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A suite of commercially available volatile compounds was tested in an olfactometer bioassay for responses by the crucifer flea beetle (Phyllotreta cruciferae). Flea beetles were inhibited by exposure to hexane, pentane, and ethanol. Allyl-isothiocyanate, a crucifer-specific volatile, was moderately attractive to spring and early fall flea beetles, but inhibitory to late fall flea beetles. Spring flea beetles were most attracted to (+)-sabinene and E-β-ocimene, and 1-hexanol, 1-pentanol, and Z-3-hexen-1-ol were stronger attractants than allyl-isothiocyanate. Spring beetles were strongly inhibited by (-)-E-caryophyllene, β-ionone, indole, (±)-linalool, (+)-limonene, E-geraniol, and (-)-β-pinene and moderately inhibited by (-)-verbenene and hexenal. Our study showed that older leaves and flowers of Brassica napus variety AC Excel contained small amounts of β-ionone, but seedlings did not. β-lonone has not been documented previously in B. napus. [ABSTRACT FROM AUTHOR]

With the growing limitations on arable land, alfalfa (a widely cultivated, low-input forage) is now being selected to extend cultivation into saline lands for low-cost biofeedstock purposes. Here, minerals and transcriptome profiles were compared between two new salinity-tolerant North American alfalfa breeding populations and a more salinity-sensitive western Canadian alfalfa population grown under hydroponic saline conditions. All three populations accumulated two-fold higher sodium in roots than shoots as a function of increased electrical conductivity. At least 50% of differentially expressed genes (p < 0.05) were down-regulated in the salt-sensitive population growing under high salinity, while expression remained unchanged in the saline-tolerant populations. In particular, most reduction in transcript levels in the salt-sensitive population was observed in genes specifying cell wall structural components, lipids, secondary metabolism, auxin and ethylene hormones, development, transport, signalling, heat shock, proteolysis, pathogenesis-response, abiotic stress, RNA processing, and protein metabolism. Transcript diversity for transcription factors, protein modification, and protein degradation genes was also more strongly affected in salt-tolerant CW064027 than in salt-tolerant Bridgeview and salt-sensitive Rangelander, while both saline-tolerant populations showed more substantial up-regulation in redox-related genes and B-ZIP transcripts. The report highlights the first use of bulked genotypes as replicated samples to compare the transcriptomes of obligate out-cross breeding populations in alfalfa.

