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961.
Prakash R. Arelli Vergel C. Concibido Lawrence D. Young 《Journal of Crop Science and Biotechnology》2010,13(3):163-167
Worldwide, soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is the most destructive pathogen of soybean [Glycine max (L.) Merr.]. Crop losses are primarily mitigated by the use of resistant cultivars. Nematode populations are variable and
have adapted to reproduce on resistant cultivars over time because resistance primarily traces to two soybean accessions,
Plant Introduction (PI) 88788 and Peking. Soybean cultivar Hartwig, derived primarily from PI437654, was released for its
comprehensive resistance to most SCN populations. A synthetic nematode population (LY1) was recently selected for its reproduction
on Hartwig. The LY1 nematode population currently infects known sources of resistance except soybean PI567516C; however, the
resistance to LY1 has not been characterized. The objective of this study was to identify quantitative trait loci (QTLs) underlying
resistance to the LY1 SCN population in PI567516C, identify diagnostic DNA markers for the LY1 resistance, and confirm their
utility for marker-assisted selection (MAS). Resistant soybean line PI567516C was crossed to susceptible cultivar Hartwig
to generate 105 recombinant inbred lines (F2-derived F5 families). QTLs were mapped using simple sequence repeats (SSRs) covering 20 Linkage Groups (LGs) and three diagnostic markers,
Satt592, Satt331, and Sat_274, were identified on LG O. These markers have a combined efficacy of 90% in identifying resistant
lines in a second cross that has been generated by crossing a susceptible cultivar 5601T with resistant PI567516C. F2-derived F4 segregating population was used in MAS to identify resistant lines. 相似文献
962.
963.
Kyoung Hoon KIM Guang‐Lin JIN Young‐Kyoon OH Man‐Kang SONG 《Animal Science Journal》2010,81(3):331-337
Hanwoo (Korean native) steers (274.8 ± 4.6 kg) with ruminal and duodenal cannulae were used in a 4 × 4 Latin square design experiment to examine the effects of dietary treatments on starch disappearance in the gastrointestinal tract. Dietary treatments consisted of concentrate that were based on ground corn with soybean meal (C‐SBM), ground corn with corn gluten meal (C‐CGM), ground barley with soybean meal (B‐SBM) and ground barley with corn gluten meal (B‐CGM). Although the intakes of starch and protein for steers fed experimental diets were different, it did not change ruminal pH and total volatile fatty acid concentrations. Average duodenal CP flow and quantity of CP apparently digested post‐ruminally was higher (P = 0.001) for CGM‐based diets than SBM‐based diets. There were increases in quantity (P < 0.001) and percentage (P < 0.001) of corn starch digested post‐ruminally compared to barley starch. Synchronized diets showed higher percentages (P = 0.03) of starch apparently digested post‐ruminally than asynchronization. Hanwoo steers fed a corn‐based diet with a large quantity of starch reaching the duodenum and fed C‐CGM supplying great amounts of protein to the small intestine may have contributed to increased post‐ruminal starch digestion. 相似文献
964.
Field experiments were conducted to evaluate cover crop (none, winter wheat, or winter rye) and pre-emergence (PRE) applications of clomazone plus ethalfluralin alone or with halosulfuron [PRE or post-emergence (POST)] for smooth crabgrass [Digitaria ischaemum (Schreb. ex Schweig) Schreb. ex Muhl.] and redroot pigweed (Amaranthus retroflexus L.) control in no-tillage ‘Aspen’ jack-o-lantern pumpkin (Cucurbita pepo L.). At pumpkin harvest, cover crops had reduced smooth crabgrass density, but not redroot pigweed. Although PRE or POST applications of halosulfuron alone were more effective at reducing redroot pigweed density than clomazone plus ethalfluralin PRE, the combination of halosulfuron plus clomazone and ethalfluralin PRE reduced redroot pigweed density to the greatest extent. Pumpkin yields were not affected by cover crop, although average pumpkin sizes were greater with the inclusion of cover crop residues. Pumpkin fruit sizes and yields were the greatest with clomazone and ethalfluralin PRE in combination with halosulfuron applied PRE or POST. Overall, cover crop had relatively little influence on pumpkin yields compared with herbicide treatments. The addition of halosulfuron to clomazone and ethalfluralin provided greater broadleaf weed control resulting in greater jack-o-lantern pumpkin yields. 相似文献
965.
Kiyoon Kang Kyungjin Lee Atsushi Ishihara Sangkyu Park Young Soon Kim Kyoungwhan Back 《Scientia Horticulturae》2010
Caffeoylserotonin (CaS) is a serotonin derivative that belongs to the family of phenylpropanoid amides, but has not previously been identified in plants. In this study, pepper fruits challenged with the anthracnose fungus, Colletotrichum gloeosporioides, were found to synthesize CaS, which accumulated at concentrations of up to 2.3 μg/g fresh weight. The induction of CaS was accompanied by the upregulation of both 4-coumarate-CoA ligase (4CL) and serotonin N-hydroxycinnamoyl transferase (SHT) in unripe pepper fruits. However, no induction of SHT and 4CL was observed in ripe pepper fruits consistent with the lower level of CaS production. 相似文献
966.
