Correction to: Automation in Agriculture by Machine and Deep Learning Techniques: A Review of Recent Developments     

Saleem  Muhammad Hammad  Potgieter  Johan  Arif  Khalid Mahmood 《Precision Agriculture》2021,22(6):2092-2094

Precision Agriculture - A correction to this paper has been published: https://doi.org/10.1007/s11119-021-09824-9  相似文献   

Separation of DNA for molecular markers analysis from leaves of the Vitis vinifera     

Nazhad NR  Solouki M 《Pakistan journal of biological sciences: PJBS》2008,11(11):1436-1442

In the present study, three DNA extraction procedures were examined to determine which might yield DNA from Grape leaves suitable for molecular analysis for RAPD, SSR. AFLP and etc analysis. The three methods examined were: the miniprep procedure and the modified CTAB for difficult species and protocol CTAB. Only the modified CTAB method consistently yielded DNA suitable for Polymerase Chain Reaction (PCR) amplification, regardless of plant growing conditions or leaf age. The quality and quantity of extracted genomic DNA gained from these methods are deliberated by means UV biophotometer, electrophoresis in 1.2% agarose gel and PCR. In this regard, application chosen for young and mature leaves, the most value of qualified DNA, is extracted from fully expanded leave when PVP was added to the extraction buffer. This same procedure also yielded PCR-amplifiable DNA from various other perennial, woody species and from other fruit species such as apple (Malus domestica), cherry (Prunus avium), peach (Prunuspersica), plum (Prunus domestica). DNA yield from this procedure is high (up to 1 mg g(-1) of leaf tissue). DNA is completely digestible with restriction endonucleases and amplifiable in the Polymerase Chain Reaction (PCR).  相似文献   

Urban Concentration and Poverty in Developing Countries          下载免费PDF全文

Khalid Sekkat 《Growth and change》2017,48(3):435-458

We investigate the impacts of urban concentration (share of the population living in large cities) on poverty in developing countries. We use instrumental variables to estimate a system linking urban concentration, growth and urban and rural poverty. The results show that the importance of the population living in (small) cities (less than 0.5 million inhabitants) or very large cities (beyond 5 million inhabitants) has no impact on poverty. The importance of cities of 1 to 5 million inhabitants is poverty reducing. We conclude that developing countries with a large share of the population living in very big cities could reduce poverty by deconcentrating their urbanization toward cities of between 1 and 5 million inhabitants.  相似文献   

Environmental and genotypic effects on bulb development in onion – a review     

Khalid Mahmud Khokhar 《The Journal of Horticultural Science and Biotechnology》2017,92(5):448-454

Environmental and genetic factors influence growth and bulb development of onions by affecting their physiology. Photoperiod plays critical a role in bulb development and determines the suitability of a cultivar for a particular region. Long days and high temperatures promote onion bulbing. Bulbing is regulated more by temperature than photoperiod, as determined by growing degree days. Far-red light promotes bulbing most effectively. High-temperature storage of sets (above 20–25°C) results in increased total bulb yields, while very high temperature (25.5–31°C) or temperature below 0°C depresses yield. Plant density has an impact on bulb size: the higher the plant density the smaller the bulb size. Onion is more sensitive to water stress during bulb formation and enlargement than during the vegetative stage. Nitrogen improves bulb development, but too much nitrogen promotes excessive vegetative growth and delays maturity. Growth hormones (gibberellins and ethrel) promote the growth and development of bulbs. Flowering and bulb formation in onion is regulated by different (Flowering Locus T) FT genes. Two antagonistic FT-like genes regulate bulb formation. AcFT1 promotes bulb formation, while AcFT4 prevents AcFT1 up-regulation and inhibits bulbing. There is a need to link our research with the genetics and physiology of onions, to enhance bulb yield.  相似文献   

Farmer’s Perception of and Factors Influencing Agroforestry Practices in the Indus River Basin,Pakistan     

Muhammad Imran Mahmood  Muhammad Zubair 《Small-Scale Forestry》2020,19(1):107-122

Agroforestry practices of farming communities are investigated in southern Punjab province, Pakistan. It is hypothesized that rural people of this areas are more inclined than elsewhere in the province to practice agroforestry due to greater profitability than cropping. A landholder survey revealed that the majority of farmers are inclined to plant trees on their land. Low accessibility of institutional credit is a constraint for both agroforestry farmers (AF) and non-agroforestry farmers. However, among AF respondents only 24% were found to need credit for agroforestry practice, as against nearly 76% for crop production. Mostly farmers were found to have positive perceptions regarding agroforestry practice, because they understand the multiple benefits from growing trees, compared with cropping where farmers face various constraints, including poor access to credit, natural hazards, and little support from local authorities. Further, effort to sensitize farmers that growing trees has multiple benefits compared to only cultivation of field crops can bring about change in farmer’s perceptions and attitudes in the Indus River basin, resulting in motivation for agroforestry adoption.  相似文献   

Effect of set-size and storage temperature on bolting,bulbing and seed yield in two onion cultivars     

Khalid Mahmud Khokhar 《Scientia Horticulturae》2009

The effects of three set-sizes (12.5, 17.5 and 22.5 mm in diameter) and seven storage temperatures (0, 5, 10, 15, 20, 25 and 30 °C) on bolting, bulbing and seed yield in two onion (Allium cepa L.) cultivars ‘Hygro’ and ‘Delta’ were investigated. The incidence of bolting increased linearly with set-size and curvi-linearly with decreasing storage temperature. Time to inflorescence emergence and floret opening showed a curvi-linear response to storage temperature with the earliest inflorescence emergence and floret opening occurring at 5 °C and the latest at 30 °C for ‘Hygro’ and at 25 °C for ‘Delta’. Seed yield per umbel also showed a curvi-linear response to storage temperature with the lowest seed yield occurring at 30 °C for ‘Hygro’ and at 25 °C for ‘Delta’ and the highest seed yield at 5 °C. For a seed crop, storage of large sets (22.5 mm) of these cultivars at 5 °C for 120 days appeared to be optimum with 5–12% higher seed yield per umbel than that of 90 days storage. Bulb yield showed a curvi-linear response to storage temperature with the highest bulb yield occurring at 25 °C and the lowest at 5 °C.  相似文献   

