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21.
Abstract: Stakeholders are an integral part of environmental conflict. Analysing the positions and interests of stakeholders is vital in effective environmental conflict management. This paper reviews the literature related to stakeholders and their dynamics in environmental conflict. It also presents the results of a study relating to a New Zealand transport infrastructure project where the positions and interests of stakeholders have kept on changing during the life of the project. This study plots the changing positions of some of the key stakeholders, towards this project. These stakeholders include a policy manager, a community stakeholder, an environmental stakeholder and a political stakeholder. The paper also analyses the changing positions by identifying and classifying the key drivers for these changes. 相似文献
22.
G. S. Chaturvedi P. K. Aggarwal A. K. Singh M. G. Joshi S. K. Sinha 《Irrigation Science》1981,2(4):225-235
Summary The effect of irrigation on tillering and tiller mortality in varieties of wheat (Triticum aestivum and T. durum), triticale and barley was studied under field conditions. Low temperature in the early stages of growth promoted production of tillers whereas increase in temperature during extension growth phase increased tiller mortality. More than 1000 tillers m–2 were produced with five irrigations but 40% or more died. With limited water availability tiller production was reduced but so was their mortality. Grain yield in wheat and triticale was positively correlated with productive tillers and negatively correlated with the maximum number of tillers produced in wheat and barley grown under limited irrigation conditions. Varieties with a capacity to produce fewer tillers were identified. Some of them proved more stable in yield. No correlation was found between tiller number and grain yield in the frequently irrigated treatment. 相似文献
23.
The importance of reduced tillage in sustainable agriculture is well recognized. Reduced-tillage practices (which may or may
not involve retention of crop residues) and their effects differ from those of conventional tillage in several ways: soil
physical properties; shifts in host–weed competition; soil moisture availability (especially when sowing deeply or under stubble);
and the emergence of pathogen populations that survive on crop residues. There may be a need for genotypes suited to special
forms of mechanization (e.g. direct seeding into residues) and to agronomic conditions such as allelopathy, as well as specific
issues relating to problem soils. This article examines issues and breeding targets for researchers who seek to improve crops
for reduced-tillage systems. Most of the examples used pertain to wheat, but we also refer to other crops. Our primary claim
is that new breeding initiatives are needed to introgress favourable traits into wheat and other crops in areas where reduced
or zero-tillage is being adopted. Key traits include faster emergence, faster decomposition, and the ability to germinate
when deep seeded (so that crops compete with weeds and use available moisture more efficiently). Enhancement of resistance
to new pathogens and insect pests surviving on crop residues must also be given attention. In addition to focusing on new
traits, breeders need to assess germplasm and breeding populations under reduced tillage. Farmer participatory approaches
can also enhance the effectiveness of cultivar development and selection in environments where farmers’ links with technology
providers are weak. Finally, modern breeding tools may also play a substantial role in future efforts to develop adapted crop
genotypes for reduced tillage. 相似文献
24.
Exploring genetic diversity for heat tolerance among lentil (Lens culinaris Medik.) genotypes of variant habitats by simple sequence repeat markers 下载免费PDF全文
Dharmendra Singh Chandan K. Singh Ram Sevak S. Tomar Ashish K. Chaturvedi Divya Shah Arun Kumar Madan Pal 《Plant Breeding》2016,135(2):215-223
The study was carried out to assess genetic diversity among 119 lentil genotypes grown in different habitats for heat tolerance using morpho‐physiological and reproductive traits and SSR markers. High‐temperature stress was applied at seedling (35/33°C) and anthesis stages (35/20°C) to study the effects on morpho‐physiological and reproductive traits under hydroponic condition, which was compared with non‐stressed and stressed field conditions. A set of 209 alleles were identified by 35 SSR markers among the genotypes. Genetic diversity and polymorphism information content values varied between 0.0494–0.859 and 0.0488–0.844, with mean values of 0.606 and 0.563, respectively. Genotypes were clustered into nine groups based on SSR markers. Morpho‐physiological and reproductive traits under heat stress were found to be significantly different among SSR clusters. These findings suggest that heat adaptation is variable among the genotypes and the tolerant materials can be evolved through hybridization using parents from different clusters with diverse mechanisms of heat tolerance. 相似文献
25.
