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31.
Md. Samim Hossain Molla Sutkhet Nakasathien Md. Akkas Ali ASMMR Khan Md. Robiul Alam 《Archives of Agronomy and Soil Science》2019,65(7):928-944
Plants have evolved different mechanisms to survive under stress conditions. This field study was conducted to evaluate the influence of nitrogen (N) application on dry biomass allocation and translocation in two maize varieties under short pre-anthesis and prolonged bracketing flowering period of drought. Two maize varieties, ‘Pioneer 30B80? and ‘Suwan 4452? receiving N at 0 (control), 160 (optimal) and 320 (supra-optimal) kg ha?1 were subjected to short pre-anthesis and prolonged bracketing flowering periods of drought. Prolonged bracketing flowering period of drought had more suppressive effect on anthesis-silking interval, dry matter allocation and translocation, leaf greenness, contribution of current assimilates to grain (CCAG), kernel number, kernel weight and kernel yield of two maize varieties than a short pre-anthesis drought. Nitrogen application at optimal level was the best for all traits, except CCAG. The maize variety ‘Pioneer 30B80? performed better under both drought types due to more root xylem vessels of large size and more accumulation of dry matter in leaves and roots than the variety ‘Suwan 4452?. Therefore, the variety ‘Pioneer 30B80? may be planted in drought prone environments and may be used in breeding program aimed at developing drought-tolerant cultivars. 相似文献
32.
Noor Muhammad Gerald Zvobgo Liangbo Fu Jonas Lwalaba Wa Lwalaba 《Journal of plant nutrition》2019,42(5):466-476
In a previous study, we found that the combined addition of Al and Mn in the culture solution could alleviate the inhibition of barley growth by addition of Al or Mn alone. The current experiment was conducted in a greenhouse to investigate the physiological mechanisms of the antagonistic interaction using two barley genotypes, XZ16 (both Al and Mn tolerant) and ZU9 (both Al and Mn sensitive). The treatments consisted of three Al levels (0, 0.1, and 0.5?mM) and three Mn levels (0, 0.2, and 1.0?mM) and their combinations, and a completely randomized block design was used with three replications. The combined treatments had larger plant biomass, lower Al and Mn concentrations and accumulation in plant tissues, lower malondialdehyde content, and higher root ATPases activities, compared with Al or Mn alone treatment. The two genotypes had the similar trend in the antagonistic interaction, with ZU9 being more predominant than XZ16. 相似文献
33.
Yatoo Mohd. Iqbal Parray Oveas Raffiq Mir Muheet Bhat Riyaz Ahmed Malik Hamid Ullah Fazili Mujeeb ur Rehman Qureshi Sabia Mir Masood Salim Yousuf Raja Wasim Tufani Noor Alam Dhama Kuldeep Bashir Shah Tauseef 《Tropical animal health and production》2019,51(8):2127-2137
Tropical Animal Health and Production - Therapeutic management of contagious caprine pleuroneumonia (CCPP) involves mostly the use of oxytetracycline followed by enrofloxacin and rarely tylosin. In... 相似文献
34.
A. Karami A. Christianus Z. Ishak S. C. Courtenay M. A. Syed M. Noor Azlina H. Noorshinah 《Aquaculture International》2010,18(5):851-858
Triploid African catfish (Clarias gariepinus) produced through cold shock 3 min post fertilization were compared to diploid offspring of the same parentage at 66 days
of age. Triploid fish were significantly shorter (11%) and weighed less (18%) than diploids but showed no significant difference
in mortality or cannibalism, which can be an important source of losses under aquaculture conditions. Erythrocytes of triploid
fish were more oval shaped than the normal spherical shape of diploid erythrocytes, were significantly larger (38%) and had
nuclei that were significantly larger (25%) than observed in diploid fish. Erythrocyte morphological characteristics show
potential as an indicator for the detection of triploidy in African catfish. 相似文献
35.
Siti Noor Fatimah Binti Ismail Syarul Nataqain Baharum Shazrul Fazry Chen Fei Low 《Journal of fish diseases》2019,42(12):1761-1772
Discovery of species‐specific interaction between the host and virus has drawn the interest of many researchers to study the evolution of the newly emerged virus. Comparative genome analysis provides insights of the virus functional genome evolution and the underlying mechanisms of virus–host interactions. The analysis of nucleotide composition signified the evolution of nodavirus towards host specialization in a host‐specific mutation manner. GC‐rich genome of betanodavirus was significantly deficient in UpA and UpU dinucleotides composition, whilst the AU‐rich genome of gammanodavirus was deficient in CpG dinucleotide. The capsid of MrNV and PvNV of gammanodavirus retains the highest abundance of adenine and uracil at the second codon position, respectively, which were found to be very distinctive from the other genera. ENC‐GC3 plot inferred the influence of natural selection and mutational pressure in shaping the evolution of MrNV RdRp and capsid, respectively. Furthermore, CAI/eCAI analysis predicts a comparable adaptability of MrNV in squid, Sepia officinalis than its natural host, Macrobrachium rosenbergii. Thus, further study is warranted to investigate the capacity of MrNV replication in S. officinalis owing to its high codon adaptation index. 相似文献
36.
