Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Optimum strip width increases dry matter, nutrient accumulation, and seed yield of intercrops under the relay intercropping system
    Raza, Muhammad Ali ; Feng, Ling Yang ; Werf, Wopke van der; Iqbal, Nasir ; Khan, Imran ; Khan, Ahsin ; Din, Atta Mohi Ud ; Naeem, Muhammd ; Meraj, Tehseen Ahmad ; Hassan, Muhammad Jawad ; Khan, Aaqil ; Lu, Feng Zhi ; Liu, Xin ; Ahmed, Mukhtar ; Yang, Feng ; Yang, Wenyu - \ 2020
    Food and Energy Security 9 (2020)2. - ISSN 2048-3694
    competition ratio - growing space - maize - relay intercropping - soybean

    Strip width management is a critical factor for producing higher crop yields in relay intercropping systems. A 2-year field experiment was carried out during 2012 and 2013 to evaluate the effects of different strip width treatments on dry-matter production, major-nutrient (nitrogen, phosphorus, and potassium) uptake, and competition parameters of soybean and maize in relay intercropping system. The strip width (SW) treatments were 0.40, 0.40, and 0.40 m (SW1); 0.40, 0.40, and 0.50 m (SW2); 0.40, 0.40, and 0.60 m (SW3); and 0.40, 0.40, and 0.70 m (SW4) for soybean row spacing, maize row spacing, and spacing between soybean and maize rows, respectively. As compared to sole maize (SM) and sole soybean (SS), relay-intercropped maize and soybean accumulated lower quantities of nitrogen, phosphorus, and potassium in all treatments. However, maize in SW1 accumulated higher nitrogen, phosphorus, and potassium than SW4 (9%, 9%, and 8% for nitrogen, phosphorus, and potassium, respectively). Soybean in SW3 accumulated 25% higher nitrogen, 33% higher phosphorus, and 24% higher potassium than in SW1. The improved nutrient accumulation in SW3 significantly increased the soybean dry matter by 19%, but slightly decreased the maize dry matter by 6% compared to SW1. Similarly, SW3 increased the competition ratio value of soybean (by 151%), but it reduced the competition ratio value of maize (by 171%) compared to SW1. On average, in SW3, relay-cropped soybean produced 84% of SS seed yield and maize produced 98% of SM seed yield and achieved the land equivalent ratio of 1.8, demonstrating the highest level in the world. Overall, these results suggested that by selecting the appropriate strip width (SW3; 0.40 m for soybean row spacing, 0.40 m maize row spacing, and 0.60 m spacing between soybean and maize rows), we can increase the nutrient uptake (especially nitrogen, phosphorus, and potassium), dry-matter accumulation, and seed yields of relay-intercrop species under relay intercropping systems.

    Chemical composition, ruminal degradation kinetics and methane production (In vitro) potential of local and exotic grass species grown in Peshawar
    Khan, Nazir Ahmad ; Rahman, Sadeeq U.R. ; Cone, John W. - \ 2020
    Pakistan Journal of Botany 52 (2020)1. - ISSN 0556-3321 - p. 161 - 166.
    In vitro gas production - Methane emission - Nutritive value - Rumen fermentation - Tropical grass species

    Livestock production, and small scale and extensive grazing livestock production systems in Pakistan lack long-term sustainability due to declining quantity and quality of green forages and pastures. Information on the nutritional value of range/pasture and cultivated grass species is required to design proper strategies not only for nutritional management of grazing animals, but also for development of good quality forage resources. Therefore, the current study was planned to: (i) analyze the chemical profile of traditional and novel grasses grown in Peshawar; (ii) quantify the methane emission potential of the grass species; and (iii) quantify the differences among species in thei r nutritive value and methane emission. Ten grass species, namely, Sudex (Sorghum × sudangrass), Jumbo grass (Sorghum bicolour× Sorghum sudanefe), Sorghum almum, Pennisetum purpureum, Vetiveria zizanioides, Panicum colaratum, Cynodon dactylon, Bothriochloa pertusa, Splenda setaria and Desmostachya bipinnata were evaluated under uniform agronomic and environmental conditions. The results showed that the contents of all measured chemical components, mineral profile (except Zn), In vitro digestibility of dry matter (DMD), and In vitro gas (GP) and methane-production had large variation among the grass species. Among the grasses, Jumbo grass had greater CP (11.9% DM) content and In vitro DMD (65.9% DM), and produced greater amount of total gas, that contained lowest proportion of methane. In contrast, D. bipinnata had lowest contents of CP (6.3% DM) and In vitro DMD (43.7% DM), and produced lower amount of total gas, with highest proportion methane in total GP. Next to D. bipinnata, V. zizanioides had lower degradability/GP and highest proportion of methane in total gas. The large variation in chemical composition, DMD and methane-emission potential of the summer grass species presents a prospect to select and further develop grass species that have lower methane-emission potential and high nutritional value. Further research is needed to investigate the changes in chemical profile, DMD and methane-emission of forage species between seasons and with maturity.

