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81.
This paper examines how agroforestry-based farming systems evolved in the Dhanusha district of Nepal following the conversion of forest into agriculture during the early 1950s. Some data are from two focus group discussions with agroforestry farmers and one meeting with agroforestry experts. The farmers?? discussion traced the development of farming practices from 1950 to 2010 to identify the drivers of land use change. The experts?? discussion resulted in a scale to differentiate the prevailing farming systems in the study area considering five key components of agroforestry: agricultural crops, livestock, forest tree crops, fruit tree crops and vegetable crops. Data related to the system components were collected from the randomly selected households. The study reveals that land use had generally changed from very simple agriculture to agroforestry, triggered by infrastructure development, technological innovations, institutional support (subsidies and buy-back guarantees) and extension programs. A range of farming systems with varying degrees of integration was evident in the study area: simple agriculture; less integrated agroforestry; semi-integrated agroforestry and highly integrated agroforestry. The three types of agroforestry systems, which are the focus of this study, varied significantly in terms of farm size, cropping intensity, use of farm inputs, tree species diversity, tree density, home to forest distance and agricultural labour force. 相似文献
82.
Abstract: The papers in this special issue are the product of a comparative interdisciplinary workshop on ‘Natural Resources and Violent Ethnic Conflicts in the Asia Pacific Region’ held in Honolulu, Hawaii, 18–20 March 2005. The workshop brought together scholars who study conflicts between ethnic groups and those who study conflicts over natural resource claims in order to examine the interplay of resources and ethnicity and to seek answers to the question of why violence occurs in some cases and not in others. Both sets of scholars agreed on some points but disagreed on others. They agreed that ethnic and resource grievances occur not so much out of objective deprivation but out of ‘relative deprivation’ when groups compare their situation with others, to the past, or to future expectations. They both stressed the role of democratic processes in alleviating resource competition and ethnic conflicts – but they did this in different ways. The perspectives and solutions offered by these papers sum to a deeper and more contextualised understanding of the cause of conflict and to mutually reinforcing solutions for resolving them. 相似文献
83.
Molecular mapping of genomic regions harboring QTLs for stalk rot resistance in sorghum 总被引:1,自引:0,他引:1
P. Srinivasa Reddy B. Fakrudin Rajkumar S. M. Punnuri S. S. Arun M. S. Kuruvinashetti I. K. Das N. Seetharama 《Euphytica》2008,159(1-2):191-198
Stalk rot, also called as charcoal rot in India, caused by Macrophomina phaseolina, is an economically important, soil borne disease in major sorghum growing areas across the world. A population of F9 generation recombinant inbred lines (RILs), derived from IS22380 (susceptible) × E36-1 (resistant), along with parents were
phenotyped in sick plots at two locations (Dharwad and Bijapur, Karnataka, India). A total of 85 polymorphic marker loci (62
nuclear and 4 genic SSRs, 19 RAPDs) was available for the construction of genetic map, spanning 650.3 cM in all the ten linkage
groups. Analysis with QTL Cartographer (2.5b), adopting composite interval mapping method (LOD > 2.0) at both locations, revealed
5 QTLs at Dharwad and 4 QTLs at Bijapur locations for the component traits of charcoal rot disease resistance. QTLs for number
of internodes crossed, length of infection and per cent lodging accounted for 31.83, 10.76 and 18.90 per cent at Dharwad location
and 14.87, 10.47 and 26.44 per cent phenotypic variability at Bijapur location, respectively. The QTLs for number of internodes
crossed by the rot, length of infection and percent lodging were common across two locations. These QTLs, consistent over
environments for the component traits, are likely to assist in marker-assisted selection (MAS) for charcoal rot resistance
in sorghum. 相似文献
84.
85.
Senthil Arun Kumar Marie Magnusson Leigh C. Ward Nicholas A. Paul Lindsay Brown 《Marine drugs》2015,13(2):788-805
Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO) and Derbesia tenuissima (DT), in a rat model of human metabolic syndrome. Male Wistar rats (330–340 g) were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium. 相似文献
86.
A study was conducted to investigate the effects of paclobutrazol (PBZ) on ion leakage (IL), proline content and activities of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) of 1-year-old ‘Olour’ mango plants subjected to NaCl stress. Plants were treated with two levels of salt, i.e., 0.0 g NaCl (control) and 25 g NaCl/25 kg soil and three levels of paclobutrazol (PBZ) solution (0.0 (control), 750 and 1500 mg/l). Ion leakage, proline content and activities of antioxidant enzymes were significantly altered by both salinity and PBZ treatments. Results indicated that PBZ (1500 mg/l) mitigated the salinity stress and reduced ion leakage of mango seedlings by 64% over non-PBZ-treated salinised plants. PBZ upregulated the endogenous proline content and salinised plants treated with PBZ (1500 mg/l) had 17% higher proline content than salinised plants without PBZ treatment. Higher antioxidant enzyme activity was also observed in salinised plants treated by PBZ than salinised plants without PBZ treatments. Moreover, higher dose of PBZ (1500 mg/l) resulted in higher activity of these enzymes in mango leaves. In comparison to salinised plants without PBZ treatment, salinised plants treated with PBZ (1500 mg/l) had higher SOD (24%), CAT (46%) and POD (163%) activities. Our results suggest that PBZ application under salt stress conditions alters the equilibrium between free radical production and enzymatic defense reactions in mango by enhancing the proline content and free radical scavenging capacity. 相似文献
87.
