智能氮肥在干湿交替灌溉下对水稻产量与水分利用率的影响     

王易天  郭相平  Yousef Alhaj Hamoud  曹克文  朱建彬 《节水灌溉》2021,(8):37-41

为探究智能氮肥(pH响应性控释氮肥)在干湿交替灌溉模式下的适宜性,设置3种程度的干湿交替灌溉W1(灌水下限100％饱和含水率)、W2(灌水下限90％饱和含水率)、W3(灌水下限70％饱和含水率),3种施肥形式智能氮肥(SF)、普通无机氮肥(MF)以及不施氮肥(NF)的桶栽试验,分析其对水稻产量及水分利用效率的影响.结果表明:SF×W1处理下下产量最高,为64.84 g/桶,高出常规氮肥21.8％(W1)、13.9％(W2).SF×W1处理下水分生产效最高,为3.17 kg/m3,SF×W2处理下灌水生产率最高,为1.20 kg/m3.智能氮肥在与适度干湿交替灌溉结合下,能达到节水、增产的目的,是实现水稻节水、高产、控肥的有效途径.  相似文献   

Effect of ruminal heating on thyroid function and heat production of cattle     

M K Yousef  W D Robertson  H D Johnson  L Hahn 《Journal of animal science》1968,27(3):677-683

  相似文献   

Nutritive value of sorghum silage for sheep     

Ehsan Sabertanha  Yousef Rouzbehan  Hassan Fazaeli  Javad Rezaei 《Journal of animal physiology and animal nutrition》2021,105(6):1034-1045

This study compared ensiled sorghum (ES) from two varieties (first and second cuts) with corn silage (CS) for chemical analysis, total-tract nutrient digestibility, ruminal variables and blood biochemistry metabolites in sheep. Five experimental silages representing first cut ES var. Pegah (PS1), second cut ES var. Pegah (PS2), first cut ES var. Speedfeed (SS1), second cut ES var. Speedfeed (SS2) and CS were assessed for chemical analysis, silage fermentation and anti-quality compounds. Diets consisted of lucerne hay, silage and a premix (at the ratio of 53.5:46:0.5 on a dry matter [DM] basis). Feed consumption, total-tract nutrient digestibility, microbial nitrogen supply (MNS), ruminal variables and blood biochemistry metabolites were determined in a Latin square design of five periods with five male sheep. Compared to sorghum, CS had lower (p < 0.01) concentrations of ash, water-soluble carbohydrates and crude protein, but higher starch, lignin (sa), non-structural carbohydrates and apparent nutrient digestibility. The measurements of pH, lactic acid, NH₃-N and volatile fatty acids (VFA) confirmed that all silages were well-preserved. The anti-quality compound levels in the silages were below the safe limits for ruminants. No differences were observed in feed consumption (p > 0.05) and total-tract digestibility of DM and nutrients (p > 0.05). Rumen pH, NH₃-N, VFA concentrations and acetate to propionate ratio showed no difference among treatments (p > 0.05). Sheep fed on sorghum silage showed a decrease (p < 0.01) in total protozoa, and particularly in the Entodiniae population. There were no differences in cellulolytic bacteria counts (p > 0.05) among treatments. Urinary N, MNS and blood biochemistry metabolites showed no difference among treatments (p > 0.05). Silages from both cuts of sorghum had comparable total-tract nutrient digestibility to CS, therefore, these varieties could be used as a more drought resilient silage source in the feeding of sheep.  相似文献   

Effects of Stocking Density and Monosex Culture of Freshwater Prawn Macrobrachium rosenbergii on Growth and Production in Concrete Tanks in Saudi Arabia     

Abdul Qayyum  Siddiqui  Yousef S.  Al-Hafedh  Ahmed H.  Al-Harbi Seikh A.  Ali 《Journal of the World Aquaculture Society》1997,28(1):106-112

Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m², grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m² (29.6 9). and lowest at 20 prawns/m² (17.4 g). Total yield increased from 135 g/m² (1,350 kg/ha) at a density of 5 prawns/m² to 261 g/m² (2,610 kg/ha) at density 15/m^z to 245 g/m² (2,450 kg/ha) at 20/m^z. Feed conversion ratios were high and ranged from 3.7 (5 prawns/m²) to 5.6 (20 prawns/m²).
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m² for 112 d, the all-male population had the best growth performance and feed conversion ratio, followed by the mixed-sex and all-female populations. The all-male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m² (1,590 kg/ha); the mixed-sex population had 90% marketable prawns and the yield was 135 g/m^z (1,350 kg/ha); and the all-female population had 75% marketable prawns with an average yield of 108 g/m² (1,080 kgha).  相似文献   

Effects of diet supplementation and body cooling on friesian calves reared in high ambient temperatures in the eastern desert of Egypt     

I. Fayez M. Marai  A. A. Habeeb  A. H. Daader  H. M. Yousef 《Tropical animal health and production》1997,29(4):201-208

  相似文献   

Zur Wirkung von Temperatur und Photoperiode auf die Entwicklung,Ernährung und Eiablage der Raubmilbe Amblyseius swirskii Ath.-Henr. (Acari,Gamasida, Phytoseiidae)     

Dr. Abd el-tawab A. Yousef  A. H. El-keifl  A. M. Metwally 《Journal of pest science》1982,55(7):107-109

