@article{pline_edmisten_oliver_wilcut_wells_allen_2002, title={Use of digital image analysis, viability stains, and germination assays to estimate conventional and glyphosate-resistant cotton pollen viability}, volume={42}, ISSN={["0011-183X"]}, DOI={10.2135/cropsci2002.2193}, abstractNote={Abstract Because the success of labor‐intensive hand crosses by breeders is dependent upon pollen viability, quick, simple, and inexpensive methods for viability assessment are of interest. Four such cotton pollen viability assays were compared to determine differences in viability estimates, and relative accuracy by correlation to seed set. The methods compared were Brewbaker & Kwack (B & K) medium, B & K medium plus aniline blue, a fluorochromatic reaction method (FCR), and Alexander's stain. Additionally, digital images of germinated pollen grains were analyzed by means of morphometry software to quantify pollen tube area per pollen grain, as a proposed additional method of assessing viability. Pollen from conventional, nontreated glyphosate‐resistant (GR) and glyphosate‐treated GR cotton ( Gossypium hirsutum L.) plants was tested by each method. Glyphosate treatments to GR cotton reduced pollen viability and corresponding seed set in all methods tested. Pollen germination measured by the B & K method was most closely related to seed set per boll, while Alexander's stain gave the highest estimates of viability. The FCR method indicated that many pollen grains from glyphosate‐treated GR cotton were irregularly shaped and only partially flourescein diacetate (FD) stained. All methods tested showed similar high correlation (0.7–0.8) of pollen viability to seed set. Morphometric analysis of digital images of germinated pollen found the greatest pollen tube area to pollen grain ratio with B & K medium + 30 m M sucrose. Because the B & K method most closely predicted the linear magnitude of seed set reduction to reduced pollen viability, allowed the use of morphometry software analysis, and was one of the simplest and least equipment‐demanding methods, it may provide broad utility for those assessing cotton pollen viability.}, number={6}, journal={CROP SCIENCE}, author={Pline, WA and Edmisten, KL and Oliver, T and Wilcut, JW and Wells, R and Allen, NS}, year={2002}, pages={2193–2200} }
 @article{pletjushkina_rajfur_pomorski_oliver_vasiliev_jacobson_2001, title={Induction of cortical oscillations in spreading cells by depolymerization of microtubules}, volume={48}, DOI={10.1002/cm.1012.abs}, abstractNote={Actomyosin-based cortical contractility is a common feature of eukaryotic cells but the capability to produce rhythmic contractions is found in only a few types such as cardiomyocytes. Mechanisms responsible for the acquisition of this capability remain largely unknown. Rhythmic contractility can be induced in non-muscle cells by microtubule depolymerization. Spreading epithelial cells and fibroblasts in which microtubules were depolymerized with nocodazole or colcemid underwent rhythmic oscillations of the body that lasted for several hours before the cells acquired a stable, flattened shape. By contrast, control cells spread and flattened into discoid shapes in a smooth and regular manner. Quantitative analysis of the oscillations showed that they have a period of about 50 seconds. The kinase inhibitors, HA 1077 and H7, and the more specific rho-kinase inhibitor, Y 27632, caused the oscillations to immediately cease and the cells to become flat. Transient increases in cytoplasmic calcium preceded the contractile phase of the oscillations. Wrinkle formation by cells plated on elastic substrata indicated that the contractility of colcemid-treated cells increased in comparison to controls but was drastically decreased after HA 1077 addition. These data suggest that an intact microtubular system normally prevents pulsations by moderating excessive rho-mediated actin myosin contractility. Possible mechanistic interactions between rho-mediated and calcium activated contractile pathways that could produce morphological oscillations are discussed. Cell Motil. Cytoskeleton 48:235–244, 2001. © 2001 Wiley-Liss, Inc.}, number={4}, journal={Cell Motility and the Cytoskeleton}, author={Pletjushkina, O. J. and Rajfur, Z. and Pomorski, P. and Oliver, T. N. and Vasiliev, J. M. and Jacobson, K. A.}, year={2001}, pages={235–244} }