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621.
Participatory farmers’ selection of common bean varieties (Phaseolus vulgaris L.) under different production constraints 下载免费PDF全文
Awio Bruno Enid Katungi Nkalubo T. Stanley Mukankusi Clare Malinga G. Maxwell Gibson Paul Rubaihayo Patrick Edema Richard 《Plant Breeding》2018,137(3):283-289
On‐farm evaluation of 15 common bean varieties was undertaken with nine farmer groups under two fertilizer applications levels in four subcounties of Hoima and Rakai districts for two seasons to select farmers’ desired and undesired varieties. Farmers’ votes for acceptance and rejection of varieties at podding stage were converted to a preference index, and analysis of variance was conducted to examine differences in farmers’ preference indices among subcounties and combined across subcounties, seasons, management and gender. Management had no‐significant influence on the way farmers selected varieties in the subcounties. Choice of varieties varied significantly (p ≤ .001) between seasons and gender in the different subcounties. Variety Masindi Yellow Long and Farmers’ seed (Kaduli), and the introduced KATB1 were accepted by farmers due to their medium seed size, desired seed colour and potential of varietal adaptability to their farm conditions. Varieties NABE2, ROBA1 and RWR719 were deselected due to possession of traits less desired in the market. These results demonstrate the need for breeding programmes to involve diverse stakeholders in capturing the diverse traits preferences in varietal development process. 相似文献
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623.
Pharmacokinetics and selected pharmacodynamics of romifidine following low‐dose intravenous administration in combination with exercise to quarter horses 下载免费PDF全文
H. K. Knych S. D. Stanley D. S. McKemie S. J. Steinmetz 《Journal of veterinary pharmacology and therapeutics》2017,40(5):569-574
Romifidine is an alpha‐2 adrenergic agonist used for sedation and analgesia in horses. As it is a prohibited substance, its purported use at low doses in performance horses necessitates further study. The primary goal of the study reported here was to describe the serum concentrations and pharmacokinetics of romifidine following low‐dose administration immediately prior to exercise, utilizing a highly sensitive liquid chromatography–tandem mass spectrometry assay that is currently employed in many drug testing laboratories. An additional objective was to describe changes in heart rate and rhythm following intravenous administration of romifidine followed by exercise. Eight adult Quarter Horses received a single intravenous dose of 5 mg (0.01 mg/kg) romifidine followed by 1 h of exercise. Blood samples were collected and drug concentrations measured at time 0 and at various times up to 72 h. Mean ± SD systemic clearance, steady‐state volume of distribution and terminal elimination half‐life were 34.1 ± 6.06 mL/min/kg and 4.89 ± 1.31 L/kg and 3.09 ± 1.18 h, respectively. Romifidine serum concentrations fell below the LOQ (0.01 ng/mL) and the LOD (0.005 ng/mL) by 24 h postadministration. Heart rate and rhythm appeared unaffected when a low dose of romifidine was administered immediately prior to exercise. 相似文献
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Zvi Mendel Alex Protasov Yonatan Maoz Marcel Maymon Golan Miller Meirav Elazar Stanley Freeman 《Phytoparasitica》2017,45(3):341-359
The polyphagous shot hole borer (PSHB), Euwallacea nr. fornicatus (Coleoptera; Scolytinae) has become a serious threat to the avocado industry and several shade tree species in Israel. Branch wilting and tree mortality is the outcome of PSHB galleries. Understanding the relationship between avocado trees and the PSHB is required for considering management strategies. In Israel, 52 tree species from 26 botanical families were attacked by the PSHB, but only 12 species were suitable for beetle reproduction. All examined avocado cultivars were attacked, but ‘Hass’ most severely. Large and medium diameter avocado branches were more resistant to PSHB, compared to thin branches. Effectively, gallery density increased as branch diameter decreased. Concomitantly, in large and medium diameter branches, extensive sugar exudation occurred and beetle attack rarely progressed to the formation of natal galleries, whereas minimal sugar exudation was observed in thin branches. This was more evident in those that were weakened by repeated attacks followed by successful beetle colonization. PSHB prefers and successfully colonized branches that had been previously attacked by its conspecifics, and reproduction was much higher in these branches, as opposed to initial attacks. Lesion frequencies increased from late spring (April) until late summer (September). Avocado branches at the early stages of beetle colonization may be identified by sugar exudation at the base of the thin branches. The main approach for reducing damage caused by the PSHB is sanitation, achieved by the removal of colonized branches and intact infested pruned slash. 相似文献
628.
Current forest industries in south-western Australia are based on regrowth natural eucalypt forests and Pinus and Eucalyptus spp. plantations, and restricted to areas with >600 mm y?1 annual rainfall. Dryland farming systems have been developed across 20 million ha in a zone with 300–600 mm y?1 annual rainfall and a Mediterranean climate. This zone is beset with land degradation problems, such as salinity and wind erosion, and there has been considerable effort in the last three decades to develop reforestation options to stabilise the landscapes. Traditional forestry approaches using pulp wood or sawlog production in this zone have been limited by unfavourable economics driven by modest tree growth rates, large transport costs to processing and export facilities, and high labour costs. Given that salinity results from a disruption of the landscape water balance, reforestation has represented a major component in attempts to tackle the problem. Issues with reforestation include (1) obtaining sufficient scale of activity to impact watershed water balances, (2) obtaining a hydrological response without displacing farm production and rural communities and (3) gaining payment for non-forest benefits. This paper reviews the approaches that have been used to integrate trees into the dryland farming (300–600 mm y?1 annual rainfall) systems of south-western Australia, and have resulted in at least 113 286 ha of reforestation. These included both traditional (pine and eucalypt sawlogs) and new (sandalwood, biodiversity restoration and carbon mitigation through bioenergy and carbon sequestration) projects. Ongoing investment has centred on carbon sequestration as this represents one of the few profitable options for the management of dryland salinity in this region. Approaches developed in this region to encourage farmland reforestation will be applicable in other dryland regions, particularly with the interest in using the land-sector to meet climate mitigation targets. 相似文献
629.
The effect of the herbicides simazine (2)-chloro-4,6-bis (ethylamino)-s-triazine, ioxynil (4-hydroxy-3,5-diiodobenzonitrile) and 2,3,6-TBA(2, 3,6-trichlorobenzoic acid) on microbial activity and available plant nutrient content of an acid and an alkaline soil during an incubation period of six weeks under aerobic conditions has been studied in comparison with untreated soils. The herbicides were incorporated with the soils at normal application rates. At intervals determinations were made of carbon dioxide liberated, the content of ammonium and nitrate nitrogen and of available mineral plant nutrient elements. These quantities were not significantly influenced by the presence of 2,3,6-TBA :simazine stimulated microbial activity and ioxynil did so after an initial period of suppression. Both simazine and ioxynil retarded nitrification in the alkaline soil but increased it in the acid soil, attributed in part to stimulation of heterotrophic organisms. Biological oxidation of manganese was retarded by ioxynil but stimulated by simazine. Changes in the availability of some other plant nutrient elements were also found. 相似文献
630.
Falkow S 《Science (New York, N.Y.)》2003,300(5620):737-9; author reply 737-9