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61.
Francisco G. Bittara Gary A. Secor Neil C. Gudmestad 《American Journal of Potato Research》2017,94(2):129-147
The effect of chloropicrin fumigation on the soil populations of Spongospora subterranea and the development of powdery scab, formation of root galls and tuber yield was investigated in seven field trials conducted in Minnesota and North Dakota. Sixteen potato cultivars, with different levels of susceptibility to disease on roots and tubers, were planted in plots treated with chloropicrin at rates ranging from zero to 201.8 kg a.i. ha?1. The amount of S. subterranea DNA in soil was determined using qPCR. Bioassays were conducted to further assess the effect of chloropicrin fumigation on root colonization by S. subterranea in two potato cultivars with contrasting disease susceptibility. In the field, chloropicrin applied at rates between 70.1 to 201.8 kg a.i. ha?1 significantly decreased S. subterranea initial inoculum in soil but increased the amount of disease observed on roots and tubers of susceptible cultivars. The effect of increasing disease was confirmed in controlled conditions experiments. Although the amount of S. subterranea DNA in roots of bioassay plants increased with increasing chloropicrin rates, it remained similar among potato cultivars. Chloropicrin fumigation significantly increased tuber yield which in cultivars such as Shepody and Umatilla Russet were associated with the amount root galls (r = 0.30; P < 0.03). Results of these studies contradict earlier reports on the use of chloropicrin fumigation for the control of powdery scab. Factors other than inoculum level, such as environmental conditions that affect inoculum efficiency and host susceptibility, may be significant contributors to the development of powdery scab and root gall formation. 相似文献
62.
Jégou S Douliez JP Mollé D Boivin P Marion D 《Journal of agricultural and food chemistry》2001,49(10):4942-4949
The influence of malting and brewing processes on the chemical and structural modifications occurring on LTP1 was investigated by mass spectrometry and circular dichroism. Proteins were first purified from malt, and samples were collected at various steps of beer processing performed on two barley cultivars. The levels of LTP1 found in malt were not significantly different from the amounts in barley seed. However, in malt, both LTP1b, a post-translational form of LTP1, and a third isoform named LTP1c were isolated. Moreover, both of these proteins were found to be heterogeneously glycated but still exhibited an alpha-helix structure. Both glycated LTP1 and LTP1b were recovered during mashing. It was also shown that glycated LTP1 was unfolded during heat treatment of wort boiling, which is in agreement with the denatured form previously isolated from beer. 相似文献
63.
Characterization of the LH peak after short and long fixed‐time artificial insemination protocols in sheep raised in the tropics 下载免费PDF全文
Gabriela Azenha Milani Soriano Felipe Rydygier de Ruediger Marilice Zundt Marco Aurélio da Cruz Nobre Gomes Lilian Francisco Arantes de Souza Ines Cristina Giometti Guilherme de Paula Nogueira Gustavo Ricci Zanelli Fabiola Cristiane de Almeida Rego Caliê Castilho 《Animal Science Journal》2018,89(9):1245-1252
The aim of this study was to evaluate the peak in luteinizing hormone (LH) and the pregnancy rate of sheep (Texel × Santa Inês) in the tropics using short‐ (6 days) and long‐term (12 days) progesterone protocols followed by artificial insemination (AI) both in and out of the breeding season. Experiment 1 was conducted within (IN) the breeding season (autumn, n = 36), and experiment 2 was conducted outside (OUT) of the breeding season (spring, n = 43). In each experiment, the sheep were divided into two groups (6 or 12 days) according to the duration of treatment with a single‐use progesterone release vaginal device (CIDR®, Pfizer, São Paulo, SP, Brazil), and blood samples were collected from 10 animals per group every 4 hr to measure the LH and progesterone concentrations. In the spring, the characteristics of the LH peak did not differ between groups; but in the autumn, there were differences between groups at the beginning (G‐6 IN: 36.44 ± 5.46 hr; G‐12 IN: 26.57 ± 4.99 hr) and end of the LH peak (G‐6 IN: 46.22 ± 7.51 hr; G‐12 IN: 34.86 ± 8.86 hr). The results showed alterations in the LH peak during the breeding season only in the sheep undergoing the short‐term protocol. 相似文献
64.
