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881.
Gupta Pratima Chaurasia Shyam Sunder Maiti Prasanta Kumar Kar Anand 《Water, air, and soil pollution》2000,117(1-4):245-250
The possible involvement of free radicals in the cadmium-induced thyroid dysfunction with special reference to hepatic type-I iodothyronine 5′-monodeiodinase (5′-D) enzyme activity has been studied in cockerels. Cadmium chloride (CdCl2) administration (i.m. 0.5, 1.0 and 2.0 mg/kg body weight for 30 days) enhanced hepatic lipid peroxidation (LPO) but, decreased 5′-D activity and serum triiodothyronine (T3) concentration. Serum thyroxine (T4) was decreased only by the highest dose indicating that cadmium (Cd) is thyroid inhibitory only at higher doses. Liver appears to be highly sensitive to the metal as disruption of membrane configuration evidenced by increased hepatic LPO and inhibition of 5′-D enzyme activity were observed by all the three doses. We suggest that, Cd-induced inhibition of extrathyroidal conversion of T4 to T3, the major source of the generation of latter hormone, is dose dependent and the free radicals generated due to Cd intoxication could be one of the mechanisms involved in the inhibition 5′-D activity in hepatic tissues. 相似文献
882.
Anther culture of recalcitrant indica × Basmati rice hybrids 总被引:1,自引:1,他引:0
U. Bishnoi R.K. Jain J.S. Rohilla V.K. Chowdhury K.R. Gupta J.B. Chowdhury 《Euphytica》2000,114(2):93-101
Fertile, green, di-haploid plants were obtained at high frequencies from several indica × Basmati rice F1 hybrids and/or F2 plant populations using an improved anther culture procedure. Anthers from cold-pretreated (10 °C for 10 d) panicles of six indica (HKR120, HKR86-3, HKR86-217, PR106, Gobind andCH2 double dwarf) and two Basmati rice (Basmati
370,Taraori Basmati) varieties and 14 heterotic indica ×Basmati F1/F2 hybrids were cultured in modified agarose-solidified N6M, Heh5M and RZM media. Best callus induction frequencies (2.6–78%)
were obtained in RZM medium containing 4% (w/v) maltose,2,4-D, NAA and kinetin. F2 plants compared to F1 hybrids and parental rice varieties, were more responsive to anther culture. Androgenesis frequencies of 31–78% were obtained
for indica × Basmati F2 plants in RZM medium in just 30 d which are comparable to or higher than that reported for japonica rice varieties and hybrids
involving japonica rice parent(s). Agarose (1.0% w/v)-solidified MS medium containing 3.0% maltose, kinetin, BAP, and NAA,
induced green shoot regeneration in 0–51% of the anther-derived callide pending upon the genotype. High plant regeneration
frequencies (67–337 green plants per 1000 anthers)were obtained from anther calli of several F1hybrids (Gobind × Basmati 370 and HKR120 ×Taraori Basmati) and F2 plants (Gobind × Basmati370, Gobind × Taraori Basmati, HKR86-3 × TaraoriBasmati). A sample of 498 plants obtained from the
above hybrids, were transferred to pots with>90% survival; 8–78% of these plants had >5%spikelet fertility and were diploid.
In addition,18% of the haploid plants could be diploidized by submerging in 0.1% colchicine solution for 16–18 h. The improved
anther culture procedure reported here, resulted in several fold increase in the recovery of green plants from recalcitrant
indica × Basmati rice hybrids compared to previous published procedures. The study may accelerate the introgression of desirable
genes from indica into Basmati rice using anther culture as a breeding tool.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
883.
