Activation tagging of the floral inducer FT   总被引：5，自引：0，他引：5  

Kardailsky I  Shukla VK  Ahn JH  Dagenais N  Christensen SK  Nguyen JT  Chory J  Harrison MJ  Weigel D 《Science (New York, N.Y.)》1999,286(5446):1962-1965

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Underutilized and unexploited fruits of Indo-Burma hot spot,Meghalaya, north-east India: ethno-medicinal evaluation,socio-economic importance and conservation strategies     

T. K. Hazarika  Siljea Marak  D. Mandal  K. Upadhyaya  B. P. Nautiyal  A. C. Shukla 《Genetic Resources and Crop Evolution》2016,63(2):289-304

An attempt has been made during 2012–2014 at to enumerate the ethno-medicinal evaluation and socio-economic importance of underutilized and unexploited fruits among the Garo tribe of west Garo hills district, Meghalaya, north-east India. The study was based on extensive field surveys, sample collection and interviews with the traditional healers as well as old aged men and women and survey in rural markets regarding their market demand, price and season of availability. Altogether 66 underutilized and unexploited fruits belonging to 34 families have been enumerated in this paper. The documented fruits were mostly used by the rural people to cure a number of ailments. In addition, these fruits also have socio-economic importance in the rural life of the tribal people like use as constructional timbers, firewood, charcoal, fodder, making dye, yielding oil and a number of value added products. Although, these fruits play an important role in the social and cultural life of Garo people, but these valuable species have been vanishing at very faster rate due to lack of proper documentation. Therefore, the claimed therapeutic values of these species are to be critically studied to establish their safety and effectiveness and both in situ and ex situ conservation measures should be immediately undertaken to safeguard the valuable indigenous rural resources of the world.  相似文献   

Alkaloid Spectrum of Different Germplasm Lines in Opium Poppy (Papaver somniferum L.)     

Sudhir Shukla  S. P. Singh  H. K. Yadav  A. Chatterjee 《Genetic Resources and Crop Evolution》2006,53(3):533-540

The opium latex of 1470 individual plant samples of 98 germplasm lines were screened for five major economic alkaloids. The alkaloids profile showed that morphine content ranged from 9.20–20.86% with an average of 15.00 ± 0.267. Codeine ranged from 1.69–6.48% with arithmetic mean of 3.35 ± 0.091, thebaine from 0.52–7.95% with an average of 2.27 ± 0.116. Narcotine ranged from 8.79–17.97% with an average 8.79 ± 0.266 and papaverine content ranged from 0.00–6.07% with an average 1.18 ± 0.167 in over all the germplasm lines. The content of different alkaloids categorized into class interval which exhibited that maximum number of plants and accessions for morphine content fall in group of 10–15% followed by 15–20%, for codeine content in group of 2–4% followed by 4–6%, for thebaine content in 1–2% followed by 2–4%, for narcotine in 5–10% followed by 10–15% and for papaverine content 0–2%. 24 germplasm lines had morphine content above 16.0%. Similarly, 37 germplasm lines for codeine and 13 for thebaine showed consistently high content, i.e., above 3%. 33 germplasm lines had narcotine content above 9% and 20 lines exhibited papaverine content above 2%. Line BR 316 was found unique having thebaine content 6.27–9.33%. The probable reasons of increase or decrease of different alkaloids based on their biosynthetic pathway has been discussed in detail.  相似文献   

Use of resistant ACCase mutants to screen for novel inhibitors against resistant and susceptible forms of ACCase from grass weeds     

Shukla A  Nycholat C  Subramanian MV  Anderson RJ  Devine MD 《Journal of agricultural and food chemistry》2004,52(16):5144-5150