Côté AP Benin AI Ockwig NW O'Keeffe M Matzger AJ Yaghi OM 《Science (New York, N.Y.)》2005,310(5751):1166-1170
Covalent organic frameworks (COFs) have been designed and successfully synthesized by condensation reactions of phenyl diboronic acid {C6H4[B(OH)2]2} and hexahydroxytriphenylene [C18H6(OH)6]. Powder x-ray diffraction studies of the highly crystalline products (C3H2BO)6.(C9H12)1 (COF-1) and C9H4BO2 (COF-5) revealed expanded porous graphitic layers that are either staggered (COF-1, P6(3)/mmc) or eclipsed (COF-5, P6/mmm). Their crystal structures are entirely held by strong bonds between B, C, and O atoms to form rigid porous architectures with pore sizes ranging from 7 to 27 angstroms. COF-1 and COF-5 exhibit high thermal stability (to temperatures up to 500 degrees to 600 degrees C), permanent porosity, and high surface areas (711 and 1590 square meters per gram, respectively). 相似文献
65.
Neto JO Azevedo SS Gennari SM Funada MR Pena HF Araújo AR Batista CS Silva ML Gomes AA Piatti RM Alves CJ 《Veterinary parasitology》2008,156(3-4):329-332
The prevalence and risk factors for anti-Toxoplasma gondii antibodies were investigated in goats of the Seridó Oriental microregion, Rio Grande do Norte state, Northeast region of Brazil. Three hundred and sixty-six blood samples from goats collected by jugular venopuncture were used. For the serologic diagnosis of Toxoplasma gondii infection, the indirect fluorescent-antibody test (IFAT) with cut-off value 1:64 was carried out. The prevalence of anti-T. gondii antibodies was 30.6% [95% CI=25.9-35.6%] with titers ranging from 1:64 to 1:16,384. The multivariate logistic regression analysis showed that the risk factors associated to anti-T. gondii antibodies were presence of cats in the herd, extensive/semi-intensive management systems and lack of mineral supplementation. 相似文献
66.
67.
Vanesa García José M. Carral María Sáez-Royuela Rocío González Álvaro González 《Journal Of Applied Aquaculture》2013,25(1):57-65
There are no specifically formulated dry foods for tench (Tinca tinca L.), which forces farmers to use diets formulated for other fish species. This has major drawbacks, such as high mortality, slow growth, and body deformities. A 120 day experiment was performed with five-month-old juvenile tench (initial mean weight: 0.388 g; total length: 31.78 mm) to evaluate decapsulated Artemia cysts as a supplement to a dry diet for other fish species. Three treatments, differing in the daily supplement, were tested: 1,800 freshly hatched nauplii, 1,800 cysts, and 300 cysts per g of tench biomass. Final survival ranged between 95.3% and 97.9%. Juvenile tench that received the supplement of 1,800 decapsulated Artemia cysts had a specific growth rate (1.28), weight (1.83 g), and total length (52.30 mm) significantly higher than those with the same amount of nauplii. The lowest supplement (300 cysts/g of fish biomass) allowed significantly lower growth and higher condition coefficient (1.40) than the rest. Animals with body deformities (1.06%) were only recorded in the groups that received the lowest cyst supplement. Results showed Artemia cysts are a suitable dietary supplement for juvenile tench, being an advantageous alternative to live nauplii. 相似文献
68.
José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
69.
Vítor Gabriel Ambrosini Daniel José Rosa Alex Basso Marcelo Borghezan Rosete Pescador Alcione Miotto 《Journal of plant nutrition》2017,40(3):404-416
This study aimed to assess the effect of liming as an ameliorator of copper (Cu) toxicity in black oats (Avena strigosa Schreb.) grown in soil with a sandy texture. The treatments were soil supplementation with increasing doses of lime (0.0, 0.5 and 1.0 g kg?1) and two of Cu (0 and 50 mg kg?1). Pre-germinated black oat seeds were sown for 30 days in the soil, subsequently, the plant height, root and shoot dry mass and concentration of total chlorophyll, chlorophylls a and b, carotenoids and total soluble carbohydrates and starch were analyzed. The dose of 50 mg kg?1 soil Cu caused a toxic effect on black oat plant growth and development, affected the internal distribution of nutrients, decreased the leaf chlorophyll concentration and increased the leaf concentration of total soluble carbohydrates and starch. Increasing lime doses ameliorated the toxic effects of Cu. 相似文献
70.
Swan Specchi Giuseppe Lacava Marc-André d’Anjou Eric Zini Edoardo Auriemma 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(11):1187-1190
A 10-year-old spayed female dalmatian dog developed acute vomiting and abdominal pain. Ultrasound examination of the abdomen showed right hydronephrosis and proximal ureter dilation with mild retroperitoneal free fluid. Computed tomography (CT) of the abdomen confirmed the ultrasonographic findings and revealed, additionally, a right ureteral stone. Spontaneus rupture of the right ureter was confirmed with CT post ultrasound-guided percutaneous antegrade pyelography. Pyeloureteral rupture and the presence of a ureteral stone were confirmed at surgery. 相似文献