J. K. Verma Y. S. Sodhi A. Mukhopadhyay N. Arumugam V. Gupta D. Pental A. K. Pradhan 《Plant Breeding》2000,119(1):90-92
‘Polima’ cytoplasmic male sterility (CMS) was transferred from ‘Polima’ Brassica napus ‘ISN 706’to five different cultivars of Brassica campestris (‘Pusa kalyani’, ‘Pant toria’, ‘Candle’, ‘Tobin’ and ‘ATC 94211′) by repeated backcrossing. It was observed that, while ‘Polima’ CMS manifested complete and stable male sterility in the nuclear backgrounds of ‘Pusa kalyani’, ‘Pant toria’, and ‘Tobin’, the cultivars ‘Candle’ and ‘ATC 94211’possessed the restorer gene for this CMS in the heterozygous condition. An analysis of F1 and F2 generations of ‘Polima’‘Pusa kalyani’בCandle’ and ‘Polima’‘Pusa kalyani’בATC 94211’ revealed that restoration is controlled by a single dominant gene. Identification of stable maintainers and restorers of ‘Polima’ CMS could facilitate the development of hybrid varieties in B. campestris. 相似文献
884.
Mahesh Pujar Sushil Kumar Rajan Sharma Punna Ramu Raman Babu Shashi K. Gupta 《Plant Breeding》2023,142(4):506-517
Blast disease causes serious economic yield losses in pearl millet. Identification and introgression of genomic regions associated with blast resistance can help to develop resistant cultivars to minimize yield losses incurred from blast outbreaks. In this study, 384 advanced pearl millet genotypes were screened against six blast pathotype-isolates (major pearl millet growing agro-ecologies of India), namely, Pg 45, Pg 118, Pg 138, Pg 186, Pg 204 and Pg 232. Analysis of variance showed significant (P < .001) variation among genotypes for blast reaction (susceptible to resistance). ICMR 08111 and ICMR 10888 genotypes showed resistance to all six blast pathotypes. A genome-wide association study performed with 264,241 single nucleotide polymorphic markers could successfully identify 15 SNPs (P = 1.26 × 10−7 to 9.22 × 10−12) underlying the genomic regions governing blast-resistance across five different chromosomes. The SNPs reported had a significant association in at least two of the three models tested (GLM, MLM and Farm CPU). These SNPs can be used in pearl millet-resistant breeding programmes after their function has been validated across different genetic backgrounds. 相似文献
885.
Antagonistic effect of Pseudomonas spp. on pathogenic fungi and enhancement of growth of green gram (Vigna radiata) 总被引:4,自引:0,他引:4
species were isolated from the rhizosphere of green gram [Vigna radiata (L.) Wilczek] and some of the rhizobacterial isolates were found to have a wide range of antifungal activity inhibiting growth
of the phytopathogenic fungi Aspergillus sp., Curvularia sp., Fusarium oxysporum and Rhizoctonia solani in culture. These isolates also showed slight inhibition of the growth of a Bradyrhizobium strain (Vigna) in a spot test which was mainly a result of nutrient competition as culture supernatants of the Pseudomonas isolates did not inhibit the growth of bradyrhizobia but inhibited the growth of fungi. The rhizobacterial isolates produced
siderophores in Fe-deficient succinate medium. However, the inhibition of fungal growth by different Pseudomonas isolates in Luria Bertani and King's medium B which were not limiting in Fe3+ ions suggested that, besides siderophores, other antifungal compounds (antibiotics) produced by these rhizobacteria were
involved in antagonism. On coinoculation of green gram with Pseudomonas strains MRS13 and MRS16 and Bradyrhizobium sp. (Vigna) strain S24, there was a significant increase in nodule weight, plant dry weight and total plant N as compared to inoculation
with Bradyrhizobium strain S24 alone, suggesting that the nodule-promoting effects of Pseudomonas sp. lead to an increase in symbiotic N fixation and plant growth.
Received: 27 October 1997 相似文献
886.
BS Gallardo VK Gupta FD Eagerton LI Jong VS Craig RR Shah NL Abbott 《Science (New York, N.Y.)》1999,283(5398):57-60
Electrochemical methods were combined with redox-active surfactants to actively control the motions and positions of aqueous and organic liquids on millimeter and smaller scales. Surfactant species generated at one electrode and consumed at another were used to manipulate the magnitude and direction of spatial gradients in surface tension and guide droplets of organic liquids through simple fluidic networks. Solid microparticles could be transported across unconfined surfaces. Electrochemical control of the position of surface-active species within aqueous films of liquid supported on homogeneous surfaces was used to direct these films into periodic arrays of droplets with deterministic shapes and sizes. 相似文献
887.