Amblyseius swirskii was reared on immature stages ofTetranychus urticae Koch, under 4 temperature and 3 photoperiod regimes. The raise of temperature produced more rapid development and reduced the adult longevity. The mite feeding capacity and fecundity were positively correlated with temperature. At a photoperiod of 16 h the predator developed quicker but it introduced a considerably lower prey consumption and fecundity.  相似文献   

Compatibility of herbicides used in olive orchards with a Metarhizium brunneum strain used for the control of preimaginal stages of tephritids in the soil     

M. Yousef  E. Quesada-Moraga  I. Garrido-Jurado 《Journal of pest science》2015,88(3):605-612

  相似文献   

Production of Induced Secondary Metabolites by a Co-Culture of Sponge-Associated Actinomycetes,Actinokineospora sp. EG49 and Nocardiopsis sp. RV163     

Yousef Dashti  Tanja Grkovic  Usama Ramadan Abdelmohsen  Ute Hentschel  Ronald J. Quinn 《Marine drugs》2014,12(5):3046-3059

Two sponge-derived actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163, were grown in co-culture and the presence of induced metabolites monitored by ¹H NMR. Ten known compounds, including angucycline, diketopiperazine and β-carboline derivatives 1–10, were isolated from the EtOAc extracts of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163. Co-cultivation of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163 induced the biosynthesis of three natural products that were not detected in the single culture of either microorganism, namely N-(2-hydroxyphenyl)-acetamide (11), 1,6-dihydroxyphenazine (12) and 5a,6,11a,12-tetrahydro-5a,11a-dimethyl[1,4]benzoxazino[3,2-b][1,4]benzoxazine (13a). When tested for biological activity against a range of bacteria and parasites, only the phenazine 12 was active against Bacillus sp. P25, Trypanosoma brucei and interestingly, against Actinokineospora sp. EG49. These findings highlight the co-cultivation approach as an effective strategy to access the bioactive secondary metabolites hidden in the genomes of marine actinomycetes.  相似文献   

Nitrogen Deep Placement Combined with Straw Mulch Cultivation Enhances Physiological Traits,Grain Yield and Nitrogen Use Efficiency in Mechanical Pot-Seedling Transplanting Rice     

Li Lin  Zhang Zheng  Tian Hua  Umair Ashraf  Yousef Alhaj Hamoud  Al Aasmi Alaa  Tang Xiangru  Duan Meiyang  Wang Zaiman  Pan Shenggang 《水稻科学》2022,29(1):89

To assess the effects of straw return coupled with deep nitrogen (N) fertilization on grain yield and N use efficiency (NUE) in mechanical pot-seedling transplanting (MPST) rice, the seedlings of two rice cultivars, i.e., Yuxiangyouzhan and Wufengyou 615 transplanted by MPST were applied with N fertilizer at 150 kg/hm² and straw return at 6 t/hm² in early seasons of 2019 and 2020. The experiment comprised of following treatments: CK (no fertilizer and no straw return), MDS (deep N fertilization and straw return), MBS (broadcasting fertilizer and straw return), MD (deep N fertilization without straw return), MB (broadcasting fertilizer without straw return). Results depicted that the MDS treatment significantly increased the rice yield by 41.69%?72.22% due to total above-ground biomass, leaf area index and photosynthesis increased by 54.70%?55.80%, 38.52%?52.17% and 17.89%?28.40%, respectively, compared to the MB treatment. In addition, the MDS treatment enhanced the total N accumulation by 37.74%?43.69%, N recovery efficiency by 141.45%?164.65%, N agronomic efficiency by 121.76%? 134.19%, nitrate reductase by 46.46%?60.86% and glutamine synthetase by 23.56%?31.02%, compared to the MB treatment. The average grain yield and NUE in both years for Yuxiangyouzhan were higher in the MDS treatment than in the MD treatment. Hence, deep N fertilization combined with straw return can be an innovative technique with improved grain yield and NUE in MPST in South China.  相似文献   

Food Production and Water Conservation in a Recirculating Aquaponic System in Saudi Arabia at Different Ratios of Fish Feed to Plants     

Yousef S.  Al-Hafedh  Aftab  Alam  Mohamed Salaheldin  Beltagi 《Journal of the World Aquaculture Society》2008,39(4):510-520

An indoor aquaponic system (i.e., the integration of fish culture with hydroponic plant production in a recirculating setup) was operated for maximizing water reuse and year-round intensive food production (Nile tilapia, Oreochromis niloticus , and leaf lettuce) at different fish feed to plants ratios. The system consisted of a fish culture component, solid removal component, and hydroponic component comprising six long channels with floating styrofoam rafts for holding plants. Fish culture effluents flowed by gravity from the fish culture component to the solid removal component and then to the hydroponic component. Effluents were collected in a sump from which a 1-horsepower in-line pump recirculated the water back to the fish culture tanks at a rate of about 250 L/min. The hydroponic component performed as biofilter and effectively managed the water quality. Fish production was staggered to harvest one of the four fish tanks at regular intervals when fish attained a minimum weight of 250 g. Out of the total eight harvests in 13 mo, net fish production per harvest averaged 33.5 kg/m³ of water with an overall water consumption of 320 L/kg of fish produced along with the production of leaf lettuce at 42 heads/m² of hydroponic surface area. Only 1.4% of the total system water was added daily to compensate the evaporation and transpiration losses. A ratio of 56 g fish feed/m² of hydroponic surface effectively controlled nutrient buildup in the effluents. However, plant density could be decreased from 42 to 25–30 plants/m² to produce a better quality lettuce.  相似文献