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11.
A. K. Nayak D. K. Sharma V. K. Mishra P. S. Minhas C. L. Verma 《Soil Use and Management》2008,24(4):337-343
Saline sodic soil with a high content of soluble carbonates is one of the important agricultural soils on the Central Indo‐Gangetic plains and elsewhere. Conventional reclamation procedures using gypsum application followed by vertical leaching (GC) is uneconomic; high ECe and precipitation of applied gypsum, reacting with soluble carbonates, reduce the efficacy of gypsum in these soils. This paper reports results from a project designed to evaluate reclamation by irrigation of the ploughed soil and turning of soil with a power tiller followed by flushing of standing water after 24 h, a second flushing after 7 days and subsequent application of gypsum and vertical leaching (GF2). Average rice and wheat production after GF2 significantly increased (25 and 62%, respectively) over the conventional practice. Compared with conventional treatment, GF2 significantly reduced the ECe and SAR of the soil and improved physical properties such as ζ‐potential, dispersible clay content, water stable aggregates expressed as MWD, and saturated hydraulic conductivity. Split application of gypsum between flushing (GF1/2 and GF2/3) gave similar results to GF2 in terms of soil amelioration and crop production. 相似文献
12.
Three VA-mycorrhizal fungi; Glomus occultum, Glomus aggregatum (local isolates) and G. mosseae (strain from Bangalore, India) were inoculated to assess their effect on growth of Acacia mangium in lateritic soil. All inoculations enhanced growth with respect to shoot height, root diameter, leaf area, chlorophyll content
and biomass of A. mangium significantly compared to uninoculated control seedlings. G. occultum proved most efficient among the three. The mycorrhizal dependency factor indicated that the growth of A. mangium was 57% dependent on G. occultum, 47% on G. mosseae and 46% on Glomus aggregatum. 相似文献
13.
14.
P. Routray A.K. Choudhary D.K. Verma P. Swain S.D. Gupta 《Aquaculture (Amsterdam, Netherlands)》2006,261(4):1204-1211
Cryopreservation of semen collected from dead fishes showed that it is possible to use it for fish production. We humanely killed individuals of the Indian major carp rohu, Labeo rohita and stored at different temperature regimes of 31 °C, 0 °C, − 10 °C and − 30 °C till 8 h. At every one hour interval semen from these fishes were collected by Pasteur pipette and evaluated for sperm yield/kg body weight, motility, pH, spermatocrit (%) and sperm count. The semen having suitable characteristics such as; 70% spermatocrit or above and motility index of 4 or above was cryopreserved by following a specific protocol. The cryopreserved semen of the dead fishes was stored for 7 days and then thawed in a water bath at 37 °C for 50 s. It was found that up to 8 h, spermatozoa of rohu were viable when stored at 0 °C or − 10 °C. Sperm collected after 8 h of fish death and maintained at 0 °C was the best stored condition that showed 30% larval survival. The spermatozoa collected 8 h after fish death was mostly normal as observed under scanning electron microscope and the total length of rohu spermatozoa was 25-30 μm. The hatchlings produced with this cryopreserved semen grew normally and juvenile fishes of rohu could be produced. This study suggests that germ cells such as spermatozoa of dead fishes can be cryopreserved and utilized for restoration of a species. It has the potential use in cryo-conservation of endangered fishes, restoration of animals through fertilization and genetic manipulation studies. 相似文献
15.
Kumar Chavlesh Singh Sanjay Kumar Verma Mahendra Kumar Pramanick Kallol Kumar Srivastav Manish Kaur Sukhdeep Kumar Rajeev Ranjan 《Genetic Resources and Crop Evolution》2022,69(2):645-659
Genetic Resources and Crop Evolution - The wild Malus germplasm is considered as a gene reservoir for various biotic and abiotic stresses tolerance/resistance genes, including important novel... 相似文献
16.