Nor Zulkiply Amalina Zulperi Dzarifah Mohammad Noor Azmai Amal Mohd Termizi Yusof Mohd Zamri‐Saad Nurhidayu Al‐saari Mami Tanaka Sayaka Mino Tomoo Sawabe Md Yasin Ina‐Salwany 《Aquaculture Research》2019,50(11):3202-3210
Vibrio infections are common among marine fish and lead to serious problems in the aquaculture sector. This study reports a recent occurrence of Vibrio species (spp.) isolated from cultured groupers in Peninsular Malaysia using the gyrB and pyrH genes. A total of 147 Vibrio strains were successfully isolated from 77 (64%) groupers using culture method and subjected to gyrB and pyrH sequencing for species identification and confirmation. Results showed that 89% of Vibrio strains were identified and clustered to six groups of Vibrio spp., while 11% were not clustered to any Vibrio spp. using the gyrB sequences. Meanwhile, by analysis of the pyrH sequences all the 147 Vibrio strains (100%) were successfully identified and clustered into 11 groups of Vibrio spp., including the gyrB non‐identified strains. The pyrH gene provides a better resolution for identification of Vibrio spp. compared with the gyrB gene. Thus, the pyrH gene was more suitable for a rapid determination of Vibrio spp. distribution in Peninsular Malaysia. Using the pyrH gene, our study found higher prevalence of Vibrio vulnificus (33%), V. alginolyticus (24%) and V. parahaemolyticus (22%), followed by V. rotiferianus (5%), V. harveyi (3%), V. tubiashii (2%), V. campbellii (2%), V. ponticus (1%), V. diabolicus (1%), V. owensii (1%) and others Vibrio sp. (7%). Thus, the results of this study revealed that the occurrence of pathogenic vibrios among grouper fish is still high in Malaysian aquaculture. In addition, the pyrH gene was proved as a suitable marker for rapid identification of Vibrio species compared with the gyrB gene. 相似文献
37.
Assessment of gut microbiota in different developmental stages of Malaysian Mahseer (Tor tambroides) 下载免费PDF全文
Mohamad Zaimin Mohd Nosi Sharifah Noor Emilia Syed Jamil Fadaak Muhd Danish Daniel Muhammad Shumpei Iehata 《Aquaculture Research》2018,49(9):2977-2987
Malaysian Mahseer (Tor tambroides) has a good prospect for aquaculture because of its high market demand. However, there is a scarce information on gut microbiota associated with Malaysian Mahseer unlike other fish species. Therefore, we constructed and compared gut microbiota in different developmental stages (larval, juvenile, fingerling, yearling, and adult) using culture dependent and PCR‐DGGE fingerprinting technique for better understanding of gut microbiota composition associated with T. tambroides. Culturable gut microbiota composition in all developmental stages were composed of β‐ and γ‐Proteobacteria, and Bacilli. Biodiversity analysis of culturable gut microbiota showed that larval, juvenile, and adult stages have higher diversity than fingerling and yearling stages. Ward's linkage cluster analysis showed that culturable gut microbiota composition in larval and juvenile stages were close to adult stages, whereas fingerling and yearling stage composed same cluster. PCR‐DGGE fingerprinting technique showed that unculturable gut microbiota were constituted by α‐and γ‐Proteobacteria, and Actinobacteria. Ward's linkage cluster analysis showed that unculturable gut microbiota composition in both larval and juvenile stages were distinct from other developmental stages. Our results revealed that gut microbiota composition were varied in different developmental stages of Malaysian Mahseer and continuous shifts of gut microbiota from larval to adult stages. 相似文献
38.
