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31.
Helmy M. Youssef Martin Mascher Mohammad A. Ayoub Nils Stein Benjamin Kilian Thorsten Schnurbusch 《Genetic Resources and Crop Evolution》2017,64(5):843-853
Many-grained mutants occurring spontaneously among their less well-endowed field mates may have appeared to early farmers as fortunate twists of fate foreboding wealth and abundance. In domesticated barley, the number of kernel rows in spike can be tripled by recessive mutant alleles at the Six-rowed spike 1 (vrs1) locus that abolish the suppression of lateral spikelet fertility. In another barley row-type, so called intermedium-spike (int), lateral floret size is often intermediate between six-and two-rowed types. Phenotypic and sequence analyses of our intermedium-spike collection revealed that other genes can increase the size of florets and even stimulate occasional grain setting in lateral spikelets. Here, we show that a complete six-rowed phenotype occurs in a diverse panel of intermedium-spike barley carrying wildtype Vrs1 in the presence of the Int-c.a allele of the intermedium spike-c (int-c) gene, previously considered only as a modifier of lateral spikelet fertility. Int-c.a-type alleles had arisen before domestication and are associated with the enlargement of lateral florets in wild barley, suggesting that natural selection/evolution acts towards reduced lateral floret size. Since Int-c.a cannot overcome the suppression of lateral florets in the genomic background of wild barleys, we infer the existence of other gene loci, at which novel alleles or allelic combinations were selected for after domestication, to increase grain number of barley independently of Vrs1. 相似文献
32.
Mohammad Wahsha Mandana Nadimi-Goki Claudio Bini 《Journal of Soils and Sediments》2016,16(4):1300-1305
Purpose
The present paper concerns the distribution and mobility of heavy metals (Cu, Pb, Zn and Fe) in the soils of some abandoned mine sites in Italy and their transfer to wild flora.Materials and methods
Soils and plants were sampled from mixed sulphide mine dumps in different parts of Italy, and the concentrations of heavy metals were determined.Results and discussion
The phytoremediation ability of Salix species (Salix eleagnos, Salix purpurea and Salix caprea), Taraxacum officinale and P?lantago major for heavy metals and, in particular, zinc was estimated. The results showed that soils affected by mining activities presented total Zn, Cu, Pb and Fe concentrations above the internationally recommended permissible limits. A highly significant correlation occurred between metal concentrations in soils.Conclusions
The obtained results confirmed the environmental effects of mine waste; exploring wild flora ability to absorb metals, besides metal exploitation, proved a useful tool for planning possible remediation projects.33.
Rachel Pilla Frederic P. Gaschen James W. Barr Erin Olson Julia Honneffer Blake C. Guard Amanda B. Blake Dean Villanueva Mohammad R. Khattab Mustafa K. AlShawaqfeh Jonathan A. Lidbury Jörg M. Steiner Jan S. Suchodolski 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1853-1866
34.
Mohammad Afzal Khan Ahmad Khalil Jafri & Narendra Kumar Chadha 《Aquaculture Research》2004,35(13):1277-1285
Growth, reproductive performance, muscle and egg composition were investigated in grass carp, Ctenopharyngodon idella (Valenciennnes), fed hydrilla or formulated diets with varying protein levels. Five experimental diets, with varying levels (20%, 25%, 30%, 35% and 40%) of crude protein (CP), were used. One of the fish groups was fed hydrilla. Fish (44.1±0.3 cm; 913±9 g) were stocked (20 tank?1) in outdoor concrete tanks (20 × 10 × 1.5 m) in duplicate, and fed to satiation, twice daily, at 09:00 and 17:00 hours for the experimental duration of 360 days. High (P<0.05) weight gain was recorded in fish fed 30% and 35% CP diets. However, values for gonadosomatic index (GSI), egg diameter, relative fecundity (eggs kg?1 body weight), fertilizability and hatchability (%) were comparable (P>0.05) in fish at ≥25% of dietary protein intake. Hydrilla‐fed fish exhibited lower (P<0.05) values for the measured parameters. Crude protein content in muscle increased with dietary protein level. Highest (P<0.05) muscle protein was obtained in fish fed 35% CP diet. Muscle fat was comparable (P>0.05) among fish receiving formulated diets. Ash content was not significantly (P>0.05) different among fish of different dietary groups. Moisture content in fish fed formulated diets, with the exception of 20% CP diet, did not vary significantly (P>0.05). Eggs of fish fed formulated diets contained higher CP and fat contents than those of hydrilla‐fed fish. High (P<0.05) moisture content was noted in the eggs of hydrilla‐fed fish. Ctenopharyngodon idella fed formulated diet, with a minimum of 25% CP, showed better reproductive performance than those fed hydrilla. 相似文献
35.