Silver nitrate and adenine sulphate induced high regeneration frequency in the recalcitrant plant Cosmos bipinnatus using cotyledon explants     

Mahdi Jaberi  Behzad Gharehyazi  Mahmood Khosrowchahli  Ali Sharafi  Nafiseh Aboofazeli 《The Journal of Horticultural Science and Biotechnology》2018,93(2):204-208

Plant regeneration ability was studied in the medicinal-ornamental plant, Cosmos bipinnatus ‘Sonata white’, which is a dicotyledonous recalcitrant plant to shoot induction. Cotyledons were used as sources of explants to investigate plant regeneration. High frequency of direct shoot induction was obtained when BA (5 mg/l) and AgNO₃ (5 mg/l) were used in combination with 20 mg/l adenine sulphate (73.8%) in Murashige and Skoog (MS) medium. The highest shoot number per explant (5.7) was induced on MS medium supplemented with 5 mg/l BA, 5 mg/l AgNO₃, and 40 mg/l adenine. Eight week-old shoots were transferred to root induction media containing MS and half-strength MS medium with different concentration of IBA. The highest rate of root induction (70.8%) was obtained on half-strength MS medium with 1.5 mg/l IBA within four weeks. The plantlets were transferred to pot and kept in the greenhouse condition. Seventy percent of the plantlets successfully acclimatised.

Abbreviations: BA, 6-benzylaminopurine; IBA, Indole-3-butyric acid; MS, Murashige and Skoog; PGRs, plant growth regulators.  相似文献   

Application of coupled liquid chromatography–mass spectrometry in photolysis studies of the herbicide triflusulfuron‐methyl     

Nourrddine Chafik  Mohammed Mansour  Btissam Elamrani  Karl‐Werner Schramm  Antonius Kettrup  M Khalid Elamrani 《Pest management science》2001,57(6):527-530

The photochemical fate of the herbicide triflusulfuron‐methyl in aqueous solution under UV light (λ > 290 nm) was investigated. Nine photoproducts were detected and tentatively identified by LC/MS and LC/MS/MS analysis. The main routes of degradation involve the cleavage and/or contraction of the sulfonylurea bridge with the elimination of sulfur dioxide, which increases the acidity of the reaction medium. On the basis of the results obtained a photodegradation pathway is proposed. © 2001 Society of Chemical Industry  相似文献   

Fixed-time induction of ovulation in camels superovulated by different eCG modalities during the transition period in Egypt     

Marwa Ahmed Khalifa  Sherif Abdel-Razzak Rateb  Khalid Ahmed El-Bahrawy 《Tropical animal health and production》2016,48(4):823-829

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Bacillus subtilis B21 and Bacillus licheniformis B26 improve intestinal health and performance of broiler chickens with Clostridium perfringens‐induced necrotic enteritis     

Bello Bodinga Musa  Yongle Duan  Hayat Khawar  Qingzhu Sun  Zhouzheng Ren  Mohamed Abdalla Elsiddig Mohamed  Imtiaz Hussain Raja Abbasi  Xiaojun Yang 《Journal of animal physiology and animal nutrition》2019,103(4):1039-1049

This study investigated the influence of Bacillus‐based probiotics on performance and intestinal health in broiler challenged with Clostridium perfringens‐induced necrotic enteritis. One‐day‐old Arbor Acre (n = 480) were randomly assigned to four treatments with 10 cages of 12 birds: (a) basal diet negative control (NC), with no probiotics nor antibiotics formulated to contain 2,930 and 3,060 kcal/kg with 24.07 and 15.98% CP, for starter and finisher diet, respectively, (b) basal diet + enramycin (5 mg/kg), an antibiotic growth promoter (AGP); (c) basal diet + Bacillus subtilis B21 at 2 × 10⁹ CFU per g (BS); (d) basal diet + Bacillus licheniformis B26 at 2 × 10⁹ CFU per g (BL); growth performance, intestinal morphology, intestinal lesion scores, short‐chain fatty acids (SCFAs) and mucosal barrier tight junction's (TJ) mRNA expression were assessed. NC‐ and BL‐fed groups showed higher (p = 0.005) average daily feed intake from d1 to d21 than AGP and BS, whereas BS‐ and AGP‐fed groups showed higher average daily weight gain from d22 to d42 and d1 to d42 of age. Higher mortality rate of (12.5%) and lower of (5.5%) were recorded in AGP and NC fed‐groups respectively, lesion score was higher in BS and BL than in AGP, while no lesion was observed in NC group, results revealed higher duodenum and jejunum villus height to crypt depth (VH:CD) compared with NC and BS. Probiotics‐fed groups showed higher total (SCFAs), acetic and butyric acid concentrations at d21 post‐challenge (PC) than other groups. The expression of claudin‐1 was upregulated in duodenum (d7) PC and in jejunum (d7) and (d21) PC in BL group, while at d21 PC, the expression of occludens was higher in jejunum and ileum by AGP and BL. The present study indicated both BS and BL have some similarity with AGP in preventing or partially preventing NE effect in broilers.  相似文献