Competitive ability of some cover crop species against Asystasia gangetica and Pennisetum polystachion     

Batoul Samedani  Abdul Shukor Juraimi  Md. Parvez Anwar  Mohd Yusop Rafii  Sheikh Abdullah Sheikh Awadz  Abudul Rahim Anuar 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):571-582

Abstract

Asystasia gangetica and Pennisetum polystachion are the most troublesome weeds in oil palm plantations in Malaysia and establishment of cover crops under oil palms is an integral part of sustainable weed management in plantations. Replacement-series experiments were conducted to evaluate the mode and strength of competitiveness of four legume cover crop species, Calopogonium caeruleum, Centrosema pubescens, Mucuna bracteata and Pueraria javanica, and one soft grass species, Axonopus compressus, against Asystasia gangetica and Pennisetum polystachion. Relative yield, relative yield total and relative crowding coefficient were calculated with reference to shoot biomass. Asystasia gangetica was a consistently weaker competitor than Pennisetum polystachion. The legume cover crop species had higher relative yield when grown in mixtures, whereas the yield of Asystasia gangetica was lower in mixtures with legumes than in monoculture. The higher competitiveness of legumes was due to greater canopy height and leaf area index. Centrosema pubescens was a slightly weaker competitor than the other legumes. Although leaf area per plant of Centrosema pubescens did not differ from that of other three legumes, canopy height and blocking photosynthetically active radiation to the soil surface were lower. When grown with a cover crop for 12 weeks, dry weight per plant, leaf area and shoot number of Pennisetum polystachion increased as its proportion decreased in mixtures. Relative yield data indicated that Pennisetum polystachion is a strong competitor. Axonopus compressus was less susceptible to Pennisetum polystachion interference than the legumes. All cover crop species studied proved highly competitive against Asystasia gangetica, but none could compete against Pennisetum polystachion. The study confirms the feasibility of using a cover crop for management of Asystasia gangetica.  相似文献   

Prediction of soluble solids content of pineapple via non-invasive low cost visible and shortwave near infrared spectroscopy and artificial neural network     

Kim Seng Chia  Herlina Abdul Rahim  Ruzairi Abdul Rahim 《Biosystems Engineering》2012,113(2):158-165

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Effect of management on reproductive performances of the Achai cattle in the Hindu Kush (Northern Pakistan)     

Saleem M  Rahim IU  Rueff H  Khan M  Khan M  Wiesmann U  Muhammad S 《Tropical animal health and production》2012,44(6):1297-1302

This study evaluates the effect of management on the undocumented Achai cattle reproductive performance in transhumant farming systems (TFS) and in sedentary farming systems (SFS) in northwestern Pakistan. Data were collected from 172 households in TFS and 270 households in SFS to analyze the effect of farming systems, parity, and calving season on key reproductive traits. The results show that farming systems significantly affect pubertal age, while parity has no significant effect on any of the key traits. The calving season significantly affects the postpartum anoestrus interval in TFS only. More than 50% of the cows in both systems have postpartum anoestrus intervals and calving intervals within the recommended values for cows in tropical countries. Achai cows have high first-service conception rates (70% and 71% for TFS and SFS, respectively) and require a relatively small number of services per conception (1.53 ± 0.06 and 1.48 ± 0.05 SE for TFS and SFS, respectively). This local breed thus warrants conservation under both farming systems.  相似文献   

The use of milk progesterone analysis to monitor reproductive activity in the camel (Camelus dromedarius)     

S E Abdel Rahim 《The British veterinary journal》1989,145(1):23-27

Milk progesterone profiles were used to monitor the ovarian changes during the post-partum period of five she-camels. Milk samples were collected daily for 60 days from four suckling camels (1-4) and from one animal whose calf died on day 3. Progesterone was determined using the Ovucheck Bovine progesterone kits. The first increase of progesterone level in the five animals occurred on days 28, 26, 21, 24 and 20 respectively. At least two progesterone peaks of 6 +/- 2 SD days' duration occurred during the 60 days. An early one day peak was also noticed in three animals.  相似文献   

Acceleration of Anthraquinone-Type Dye Removal by White-Rot Fungus Under Optimized Environmental Conditions     

Tony Hadibarata  Abdull Rahim Mohd Yusoff  Risky Ayu Kristanti 《Water, air, and soil pollution》2012,223(8):4669-4677

The decolorization of the recalcitrant dye Remazol Brilliant Blue R (RBBR) by the culture filtrate of Polyporus sp. S133 and the effect of various environmental factors were investigated. Both biodegradation and biosorption were playing an important role in bioremoval mechanisms. The highest biosorption of RBBR in Polyporus sp. S133 was shown by all carbon sources such as sucrose, glucose, fructose, and starch. No biosorption was shown by the addition of aromatic compounds and metal ions; 97.1?% RBBR decolorization was achieved in 120-rpm culture for 96?h, as compared to 49.5?% decolorization in stationary culture. Increasing the shaking rotation of the culture to more than 120?rpm was proven to give a negative effect on decolorization. The highest production of laccase was shown at pH 4 and constantly decreases when the pH level increases. The addition of glucose, ammonium tartrate, Cu²⁺, and protocatechuic acid was the suitable environmental condition for RBBR decolorization. There was a positive relationship between all environmental conditions and laccase production in the decolorization of RBBR.  相似文献   

Economic valuation and conservation: Do people vote for better preservation of Shadegan International Wetland?     