Hamid Reza Jamalzadeh Maryam Akhundian Milad Kabir Hossein Khara Saeed Hajirezaee 《Aquaculture Research》2014,45(6):1090-1095
In this study, the relationships between the seminal fluid sex steroids sperm quality parameters (i.e. sperm motility and sperm production were investigated in the endangered Caspian brown trout. According to results, the variation of sex steroid concentrations was comparatively high. The seminal fluid levels of 17α‐Hydroxyprogesterone (OHP) had positive correlation with percentage and duration of sperm motility. Similar correlation was found between the seminal fluid concentration of testosterone (T) and estradiol‐17β (E2) with sperm concentration. As well as, there was no significant correlation between progesterone (P) with sperm quality indices. The significant correlation of some steroids i.e. OHP, T and E2 and sperm quality parameters of Caspian brown trout confirms the key role of these steroids in acquisition of the potential of motility during final stage of the maturation. 相似文献
36.
Rajab Mohammad Nazari Mehdi Sohrabnejad & Mohammad Reza Ghomi 《Aquaculture Research》2009,40(9):1083-1088
The objective of this work was to study the relationship between female size (weight) and variables of egg and larval stage of Persian sturgeon Acipenser persicus . In this study, 19 female breeders were captured in Caspian Sea and fertilized by routine methods. Positive significant correlations ( P <0.05) were established between female weight and ovulated eggs per female, time of second mitosis division and volume of yolk-sac at hatching. There was not significant correlation ( r =0.33, P =0.161) between female weight and egg diameter. Female weight was not affected weight of larvae at hatching time ( r =0.37, P =0.119), as well as larval length ( r =−0.14, P =0.558) and larval weight at the end of the experiment (48 hours after first feeding) ( r =0.16, P =0.491). Mortality rate during yolk-sac absorption was higher with increased female weight but their correlation was not significant ( r =0.40, P =0.076). During the first feeding stage, mortality rate was 13.39% and there was no significant correlation between mortality rate in this period and female weight ( r =−0.12, P =0.613). Conclusively, as a result female size influenced fecundity, time of second mitosis division and yolk-sac volume at hatching time without affecting mortality rate during yolk-sac absorption and first feeding stage in Persian sturgeon. Thus, smaller female broods do not cause more mortality than larger ones in larval production and they can be used in reproduction procedure. 相似文献
37.
Polyculture of western white shrimp,Litopenaeus vannamei Boone, 1931 with Grey mullet,Mugil cephalus Linnaeus, 1758 controls external parasites of western white shrimp 下载免费PDF全文
Seyyed Hossein Hosseini Aghuzbeni Saeed Hajirezaee Hossein Khara 《Aquaculture Research》2016,47(9):2983-2988
The main aim of this study was to examine the effects of a polyculture system on the control of the external parasites of western white shrimp, Litopenaeus vannamei. To this end, the western white shrimp postlarvae (PLs) were stocked in nine earthen ponds (600 m2) at a density of 20 PLs m?2 and reared for 4 months. After 40 days of shrimp stocking, Mullets, Mugil cephalus, were stocked at various densities including: control (0 fish/100 m2 pond), treatment 1 (T1: 2 fish/100 m2 pond) and treatment 2 (T2: 4 fish/100 m2 pond). Over the course of the experiment, the external parasites of shrimps were investigated by the preparation of a wet mount from the gill tissue. Based on the obtained results, totally two genera of protozoan parasites, i.e. Zoothamnium sp. and Epistylis sp., were identified over the course of the experiment. In all experimental groups, the incidence and abundance of Zoothamnium sp. was significantly higher than Epistylis sp. (P < 0.05). Also, mean incidence per cent and mean abundance of Zoothamnium sp. and Epistylis sp. were significantly lower in the polyculture treatments (T1 and T2) compared to the monoculture group (control) (P < 0.05). Throughout this experiment, the total organic matter (TOM %) content of the bottom sediments and biological oxygen demand (BOD5 mg L?1) of water samples in the polyculture ponds were significantly lower than the monoculture group (P < 0.05). In contrast, the polyculture ponds had a higher concentration of water dissolved oxygen (O2 mg L?1) compared to the monoculture (P < 0.05). In conclusion, our results show that mullet as a secondary farmed species can reduce indirectly the parasitic pollution of western white shrimp probably through reducing the total organic matters in water and sediments and improving the water quality parameters. 相似文献
38.