967.
Improvement of the ventilation system of a naturally ventilated broiler house in the cold season using computational simulations 总被引:3,自引:0,他引:3
968.
Jenkins DM Teruel MA Reyes-de-Corcuera JI Young O 《Journal of agricultural and food chemistry》2008,56(18):8303-8308
An experiment is described in which a custom-made glucose electrode is used to directly monitor the enzymatic hydrolysis of lactose to glucose. The transient profile of beta- d-glucose can be used to simultaneously determine the rate constants for mutarotation and for enzymatic hydrolysis by applying a dynamic nonlinear regression routine. Due to differences in the mutarotation rate constants between lactose and glucose, the beta- d-glucose concentration "overshoots" equilibrium under certain conditions, which can be modeled mathematically. This overshoot can be observed reliably and used to quantify the differences in mutarotational equilibria between glucose and lactose. These observations may be important for the analysis of dairy products and commercial lactase preparations and illustrate an unusual kinetic phenomenon caused by intramolecular forces. This approach may also be important for the accurate determination of a variety of oligosaccharides such as glycogen, which tend to be composed primarily of one stereoisomer. 相似文献
969.
The protective effect of proanthocyanidins from persimmon peel, using both oligomers and polymers, was investigated in a db/db type 2 diabetes model. Male db/db mice were divided into three groups: control (vehicle), polymer-, or oligomer- (10 mg/(kg body weight x day x p.o.)) administered mice. Age-matched nondiabetic m/m mice were used as a normal group. The administration of proanthocyanidins reduced hyperglycemia in db/db mice through a decline in the serum level of glucose and glycosylated protein. In addition, it had a strong effect on hyperlipidemia through lowering levels of triglyceride, total cholesterol, and nonesterified fatty acids. The protective effect against hyperglycemia and hyperlipidemia was greater in the groups administered the oligomeric rather than polymeric form. The increased oxidative stress in db/db mice was attenuated by the administration of oligomers through inhibiting the generation of reactive oxygen species and lipid peroxidation and elevating the reduced glutathione/oxidized glutathione ratio. On the other hand, polymers did not show such an effect. Moreover, expressions in the liver of sterol regulatory element binding protein (SREBP)-1 and SREBP-2 were downregulated by the administration of proanthocyanidins, especially the oligomeric form. Oligomers caused a slight elevation in the expression of peroxisome proliferator-activated receptors alpha. Furthermore, oligomeric proanthocyanidin regulated the expression of nuclear factor kappaB in db/db type 2 diabetes via the activation of inhibitor protein kappaB-alpha. It also attenuated the protein expressions of cyclooxygenase-2 and inducible nitric oxide synthase. This suggests that oligomers would act as a regulator in inflammatory reactions associated with oxidative stress in type 2 diabetes. The present study results suggest that proanthocyanidin administration, especially the oligomeric form, may improve oxidative stress via the regulation of hyperlipidemia than hyperglycemia in type 2 diabetes. 相似文献
970.
Wei-An Lai P. D. Rekha A. B. Arun Chiu-Chung Young 《Biology and Fertility of Soils》2008,45(2):155-164
Benefits from the application of plant growth-promoting bacteria in agriculture largely depend on the complex interactions
between several factors including the nature of fertilizers selected. This study was designed to determine the fine tuning
between the inoculated bacteria and different fertilizers and their effect on the growth of lettuce plants (Lactuca sativa L.). Plant growth promotion by a novel species of the genus Azospirillum, namely A. rugosum IMMIB AFH-6, was tested by biochemical, bioassay, and greenhouse studies. The treatments used in the greenhouse study were;
unfertilized control (Blank), half recommended dose of chemical fertilizer (1/2CF), full recommended dose of chemical fertilizer
(1CF), pig manure fertilizer (PMF), pig manure fertilizer + half recommended dose of chemical fertilizer (PMF + 1/2CF), and
pig manure fertilizer + full recommended dose of chemical fertilizer (PMF + 1CF). All these treatments when inoculated with
A. rugosum IMMIB AFH-6 inoculation were, respectively, In-Blank, In-1/2CF, In-1CF, In-PMF, In-PMF + 1/2CF, and In-PMF + 1CF. Significant
increase in plant biomass and shoot N, P, Ca, and Fe was shown in the In-Blank treatment. Plant growth in soil amended with
PMF and A. rugosum IMMIB AFH-6 was significantly lower than in soil treated with the chemical fertilizer, but inoculation combined with chemical
fertilizer significantly elevated the plant biomass. The In-PMF + 1/2CF treatment showed the highest yield. A. rugosum IMMIB AFH-6 facilitated the accumulation of trace minerals in higher concentrations when PMF was combined with 1CF. To examine
the benefits of inoculation by A. rugosum IMMIB AFH-6, we have proposed a new type of data analysis which considers both biomass and nutrient content of plants. This
new type of analysis has shown the importance of the mineral content of plant. 相似文献