Sara Kaffashi  Mad Nasir Shamsudin  Alias Radam  Mohd Rusli Yacob  Khalid Abdul Rahim  Muhammad Yazid 《Biological conservation》2012,150(1):150-158

Shadegan International Wetland (SIW) is a unique natural ecosystem with great national and international significance, designated under Ramsar Convention. Located in southern part of Iran, this wetland serves many functions. Among them the rich biodiversity, ecological, hydrological, and economic functions are the most important. Despite the great opportunities for sustainable development of this wetland, it is currently under serious threats from a diverse range of non-sustainable activities. Underestimating SIW’s non-market values in development decisions is a major reason for the conversion and excessive depletion of its resources. The aim of this study was therefore to estimate the economic benefit of SIW as a very useful instrument to reflect the values of this unique ecosystem to society members. A choice experiment (CE) survey was undertaken to estimate the value of different nonmarket attributes of SIW. In addition to the overall model, users and nonusers preferences were also estimated. Random parameter logit (RPL) model was employed to derive the marginal value of the respondents for different attributes of the nonmarket values of SIW. Results indicated the respondents’ positive preferences towards better conservation of SIW.  相似文献   

Resistance spectra of wheat genotypes and virulence patterns of <Emphasis Type="Italic">Mycosphaerella graminicola</Emphasis> isolates in Iran     

Masoud Abrinbana  Javad Mozafari  Masoud Shams-bakhsh  Rahim Mehrabi 《Euphytica》2012,186(1):75-90

Co-evolution of wheat and its devastating pathogen Mycosphaerella graminicola (anamorph Septoria tritici), the causal agent of septoria tritici blotch, a foliar disease of wheat, is suggested to occur in Fertile Crescent as their center of origin and, thus, interaction between pathogen virulence and host resistance is important subject to be addressed. We have investigated resistance spectra of 54 wheat genotypes including a set of differentials carrying known resistance genes and virulence patterns of 14 M. graminicola isolates at seedling stage under controlled environmental conditions. The isolates were collected in Iran from five provinces. Diversity in virulence and aggressiveness was observed among the isolates from four provinces. Isolates collected from Golestan province were virulent to all wheat genotypes from germplasm of Iran, while specific resistances were identified to the isolates from other provinces. Among wheat genotypes, cvs. Chamran, Morvarid and Hirmand had the greatest number of specific resistances as well as partial resistance. Wheat genotypes of the differential set also differed in their reactions to the isolates. Arina, Flame and TE 9111 were specifically resistant to the greatest number of isolates from different provinces. Most isolates were virulent to the other differentials such as cvs. Shafir, Estanzuela federal and Courtot indicating that extensive adaption of virulence to most of the known resistance genes (Stb) has occurred in these regions. The new sources of resistance to highly virulent isolates from Iran may also be utilized in wheat breeding programs to develop resistant cultivars against pathogen populations in other countries.  相似文献   

Inheritance of resistance to sunflower downy mildew races 1, 2 and 3 in cultivated sunflower   总被引：1，自引：0，他引：1  

M. Rahim    C. C. Jan  T. J. Gulya 《Plant Breeding》2002,121(1):57-60

Sunflower downy mildew (SDM) caused by Plasmopara halstedii, is a major disease of sunflower. Eleven resistance genes have been identified, but allelic relationships among these genes are not clear. This study examined the inheritance and allelic relationships of genes conferring resistance to SDM races 1, 2 and 3 (virulence phenotypes 100, 300 and 700, respectively) and confirmed a twelfth resistance gene. Three USDA Plant Introductions, AMES 3235, PI 497250, and PI 497938, and three released lines, RHA 266, RHA 274 and DM‐2 were studied. RHA 266 has only the Pl₁ gene for race 1 resistance. Digenic inheritance of resistance was found in AMES 3235, PI 497250, and RHA 274. These lines have the Pl₁ and Pl₁₂ genes, conferring resistance to race 1, and the Pl₂ and Pl₁₁ genes, conferring resistance to race 2. DM‐2 and PI 497938 have Pl₁₂ (but not Pl₁ for resistance to race 1, the Pl₁₂ gene (but not the Pl₂) for resistance to race 2, and Pl₅ for resistance to race 3. These resistance genes will serve as a foundation for future gene designations and genetic diversity studies of resistance to SDM.  相似文献   