Ebrahim Sotoudeh Jamshid Amiri Moghaddam Gholamreza Shahhosseini Mohammad Sadegh Aramli 《Journal of the World Aquaculture Society》2016,47(6):830-842
This experiment was conducted to evaluate the feasibility of gamma‐irradiated soybean meal (SBM) as a dietary ingredient on the performance, body composition, and digestive enzyme activity of Caspian brown trout, Salmo trutta caspius, juveniles. Five isonitrogenous and isoenergetic diets were formulated, in which fish meal was replaced by untreated (untreated SBM), gamma‐ray irradiated at 15 (15ISBM) and 30 (30ISBM) kGy, fermented (FSBM), fermented 15 KGy irradiated soybean meal (FISBM), respectively. Juvenile fish (2.1 ± 0.3 g) were fed with the test diets for 6 wk. Final body weight was significantly affected by dietary SBM treatment with highest values in fish fed FISBM and FSBM (P < 0.05). There were no significant differences in hepatosomatic and visceral indexes, condition factor, and survival among experimental groups (P > 0.05). The carcass proximate composition of lipid and protein in Caspian brown trout in FSBM and FISBM groups was higher than that of other groups. Levels of most whole‐body amino acids were not significantly different among Caspian brown trout fed the five diets. Results of this experiment showed that replacing SBM with FSBM and FISBM in the diet significantly increased the activities of proteolytic enzymes activities (P < 0.05). However, no significant differences were observed in both amylase and lipase activities among dietary treatments. Results of this study indicated that the level of gamma radiation used did not work but fermentation of SBM did increase some growth parameters of Caspian brown trout. 相似文献
39.
Othman Alqaisi O. Assah Ndambi Mohammad Mohi Uddin Torsten Hemme 《Tropical animal health and production》2010,42(6):1063-1071
The development of the dairy industry plays an important role in the economy of Middle Eastern countries. Judged by its growth
rate, the dairy industry is viewed as one of the most progressive food industries in the Middle East. During the early 1970s,
countries established executive programs to promote dairy farming; the major objective was to attain self-sufficiency in milk
production. A massive investment was set up for importing top class cattle, complying with top industry operating standards,
and a simultaneous introduction of the latest technology in processing, packaging, and distributing. Milk production has grown
tremendously at rates of 6.6% and 4.9% in Syria and Saudi Arabia, respectively, between 2002 and 2007, which resulted in these
nations being almost self-sufficient. Regarding Jordan, milk production has not yet met this target. An excessive growth in
the dairy industry is quite noticeable in this region with an expanding capacity for exports. The aim of this study is to
show the most recent trends and future prospects of the dairy industries in Syria, Saudi Arabia, and Jordan. It also attempts
to investigate the drivers for the development of milk production, consumption, and trade in the region. 相似文献
40.
Sayyed Mohammad Hadi Alavi Elham Jorfi Azadeh Hatef Sayyed Abdul Saheb Mortezavi 《Aquaculture Research》2010,41(10):e688-e694
Spermatozoa concentration, ionic composition, osmolality, glucose and total protein contents of seminal plasma and sperm motility were determined in Barbus sharpeyi (Cyprinidae, Teleosotei). Spermatozoa concentration ranged from 9.77 to 20.20 × 109 spermatozoa mL?1. Osmolality (mOsmol kg?1) and ionic contents (mM L?1) of the seminal plasma were 274.5±9.0, 70.0±3.4 Na+, 28.8±0.9 K+, 101.7±3.1 Cl?, 0.9±0.1 Mg2+ and 2.1±0.1 Ca2+ respectively. Total protein and glucose were 5.3±0.2 g L?1 and 76.7±4.3 mM L?1 respectively. Sperm motility was initiated in a hypo‐osmotic condition, composed of either an ionic (KCl or NaCl) or a non‐ionic (sucrose) activation medium. Duration of sperm motility was very short: <2 min after activation in distilled water. Percentage of motile spermatozoa was significantly higher in an activation medium containing NaCl compared with that of distilled water. An activating medium containing NaCl or KCl higher than 150 mM or sucrose higher than 275 mM totally inhibited the activation of sperm motility. Immediately after sperm activation, wave(s) propagated along the flagellum, but waves were restricted to the proximal part of the flagellum (close to the head) at 1 min post activation. Studied characteristics in the present study were compared with those of other cyprinids for understanding inter‐species differences. 相似文献