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101.
K. Ramesh K. Sammi Reddy I. Rashmi A.K. Biswas 《Communications in Soil Science and Plant Analysis》2016,47(3):369-374
Analysis of differential pore-volume distribution (DPVD) patterns of a commercial Clinoptilolite has been conducted experimentally using an analyzer by measuring the N2 adsorption isotherm. The commercial material was fractionated by sieving through sequential sieves: <125 µ (Z8; fine), 125–250 µ (Z9; medium), and >250 µ (Z10; coarse). The DPVD of the fractions were calculated from the hysteresis loop according to the adsorption and desorption curves of Dollimore-Heal (DH) model. The adsorption cycle had produced dissimilar differential pore volume distribution patterns. For the 10-nm pore width, fine and medium fractions had a maximum pore volume up to 0.0016 cm3/g nm, while the coarse fraction had a little greater value up to 0.002 cm3/g nm. Moreover, the medium fraction had too many hills and valleys in the DPVD. However, the desorption cycle–based DH analysis did not show any marked variation in the DPVD pattern. 相似文献
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104.
Kadiyala M. D. M. Mylavarapu R. S. Li Y. C. Reddy G. B. Reddy K. R. Reddy M. D. 《Paddy and Water Environment》2015,13(4):545-556
Paddy and Water Environment - The sustainability of traditional rice (Oryza sativa L.) cultivation in many Asian countries is being questioned due to severe water shortage conditions, envisaging... 相似文献
105.
Evidence for two predominant viral lineages,recombination and subpopulation structure in begomoviruses associated with yellow vein mosaic disease of okra in India 下载免费PDF全文
V. Venkataravanappa H. C. Prasanna C. N. Lakshminarayana Reddy M. Krishna Reddy 《Plant pathology》2015,64(3):508-518
Yellow vein mosaic disease (YVMD) caused by whitefly‐transmitted begomoviruses is an economically significant viral disease of okra. In this study, a survey of begomoviruses associated with YVMD was carried out in eight states and two union territories of India. A total of 92 full‐length DNA‐A components were sequenced and characterized. Sequence comparisons and population structure analysis revealed the existence of four begomovirus species. Two novel species were detected with several recombinationally derived genome fragments that probably originated from begomoviruses known to infect malvaceous and non‐malvaceous hosts. Among the four species, Bhendi yellow vein Maharastra virus (BYVMaV) and Bhendi yellow vein Madurai virus (BYVMV) were found to be predominant in okra, with BYVMV having a pan‐India distribution. There was evidence for a high degree of genetic variability and subpopulation structure within these four species. Neutrality tests suggested the occurrence of purifying selection acting upon these populations. The results of the current study have uncovered the diversity and genetic structure of okra‐infecting begomoviruses in India and generated potentially useful information for developing management strategies for YVMD. 相似文献
106.
Y. Yang D.J. Timlin D.H. Fleisher S.-H. Kim B. Quebedeaux V.R. Reddy 《Agricultural and Forest Meteorology》2009,149(6-7):1161-1167
An exponential decay function was fitted with literature data to describe the decrease in corn leaf expansion rate as predawn leaf water potential decreases. The fitted function was then applied to modify an existing leaf area simulation module in a soil–plant–atmosphere continuum corn simulation model (MaizSim) in order to simulate leaf area of corn plants at different water status. Data were collected from field for two years as well as from sunlit growth chambers located at USDA-ARS facilities in Beltsville, MD with different irrigation frequencies. Comparison among simulations and measurements indicated that the modified leaf area module improved leaf area simulation for corn plant under different drought stress. For plants under more severe drought stress, the improvement in leaf area simulation was more significant. These results suggested that the modified leaf area model presented an approach to mechanistically link corn leaf area with corn plant water status, and was suitable for integration with existing corn models that simulate corn leaf area. 相似文献
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Faisal Rashid Sofi S. M. Zofair Vijay Kumar Reddy Surasani K. K. Sabha Nissar Rajkumar Ratankumar Singh 《Journal Of Aquatic Food Product Technology》2013,22(3):253-263
Fatty fish have been recognized as potential raw material for production of minced meat; however, they are prone to oxidation and further deterioration. In the present study, the effect of washing and antioxidant (tannic acid) treatment on the quality of minced meat of Trachurus trachurus (horse mackerel) during frozen storage was observed. Minced meat of Trachurus trachurus was divided into three lots (T0, T1, and T2). T1 was washed with cold water, T2 with cold water containing tannic acid (100 mg/kg), and T0 was not washed. All the lots were frozen at ?40°C and stored at ?20 ± 2°C for 125 days and were subjected to biochemical, microbiological, and sensory evaluation at regular intervals of 25 days. The antioxidant treatment with tannic acid at the dosage used was found effective in minimizing the rancidity problems of minced meat (T2), compared to T0 and T1. During the whole period of storage, samples from T2 showed good quality in terms of microbiological, biochemical, and sensory analysis compared to T1 and T0. 相似文献
109.