Comparing the Soil Conservation Service model with new machine learning algorithms for predicting cumulative infiltration in semi-arid regions     

Khabat KHOSRAVI  Phuong T. T. NGO  Rahim BARZEGAR  John QUILTY  Mohammad T. AALAMI  Dieu T. BUI 《土壤圈》2022,32(5):718-732

Water infiltration into soil is an important process in hydrologic cycle; however, its measurement is difficult, time-consuming and costly. Empirical and physical models have been developed to predict cumulative infiltration (CI), but are often inaccurate. In this study, several novel standalone machine learning algorithms (M5Prime (M5P), decision stump (DS), and sequential minimal optimization (SMO)) and hybrid algorithms based on additive regression (AR) (i.e., AR-M5P, AR-DS, and AR-SMO) and weighted instance handler wrapper (WIHW) (i.e., WIHW-M5P, WIHW-DS, and WIHW-SMO) were developed for CI prediction. The Soil Conservation Service (SCS) model developed by the United States Department of Agriculture (USDA), one of the most popular empirical models to predict CI, was considered as a benchmark. Overall, 154 measurements of CI (explanatory/input variables) were taken from 16 sites in a semi-arid region of Iran (Illam and Lorestan provinces). Six input variable combinations were considered based on Pearson correlations between candidate model inputs (time of measuring and soil bulk density, moisture content, and sand, clay, and silt percentages) and CI. The dataset was divided into two subgroups at random:70% of the data were used for model building (training dataset) and the remaining 30% were used for model validation (testing dataset). The various models were evaluated using different graphical approaches (bar charts, scatter plots, violin plots, and Taylor diagrams) and quantitative measures (root mean square error (RMSE), mean absolute error (MAE), Nash-Sutcliffe efficiency (NSE), and percent bias (PBIAS)). Time of measuring had the highest correlation with CI in the study area. The best input combinations were different for different algorithms. The results showed that all hybrid algorithms enhanced the CI prediction accuracy compared to the standalone models. The AR-M5P model provided the most accurate CI predictions (RMSE=0.75 cm, MAE=0.59 cm, NSE=0.98), while the SCS model had the lowest performance (RMSE=4.77 cm, MAE=2.64 cm, NSE=0.23). The differences in RMSE between the best model (AR-M5P) and the second-best (WIHW-M5P) and worst (SCS) were 40% and 84%, respectively.  相似文献   

Characterization of Lasiodiplodia species causing leaf blight,stem rot and fruit rot of fig (Ficus carica) in Malaysia     

Abdul Omar Nur-Shakirah  Mohd Safie Khadijah  Yee Jia Kee  Abd Rahim Huda-Shakirah  Abu Bakar Mohd Hafifi  Yakath Ali Nurul-Aliyaa  Bee Lynn Chew  Latiffah Zakaria  Nik Mohd Izham Mohamed Nor  Subramaniam Sreeramanan  Yin-Hui Leong  Masratul Hawa Mohd 《Plant pathology》2022,71(7):1594-1605

Fig (Ficus carica) is an exotic deciduous plant that is grown worldwide. Fungal diseases pose a major threat to fig plants, affecting their fruit quality and production. This study was conducted to characterize the fungal isolates associated with leaf blight, stem rot and fruit rot of F. carica in Malaysia through morphological analysis, DNA sequencing, multigene phylogenetic analysis and pathogenicity tests. From September 2018 to March 2019, 30 blighted leaves and 30 rotted stems and fruits of F. carica were collected from several nurseries in Malaysia. Thirty fungal isolates that belonged to Lasiodiplodia theobromae (27 isolates) and L. brasiliensis (three isolates) were identified based on morphological characteristics, comparison of DNA sequences and phylogenetic analysis of the internal transcribed spacer (ITS), elongation translation factor 1-α (tef1-α), β-tubulin (tub2) and DNA-directed RNA polymerase II subunit (rpb2). Among the 27 isolates of L. theobromae, nine isolates were obtained from leaves, eight isolates from stems and 10 isolates from fruits, whereas the three isolates of L. brasiliensis were obtained from stems (two isolates) and a leaf (one isolate). The results of pathogenicity tests revealed that L. theobromae and L. brasiliensis isolates were responsible for leaf blight and stem rot of F. carica, whereas fruit rot was caused by L. theobromae isolates. The present study highlighted two different species, L. theobromae and L. brasiliensis, as the causal agents of leaf blight and stem rot of F. carica. Additionally, L. theobromae caused fruit rot of F. carica in Malaysia.  相似文献