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961.
Asad Mohammadi Zarejabad Mohammad Ali Jalali Mohammad Sudagar Somayeh Pouralimotlagh 《Fish physiology and biochemistry》2010,36(3):655-659
The effect of environmental salinity on hematological parameters of great sturgeon Huso huso juveniles was studied. Five-month-old juveniles (mean body weight 28.3 ± 2.1 g) were subjected to 0, 3, 6, 9, and 12 ppt
salinities. The hematological parameters were assessed after a period of 20 days rearing at these salinities. After transfer
from fresh water to brackish water, red blood cells, hematocrit, haemoglobin and mean corpuscular haemoglobin decreased, but
mean corpuscular volume increased. Mean corpuscular haemoglobin concentration, white blood cells, monocyte counts, and eosinophil
counts showed no significant variations with increase in environmental salinity. An increase was found in lymphocyte counts
according to the increase of salinity from 0 to 12 ppt, while the fresh water control group maintained basal levels. Decrease
in neutrophil counts was observed in great sturgeon with increase in environmental salinity. These data show significant effect
of salinity on the blood parameters of great sturgeon. 相似文献
962.
Chris Ojiewo Emmanuel Monyo Haile Desmae Ousmane Boukar Clare Mukankusi‐Mugisha Mahendar Thudi Manish K. Pandey Rachit K. Saxena Pooran M. Gaur Sushil K. Chaturvedi Asnake Fikre NPVR Ganga Rao CV SameerKumar Patrick Okori Pasupuleti Janila Jean Claude Rubyogo Chigeza Godfree Essegbemon Akpo Lucky Omoigui Stanley Nkalubo Berhanu Fenta Papias Binagwa Michael Kilango Magdalena Williams Omari Mponda David Okello Mekasha Chichaybelu Amos Miningou Joseph Bationo Dramane Sako Sory Diallo Candidus Echekwu Muhammad Lawan Umar Richard Oteng‐Frimpong Haruna Mohammed Rajeev K. Varshney 《Plant Breeding》2019,138(4):487-499
Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement. 相似文献
963.
豇豆根腐病病原菌鉴定 总被引:1,自引:0,他引:1
正豇豆营养价值较高,且在改善土壤肥力等方面具有重要作用。近年来,由于环境恶劣、栽培管理不当、抗病品种缺乏等原因,使得豇豆根腐病发生严重,现已成为制约豇豆生产的重要土传病害。目前,国内外已报道可引起豇豆根腐病的镰孢菌有11种,如茄病镰孢Fusarium solani、尖孢镰孢F. oxysporum、轮枝镰孢F. verticillioides等(https://nt.ars-grin.gov/fungaldatabases/),但是对茄病镰孢种下专化型 相似文献
964.
Rauf Muhammad Yoon Hyemyeong Lee Sukyeung Shin Myoung-Jae Ko Ho-Cheol Lee Myung-Chul Oh Sejong Hyun Do-Yoon Hur Onsook Choi Yu Mi 《Journal of Crop Science and Biotechnology》2019,22(5):495-507
Journal of Crop Science and Biotechnology - Oat (Avena sativa L.) is one of the world’s most important cereal crops, owing to its use as an important source of essential nutrients for both... 相似文献
965.
966.
