars with a range of fruit sizes, shapes, and maturation rates was determined. ‘Fireball’, ‘Michigan/Ohio Hybrid’, and ‘New Yorker’ produced nonfasciated, spherical fruits of intermediate maturation rate and showed a significantly higher correlation between ovary diameter at anthesis and final fruit diameter than ‘Small Fry’, ‘Roma VF’, ‘Early Cascade’, ‘Campbell 1327’, or ‘Ponderosa’. A linear regression of final fruit diameter at maturity on ovary diameter at anthesis of the cultivars was highly significant (r2 = 0.92**; ÿ = 22.5X - 0.3). Continuous root …
Food Quality, Heterozygosity, And Fitness Correlates In Peromyscus Polionotus, James M. Novak, William R. Teska, Michael H.. Smith
Food Quality, Heterozygosity, And Fitness Correlates In Peromyscus Polionotus, James M. Novak, William R. Teska, Michael H.. Smith
James M. Novak
Oldfield mice (Peromyscus polionotus) that are more heterozygous utilize food and maintain body weight under varying degrees of dietary stress better than their less heterozygous counterparts. Mice were collected in southern Florida and fed diets of three qualities. During each dietary treatment, body weight, amount of food eaten, amount of food absorbed, and feeding efficiency were determined. Body weights for all mice decreased during the experiment. More heterozygous mice maintained their weight better during periods of dietary stress than those that were less heterozygous. Mice with different levels of genetic variability had essentially the same mean feeding efficiency with high …
Morphological Asymmetry And Interspecific Hybridization: A Case Study Using Hylid Frogs, Trip Lamb, James M. Novak, Diane L. Mahoney
Morphological Asymmetry And Interspecific Hybridization: A Case Study Using Hylid Frogs, Trip Lamb, James M. Novak, Diane L. Mahoney
James M. Novak
The limited studies addressing developmental stability of interspecific hybrids suggest a positive association between the level of fluctuating asymmetry and 1) the degree of divergence between parental species, and 2) the recency of the contact zone. To evaluate these associations, we examined asymmetry in a recentlyestablished hybrid population of treefrogs (Hyla cinerea and H. gratiosa) that show marked structural gene divergence. Fluctuating asymmetry (FA), directional asymmetry, and antisymmetry were assessed for eight paired osteometric traits in allozymically-defined parental and hybrid categories. FA levels varied considerably among traits. Nonetheless, for any given trait, the hybrid categories did not demonstrate elevated levels …
The Effect Of Selenium On Sulfur Uptake By Barley And Rice, Robert Mikkelsen, Hongfu Wan
The Effect Of Selenium On Sulfur Uptake By Barley And Rice, Robert Mikkelsen, Hongfu Wan
Robert Mikkelsen
Because of their chemical and physical similarities, plant uptake of sulfur and selenium are closely related. Barley and rice were grown in greenhouse solution culture to examine the synergistic interactions between sulfate and selenate in plant uptake. In the presence of low concentrations of solution sulfate, shoot and root yields were decreased with additions of selenate. However, when sulfate was present in elevated concentrations, no selenium-induced yield reductions occurred. A synergistic interaction between sulfate and selenate caused an increase in the shoot sulfur concentrations with increasing concentrations of selenate at low sulfate solution concentrations. At elevated sulfate concentrations, no synergism …
Biuret In Urea Fertilizer, Robert Mikkelsen
Biuret In Urea Fertilizer, Robert Mikkelsen
Robert Mikkelsen
Urea has become the leading form of N fertilizer worldwide. Historically there has been concern about biuret formed during the manufacturing of urea fertilizer and the potential adverse effect of biuret on plant growth. In this paper, the fate of biuret in soils and its phytotoxicity is reviewed. Biuret is mineralized by many soil micoorganisms, but the process is much slower than for urea. Excessively high biuret concentrations can damage seedlings and, like urea, should not be placed in close proximity to germinating seeds. Crop tolerance to biuret varies according to the plant species, soil conditions, fertilizer placement, and method …
Isoprenylation Is Required For The Processing Of The Lamin A Precursor, Michael Sinensky, L. A. Beck, T. J. Hosick
Isoprenylation Is Required For The Processing Of The Lamin A Precursor, Michael Sinensky, L. A. Beck, T. J. Hosick
Michael Sinensky
The nuclear lamina proteins, prelamin A, lamin B, and a 70-kD lamina-associated protein, are posttranslationally modified by a metabolite derived from mevalonate. This modification can be inhibited by treatment with (3-R,S)-3-fluoromevalonate, demonstrating that it is isoprenoid in nature. We have examined the association between isoprenoid metabolism and processing of the lamin A precursor in human and hamster cells. Inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase by mevinolin (lovastatin) specifically depletes endogenous isoprenoid pools and inhibits the conversion of prelamin A to lamin A. Prelamin A processing is also blocked by mevalonate starvation of Mev-1, a CHO cell line auxotrophic for mevalonate. …