    Automatic Detection of Tulip Breaking Virus (TBV) Using a Deep Convolutional Neural Network
    Polder, Gerrit ; Westeringh, Nick Van De ; Kool, Janne ; Khan, Haris Ahmad ; Kootstra, Gert ; Nieuwenhuizen, Ard - \ 2019
    IFAC-PapersOnLine 52 (2019)30. - ISSN 2405-8963 - p. 12 - 17.
    Tulip crop production in the Netherlands suffers from severe economic losses caused by virus diseases such as the Tulip Breaking Virus (TBV). Infected plants which can spread the disease by aphids must be removed from the field as soon as possible. As the availability of human experts for visual inspection in the field is limited, there is an urgent need for a rapid, automated and objective method of screening. From 2009-2012, we developed an automatic machine-vision-based system, using classical machine-learning algorithms. In 2012, the experiment conducted a tulip field planted at production density of 100 and 125 plants per square meter, resulting in images with overlapping plants. Experiments based on multispectral images resulted in scores that approached results obtained by experienced crop experts. The method, however, needed to be tuned specifically for each of the data trails, and a NIR band was needed for background segmentation. Recent developments in artificial intelligence and specifically in the area of convolutional neural networks, allow the development of more generic solutions for the detection of TBV. In this study, a Faster R-CNN network is applied on part of the data from the 2012 experiment. The outcomes show that the results are almost the same compared to the previous method using only RGB data.
    Narrow-wide-row planting pattern increases the radiation use efficiency and seed yield of intercrop species in relay-intercropping system
    Raza, Muhammad Ali ; Feng, Ling Yang ; Werf, Wopke van der; Cai, Gao Ren ; Khalid, Muhammad Hayder Bin ; Iqbal, Nasir ; Hassan, Muhammad Jawad ; Meraj, Tehseen Ahmad ; Naeem, Muhammd ; Khan, Imran ; Ur Rehman, Sana ; Ansar, Muhammad ; Ahmed, Mukhtar ; Yang, Feng ; Yang, Wenyu - \ 2019
    Food and Energy Security 8 (2019)3. - ISSN 2048-3694
    competition - intercropping - land equivalent ratio - radiation use efficiency

    Planting arrangements affect radiation use efficiency (RUE) and competitiveness of intercrop species in intercropping systems. Here, we reveal that narrow-wide-row planting arrangement in maize-soybean relay-intercropping system increases the dry matter and competitiveness of soybean, increased the RUE of maize and soybean, and compensates the yield loss of maize by substantially increasing the yield of soybean. In this field study, maize was planted with soybean in different planting arrangements (P1, 20:180, P2, 40:160; P3, 60:140, and P4, 80:120) of relay intercropping, all the relay-intercropping treatments were compared with sole crops of maize (SM) and soybean (SS). Results showed that P1 improved the total RUE 3.26 g/MJ (maize RUE + soybean RUE) of maize and soybean in relay-intercropping system. Compared to P4, treatment P1 increased the soybean competition ratio (CR) values (by 55%) but reduced the maize CR values (by 29%), which in turn significantly improved the yield of soybean by maintaining the maize yield. Generally, in P1, soybean produced 82% of SS yield, and maize produced 88% of SM yield, and it achieved the land equivalent ratio of 1.7. These results suggest that by maintaining the appropriate planting distances between maize and soybean we can improve the competitiveness and yield of intercrop species in relay-intercropping system.