Socio-Economic and Scientific Impact Created by Whitefly-Transmitted,Plant-Virus Disease Resistant Tomato Varieties in Southern India 下载免费PDF全文
John Colvin N Nagaraju Carlos Moreno-Leguizamon R M Govindappa T B Manjunatha Reddy SA Padmaja Neena Joshi Peter M Hanson Susan E Seal V Muniyappa 《农业科学学报》2012,11(2):337-345
Research carried out to assess the impact of open-pollinated Tomato leaf curl virus (ToLCV)-resistant tomatoes and hybrids on the livelihoods of resource-poor farmers in Southern India is described and discussed. Three high-yielding ToLCV-resistant tomato varieties were developed initially using conventional breeding and screening techniques involving inoculation by ToLCV-viruliferous whitefly, Bemisia tabaci. In 2003 and 2004, respectively, these varieties were released officially by the Karnataka State Seed Committee and the Indian Ministry of Agriculture through notification in the Gazette of India. From 2003 to 2005, eleven seed companies bought breeder seed of the ToLCV-resistant varieties and used them to begin breeding F1 hybrids from them. Socio-economic studies carried out to assess the benefits obtained from growing the ToLCV-resistant varieties found that farmers could gain up to 10 times the profit by growing the ToLCV-resistant varieties compared to the pre-existing ToLCV-susceptible varieties. Adoption of ToLCV-resistant tomatoes was also associated with reduced pesticide use. Extra income from tomato sales was prioritised by farmers to pay for children's education, better nutrition and medicines. In a joint effort with the commercial seed sector in India, a promotional field day was organised in 2007. As well as the three ToLCV-resistant varieties, 62 ToLCV-resistant hybrid tomatoes were exhibited during a farmer-field day by 17 commercial seed companies and several public institutes. Tomatoes with ToLCV-resistance are now grown widely in South India and seeds of the three open-pollinated varieties have been distributed to more than 12 countries. In 2007, a conservative estimate of the financial-benefit to cost of the research ratio was already more than 837:1. 相似文献
110.
W. S. Tsai Y. C. Huang D. Y. Zhang K. Reddy S. H. Hidayat W. Srithongchai S. K. Green F. -J. Jan 《Plant pathology》2008,57(3):408-416
Twenty-four isolates of Chilli veinal mottle virus (ChiVMV) from China, India, Indonesia, Taiwan and Thailand were analysed to determine their genetic relatedness. Pathogenicity of virus isolates was confirmed by induction of systemic mosaic and/or necrotic ringspot symptoms on Capsicum annuum after mechanical inoculation. The 3' terminal sequences of the viral genomic RNA were determined. The coat protein (CP) coding regions ranged from 858 to 864 nucleotides and the 3' untranslated regions (3'UTR) from 275 to 289 nucleotides in length. All isolates had the inverted repeat sequence GUGGNNNCCAC in the 3'UTR. The DAG motif, conserved in aphid-transmitted potyviruses, was observed in all isolates. All 24 isolates were considered as belonging to ChiVMV because of their high CP amino acid and nucleotide identity (more than 94·8 and 89·5%, respectively) with the reported ChiVMV isolates including the pepper vein banding virus (PVBV), the chilli vein-banding mottle virus (CVbMV) and the CVbMV Chiengmai isolate (CVbMV-CM1). Based on phylogenetic analysis, ChiVMV isolates including all 24 isolates tested, PVBV, CVbMV and CVbMV-CM1 can be classified into three groups. In addition, a conserved region of 204 amino acids with more than 90·2% identity was identified in the C terminal of the CP gene of ChiVMV and Pepper veinal mottle virus (PVMV), and may explain the serological cross reaction between these two viruses. The conserved region may also provide useful information for developing transgenic resistance to both ChiVMV and PVMV. 相似文献