Effects of dietary selenium on growth performance and oxidative stress in juvenile grass carp Ctenopharyngodon idellus 下载免费PDF全文
L.W. Liu X.‐F. Liang J. Li J.G. Fang X.C. Yuan J. Li M.S. Alam 《Aquaculture Nutrition》2018,24(4):1296-1303
An 8‐week feeding trial was conducted to investigate the effect of dietary selenium (Se) on feed intake, weight gain and antioxidant activity in juvenile grass carp (11.2 ± 0.03 g). Six Se levels (0.13, 0.41, 0.56, 1.12, 2.18 and 4.31 mg/kg) of semi‐purified diets were assayed in triplicate. The maximum weight gain, specific growth rate and feed intake were obtained in fish fed with 1.12 mg Se/kg diet. Hepatic glutathione peroxidase activity was markedly increased when dietary Se ≤1.12 mg/kg diet and reached a plateau when dietary Se ≥1.12 mg/kg diet. Hepatic superoxide dismutase and serum catalase activities in juvenile grass carp fed with 0.56, 1.12 and 2.18 mg Se/kg diets were all significantly higher than those in the other groups. The malondialdehyde content in liver and serum was firstly decreased and then increased with increasing dietary Se content, and the lowest content was observed in fish fed with 1.12 mg Se/kg diet. With the increase in Se level, the activities of serum alanine aminotransferase and aspartate aminotransferase were reduced. In addition, serum alkaline phosphatase activity and albumin content were highest in fish fed with 1.12 mg Se/kg diet. This study indicated that both the Se deficiency and excess of Se caused negative effect on the oxidative stress in juvenile grass carp and suggested that the health‐giving concentration of dietary inorganic Se was 1.12 mg/kg diet. Moreover, based on the broken‐line regression analysis of weight gain, the optimal concentration of dietary inorganic Se was 0.83 mg/kg for juvenile grass carp. 相似文献
39.
Pinus gerardiana Wall. is an important nut-producing pine having restricted distribution in the world. It has been observed that natural regeneration in the species is extremely poor or entirely lacking. The species has erratic and infrequent seed years, dormancy-related problems, and slow growth of seedling, which reduces its regeneration process in natural habitats. Therefore, we investigated the effect of growing medium and seed size on germination and seedling growth of the Pinus gerardiana. The seeds were categorized into two sizes, viz, small (<2.35 cm) and large (>2.35 cm) and five growing medium treatments were used, viz, Soil:Sand:FYM; Soil:Sand:Moss:FYM; Soil:Moss:Vermicompost; Soil:Sand:Vermicompost; and Soil:Sand:Moss:Vermicompost, for assessing their impact on germination and seedling growth. It was observed that, among different growing medium treatments, higher germination and seedling growth parameters were recorded, when Soil:Sand:Moss:Vermicompost was used for the study. Between different seed sizes, higher germination and seedling growth were recorded when seed size was large. 相似文献
40.
播期和密度对棉花叶柄和根系硝态氮含量的影响 总被引:2,自引:0,他引:2
为探讨大田棉花氮代谢随播期和密度的变化规律,选用华棉3109(G.hirsutum L.)于2014年在华中农业大学试验农场,采用裂区设计:播期(月-日)(S1,05-30;S2,06-14)为主区,密度(株·m-2)(D1,7.5;D2,9.0;D3,10.5)为副区,研究了硝态氮含量在主茎叶柄和根系的分布特点。结果表明:1)随生育进程推进,叶柄和根系硝态氮含量先升高后降低,初花期最高。2)主茎叶柄硝态氮含量随叶位变化,蕾期、初花期由上而下逐渐降低,第1叶最高;盛花期逐渐增高,第1叶和第4叶最高;不同生育时期棉花叶柄硝态氮含量在叶位间的下降幅度随播期推迟而降低,随密度增加先升高后降低。3)播期和密度对不同生育时期棉花叶柄和根系硝态氮平均含量的交互作用均显著,但播期和密度主效应影响不同:见花施肥前,随推迟播期,棉花叶柄硝态氮平均含量显著降低了42.9%,根系硝态氮平均含量显著升高了12.1%,增加密度对叶柄和根系硝态氮平均含量无显著影响。见花施肥后,随播期的推迟,叶柄硝态氮平均含量无显著性变化,初花期平均为5.05 mg·g-1,盛花期平均为2.62 mg·g-1;而根系硝态氮平均含量,初花期S1S2,盛花期S1S2;随密度增加,D1,D2与D3初花期叶柄和根系硝态氮平均含量均显著降低;盛花期叶柄硝态氮平均含量呈先升高后降低趋势变化,而根系硝态氮平均含量则与初花期相反,呈显著递增趋势。综上所述,晚播高密条件下,见花一次施肥后,推迟播期不改变棉花地上部叶柄硝态氮平均含量水平,适度增加密度有利于棉花叶柄维持较高的硝态氮含量,有利于为叶片氮代谢提供充足的底物。 相似文献