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321.
Abha Agnihotri K. R. Shivanna S. N. Raina Malathi Lakshmikumaran Shyam Prakash V. Jagannathan 《Plant Breeding》1990,105(4):292-299
Intergeneric hybridization is one of the effective methods to broaden the genetic base of cultivated species. Raphanus sativus, a member of the subtribe Raphaninae, has very hard pods at threshing time. In an attempt to transfer shattering resistance to Brassica napus, Raphanobrassica was used as the male parent in crosses with Brassica napus. Plantlets were obtained by embryo rescue and were further multiplied in vitro by micropropagation of nodal segments. Morphology, cytology and DNA analysis confirmed the hybrid nature of these plants. They were backcrosscd with Brassica napus and the progeny was raised. Plants of BC1 and BC2 generations showed wide variation in morphology, chromosome number and pollen fertility. Some of the plants showed up to 95 % pollen fertility and resistance to shattering, indicating the potential for developing B. napus with resistance to shattering. 相似文献
322.
S. Prakash I. Ahuja H. C. Upreti V. Dinesh Kumar S. R. Bhat P. B. Kirti V. L. Chopra 《Plant Breeding》2001,120(6):479-482
An alloplasmic mustard, Brassica juncea, has been synthesized by placing its nucleus into the cytoplasm of the related wild species Erucastrum canariense to express cytoplasmic male sterility. To achieve this, the sexual hybrid E. canariense (2n=18, EcEc) ×Brassica campestris (2n= 20, AA) was repeatedly backcrossed to B. juncea (2n= 36, AABB). Cytoplasmic male‐sterile (CMS) plants were recovered in the BC4 generation. These plants are a normal green and the flowers have slender, non‐dehiscing anthers that contain sterile pollen. Nectaries are well developed and female fertility is > 90%. The fertility restoration gene was introgressed to CMS B. juncea from the cytoplasmic donor E. canariense through pairing between chromosomes belonging to B. juncea with those of the E. canariense genome. The restorer plants have normal flowers, with well‐developed anthers containing fertile pollen. Meiosis proceeds normally. Pollen and seed fertility averaged 90% and 82%, respectively. F1 hybrids between CMS and the restorer are fully pollen fertile and show normal seed set. Preliminary results indicate that restoration is achieved by a single dominant gene. The constitution of the organelle genomes of the CMS, restorer and fertility restored plants is identical, as revealed by Southern analysis using mitochondrial and chloroplast probes atp A and psb D, respectively. 相似文献
323.
324.
B. Prakash S. K. Saha K. Khate N. Agarwal S. Katole N. Haque C. Rajkhowa 《Journal of animal physiology and animal nutrition》2013,97(2):297-304
The aim of the study was to investigate the effect of feeding different diets on fermentation, enzyme activities and microbial population in the rumen fluid of mithun (Bos frontalis). In a randomized block design, 20 male mithun (6–8 months of age, 152 ± 12.6 kg body weight) were randomly divided into four experimental groups (n = 5/group) and fed experimental diets ad libitum for 180 days. The diet R1 contained tree foliages (TF), R2 comprised of 50% concentrate mixture (CM) and 50% TF, R3 contained 50% CM and 50% rice straw, and R4 contained 50% CM, 25% TF and 25% rice straw. Rumen liquor was collected at 0 and 180 days of the experiment for estimation of different ruminal parameters and a digestion trial was conducted at the end of the experiment. Rumen fluid was analysed for pH, ammonia nitrogen (NH3‐N), total‐N, ruminal enzymes, short chain fatty acid (SCFA) and microbial profile. The relative quantification of ruminal microbes was carried out with real‐time PCR using bacteria as the house keeping gene. The dry matter intake, nutrients digestibility, body weight gain, NH3‐N, total‐N, carboxymethyl cellulase, avicelase, xylanase, amylase, protease and molar proportion of butyrate were (p < 0.05) higher in mithun fed R2, R3 and R4 compared to those fed R1 diet. In contrast, increased (p < 0.05) ruminal pH, molar proportion of acetate and, acetate to propionate ratio was recorded in mithun fed only TF than those fed concentrate supplemented diets. Similarly, an increase (p < 0.05) in the population of Fibrobacter succinogenes, Ruminococcus flavefaciens and total bacteria were evident in mithun fed R2, R3 and R4 compared to those fed R1. Therefore, it is concluded that TF 25% and/or rice straw 25% along with CM 50% may be fed to the growing mithun for improved rumen ecology, nutrient utilization and thus better performance under stall fed system. 相似文献
325.
Bhosale P Ermakov IV Ermakova MR Gellermann W Bernstein PS 《Journal of agricultural and food chemistry》2004,52(11):3281-3285
A rapid nondestructive estimation of carotenoid levels in intact fruits and vegetables and their juices could have great value when selecting nutritionally valuable crops for further propagation and commercial use. Carotenoid levels of a variety of agricultural products and juices were measured using resonance Raman spectroscopy and compared to levels determined by extraction and high-pressure liquid chromatography. A strong correlation was observed between the two methods when evaluating juices and when comparing different strains of intact tomatoes at the same stage of ripening. 相似文献
326.