Dairy cattle eating fresh or ensiled alfalfa as the main portion of their diet often have low protein efficiency because of the rapid initial rate of ruminal protein degradation of fresh and ensiled alfalfa. Ruminal protein degradation of alfalfa might be reduced by introducing a gene that stimulates the accumulation of mono- or polymeric anthocyanidins in alfalfa. The objectives of this study were to fractionate protein and carbohydrates by in situ and chemical approaches, to evaluate in situ ruminal degradation characteristics and synchronization ratios, to determine protein availability to dairy cattle using the 2007 digestible intestinal protein/rumen-degraded protein balance (DVE/OEB) protein system, and to determine net energy for lactation using the Dutch net energy for lactation (VEM) system for 3 newly developed transgenic winter hardy anthocyanidin-accumulating T(1)Lc-alfalfa populations. These T(1)Lc-alfalfa populations, called (T1)BeavLc1, (T1)RambLc3, and (T1)RangLc4, had an average anthocyanidin accumulation of 163.4 μg/g of DM, whereas AC Grazeland (selected for a low initial rate of degradation) did not accumulate anthocyanidin. The basic chemical composition of the original samples, soluble and potentially degradable fractions, and degradation characteristics of crude protein and carbohydrates were similar in T(1)Lc-alfalfa and AC Grazeland. The undegradable in situ crude protein and neutral detergent fiber fraction had 1.3% lower CP and 4.8% lower CHO, respectively, in T(1)Lc-alfalfa compared with the amounts in AC Grazeland. The T(1)Lc-alfalfa had a 0.34 MJ/kg of DM higher calculated net energy for lactation and 1.9% of CP higher buffer soluble protein compared with that in AC Grazeland. By the protein evaluation model, it was predicted that T(1)Lc-alfalfa tended to have 11.9, 6.9, and 8.4 g/kg of DM higher rumen degradable protein, OEB, and intestinal available protein, respectively, compared with the amounts in AC Grazeland. The hourly OEB included an initial and substantial peak (oversupply) of protein relative to energy, which was highest in (T1)RangLc4 and lowest in (T1)RambLc3. The hourly OEB between 4 and 24h was similar and more balanced for all 4 alfalfa populations. In conclusion, T(1)Lc-alfalfa accumulated anthocyanidin, tended to have higher predicted intestinal protein availability, and had higher predicted net energy of lactation availability for dairy cattle than did AC Grazeland., (Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Modifications to the two-phase polymer gradient procedure for isolating plasma membrane from mammalian cells have resulted in greatly increased yields of purified plasma membrane. First, the cells were not treated with a membrane stabilizer (ZnCl2) prior to homogenization. This reduced the severity of homogenization required for disruption and allowed a greater proportion of the surface membrane to form large, flattened sheets that are more easily purified than the smaller fragments formed during more severe homogenization. Second, three crude fractions obtained from the homogenate (600g, 2000g, and 12,000g pellets), rather than a single, low-speed pellet (600g) containing only large sheets of membrane, were subjected to gradient centrifugation to obtain plasma membrane. This modification allowed purification of small as well as large fragments of plasmalemma and greatly increased the yield of purified membrane. Mg+2-dependent, Na+-K+-stimulated ATPase, a marker enzyme for plasma membrane, was enriched in the purified fraction by congruent to 17-fold relative to homogenate on a specific activity basis, and the yield of isolated plasma membrane averaged 70%, and was occasionally as high as 90%.

The genetic engineering of plants by DNA-mediated gene transfer requires that efficient transformation systems be developed. Considerable progress has been made in manipulating the Ti plasmid of Agrobacterium tumefaciens as a vehicle for delivery of foreign genes into protoplasts of dicotyle-donous plants. Part of the Ti plasmid, the T-DNA, can be incorporated into the genome of the host cell; the T-DNA can carry a foreign DNA sequence which co-integrates with it; under normal conditions, the tumorigenic-causing portion of the T-DNA can be inactivated so that transformed protoplasts can be regenerated and T-DNA with an inserted foreign gene can be stably maintained during regeneration, meiosis and gamete formation. A foreign gene has yet to be expressed in regenerated plants although a T-DNA gene for opine synthesis can function in regenerates. Developing a more ubiquitous transformation system for monocotyledons is further from fruition. Based on transformation systems for simple eukaryotic organisms, it is reasonable to expect that a DNA vector which is capable of amplifying a novel plant gene and which contains both a drug resistance marker to facilitate the selection of transformed plant protoplasts and a species-specific autonomously replicating sequence to ensure the stable maintenance of the input gene in the recipient cell can be constructed.

The ability of prolactin treatment to antagonize the luteolytic effect of prostaglandin F2 alpha (PGF2 alpha) was examined in the rat. Animals were superovulated, treated with PGF2 alpha and various doses of prolactin. Plasma progesterone concentrations were measured to assess luteal function. Microsomes were prepared from ovarian homogenates and examined by wide-angle x-ray diffraction for evidence of structural changes in the cellular membranes during luteolysis. In addition, the concentrations of various lipids were analyzed for alterations in membrane lipid composition. In preparations from control animals, all of the membrane lipid was in the liquid-crystalline phase at body temperature. However, in samples from PGF2 alpha-treated rats, portions of the bilayer underwent a structural alteration from liquid-crystalline to gel phase. This phase transition was not accompanied by significant changes in the relative concentrations of various lipids. Prolactin treatment was effective in inhibiting this membrane breakdown in a dose-dependent manner. These results suggest that PGF2 alpha and prolactin may control luteal function by affecting membrane structure.