    Multispectral camera as spatio-spectrophotometer under uncontrolled illumination
    Khan, Haris Ahmad ; Thomas, Jean Baptiste ; Hardeberg, Jon Yngve ; Laligant, Olivier - \ 2019
    Optics Express 27 (2019)2. - ISSN 1094-4087 - p. 1051 - 1070.

    Multispectral constancy enables the illuminant invariant representation of multispectral data. This article proposes an experimental investigation of multispectral constancy through the use of multispectral camera as a spectrophotometer for the reconstruction of surface reflectance. Three images with varying illuminations are captured and the spectra of material surfaces is reconstructed. The acquired images are transformed into canonical representation through the use of diagonal transform and spectral adaptation transform. Experimental results show that use of multispectral constancy is beneficial for both filter-wheel and snapshot multispectral cameras. The proposed concept is robust to errors in illuminant estimation and is able to perform well with linear spectral reconstruction method. This work makes us one step closer to the use of multispectral imaging for computer vision.

    Input Selection of Wavelet-Coupled Neural Network Models for Rainfall-Runoff Modelling
    Shoaib, Muhammad ; Shamseldin, Asaad Y. ; Khan, Sher ; Sultan, Muhammad ; Ahmad, Fiaz ; Sultan, Tahir ; Dahri, Zakir Hussain ; Ali, Irfan - \ 2019
    Water Resources Management 33 (2019)3. - ISSN 0920-4741 - p. 955 - 973.
    Artificial neural network - Discrete wavelet transformation - Rainfall-runoff modelling - Wavelet sub-series

    The use of wavelet-coupled data-driven models is increasing in the field of hydrological modelling. However, wavelet-coupled artificial neural network (ANN) models inherit the disadvantages of containing more complex structure and enhanced simulation time as a result of use of increased multiple input sub-series obtained by the wavelet transformation (WT). So, the identification of dominant wavelet sub-series containing significant information regarding the hydrological system and subsequent use of those dominant sub-series only as input is crucial for the development of wavelet-coupled ANN models. This study is therefore conducted to evaluate various approaches for selection of dominant wavelet sub-series and their effect on other critical issues of suitable wavelet function, decomposition level and input vector for the development of wavelet-coupled rainfall-runoff models. Four different approaches to identify dominant wavelet sub-series, ten different wavelet functions, nine decomposition levels, and five different input vectors are considered in the present study. Out of four tested approaches, the study advocates the use of relative weight analysis (RWA) for the selection of dominant input wavelet sub-series in the development of wavelet-coupled models. The db8 and the dmey (Discrete approximation of Meyer) wavelet functions at level nine were found to provide the best performance with the RWA approach.

