印度西孟加拉邦德赖地区梨竹生长基质标准化、萌发种子尺寸和实生苗生长

2008年2-4月,在印度西孟加拉邦德赖地区开展了试验,该试验对6个生长基质和3个种子的重量进行了分析,以找出其对梨竹萌发和实生苗生长的影响。与其他基质相比,将50 g的种子种在土壤、沙土和FYM以同一比例混合的基质中,种子萌发较好,实生苗生长更好。     

In planta detection of Macrophomina phaseolina from jute (Corchorus olitorius) by a sodium acetate-based direct PCR method

Macrophomina phaseolina (Tassi) Goid. is the most important pathogen of jute and primarily causes seedling blight, leaf spot and stem rot. The pathogen was detected from field samples by a simple method of direct PCR (dPCR) which obviates the steps of DNA extraction. The leaf bits were treated with a lysis buffer at 65°C for 25 min, whereas the stem pieces were initially incubated at 65°C for 5 min followed by incubation at 60°C for 25 min and the lysate was used as PCR template. Based on the type of tissue, the composition and concentration of lysis buffer systems were optimized. For leaf samples the optimized buffer system composed of 20 mmol l ^-1 tris (hydroxymethyl aminomethane (Tris)-Cl (pH 8.0), 1.5 mmol l ^-1 ethylene diamine tetra acetate (EDTA) (pH 8.0), 1.4 mol l ^-1 sodium acetate and 200 μg/ml proteinase K. Further, 3% PVP (w/v) and β-mercaptoethanol (1% w/v) were added into the buffer. In case of stem samples, PVP was not applied and higher concentrations were used for other components. M. phaseolina could be detected from both leaf and stem samples generating amplicon of 350 bp. This is the first report of detecting M. phaseolina by a direct PCR method without DNA extraction.     

Chlorocholine chloride mediated resistance mechanism and protection against leaf spot disease of Stevia rebaudiana Bertoni

Investigations have been carried out to determine the influence of chlorocholine chloride on induction of the resistance mechanisms of Stevia rebaudiana against leaf spot disease, caused by Alternaria alternata. The paper also focuses an impact of chlorocholine chloride induced resistance on reduction of leaf spot disease. Chlorocholine chloride is attributed to its significant role in defence responses through augmentation of phenol and salicylic acid content as well as stimulation of phenylalanine ammonia lyase and peroxidase activity in S. rebaudiana following inoculation with A. alternata. Histochemical studies revealed that fungal invasion as well as infection process was appreciably reduced in chlorocholine chloride treated plants through peroxidase-H₂O₂ mediated strengthening of cell wall. The overall study highlights the significant role of chlorocholine chloride in induction of resistance in S. rebaudiana against A. alternata.     

Correlations among <Emphasis Type="Italic">Anaplasma marginale</Emphasis> parasitemia and markers of oxidative stress in crossbred calves

The present study was designed to determine the correlations among Anaplasma marginale parasitemia and markers of oxidative stress in crossbred calves. Blood was collected from 11 crossbred calves infected with A. marginale along with 11 healthy crossbred calves as controls for determination of hematology and oxidative stress indicators. Percentage of parasitemia in infected calves varied from 0.8% to 6.0%. The values of hematological indicators and antioxidant enzymes were decreased, whereas erythrocytic lipid peroxidation (LPO) and plasma nitrate (NO) level were significantly (p < 0.05) augmented in A. marginale-infected animals over healthy group. Parasitemia was positively correlated (p < 0.01) with erythrocytic LPO and plasma NO and negatively correlated (p < 0.01) with hematological indicators and antioxidant enzymes. In addition, erythrocytic LPO was negatively correlated (p < 0.01) with the hemoglobin, erythrocyte count, and packed cell volume. From the present study, it can be concluded that anaplasmosis in crossbred calves is associated with a parasitic load-dependent oxidative damage as indicated by poor antioxidant status and enhanced oxidative stress, which are contributed to severe anemia.     

Swietenine: A potential oral hypoglycemic from Swietenia macrophylla seed

Swietenine, a tetranortriterpenoid, was isolated from the Swietenia macrophylla seeds. The in vivo hypoglycemic activity was evaluated against neonatal-streptozotocin induced type 2 diabetic rats. Oral administration of swietenine at 25 and 50 mg/kg body weight per day to diabetic rats was found to possess significant dose dependant hypoglycemic and hypolipidemic activity in type 2 diabetic rats.     

Depressed polymorphonuclear cell functions in periparturient cows that develop postpartum reproductive diseases

The study was planned to see if there is any important and significant changes in the PMN function in cows suffering from postpartum reproductive diseases (PRD). Blood sampling was done from 41 pregnant cows on 15 days prepartum (?15d), calving day (0d), 15 days (15d) and 30 days (30d) postpartum and thorough gynaecological examination was performed on 0d, 15d, 30d and 45d for diagnosis of PRD like retained placenta (RP), clinical metritis (CM), clinical endometritis (CE) and delayed involution of uterus (DIU). The heparinised blood was used for isolation of PMN leukocytes for estimation of superoxide (SO), hydrogen peroxide (H₂O₂) and enzyme myeloperoxidase (MPO) activity in each group of cows. The SO production (ΔOD) was greater for normal (0.19 ± 0.05) than cows suffering from RP (?0.12 ± 0.09), CM (?0.15 ± 0.13) and CE (?0.07 ± 0.05) at -15d. The mean value was greater for normal cows (0.12) than the cows with PRD (0.05 to 0.9) at 30d. The H₂O₂ production was greater for normal than cows with PRD at all sampling days and significantly greater than cows with RP and CE at 15d (p < 0.01) and 30d (P < 0.05). The MPO activity (μmol/1 × 10⁷) was greater for normal (18.77 ± 1.27) than for RP (12.52 ± 2.57) and CM (11.31 ± 3.30) cows on 0d. The depressed capability of the PMN from the cows with PRD to produce SO, H₂O₂ and MPO during the periparturient period indicated their association with the development of RP, CM and CE.     

