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The aim of the present study was to examine whether cumulus and fibroblast cell nuclear-transferred oocytes, which have high and low potential to develop into normal calves, respectively, are different in terms of in their patterns of timing of first cleavage and in their relationships between timing of first cleavage and in vitro developmental potential. The timing of first cleavage was similar in both types of nuclear-transferred and in vitro fertilized oocytes. More than 86% of the oocytes cleaved within 24 h after activation or in vitro fertilization; these oocytes contributed to more than 98% of the total number of blastocysts in all three groups. The potential of oocytes that cleaved at different intervals to develop into blastocysts differed among the groups. The developmental potential of the cumulus cell nuclear-transferred oocytes and in vitro fertilized oocytes decreased with the increase in time required for cleavage. Fibroblast cell nuclear-transferred oocytes that cleaved at 20 h, an intermediate cleaving time, had higher potential to develop into blastocysts. The results of the present study suggest that the type of donor nucleus used for nuclear transfer affects the timing of first cleavage. 相似文献
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Ether and methanol extracts of Ixora coccinea dry leaves were tested for their antimicrobial activity. Ether fraction was found to be more active than the methanol fraction. 相似文献
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Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献
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Gograj Singh Jat Anilabh Das Munshi Tusar Kanti Behera Harshwardhan Choudhary Prasanta Dash Amarnath Ravindran 《The Journal of Horticultural Science and Biotechnology》2019,94(1):24-32
Gynoecious is an important economic trait of cucumber for determinant of earliness and yield, yet genetic mechanism is not well understood for this trait. The experiment was conducted using F2 mapping population by crossing of PPC-2, a gynoecious and parthenocarpic line with Pusa Uday (monoecious and non-parthenocarpic cultivar). Out of 179 SSR markers screened, 39 markers differentiated the gynoecious and monoecious parents. However, only 17 markers were segregating with F2 mapping population, those were used for genotyping and linkage map analysis and these markers were placed along with F locus on chromosome 6 covering a total distance of 100.4cM. The SSR markers, SSR13251 and UW020605 were found to be closely linked to gynoecious (F) locus at 1.0 and 4.5 cM, respectively. The segregation of F2 population of PPC-2 × Pusa Uday and GPC-1 × Punjab Naveen and test crosses for sex type herein suggested that single dominant gene controlled the gynoecious sex expression in cucumber particularly in gynoecious genotypes PPC-2 and GPC-1. Therefore, the monogenic dominant nature of gynoecious sex identified in the present experiment and SSR markers closely linked to the F locus will be useful in marker-assisted backcross breeding for transfering gynoecious trait into horticulturally desirable varieties. 相似文献
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Aditya Kumar Joshi Pallavi Pant Prasant Kumar Amarnath Giriraj Pawan Kumar Joshi 《Small-Scale Forestry》2011,10(1):83-96
For any country, the forest policy is an important guideline to maintain forest resources and their interaction with other
land uses. India devised its first National Forest Policy (NFP) back in 1894. There has been a paradigm shift from timber
production to forest conservation followed by community-based agroforestry and social forestry bringing a change in perspective
towards forest resources. This change has been socio-economic, cultural and ecological. Since the 1952 NFP, there has been
an advocacy for 33% forest cover with a 60% forest cover in mountainous and hilly regions. This objective was reiterated in
the NFP 1988 and also confirmed in the National Forestry Commission report in 2006. This paper reviews the probable reasons
for these targets. This paper also analyzes forest cover trends at state level and assesses the likelihood of meeting the
prescribed policy targets under present perspective of land use practices. Only three Indian states meet the prescribed policy,
while three more have the potential to do so, if their state wasteland area is afforested. Among the rest, a few states may
achieve the 33% goal provided land conversion to tree cover is not hindered, and adequate resources are available at state
level. The Planning Commission (XI Five-year Plan, 2007–12) has emphasized inclusion of other natural ecosystems (including
treeless areas and trees outside forests) to forest cover. The paper also examines the above prescribed targets in light of
the Planning Commission recommendations. It is argued that that the NFP should be re-visited and revised to meet the targets,
along with setting a more realistic and attainable target for Indian forest and tree cover. 相似文献
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A method is described for determining heats of heterolysis, DeltaH(het), from the heats of reaction of resonancestabilized carbenium ions with carbanions in solution. These results can be converted into heats of homolysis, DeltaH(homo), for the same bonds by combining DeltaH(het) values with electron transfer energies, deltaG(ET) (deltaG(ET) approximately deltaH(ET)), obtained from redox potentials of the reacting ions. The results provide a comprehensive tabulation of DeltaH(het), DeltaH(homo), and DeltaG(ET) values for an extended series of organic compounds and are examined in terms of their interrelationships and a number of related properties of the ions and radicals. 相似文献
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Tripathi Rachana Agrawal Nisha Kumawat Giriraj Gupta Sanjay Kuchlan Mrinal Maranna Shivakumar Nataraj Vennampally Kuchlan Punam Satpute Gyanesh K. Ratnaparkhe Milind B. Rajesh Vangala Chandra Subhash Bhatia Virender S. Chand Suresh 《Genetic Resources and Crop Evolution》2021,68(6):2455-2467
Soybean is a temperate photosensitive crop but has adapted to sub-tropical and tropical countries of lower latitudes also. Photoperiodic and maturity genes confer latitudinal adaptation in this crop. Genotyping of accessions of higher latitudes have shown the role of photoinsensitivity, conferred by recessive photoperiodic alleles (e1/e2/e3/e4), in adaptation of the crop to high latitudes but information is not available for lower latitudinal countries like India. We genotyped and calculated the photosensitivity of 101 cultivated Indian soybean varieties and found that majority of the varieties (86) were photosensitive and had the dominant alleles at these loci. Four genotypic classes (e1-as/E2/E3/E4, E1/e2/e3/E4, E1/e2/E3/E4 and E1/E2/e3/E4) were observed for varieties with recessive alleles. Photoinsensitive alleles at E1 and E2 loci significantly reduced the days to flower, maturity and photosensitivity percentage. Adaptive role of photoperiodic alleles was inferred from breeder seed requirement of these varieties for 35 years. Although the photosensitive class contributed 81% to the total seed requirement the weighted mean contribution of this class (380 Q/year) was far less than that of photoinsensitive class (648 Q/year). Photoinsensitivity is essential for perpetuation of crop in higher latitudes. Present report highlights the novel role of photoinsensitive alleles in adaptation of soybean to rainfed, short growing and sub-tropical conditions of lower latitudes by conferring earliness.
相似文献10.
Solena amplexicaulis (Lam.) Gandhi (Cucurbitaceae) is a promising vegetable in Southeast Asia. Infestation of Aulacophora foveicollis Lucas (Coleoptera: Chrysomelidae) adults on leaves of the crop plant causes death of the plant and reduces crop production. Currently, growers are applying insecticides to control this pest, which are harmful to health and environment. Hence, an attempt has been made to find out allelochemicals from leaves attracting the insect, which might be used for ecofriendly pest management program. The emission of volatiles was detected from undamaged leaves of herbivore-induced plants after 24 h and 120 h of continuous females feeding on lower leaves of the same plants by GC-MS and GC-FID analysis. The insect showed attraction to systemically released volatiles from herbivore-induced plants against unharmed plants in Y-shaped glass tube olfactometer bioassays. The insect was attracted to a synthetic blend of 1.2 µg linalool oxide + 3.2 µg nonanal + 1.5 µg trans-2-nonenal dissolved in 20 µL CH2Cl2 in olfactometer and wind tunnel bioassays, and hence, this blend could be used in development of baited traps in pest management strategies. 相似文献