The aryloxyphenoxypropionic acid (AOPP) and cyclohexanedione (CHD) herbicides inhibit the first committed enzyme in fatty acid biosynthesis, acetyl CoA carboxylase (ACCase). The frequent use of AOPP and CHD herbicides has resulted in the development of resistance to these herbicides in many grass weed species. New herbicides that inhibit both the susceptible and resistant forms of ACCase in grass weeds would have obvious commercial appeal. In the present study, an attempt was made to identify molecules that target both the herbicide-sensitive and -resistant forms of ACCase. Seven experimental compounds, either CHD-like or AOPP-CHD hybrids, were synthesized and assayed against previously characterized susceptible and resistant forms of ACCase. All seven compounds inhibited ACCase from sensitive biotypes of Setaria viridis and Eleusine indica (I50 values from 6.4 to >100 microM) but were not particularly potent compared to some commercialized herbicides (I50 values of 0.08-5.6 microM). In almost all cases, the I50 values for each compound assayed against the resistant ACCases were higher than those against the corresponding sensitive ACCase, indicating reduced binding to the resistant ACCases. One compound, a CHD analogue, was almost equally effective against the resistant and susceptible ACCases, although it was not a very potent ACCase inhibitor per se (I50 of 51 and 76 microM against susceptible ACCase from S. viridis and E. indica, respectively). The AOPP-CHD hybrid molecules also inhibited some of the resistant ACCases, with I50 values ranging from 6.4 to 50 microM. These compounds may be good leads for developing ACCase inhibitors that target a wider range of ACCase isoforms, including those found in AOPP- and CHD-resistant weed biotypes.  相似文献   

EPR studies on gamma-irradiated barley seeds: identification of trapped electrons.     

L I Shukla  V Natarajan  T P Devasagayam  M D Sastry  P C Kesavan 《Journal of agricultural and food chemistry》2001,49(11):5273-5278

Electron paramagnetic resonance (EPR) studies were conducted on barley seeds exposed to normal (H(2)O) and deuterated (D(2)O) moisture, irradiated with 750 Gy at 77 K. Reported here, for the first time, are the trapped electrons formed on gamma-irradiation of seeds at 77 K. Electrons are stabilized/solvated with an increase in the moisture content (H(2)O/D(2)O) of seeds. The recombination of the trapped electron with radical cation gave intense thermoluminescence emission at 110 K. With the increase in temperature and the destruction of singlet, unmasking of an underlying heterogeneous population of free radicals was observed. These free radicals emanate mainly from the endosperm (approximately 95% by wt of the seed), whereas irradiated embryos show a broad multiplet of comparatively low amplitude. Radiolysis of carbohydrate, proteins (approximately 95% of endosperm), and lipids could possibly be responsible for the heterogeneous population of free radicals. Peroxyl radicals were also observed on annealing.  相似文献   

Effects of solar treatment on germination of sclerotia (Sclerotium rolfsii Sacc.) and on other soil mycoflora     

R. K. Singh  R. P. Shukla  R. S. Dwivedi 《Biology and Fertility of Soils》1990,10(2):152-154

Summary Only 10% of sclerotia germinated in a tarpcovered plot after 45 days of treatment while 50% of sclerotia germinated in the control plot. However, complete inhibition of sclerotia germination was not achieved. The maximum temperature recorded was 53°C, after 45 days of treatment in a tarped plot at 1 cm depth. The incidence of Acrophialophora fusispora, Aspergillus spp., Spicaria sp., and Trichoderma viride increased in soil after 45 days of the solar treatment.  相似文献   

Cyanobacteria in alkaline soil and the effect of cyanobacteria inoculation with pyrite amendments on their reclamation   总被引：3，自引：0，他引：3  

Kapil D. Pandey  Prabhu N. Shukla  Deen D. Giri  Ajai K. Kashyap 《Biology and Fertility of Soils》2005,41(6):451-457

The succession of cyanobacteria was studied in a usar (alfisol, solonetz, alkaline) soil, located in a tropical region of upper Gangetic plain, following the first rainfall for a period of 10 months (i.e., July–April). A dozen cyanobacteria were identified to grow on the soil surface and their appearance was in the following order: Microcoleus sp., Calothrix brevissima, Scytonema sp., Cylindrosprmum licheniformae, Cylindrosprmum fertilissima, Nostoc calcicola, Nostoc punctiformae, Aphanothece parietina, Nostoc commune, Aulosira fertilissima, Phormidium sp., and Oscillatoria sp. Among these cyanobacteria, N. calcicola was the dominant species. N. calcicola was inoculated on the alkaline soil and incubated under ambient conditions in the light for 2 years in the laboratory. Changes in soil properties were more rapid after the incorporation of pyrite (FeS₂). Recovery was monitored by using a filamentous heterocystous cyanobacterium N. calcicola and its bicarbonate-resistant (HCO₃^–R) mutant. The mutant strain showed better response to modification of soil pH following growth in soil.  相似文献   