Ovsynch Plus protocol improves ovarian response in anovular Murrah buffaloes in low‐breeding season

The objective of the study was to evaluate the efficacy of ovarian response and pregnancy rate in anovular buffaloes following Ovsynch and Ovsynch Plus protocols. Buffaloes (n = 55) were divided into two groups: Ovsynch group (n = 26): GnRH (10 μg, GnRH1) on Day 0, PGF₂α (25 mg) on Day 7, GnRH (10 μg, GnRH2) on Day 9; Ovsynch Plus group (n = 29): 500 IU equine chorionic gonadotropin (eCG) 72 hr (day ?3) prior to Ovsynch protocol, followed by fixed timed artificial insemination (FTAI) 6 and 24 hr after GnRH2 injection in bot groups. Transrectal ultrasonography was performed daily, that is, from day 0 and ?3 in Ovsynch and Ovsynch Plus group, respectively for ovarian response and pregnancy diagnosis at day 30 post‐insemination. In Ovsynch Plus group, administration of eCG prior to GnRH1 increased (p < .001) the diameter (mm) of dominant follicle (DF) from 10.15 ± 0.26 to 12.23 ± 0.34 within 72 hr of treatment resulting higher ovulatory response to GnRH1. Ovulation after GnRH1 was higher (p < .01) in Ovsynch Plus group (96.6%) than Ovsynch group (61.5%). However, ovulation rate to GnRH2 was similar (p > .05) between groups (Ovsynch group: 76.9% vs. Ovsynch Plus group: 70.0%). Mean DF diameter (mm) that ovulated to both GnRHs was higher (p < .01) than non‐ovulated counterparts in both groups (Ovsynch group: 10.80 ± 0.27 vs. 8.47 ± 0.53; Ovsynch Plus group: 11.99 ± 0.24 vs. 9.5 ± 0.63). Pregnancy was established in buffaloes which responded to both GnRHs, irrespective of groups, being higher (p = .52) in Ovsynch Plus group (34.5%) than Ovsynch group (23.1%), though non‐significant. In summary, this study showed that eCG inclusion prior to Ovsynch regimen improves ovulatory response in anovular buffaloes during low‐breeding season.     

<Emphasis Type="Italic">Fusarium</Emphasis> elicitor-dependent calcium influx and associated ros generation in tomato is independent of cell death

Fusarium oxysporum f. sp. lycopersici elicitor (EFOL-2) treatment induces cytosolic influx of calcium in Fusarium-resistant tomato suspension culture. The calcium signature was found to be biphasic, which is characteristic of recognition of oligosaccharides in the elicitor preparation. Further, several lines of evidence such as, (i) attainment of saturation level of the [Ca²⁺]_cyt at a definite extra-cellular calcium concentration (ii) prominent reduction in EFOL-2-induced influx in [Ca²⁺]_cyt on treatment with the calcium channel blockers verapamil and diltiazem and (iii) establishment of a refractory stage of [Ca²⁺]_cyt level upon repeated stimulation by EFOL-2, is indicative of receptor-mediated activation of the calcium channel for cytosolic elevation. In addition, inhibition of EFOL-2-induced [Ca²⁺]_cyt increase by protein kinase inhibitor staurosporine and wortmannin indicate phosphorylation is a regulatory event of calcium influx. Additionally, monitoring of cell death on EFOL-2 treatment indicated that the degree of ROS generation is not capable of inducing cell death. Inhibition of ROS generation on two separate occasions such as, calcium-free media and on treatment with inhibitors causing calcium channel occlusion revealed ROS generation as a successive event of calcium influx.     

Relationships among bovine male and female reproductive traits

No significant relationship (p greater than 0.05) was found between age at puberty in heifers and the age and scrotal circumference at puberty in related bulls. There was a significant effect (p less than 0.01) of genotype and sire on age at puberty of heifers and a significant effect (p less than 0.05) of genotype on weight at puberty in heifers. There was a significant effect of genotype on age (p less than 0.01) and weight (p less than 0.05) at puberty of bulls. A significant difference (p less than 0.05) in age at puberty of bulls was found between the 2 methods of assessing puberty. It is possible that the assessment of puberty of heifers at 2-month intervals may not have been precise enough to detect such a relationship and/or that the variation in genotypes and ages in this study were too great to establish such a relationship.     

An evaluation of calf castration by intra-testicular injection of a lactic acid solution

This experiment evaluated intra-testicular injection of a sclerosing drug, lactic acid, for castration of bulls. Its use was compared in 58 Brahman cross calves (50 to 128kg) with the general practice of open surgical castration. Chemical castration appeared to be more painful than surgical castration, though post-operative swelling and pain appeared similar for both methods. Chemical castration took 3 times longer than surgical castration (58 sec v 20 sec; P less than 0.01). Scrotal necrosis occurred in 25% of chemically-castrated calves and appeared due to drug leakage from the testes under the high pressure of injection. Healing time for chemical castrates was approximately twice that for surgical castrates. Five chemically-castrated calves (18%) retained one testis. Though all 5 were rendered sterile, each maintained androgenesis. This led to secondary male behaviour which caused management problems. Castration method did not influence post-operative growth. It is concluded that lactic acid administration is not a suitable alternative to the open surgical technique for castration of Brahman cross calves.