    Adjustment of measurement errors to reconcile precipitation distribution in the high-altitude Indus basin
    Dahri, Zakir Hussain ; Moors, Eddy ; Ludwig, Fulco ; Ahmad, Shakil ; Khan, Asif ; Ali, Irfan ; Kabat, Pavel - \ 2018
    International Journal of Climatology 38 (2018)10. - ISSN 0899-8418 - p. 3842 - 3860.
    Bias correction of precipitation - High-altitude Indus basin - Net mass balance contribution to river run-off - Net snow accumulation adjustments - Precipitation distribution - Precipitation measurement errors
    Precipitation in the high-altitude Indus basin governs its renewable water resources affecting water, energy and food securities. However, reliable estimates of precipitation climatology and associated hydrological implications are seriously constrained by the quality of observed data. As such, quantitative and spatio-temporal distributions of precipitation estimated by previous studies in the study area are highly contrasting and uncertain. Generally, scarcity and biased distribution of observed data at the higher altitudes and measurement errors in precipitation observations are the primary causes of such uncertainties. In this study, we integrated precipitation data of 307 observatories with the net snow accumulations estimated through mass balance studies at 21 major glacier zones. Precipitation observations are adjusted for measurement errors using the guidelines and standard methods developed under the WMO's international precipitation measurement intercomparisons, while net snow accumulations are adjusted for ablation losses using standard ablation gradients. The results showed more significant increases in precipitation of individual stations located at higher altitudes during winter months, which are consistent with previous studies. Spatial interpolation of unadjusted precipitation observations and net snow accumulations at monthly scale indicated significant improvements in the quantitative and spatio-temporal distribution of precipitation over the unadjusted case and previous studies. Adjustment of river flows revealed only a marginal contribution of net glacier mass balance to river flows. The adjusted precipitation estimates are more consistent with the corresponding adjusted river flows. The study recognized that the higher river flows than the corresponding precipitation estimates by the previous studies are mainly due to underestimated precipitation. The results can be useful for water balance studies and bias correction of gridded precipitation products for the study area.
    Discovering novel Alternaria solani succinate dehydrogenase inhibitors by in silico modeling and virtual screening strategies to combat early blight
    Iftikhar, Sehrish ; Shahid, Ahmad A. ; Halim, Sobia A. ; Wolters, Pieter J. ; Vleeshouwers, Vivianne G.A.A. ; Khan, Ajmal ; Al-Harrasi, Ahmed ; Ahmad, Shahbaz - \ 2017
    Frontiers in Chemistry 5 (2017). - ISSN 2296-2646
    Alternaria solani - Docking and virtual screening - Homology modeling - Pharmacophore modeling - Succinate dehydrogenase
    Alternaria blight is an important foliage disease caused by Alternaria solani. The enzyme Succinate dehydrogenase (SDH) is a potential drug target because of its role in tricarboxylic acid cycle. Hence targeting Alternaria solani SDH enzyme could be efficient tool to design novel fungicides against A. solani. We employed computational methodologies to design new SDH inhibitors using homology modeling; pharmacophore modeling and structure based virtual screening. The three dimensional SDH model showed good stereo-chemical and structural properties. Based on virtual screening results twelve commercially available compounds were purchased and tested in vitro and in vivo. The compounds were found to inhibit mycelial growth of A. solani. Moreover in vitro trials showed that inhibitory effects were enhanced with increase in concentrations. Similarly increased disease control was observed in pre-treated potato tubers. Hence the applied in silico strategy led us to identify novel fungicides.
    Biomonitoring of fluoride pollution with gladiolus in the vicinity of a brick kiln field in Lahore, Pakistan
    Ullah, Kifayat ; Saeed Ahmad, S. ; Nauman Ahmad, M. ; Khan, Sardar ; Urooj, Rabail ; Shahid Iqbal, M. ; Zia, Afia ; Ahmad Khan, N. - \ 2016
    Fluoride 49 (2016)3. - ISSN 0015-4725 - p. 245 - 252.
    Biomonitoring - Brick kilns - Fluoride - Gladiolus - Pakistan - South Asia

    Although there are thousands of small-scale, poorly regulated brick kilns in rural areas of South Asia their impact on local agricultural crops is largely unknown. The impact of fluoride on crops in a brick kiln area in the Northern Punjab Region of Pakistan was investigated. Fluoride accumulation, leaf necrosis, and reduced corm diameter and weight were found in the brick kiln area in two cultivars of Gladiolus that have been widely used as biomonitors in Europe. The rate of increase in leaf injury of the sensitive Gladiolus cultivar was greatest at all sites when the temperature was lower and there was a high relative humidity of 60–75%. The necrotic leaf tip lengths of the indicator plants correlated very well with their fluoride concentrations. The fluoride accumulation was directly proportional to the Fluoride Injury Index, although a higher injury index was observed with the fluoride-sensitive cultivar Lavendell Puff compared to the fluoride-tolerant cultivar Flower Song. These results suggest that injury to sensitive crops from fluoride may occur in other brick kiln areas in South Asia, and that Gladiolus plants could be used as a cost-effective biomonitor for further investigation in this region.