Mohammad Shahbaz Akhtar Asim Kumar Pal Narottam Prasad Sahu Ciji Alexander Sanjay Kumar Gupta Arup Kumar Choudhary Ashish Kumar Jha Mysore Govindrajan Rajan 《Aquaculture Research》2010,41(7):991-1002
A 60‐day experiment was carried out to delineate stress mitigating and immunomodulatory role of dietary pyridoxine (PN) in Labeo rohita fingerlings exposed to endosulfan. Two hundred and seventy fingerlings were randomly distributed into six treatments in triplicates. Five iso‐caloric and iso‐nitrogenous purified diets were prepared with graded levels of pyridoxine. Six treatment groups were T0 (10 mg PN+without endosulfan), T1 (0 mg PN+endosulfan), T2 (10 mg PN+endosulfan), T3 (50 mg PN+endosulfan), T4 (100 mg PN+endosulfan) and T5 (200 mg PN+endosulfan). The role of pyridoxine on stress mitigation and immunomodulation was assessed by biochemical and haemato‐immunological parameters like aspartate aminotransaminase, alanine aminotransaminase, lactate dehydrogenase, malate dehydrogenase, superoxide dismutase and catalase were significantly (P<0.05) lower while acetylcholinesterase was significantly (P<0.05) higher in pyridoxine‐fed groups. Erythrocytes count, haemoglobin content and total serum protein, albumin, globulin, nitroblue tetrazolium and lysozyme activity were significantly (P<0.05) higher while cortisol and blood glucose were decreased significantly (P<0.05) in pyridoxine‐fed groups. Percentage survival after challenge with Aeromonas hydrophila was highest in T0 group. The results obtained in present study indicate that dietary pyridoxine supplementation at 100 mg PN kg?1 diet reduces the endosulfan‐induced stress and triggers immune response in L. rohita fingerlings. 相似文献
888.
Femi John Fawole N. P. Sahu K. K. Jain S. Gupta K. V. Rajendran N. Shamna Nalini Poojary 《Fish physiology and biochemistry》2017,43(3):677-690
A 60-day feeding trial was conducted to evaluate the haemato-biochemical, innate immune response, antioxidant capacity and histopathological changes in Labeo rohita fingerlings fed rubber protein isolates (RPI). One hundred and eighty fingerlings (average weight 4.45 ± 0.01 g) were distributed into five experimental groups in triplicate and fed with isonitrogenous and isocaloric diets. Soybean protein isolate (SPI) served as the reference diet (Control), and the treatment diets were formulated as RPI25, RPI50, RPI75 and RPI100 replacing 25, 50, 75 and 100% of SPI protein, respectively. The growth performance indices like final body weight (9.54–10.27 g), net weight gain (5.09–5.84 g), metabolic growth rate (4.54–5.02) and feed efficiency ratio (0.60–0.65) among the various groups were not significantly different (P > 0.05). All the haematological parameters, except red blood cells, showed no significant differences compared with the control group (P > 0.05). The immuno-biochemical parameters like albumin, globulin, total immunoglobulin, respiratory burst and lysozyme activities among the various groups did not differ significantly (P > 0.05). The stress enzyme such as superoxide dismutase (SOD), catalase (CAT) and oxidative stress marker malondialdehyde (MDA) showed no significant difference (P > 0.05). Histopathological examination of the liver revealed no marked changes. In summary, the results showed that RPI was well utilised by the fish and its inclusion did not generate any oxidative-induced stress, thus, RPI may be suggested as a potential replacement for SPI in fish diets without any detrimental effects. Hence, protein isolation offers a unique opportunity for the utilisation of rubber seed meal. 相似文献
889.