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1.
In tropical climate, huge amount of fertilizer need to be used for the cultivation of kenaf (Hibiscus cannabinus L.) in Beach Ridges Interspersed with Swales (BRIS) soil, however this approach is not cost effective and environmental friendly. Therefore, the optimizing of fertilizer rate for BRIS soils and selection of suitable soil amendments are crucial to get a higher yield. In this study, the effects of different combinations of urea, chicken manure and biochar on soil properties, growth performance and physiological characteristics of kenaf cultivated on the BRIS soil were investigated. Eight treatments were conducted namely: control (T1), biochar (T2), chicken manure (T3), urea (T4), chicken manure + urea (T5), biochar + chicken manure (T6), urea + biochar (T7) and biochar + chicken manure + urea (T8). The biomass and physiological characteristics of kenaf were recorded every month, while the soil was analyzed following a standard laboratory procedure. The application of organic and inorganic fertilizer (urea) significantly increased the nutrient content of the soil compared to the T1, whereas T3 showed the highest pH, cation exchange capacity, and exchangeable bases (Na, Mg, Ca). However, the mixing of biochar with organic and inorganic fertilizers showed the highest plant height, diameter of stem and number of leaves as well as dry biomass compared to other treatments. Furthermore, the application of nitrogen fertilizer significantly increased the photosynthesis rate and stomatal conductivity. The results suggest that the mixing of biochar with organic and inorganic fertilizers represents an effective approach for the cultivation of kenaf in tropical climate.  相似文献   
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Toxoplasma gondii consists of three genotypes, namely genotype I, II and III. Based on its virulence, T. gondii can be divided into virulent and avirulent strains. This study intends to evaluate an alternative method for predicting T. gondii virulence using hierarchical cluster analysis based on complete coding sequences (CDS) of sag1, gra7 and rop18 genes. Dendrogram was constructed using UPGMA with a Kimura 80 nucleotide distance measurement. The results showed that the prediction errors of T. gondii virulence using sag1, gra7 and rop18 were 7.41%, 6.89% and 9.1%, respectively. Analysis based on CDS of gra7 and rop18 was able to differentiate avirulent strains into genotypes II and III, whereas sag1 failed to differentiate.  相似文献   
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Genetic Resources and Crop Evolution - Mangosteen (Garcinia mangostana var. mangostana) is an obligate apomictic species which does not require a fertilization process to produce seeds. The absence...  相似文献   
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Journal of Pest Science - In Peninsular Malaysia, barn owls (Tyto javanica javanica) have been utilized as biological control of rats since the 1960s. In this study, the impact of introduced barn...  相似文献   
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Various methods and criteria have been proposed and utilized for the evaluation of irrigation systems performance, which can be used for comparison of design conditions and irrigation systems performance. Surface irrigation systems should be paid more attention among all other irrigation systems due to their operation simplicity and high losses. In the present study, while describing main relationships of irrigation evaluation criteria of application efficiency, water requirement efficiency, Deep Percolation Ratio and Tail Water Ratio, a method based on SD will be introduced. Modeling of this approach has been done using VENSIM-DSS software. Model has been tested in a case study that included the modeling of a furrow in four irrigation status: current situation, full irrigation, deficit irrigation and finally deficit irrigation with optimized irrigation cutoff time and inflow into furrow. The results reveal the high capabilities of SD approach in modeling water resources and irrigation systems. Its user friendly and ability in transferring data to the data bank can introduce this approach and software as an applicable decision support system.  相似文献   
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The objectives of this study were to assess how functional properties of proteins in whole meal wheat (Triticum aestivum L.) flour vary across different growth environments. Grain from three commercial Australian Hard milling wheat cultivars was analyzed from four growth locations in 2008 and from two of the corresponding cultivars and locations in 2009. The protein content of the grain, soluble and insoluble extractable protein fractions, swelling index of glutenin (SIG), glutenin‐to‐gliadin ratio (Glu:Gli), percent unextractable polymeric protein (%UPP), and dough properties including force at maximum resistance (Rmax) and extensibility were measured. Based on analysis of variance of aggregated data for the cultivars, growth locations, and seasons, growth environment factors made significant contributions to variability in the total grain protein, Glu:Gli ratio, %UPP, SIG, Rmax, and extensibility of the wheat flour. Variability of protein content of the soluble and insoluble extractable protein fractions was mostly owing to genotype.  相似文献   
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This research work reports new electrically conductive paper made of pineapple leaf fiber and polyaniline (PALF/PANI). The conductive paper shows remarkable preservation of mechanical properties while achieving its conductive state. Also it was found that, the amount of PANI needed to achieve the conductivity transformation is as low as 5 wt.%.  相似文献   
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Yemen is one of the world's least developed countries and experiences problems of scarcity of natural agricultural resources as well as soil erosion and degradation. Agroforestry systems (AFS) are being promoted as a more appropriate land use system than monocropping systems (MCS) worldwide. Unfortunately, long-term studies on agroforestry and other land use systems (LUS) do not exist in Yemen. Agroforestry in the Rima'a region has started to deteriorate and many farmers turned to (MCS). This study was conducted in the Rima'a Valley, near Alsharq town, Dhamar, Yemen. The study evaluates the soil nutrients, organic matter (OM), and other soil properties such as pH, bulk density, and porosity under AFS and compares it with soil under MCS. Standard procedures for soil sampling and analyzing were used to collect and analyze 36 composite samples from Site 1 and 36 composite samples from Site 2 from six cropping systems (treatments). The results showed that there were significant variations in relation to LUS. Agroforestry practices—mixed trees with coffee (S1), and Cordia africana L. with coffee (S2) have higher nitrogen concentration (0.17–0.26%) as compared to the Ziziphus spina-christi L. with maize (S3) and the monocropping maize (S5), (<0.16% in both Sites 1 and 2). Similar results were seen on the effect of the different LUS on the soil P, K, and OM contents at the two sites (p < .01). While soil N, P, and soil K were higher under agroforestry systems S1, and S2 in both sites, it was the lowest in S5 in both sites. It can be concluded that agroforestry has more favorable effects on soil fertility and other soil properties. The government should establish programs and campaigns to disseminate AFS technology and promote the importance of agroforestry in soil conservation.  相似文献   
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