“
“Switchgrass (Panicum virgatum L.), a perennial warm-season grass established by seed has been AZD8186 purchase recommended by

the US Department of Energy as a model herbaceous biofuel crop. Neoteric seeds may be dormant resulting in delayed and sporadic germination and emergence, jeopardizing establishment of a good plant stand. Switchgrass dormancy may be alleviated by mechanical or chemical scarification, stratification, and after-ripening, suggesting physical and/or physiological dormancy. The underlying mechanisms and physiology of dormancy in these seeds; however, are not well understood. This work investigates the physiology of switchgrass seed dormancy; first by identifying the contribution of the different switchgrass structures (glumes, lemma, palea, pericarp/testa, endosperm) on regulating germination, and then by testing specific mechanisms of coat-imposed dormancy. We sequentially removed structures of freshly harvested seeds of two upland (Cave-in-Rock, Trailblazer) and two lowland (Alamo, Kanlow) cultivars. The main structure inhibiting germination was the pericarp/testa, with the lemma and palea (bracts) having a secondary effect that differed by genotype. Seeds with glumes and bracts removed, and pericarp/testa cut with endosperm either attached or removed just above the embryo, resulted in high germination percentages and rate, indicating

no morphological dormancy, and no effect of the endosperm on germination. The lemma, palea, and pericarp/testa were neither a barrier for water uptake nor contained inhibitory compounds. By adjusting the oxygen concentration this website of the environment and the physical integrity of the covering structures, we found the enclosing structures acted as barriers to oxygen. Puncturing the pericarp/testa of seeds with glumes and bracts removed, enhanced germination at 1, 10,21 or 100% oxygen. Combined results showed that the structural integrity of the Sotrastaurin order pericarp/testa (primary) and lemma/palea (secondary) influenced germination, suggesting an important mechanical effect of these layers as barriers for

radicle protrusion. Therefore, a combination of seed-coat mechanisms regulates germination in switchgrass seeds. (C) 2013 Elsevier B.V. All rights reserved.”
“OBJECTIVES: Acute retinal necrosis is a rapidly progressive and devastating viral retinitis caused by the herpesvirus family. Systemic acyclovir is the treatment of choice; however, the progression of retinal lesions ceases approximately 2 days after treatment initiation. An intravitreal injection of acyclovir may be used an adjuvant therapy during the first 2 days of treatment when systemically administered acyclovir has not reached therapeutic levels in the retina. The aims of this study were to determine the pharmacokinetic profile of acyclovir in the rabbit vitreous after intravitreal injection and the functional effects of acyclovir in the rabbit retina.