Tolerance of Drought and Temperature Stress in Relation to Increased Antioxidant Enzyme Activity in Wheat   总被引：3，自引：0，他引：3  

R. K. Sairam  P. S. Deshmukh  D. S. Shukla 《Journal of Agronomy and Crop Science》1997,178(3):171-178

An experiment was conducted with three wheat genotypes differing in their sensitivity to moisture and/or temperature stress to study the relationship of the chloroplast antioxidant system to stress tolerance. Both moisture stress and temperature stress increased glutathione reductase and peroxidase and decreased membrane stab-iltty, chlorophyll content and chlorophyll stability index in all genotypes. Under moisture stress. DL 153–2 showed the highest membrane stabihty index, chlorophyll content, chlorophyll stability index, glutathione reductase activity and peroxidase activity. However, under elevated temperature conditions, HD 2285, and to a lesser extent DL 153–2, showed higher membrane stability, chlorophyll content and chlorophyll stability index and activities of glutathione reductase and peroxi-dase. Raj 3077, which is sensitive to both drought and temperature stress, showed the lowest membrane stability, chlorophyll content and chlorophyll stability index and glutathione reductase and perosidase activity under elevated temperature as well as drought conditions. Thus, it can be concluded that tolerance of the genotype to moisture and/or temperature stress is closely associated with its antioxidant enzyme system.  相似文献   

Genetic divergence in parental genotypes and its relation with heterosis, F1 performance and general combining ability (GCA) in opium poppy (Papaver somniferum L.)     

H. K. Yadav  Sudhir Shukla  S. P. Singh 《Euphytica》2007,157(1-2):123-130

Summary Genetic divergence in 110 population (20 parents and 90 F₁ hybrids) of opium poppy was studied by multivariate analysis. All the entries were grouped in 14 clusters. Out of 20 parents, ten were accumulated in one cluster and rest 10 distributed over seven clusters. Estimates of cluster distance showed that maximum intra-cluster distance was in -cluster IX (25.62) followed by cluster I (22.41), V (22.23) and IV (21.06). The inter cluster distances varied from 16.62 (between cluster XII and XIV) to 195.10 (between cluster IV and IX). The cluster analysis indicated substantial diversity among the parental genotypes, which had the potential to release considerable variation in their crosses. The first four principal components (PCs) with eigen values >1 accounted for 68% of variation among the population. The first and second components could account for 29 and 20% of the total morphological and alkaloidal variations, respectively. The PC1 was closely related to yield and yield related traits. The characters contributing greatest positive weight on PC1 were opium yield, plant height, stem diameter, capsule weight/plant and seed yield/plant. The possibilities of relationship between genetic divergence, F₁ performance, heterosis and GCA of parents have been explored.  相似文献   

Evaluation of foliage yield and leaf quality traits in Chenopodium spp. in multiyear trials     

Atul Bhargava  Sudhir Shukla  Deepak Ohri 《Euphytica》2007,153(1-2):199-213

Stability of foliage yield and its quality components has not been investigated in vegetable chenopods due to their underutilized status. The objectives of the present study were to assess genotype-environment interactions (GEI), determine stability of yield and quality components and to compare different parametric and non-parametric stability parameters. The present study reports for the first time the effect of genotype and environment on foliage yield and three leaf quality traits viz. carotenoid, ascorbic acid and protein content in different species of Chenopodium. Twenty accessions comprising four species were tested in a randomized block design with three replications across four environments. For all the four traits the largest sum of squares was accounted for by the genotypes, followed by GEI and environments. Highest foliage yield of 16.02 q/ha was obtained from C. album PRC 9804, while the lowest was from C. album CHEN 63/80 (4.01 q/ha). Many indigenous accessions of C. album (PRC 9801, IC 107299, ‘Chandigarh’, ‘local’ and ‘NEFA’) were unstable both for foliage yield and most of the quality traits. Most of the exotic accessions of C. giganteum were both stable and high yielding, thus, reflecting the potential of these accessions for future breeding programs/variety release.  相似文献