Genetic population structure in the Chilean jack mackerel, Trachurus murphyi (Nichols) across the South-eastern Pacific Ocean     

Leyla Crdenas  Andrea X. Silva  Antonios Magoulas  Josefina Cabezas  Elie Poulin  F. Patricio Ojeda 《Fisheries Research》2009,100(2):109-115

The Chilean jack mackerel Trachurus murphyi, is a pelagic fish from the Carangidae family that is distributed in the South Pacific Ocean. Because this species constitutes an important economic resource across the South Pacific and plays an important ecological role in this ecosystem there is a growing interest in determining its population structure. In this study, we used molecular markers (mitochondrial DNA sequences and microsatellites) from Chilean jack mackerel samples to investigate its genetic population structure across the South Pacific Ocean. The mitochondrial DNA did not detect a genetic structure in T. murphyi populations in the Pacific Ocean, but revealed very low haplotype diversity and a short genealogy history compared to other small-pelagic species. The same general pattern of a lack of genetic structure was found with microsatellite loci; however, a large genetic diversity was revealed with microsatellite markers. The present results did not support the existence of different stock units for T. murphyi across the South Pacific Ocean but a more holistic approach will be necessary to determine an adequate management strategy for this fishery.  相似文献   

Amendment of hydroponic nutrient solution with humic acid and glutamic acid in tomato (Lycopersicon esculentum Mill.) culture     

Maryam Haghighi  Jaime A. Teixeira Da Silva 《Soil Science and Plant Nutrition》2013,59(4):642-648

Abstract

Can humic acid (HA) and glutamic acid (GA), when added to tomato (Lycopersicon esculentum Mill. cv. ‘Hongyangli’) nutrient solution in a hydroponic system, improve growth? Tomato seedlings were grown in six nutrient solutions: (1) control (C), (2) C + 25 mg L^?1 HA (HA1); (3) C + 50 mg L^?1 HA (HA2); (4) C + 100 mg L^?1 GA; (5) HA1 + GA; (6) HA2 + GA. Various biochemical and physiological parameters were measured. HA increased photosynthesis rate and mesophyll conductance. HA did not significantly affect transpiration, stomatal conductance, titratable acidity, or antioxidant activity. In addition, GA improved protein and sugar content, mesophyll conductance and yield. The combination of HA and GA was more effective, especially with 50 mg L^?1 HA. The activity of superoxide dismutase (SOD) and peroxidases (POD) did not change in the presence of HA or GA. Malondialdehyde (MDA) content increased by 30% in HA2 together with GA. HA has a positive effect on tomato hydroponic growth when applied with GA. This expands the use of HA and GA for horticultural commodities in hydroponic systems.  相似文献   

Mineral Nutrition Of ‘Petopride’ Processing Tomato Under Partial Rootzone Drying     

Justin B. France  Maryam Haghighi  Amy Watson  Tessa Mills 《Journal of plant nutrition》2014,37(7):1056-1062

Information is scant on the mineral nutrition of plants undergoing partial rootzone drying (PRD). Researchers applied PRD to ‘Petopride’ tomato in a glasshouse by alternating irrigation to one side of the plant with half of the water in control (C). Roots in PRD treatment had higher magnesium (Mg) and copper (Cu) than C roots. Leaves in PRD treatment had lower P and higher K than C leaves. Minerals in leaves of C and PRD were within literature reported sufficiency ranges. Fruit of the PRD treatment had higher nitrogen (N) and zinc (Zn), but lower phosphorus (P), calcium (Ca), manganese (Mn) and boron (B) than C fruit. Mineral nutrition of fruit was most affected by PRD compared to that of leaf and root. Fruit of the PRD treatment had a higher incidence of blossom end rot (BER) than C fruit. Incidence of BER notwithstanding, although PRD affected the mineral nutrition of the tomato plant, there was no evidence that the lower yield in PRD was due to poor mineral nutrition.  相似文献