Wei-An Lai P. D. Rekha A. B. Arun Chiu-Chung Young 《Biology and Fertility of Soils》2008,45(2):155-164
Benefits from the application of plant growth-promoting bacteria in agriculture largely depend on the complex interactions
between several factors including the nature of fertilizers selected. This study was designed to determine the fine tuning
between the inoculated bacteria and different fertilizers and their effect on the growth of lettuce plants (Lactuca sativa L.). Plant growth promotion by a novel species of the genus Azospirillum, namely A. rugosum IMMIB AFH-6, was tested by biochemical, bioassay, and greenhouse studies. The treatments used in the greenhouse study were;
unfertilized control (Blank), half recommended dose of chemical fertilizer (1/2CF), full recommended dose of chemical fertilizer
(1CF), pig manure fertilizer (PMF), pig manure fertilizer + half recommended dose of chemical fertilizer (PMF + 1/2CF), and
pig manure fertilizer + full recommended dose of chemical fertilizer (PMF + 1CF). All these treatments when inoculated with
A. rugosum IMMIB AFH-6 inoculation were, respectively, In-Blank, In-1/2CF, In-1CF, In-PMF, In-PMF + 1/2CF, and In-PMF + 1CF. Significant
increase in plant biomass and shoot N, P, Ca, and Fe was shown in the In-Blank treatment. Plant growth in soil amended with
PMF and A. rugosum IMMIB AFH-6 was significantly lower than in soil treated with the chemical fertilizer, but inoculation combined with chemical
fertilizer significantly elevated the plant biomass. The In-PMF + 1/2CF treatment showed the highest yield. A. rugosum IMMIB AFH-6 facilitated the accumulation of trace minerals in higher concentrations when PMF was combined with 1CF. To examine
the benefits of inoculation by A. rugosum IMMIB AFH-6, we have proposed a new type of data analysis which considers both biomass and nutrient content of plants. This
new type of analysis has shown the importance of the mineral content of plant. 相似文献
88.
A tumor-like tissue mass of lateral-limbal site in the right eye of a 12-year-old Cob Pony mare was presented for surgical removal. The mass, covering the lateral limbus, bulbar conjunctiva and part of the cornea, was surgically removed, and the corneal defect repaired with a pedicle bulbar conjunctival graft. The mass was inflammatory in nature containing mononuclear cells. No recurrence or complication occurred at 6- and 12-month follow-up examination. 相似文献
89.
M. Arun R. Radhakrishnan T.N. Ai A.H. Naing I.J. Lee 《The Journal of Horticultural Science and Biotechnology》2016,91(6):562-572
This study aimed to determine ways to improve the growth and salt tolerance of petunia. Effects of polyamines (PAs; spermidine [Spd], spermine [Spm], and putrescine [Put]) and a nitric oxide (NO) donor (sodium nitroprusside [SNP]) were investigated. Initially, we screened petunia cultivars against sodium chloride (0–125 mM). The petunia cultivar Hurrah Red was identified as salt-sensitive cultivar in the basis of salt-effect on seed germination, fresh weight, and root length of seedlings. Treatment of Hurrah Red shoots with nitrogenous compounds improved the number, length, and fresh weight of roots, as well as the length and fresh weight of shoots over those of the control. Furthermore, plantlets rooted in an optimal concentration of Spd (34.5 µM), Spm (24.8 µM), Put (62.1 µM), and SNP (3.9 µM) were treated with 200 mM NaCl for 3 days to assess their tolerance level. Salt-affected plantlets showed higher level of lipid peroxidation, reduced catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO) activities and decreased contents of photosynthetic pigments and polyphenol than those of the control. PAs and SNP treatments significantly elevated photosynthetic pigments, enhanced antioxidant enzymes, and decreased lipid peroxidation in salt-stressed plantlets. Moreover, the growth and salt-tolerance response of petunia was highest when plantlets were exposed to SNP, followed by levels on treatment with Put, Spm, and Spd. Thus, the findings of this study suggested that treatment with exogenous SNP, Put, Spm, and Spd could protect petunia plants against soil salinity and improve their commercial production. 相似文献
90.
Tomoyuki Suzuki Kritapon Sommart Wanna Angthong Thu Van Nguyen Anan Chaokaur Peerapot Nitipot Arun Phromloungsri Yimin Cai Takashi Sakai Takehiro Nishida Fuminori Terada Tomoyuki Kawashima 《Animal Science Journal》2018,89(9):1287-1295
We conducted a meta‐data analysis to develop prediction equations to estimate enteric methane (CH4) emission from beef cattle in Southeast Asia. The dataset was obtained from 25 studies, which included 332 individual observations on nutrient intakes, digestibilities, and CH4 emissions. Cattle were provided tropical forage or rice straw, with or without concentrates in individual pens equipped with indirect open‐circuit head hood apparatus. The simplest and best equation to predict daily CH4 emission was CH4 (g/day) = 22.71 (±1.008) × dry matter intake (DMI, kg/day) + 8.91 (±10.896) [R2 = 0.77; root mean square error (RMSE) = 19.363 g/day]. The best equation to predict CH4 energy as a proportion of gross energy intake (CH4‐E/GEI, J/100 J) was obtained using DMI per body weight (DMIBW, kg/100 kg), content (g/100 g DM) of ether extract (EE) and crude protein (CP), and DM digestibility (DMD, g/100 g); CH4‐E/GEI = ?0.782 (±0.2526) DMIBW ? 0.436 (±0.0548) EE ? 0.073 (±0.0218) CP + 0.049 (±0.0097) DMD + 8.654 (±0.6517) (R2 = 0.39; RMSE = 1.3479 J/100 J GEI). It was indicated that CH4 emissions from beef cattle in Southeast Asia are predictable using present developed models including simple indices. 相似文献