    Burden of diarrhea in the eastern mediterranean region, 1990-2013 : Findings from the global burden of disease study 2013
    Khalil, Ibrahim ; Colombara, Danny V. ; Forouzanfar, Mohammad Hossein ; Troeger, Christopher ; Daoud, Farah ; Moradi-Lakeh, Maziar ; Bcheraoui, Charbel El; Rao, Puja C. ; Afshin, Ashkan ; Charara, Raghid ; Abate, Kalkidan Hassen ; Abd El Razek, Mohammed Magdy ; Abd-Allah, Foad ; Abu-Elyazeed, Remon ; Kiadaliri, Aliasghar Ahmad ; Akanda, Ali Shafqat ; Akseer, Nadia ; Alam, Khurshid ; Alasfoor, Deena ; Ali, Raghib ; AlMazroa, Mohammad A. ; Alomari, Mahmoud A. ; Salem Al-Raddadi, Rajaa Mohammad ; Alsharif, Ubai ; Alsowaidi, Shirina ; Altirkawi, Khalid A. ; Alvis-Guzman, Nelson ; Ammar, Walid ; Antonio, Carl Abelardo T. ; Asayesh, Hamid ; Asghar, Rana Jawad ; Atique, Suleman ; Awasthi, Ashish ; Bacha, Umar ; Badawi, Alaa ; Barac, Aleksandra ; Bedi, Neeraj ; Bekele, Tolesa ; Bensenor, Isabela M. ; Betsu, Balem Demtsu ; Bhutta, Zulfiqar ; Abdulhak, Aref A. Bin; Butt, Zahid A. ; Danawi, Hadi ; Dubey, Manisha ; Endries, Aman Yesuf ; Faghmous, Imad M.D.A. ; Farid, Talha ; Farvid, Maryam S. ; Farzadfar, Farshad ; Fereshtehnejad, Seyed Mohammad ; Fischer, Florian ; Anderson Fitchett, Joseph Robert ; Gibney, Katherine B. ; Mohamed Ginawi, Ibrahim Abdelmageem ; Gishu, Melkamu Dedefo ; Gugnani, Harish Chander ; Gupta, Rahul ; Hailu, Gessessew Bugssa ; Hamadeh, Randah Ribhi ; Hamidi, Samer ; Harb, Hilda L. ; Hedayati, Mohammad T. ; Hsairi, Mohamed ; Husseini, Abdullatif ; Jahanmehr, Nader ; Javanbakht, Mehdi ; Beyene, Tariku ; Jonas, Jost B. ; Kasaeian, Amir ; Khader, Yousef Saleh ; Khan, Abdur Rahman ; Khan, Ejaz Ahmad ; Khan, Gulfaraz ; Khoja, Tawfik Ahmed Muthafer ; Kinfu, Yohannes ; Kissoon, Niranjan ; Koyanagi, Ai ; Lal, Aparna ; Abdul Latif, Asma Abdul ; Lunevicius, Raimundas ; Abd El Razek, Hassan Magdy ; Majeed, Azeem ; Malekzadeh, Reza ; Mehari, Alem ; Mekonnen, Alemayehu B. ; Melaku, Yohannes Adama ; Memish, Ziad A. ; Mendoza, Walter ; Misganaw, Awoke ; Ibrahim Mohamed, Layla Abdalla ; Nachega, Jean B. ; Nguyen, Quyen Le ; Nisar, Muhammad Imran ; Peprah, Emmanuel Kwame ; Platts-Mills, James A. ; Pourmalek, Farshad ; Qorbani, Mostafa ; Rafay, Anwar ; Rahimi-Movaghar, Vafa ; Ur Rahman, Sajjad ; Rai, Rajesh Kumar ; Rana, Saleem M. ; Ranabhat, Chhabi L. ; Rao, Sowmya R. ; Refaat, Amany H. ; Riddle, Mark ; Roshandel, Gholamreza ; Ruhago, George Mugambage ; Saleh, Muhammad Muhammad ; Sanabria, Juan R. ; Sawhney, Monika ; Sepanlou, Sadaf G. ; Setegn, Tesfaye ; Sliwa, Karen ; Sreeramareddy, Chandrashekhar T. ; Sykes, Bryan L. ; Tavakkoli, Mohammad ; Tedla, Bemnet Amare ; Terkawi, Abdullah S. ; Ukwaja, Kingsley ; Uthman, Olalekan A. ; Westerman, Ronny ; Wubshet, Mamo ; Yenesew, Muluken A. ; Yonemoto, Naohiro ; Younis, Mustafa Z. ; Zaidi, Zoubida ; Sayed Zaki, Maysaa El; Rabeeah, Abdullah A. Al; Wang, Haidong ; Naghavi, Mohsen ; Vos, Theo ; Lopez, Alan D. ; Murray, Christopher J.L. ; Mokdad, Ali H. - \ 2016
    American Journal of Tropical Medicine and Hygiene 95 (2016)6. - ISSN 0002-9637 - p. 1319 - 1329.