Bhutia Nangsol D. Sureja Amish K. Munshi A. D. Verma Manjusha Arya Lalit Krishnan S. Gopala Gurung B. 《Genetic Resources and Crop Evolution》2022,69(7):2485-2500
Genetic Resources and Crop Evolution - Luffa hermaphrodita Singh & Bhandari, known as Satputia, a semi-wild taxon originating from L. graveolens is an underutilized vegetable. It has a... 相似文献
17.
Summary A macro-mutant, E 100Y(M) in chickpea (Cicer arietinum L.) was found to affect several plant and seed characters. For plant type monogenic inheritance was observed. A single pair of recessive genes pt/pt was ascribed to this mutant. The mutant locus seemed to be exerting pleiotropic action. The utilization of this mutant for chickpea improvement has been discussed. 相似文献
18.
Summary Studies on the inheritance pattern of bacterial leaf spot (BLS), yellow mosaic (YM) and Cercospora leaf spot (CLS) reactions in crosses of BLS and YM resistant/tolerant but CLS susceptible × CLS resistant but BLS and YM susceptible parents indicated that resistances to BLS and CLS were governed by single dominant genes, whereas YM tolerance was a monogenic recessive character. The studies also indicated that these three genes were inherited independently. The simple inheritance pattern and independent assortment of the genes governing resistance/tolerance to these diseases suggest that the usual breeding methods will be adequate to develop multi-disease resistant mungbean cultivars.Paper XII in the series Studies on resistance in crops to bacterial diseases in India. 相似文献
19.
Y. S. Sodhi A. K. Pradhan J. K. Verma N. Arumugam A. Mukhopadhyay D. Pental 《Plant Breeding》1994,112(3):223-227
Eighteen genotypes of Brassica napus were crossed to a cytoplasmic male sterile (CMS) line of B. napus BO 15 carrying B. tournefortii cytoplasm (‘tour’ cytoplasm). Fourteen genotypes were found to be stable maintainers of the ‘tour’ CMS. Of the remaining four genotypes, GSL-1 and ‘Asahi-natane’ were found to be heterozygous and ‘Mangun’ and ‘Yudal’ were homozygous for the restorer gene. Analysis of the F1 and F2 progenies of (CMS) BO 15 בMangun’ and (CMS) BO 15 בYudal’ showed that fertility restoration is controlled by a single dominant gene. The availability of a number of stable maintainer lines and the simple inheritance pattern of fertility restorer gene makes ‘tour’ CMS a useful system for hybrid seed production in rapeseed. 相似文献
20.
Susheel Verma Jawahar L. Karihaloo Shailesh K. Tiwari Rani Magotra Awtar K. Koul 《Genetic Resources and Crop Evolution》2007,54(2):221-229
Eremostachys superba Royle ex Benth. (Lamiaceae) has undergone a severe decline in population size since its discovery in the North-western Himalayas
in late 19th century. One hundred and seventy-two plants from six populations in the Indian states of Uttar Pradesh and Jammu
& Kashmir, located between 0.45 km and 455.72 km apart from each other were evaluated for RAPD polymorphism. Sixteen random
primers generated 92 bands overall, 77 of which were polymorphic. Shannon’s index of genetic diversity within populations
(H
o) ranged between 0.305 and 0.421; the average within-population diversity (H
pop) was 0.389; and the total species diversity (H
sp) was 0.478. The population from Mohand (representing the type locality) had the fewest plants, at 18, and was genetically
the most depauperate. Among the other populations, ranging in size between 52 and 1,022 individuals, no relation between population
size and genetic diversity was evident. It is suggested that these six populations represent relics of a larger, extended
population, in which the presence of perennating rootstocks has helped preserve historic patterns of genetic diversity. AMOVA
revealed that 83.01% of the variation exists within populations, which was consistent with earlier studies on the reproductive
biology of E. superba, which indicated this species is predominantly allogamous. FST distances between all populations were significant, indicating
geographic differentiation despite some of them being closely separated. Habitat restoration and protection from indiscriminate
harvesting are proposed as primary strategies for conserving E. superba. Rejuvenation of the Mohand population through intrapopulation crossing between plants bearing diverse molecular phenotypes
is also suggested. 相似文献