Mei-Hua Hung Arun A. Bhagwath Fo-Ting Shen Rekha P. Devasya Chiu-Chung Young 《Pedobiologia》2005,49(6):36-584
Root-nodulating bacteria were isolated and characterized from seven native shrubby legumes growing in Taiwan. Phenotypic characteristics measured included growth rates in various media, colony morphology, and tolerances to extremes of temperature, salt and pH. The isolates were very diverse phenotypically. Among the 83 isolates that were screened, the majority were fast-growing rhizobia. Twenty eight strains tolerated high concentration of salt (4.5% NaCl) and grew well between temperatures of 37 and 45 °C. The majority of the strains also tolerated extreme pH in their medium from 3.5 to 12. All strains formed nitrogen fixing nodules, and the highest activity was detected in the legume Hedysarum crinita L. PCR restriction fragment length polymorphism (PCR-RFLP) and sequencing of the small subunit ribosomal RNAs revealed that the majority of the isolates belonged to the genera Rhizobium, Bradyrhizobium and Agrobacterium. Only a single strain represented the genus Sinorhizobium. In addition, a strain related to Burkholderia from the β-class of the Proteobacteria (CC-CC-5) was found within nodules of the legume Catenaria caudatum. The study contributes to the understanding of symbiotic nitrogen fixation in selected wild legumes that are native to Taiwan and provides insights into the distribution of nodulating and nitrogen-fixing bacteria from other distinct lineages. 相似文献
26.
Haunshi S Shanmugam M Padhi MK Niranjan M Rajkumar U Reddy MR Panda AK 《Tropical animal health and production》2012,44(5):969-973
The present study was conducted to evaluate two Indian native chicken breeds, namely, Aseel and Kadaknath for fertility, hatchability,
genetic parameters of juvenile growth traits, and semen quality traits at the onset of sexual maturity. The fertility was
similar in Aseel (86.96%) and Kadaknath (85.15%); however, a relatively higher hatchability was observed in Kadaknath (77.94%)
than Aseel (70.74%). Heritability estimates of body weights at 4 weeks of age were almost similar in Aseel (0.37) and Kadaknath
(0.39), while the estimate of body weight at 6 weeks of age was higher in Aseel (0.42) than Kadaknath (0.31). The heritability
estimate of shank length at 6 weeks of age was lower in Aseel (0.16) compared to Kadaknath (0.35). The age at first egg in
the flock was comparable in Aseel (148 days) and Kadaknath (150 days). Aseel breed with significantly (P ≤ 0.001) higher body weight, absolute and relative testes weights had significantly higher semen volume (P ≤ 0.05) and sperm motility (P ≤ 0.01) but had lower seminal plasma cholesterol level (P ≤ 0.05) as compared to Kadaknath. It can be concluded that there is a scope for genetic improvement of these two native breeds
for juvenile growth traits since heritability estimates of these traits were relatively high. 相似文献
27.
Korlipara V. PadmajaBhamidipati V.S.K. Rao Rondla K. ReddyPotula S. Bhaskar Arun K. SinghRachapudi B.N. Prasad 《Industrial Crops and Products》2012,35(1):237-240
A new class of polyol esters were prepared by esterification of 10-undecenoic acid (UDA) with three polyols namely trimethylolpropane (TMP), neopentyl glycol (NPG) and pentaerythritol (PE) in 92-96% yields. The esters were characterized by IR, 1H NMR, HPLC and mass spectral studies. Polyol esters were evaluated for basic lubrication properties and found to be: viscosity at 40 °C, 11.2-36.1 cSt; at 100 °C, 3.2-7.3 cSt; viscosity index (VI), 162-172; pour point +3 to −36 °C; flash point, 254-296 °C. All the three polyol esters synthesized exhibited good thermal stability with TGA onset temperatures above 260 °C. The lubricating properties of the products compared well with polyol esters based on oleic acid. 相似文献
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30.
G. SivanandhanM. Arun S. MayavanM. Rajesh T.S. MariashibuM. Manickavasagam N. SelvarajA. Ganapathi 《Industrial Crops and Products》2012,37(1):124-129
Calli were obtained from leaf, cotyledon and internode explants of in vitro-grown plants of Indian cultivar of Withania somnifera in MS medium supplemented with 2, 4-D (2.0 mg l−1) and Kinetin (0.2 mg l−1). The brown, semi-friable callus (500 mg FW) derived from leaf explants produced higher number of primary adventitious roots (9 roots/callus) in half strength MS medium fortified with IBA (0.5 mg l−1) and NAA (0.1 mg l−1). The primary adventitious roots with an inoculum mass of 15 g FW were cultured for 6 weeks in the same medium for secondary adventitious root proliferation. Elicitation of abiotic elicitor, aluminium chloride at 10 mg l−1 at the end of 4 weeks culture with 4 h exposure time enhanced withanolides productivity. Under similar culture conditions, the biotic elicitor, chitosan at 100 mg l−1 stimulated higher production of all withanolides when compared to aluminium chloride treatment. This is the first report on the use of callus-derived adventitious root culture for the enhanced production of withanolides upon chitosan elicitation. 相似文献