    Diarrheal diseases (DD) are leading causes of disease burden, death, and disability, especially in children in low-income settings. DD can also impact a child's potential livelihood through stunted physical growth, cognitive impairment, and other sequelae. As part of the Global Burden of Disease Study, we estimated DD burden, and the burden attributable to specific risk factors and particular etiologies, in the Eastern Mediterranean Region (EMR) between 1990 and 2013. For both sexes and all ages, we calculated disability-adjusted life years (DALYs), which are the sum of years of life lost and years lived with disability. We estimate that over 125,000 deaths (3.6% of total deaths) were due to DD in the EMR in 2013, with a greater burden of DD in low-and middle-income countries. Diarrhea deaths per 100,000 children under 5 years of age ranged from one (95% uncertainty interval [UI] = 0-1) in Bahrain and Oman to 471 (95% UI = 245-763) in Somalia. The pattern for diarrhea DALYs among those under 5 years of age closely followed that for diarrheal deaths. DALYs per 100,000 ranged from 739 (95% UI = 520-989) in Syria to 40,869 (95% UI = 21,540-65,823) in Somalia. Our results highlighted a highly inequitable burden of DD in EMR, mainly driven by the lack of access to proper resources such as water and sanitation. Our findings will guide preventive and treatment interventions which are based on evidence and which follow the ultimate goal of reducing the DD burden.

    An appraisal of precipitation distribution in the high-altitude catchments of the Indus basin
    Dahri, Zakir Hussain ; Ludwig, Fulco ; Moors, Eddy ; Ahmad, Bashir ; Khan, Asif ; Kabat, Pavel - \ 2016
    Science of the Total Environment 548-549 (2016). - ISSN 0048-9697 - p. 289 - 306.
    Bias correction - Gridded precipitation products - High-altitude areas - Indus basin - Precipitation distribution

    Scarcity of in-situ observations coupled with high orographic influences has prevented a comprehensive assessment of precipitation distribution in the high-altitude catchments of Indus basin. Available data are generally fragmented and scattered with different organizations and mostly cover the valleys. Here, we combine most of the available station data with the indirect precipitation estimates at the accumulation zones of major glaciers to analyse altitudinal dependency of precipitation in the high-altitude Indus basin. The available observations signified the importance of orography in each sub-hydrological basin but could not infer an accurate distribution of precipitation with altitude. We used Kriging with External Drift (KED) interpolation scheme with elevation as a predictor to appraise spatiotemporal distribution of mean monthly, seasonal and annual precipitation for the period of 1998-2012. The KED-based annual precipitation estimates are verified by the corresponding basin-wide observed specific runoffs, which show good agreement. In contrast to earlier studies, our estimates reveal substantially higher precipitation in most of the sub-basins indicating two distinct rainfall maxima; 1st along southern and lower most slopes of Chenab, Jhelum, Indus main and Swat basins, and 2nd around north-west corner of Shyok basin in the central Karakoram. The study demonstrated that the selected gridded precipitation products covering this region are prone to significant errors. In terms of quantitative estimates, ERA-Interim is relatively close to the observations followed by WFDEI and TRMM, while APHRODITE gives highly underestimated precipitation estimates in the study area. Basin-wide seasonal and annual correction factors introduced for each gridded dataset can be useful for lumped hydrological modelling studies, while the estimated precipitation distribution can serve as a basis for bias correction of any gridded precipitation products for the study area.