Ali MAHDAVI 《干旱区科学》2020,12(5):766-774
Persian oak (Quercus brantii var. persica) is a dominant tree species of Zagros forests in a semi-arid area, western Iran. However, the capacity of biomass and carbon stocks of these forests is not well studied. We selected three types of oak, i.e., seed-originated oak, coppice oak and mixed (seed-originated and coppice) oak of Zagros forests in Dalab valley, Ilam Province, Iran to survey the capacity of biomass and carbon stocks in 2018. Thirty plots with an area of 1000 m2 were systematically and randomly assigned to each type of oak. Quantitative characteristics of trees, such as diameter at breast height (DBH), height, crown diameter and the number of sprouts in each plot were measured. Then, aboveground biomass (AGB), belowground biomass (BGB), aboveground carbon stock (AGCS) and belowground carbon stock (BGCS) of each tree in plots were calculated using allometric equations. The litterfall biomass (LFB) and litterfall carbon stock (LFCS) were measured in a quadrat with 1 m×1 m in each plot. One-way analysis of variance and Duncan's test were performed to detect the differences in biomass and carbon stocks among three types of oak. Results showed that AGB, BGB and BGCS were significantly different among three types of oak. The highest values of AGB, AGCS, BGB and BGCS in seed-originated oak were 76,043.25, 14,725.55, 36,737.79 and 7362.77 kg/hm2, respectively. Also, the highest values of LFB and LFCS in seed-originated oak were 3298.33 and 1520.48 kg/hm2, respectively, which were significantly higher than those of the other two types of oak. The results imply the significant role of seed-originated oak for the regeneration of Zagros forests. Further conservation strategy of seed-originated oak is an important step in the sustainable management of Zagros forests in Iran. 相似文献
967.
968.
A large‐scale survey of Citrus tristeza virus (CTV) was carried out from 2016 to 2018 in the Chlef Valley, one of the main citrus growing areas in Algeria. In this study a total of 1680 citrus trees from 93 commercial orchards were sampled. The collected samples were tested by direct tissue blot immunoassay analysis and by the double antibody sandwich enzyme‐linked immunosorbent assay technique, and 54 trees were identified as being infected with CTV. This result confirmed that 54 trees were infected by the virus, corresponding to an infection rate of 3.21% throughout the studied area. Five of these local CTV sources were chosen for further molecular investigations to determine the genotype associated with the CTV isolates now spreading in the Chlef area. Characterization with multiple molecular markers showed the presence of the T30 and VT genotypes. This result allowed confirmation of the presence of a virulent strain belonging to the VT genotype. The other CTV isolates were similar to those from the Mitidja region, which showed 99% nucleotide identity with the Spanish mild CTV isolate. This early finding of a strain belonging to the VT genotype is an issue for Algerian citrus producers and needs rapid actions to be taken by the National phytosanitary services, extending the surveillance to other citrus production regions and uprooting the infected trees. 相似文献
969.
Journal of Plant Diseases and Protection - The elemental compositions of healthy and infested leaves of three species of lemon trees (Citrus aurantifolia, Citrus aurantium and Citrus medica) were... 相似文献
970.
Ali Serhan Tarkan Gordon H. Copp Grzegorz Zięba Michael J. Godard Julien Cucherousset 《水产资源保护:海洋与淡水生态系统》2009,19(7):797-805
- 1. The crucian carp Carassius carassius is a species of cyprinid fish native to south‐east England, but few studies exist on its growth and reproduction in England, and the species is threatened by introductions of its Asiatic congener, goldfish Carassius auratus. To increase knowledge of the crucian carp as a means of aiding its conservation, the present study assesses the growth (back‐calculated length at age, body condition) and reproduction (fecundity, egg size, length and age at maturity) of crucian carp in small ponds of Epping Forest (north‐east London, England).
- 2. Evaluation of growth and reproduction data with published data for populations from northern Europe (i.e. latitude ?50°) suggest that growth is very variable, even within the same area, and that data on reproductive indices, in particular length and age at maturity, are scarce. In England, the length at age trajectory of crucian carp living in sympatry with feral goldfish Carassius auratus did not differ significantly from allopatric crucian carp populations, but crucian carp body condition and relative fecundity (eggs per body weight) were highest, and mean age and standard length at maturity were lowest in sympatry with goldfish.
- 3. These data suggest that somatic growth and reproductive output may be maximized in crucian carp when confronted by coexistence with feral goldfish. However, the potential impact of goldfish introductions on crucian carp growth and reproduction requires further study, involving a much larger number of crucian carp populations, both in allopatry and sympatry with feral goldfish populations.