The objectives of this study were to establish the characteristics of oestrous behaviour in Ovsynch (induction of ovulation through administration of GnRH-PGF2-GnRH in a systemic manner on 0, seventh and ninth day respectively) and Ovsynch plus Norprolac (Quinagolide hydrochloride – an inhibitor of prolactin secretion) treated Murrah buffalo heifers and to determine the relationships between this behaviour and the plasma concentrations of oestradiol-17β (E2), total oestrogen, and progesterone. Oestrus was detected by visual observations of oestrus signs, per rectal examination of genitalia and bull parading thrice a day during treatment period. Among all the symptoms, it was observed that bull mounting of heifers in oestrus was highest. Examination of genital tracts per rectum revealed that the cervix was relaxed, uterus was turgid and ovaries had palpable follicle in animals with oestrus. The peak concentrations of E2 (10.81 ± 0.62 pg/ml) and total oestrogen (17.11 ± 1.21 pg/ml) occurred at 9.45 ± 0.85 and 9.64 ± 0.93 h after second GnRH administration, respectively, in Ovsynch treated animals. However, the peak levels of E2 (20.02 ± 2.87 pg/ml) and total oestrogen (32.71 ± 3.15 pg/ml) occurred at 10.18 ± 0.50 and 10.36 ± 0.75 h after second GnRH administration, respectively, in Ovsynch plus Norprolac treated animals. Plasma progesterone concentration was basal (0.20 ± 0.001 ng/ml) during the peri-oestrus period. The plasma progesterone concentration was the lowest on the day of oestrus and increased to register a peak on day 13 ± 2 of the cycle. Oestrous behaviour was positively correlated with the peak concentration of E2 (p < 0.001) and total oestrogen (p < 0.001) during the peri-oestrus period. Inhibition of prolactin by Norprolac administration significantly increased the concentration of E2 and total oestrogen during oestrus in buffaloes in comparison to those recorded in animals subjected to Ovsynch protocol alone. In conclusion, our results suggest that the peak concentrations of E2 and total oestrogen and mean level of E2 and total oestrogen during the peri-oestrus period are the important factors contributing the behavioural manifestation of oestrus in buffalo cows. 相似文献
327.
Virendra Singh MVSc Amarpal MVSc PhD Prakash Kinjavdekar MVSc PhD & Hari P Aithal MVSc PhD 《Veterinary anaesthesia and analgesia》2009,36(1):77-85
ObjectiveTo evaluate and compare the effect of epidural bupivacaine on analgesia produced by epidural xylazine or medetomidine in buffaloes.Study designProspective, blinded study.AnimalsTen male buffalo calves (6-8 months of age; body weight 70-90 kg) were used on two occasions to conduct a total of 20 investigations.MethodsCaudal extradural analgesia was produced in four buffalo calves each by the injection of either xylazine (0.05 mg kg?1), medetomidine (15 μg kg?1) or 0.5% bupivacaine (0.125 mg kg?1), or combinations of xylazine and bupivacaine (0.05 and 0.125 mg kg?1), or medetomidine and bupivacaine (15 μg kg?1 and 0.125 mg kg?1) at the first intercoccygeal extradural space. Analgesia was tested using deep pinprick stimuli.ResultsExtradural administration of xylazine or medetomidine resulted in complete analgesia of the tail, perineum, inguinal region and the upper parts of the hind limbs, which was faster in onset and longer in duration in the medetomidine group than in the xylazine group. Addition of bupivacaine increased the intensity of the analgesia produced by xylazine, but not that produced by medetomidine. All the drugs caused mild to moderate ataxia, but signs of sedation were apparent only in animals which received xylazine or medetomidine. The extradural injections of all the drugs caused significant decrease in heart rate (p = 0.024), respiratory rate (p = 0.026) and rectal temperature (p = 0.036) from the respective baseline values, but the differences between the groups were not significant.ConclusionsMedetomidine produced a longer duration of analgesia than that produced by xylazine. Bupivacaine prolonged the analgesia produced by xylazine, but the analgesia produced by the combination of medetomidine and bupivacaine was not superior to that produced by medetomidine alone.Clinical relevanceBupivacaine may be used to prolong the extradural analgesia produced by xylazine, but not that produced by medetomidine in buffaloes. 相似文献
328.
Clantin B Delattre AS Rucktooa P Saint N Méli AC Locht C Jacob-Dubuisson F Villeret V 《Science (New York, N.Y.)》2007,317(5840):957-961
In Gram-negative bacteria and eukaryotic organelles, beta-barrel proteins of the outer membrane protein 85-two-partner secretion B (Omp85-TpsB) superfamily are essential components of protein transport machineries. The TpsB transporter FhaC mediates the secretion of Bordetella pertussis filamentous hemagglutinin (FHA). We report the 3.15 A crystal structure of FhaC. The transporter comprises a 16-stranded beta barrel that is occluded by an N-terminal alpha helix and an extracellular loop and a periplasmic module composed of two aligned polypeptide-transport-associated (POTRA) domains. Functional data reveal that FHA binds to the POTRA 1 domain via its N-terminal domain and likely translocates the adhesin-repeated motifs in an extended hairpin conformation, with folding occurring at the cell surface. General features of the mechanism obtained here are likely to apply throughout the superfamily. 相似文献
329.
Superacids, although first referred to as early as 1927, were only extensively studied in the last decade. Acidities up to 10(12) times that of sulfuric acid have now been obtained. The extremely low nucleophilicity of the counterions in superacidic systems is especially useful for the preparation of stable, electron-deficient cations, particularly carbocations. Many of these cations, which were formerly detectable only in the gas phase, can now be studied in solution. Novel organic syntheses that are not possible in ordinary acidic media can also be achieved in superacids, including syntheses of economically important hydrocarbons. The unique ability of superacids to bring about hydrocarbon transformations, even to activate methane to undergo electrophilic oligocondensation, can open up new fields in chemistry. 相似文献
330.
Prakash Nagabovanalli Basavarajappa Dhumgond Prabhudev Shruthi Goiba Pema Khandu Ashrit Shrenivas 《Paddy and Water Environment》2021,19(4):595-607
Paddy and Water Environment - Slag-based gypsum (SBG) is a synthesized product of steel industry. SBG has better plant nutritional value in terms of sulphur (S), calcium (Ca), phosphorus (P), iron... 相似文献