    Effect of species and harvest maturity on the fatty acids profile of tropical forages
    Khan, N.A. ; Farooq, M.W. ; Ali, M. ; Suleman, M. ; Ahmad, N. ; Sulaiman, S.M. ; Cone, J.W. ; Hendriks, W.H. - \ 2015
    The JAPS 25 (2015)3. - ISSN 1018-7081 - p. 739 - 746.
    neutral detergent fiber - dairy-cows - perennial ryegrass - maize silages - degradation - stability - grass
    The aim of this study was to quantify the fatty acid (FA) content and composition of forages commonly fed to dairy animals in the tropics. Twelve forage species, namely, Trifolium alexandrinum, Cichorium intybus, Hordeum vulgare L., Medicago sativa, Avena sativa, Pennisetum purpureum Setaria anceps, Sorghum almum, Panicum maximum, Rumex nepalensis, Panicum coloratum and Panicum antidotale were evaluated. Each forage species was grown in four replicate plots under standard agronomic conditions, and sampled at early, normal and late stages of maturity. The result of the present study showed that the chemical composition, dry matter digestibility and FA contents varied (P <0.001) among forage species and harvest maturity. Linolenic acid (C18:3n-3), palmitic acid (C16:0) and linoleic acid (C18:2n-6) were the predominant FAs with an average content of 8.65, 3.61 and 2.38 g/kg dry matter (DM), contributing on average to 53%, 22% and 14% of the total measured FAs, respectively. Among the individual FAs, C18:3n-3 had the largest variation ranging from 4.26 to 17.43 g/kg DM at first harvest. The content of C16:0, C18:2n-6 and C18:3n-3 decreased (P <0.001) with maturity, with the largest decrease being observed in C18:3n-3. This study highlights that harvest management is an important tool to manipulate the FA contents and composition within a forage species
    Improving the feeding value of straws with Pleurotus ostreatus
    Khan, N.A. ; Hussain, S. ; Ahmad, N. ; Alam, S. ; Bezabhi, M. ; Hendriks, W.H. ; Yu, P. ; Cone, J.W. - \ 2015
    Animal Production Science 55 (2015)2. - ISSN 1836-0939 - p. 241 - 245.
    chemical-composition - wheat-straw - digestibility - fermentation - diets - fiber
    The high content of lignin in cell walls is the major limiting factor in the digestion and utilisation of cereal crop residues by ruminants. The aim of this study was to evaluate the effectiveness of the white rot fungus, Pleurotus ostreatus (P. ostreatus), to degrade lignin and to enhance the rumen degradability of maize stover, rice straw, wheat straw and their mixture in equal proportion on a dry-matter (DM) basis. Four samples of each substrate were incubated aerobically in triplicate with P. ostreatus for 0 (Control), 21, 28 and 35 days under solid-state conditions (temperature, 24°C; humidity, 70 ± 5%). The changes in chemical composition, DM and nutrient losses, and rumen fermentation characteristics using in vitro DM digestibility (DMD) and the in vitro gas-production (GP) technique were measured. The results showed that incubation with P. ostreatus decreased (P <0.001) the contents of neutral detergent fibre and lignin with a concomitant increase (P <0.001) in the contents of ash and crude protein. The losses of nutrients differed (P <0.001) among the straw types, with rice straw and maize stover showing the largest (P <0.05) lignin degradation compared to wheat and mixed straws. The DMD and 72-h cumulative GP increased (P <0.001) consistently with increasing fungal incubation period and for all substrates the highest values of DMD and GP were measured after 35 days of incubation with P. ostreatus. The lignin degradation was strongly associated with hemicellulose degradation (r = 0.71) across the various straws. Results of the present study demonstrated that incubation of low-quality crop residues with P. ostreatus under solid-state conditions upgrades their feeding value by reducing the content of lignin and increasing the content of crude protein and ruminal degradation.
    A note on Xiphinema inaequale (Khan & Ahmad) and X. saopaolense Khan & Ahmad
    Lamberti, F. ; Loof, P.A.A. - \ 1977
    Nematologia Mediterranea 5 (1977). - ISSN 0391-9749 - p. 109 - 111.
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