American Journal of Agricultural Research

  • Design of Twin Screw Feather Extruder and Study of Screw Parameters

    Poultry feathers are rich in amino acids and keratin resources, which is a kind of protein feed raw materials with high nutritional value. A twin-screw extruder was designed to deal with the environmental damage caused by the shortage of rapidly developing protein feed and the large amount of feather waste in China’s livestock breeding industry. The bulking machine can break the disulfide bond and hydrogen bond in feather keratin to form crude protein which can be absorbed by livestock. A kind of high-protein feed feather powder was developed while protecting the environment. The combination mode and rotation direction between two screws are discussed, the relationship between the key basic parameters of the twin screw is derived by combining the motion principle of the twin screw and the relative geometric position. It provides theoretical basis for determining screw parameters and working condition parameters in the following experimental research.

  • Nutritional Potential of Some Invasive Species of Macaronesia for Ruminants

    Macaronesia islands’ invasive plant use in animal feed or composting may bring economic and environmental benefits to the region. Arundo donax, Pennisetum setaceum, Agave americana, and Ricinus communis, present in the three archipelagos (Canary, Azores and Madeira), were characterized chemically and biologically. A. donax and P. setaceum showed elevated crude protein (CP) content, 13.25 and 16.33 DM%, respectively, and extremely high NDF values, 75.87 and 80.83 DM%, with a DM digestibility of 55.02 to 59.77%. A. americana showed a low NDF value (22.78 to 27.94 DM%) and a very low CP value (4.24 to 5.61 DM%). However, its DM digestibility was high (79.89 to 86.33%). R. communis presented the best values for CP (24.62%) and NDF (26.56 DM%), however, due to the presence of toxic substances (ricin), it cannot be easily used in animal feed. The P. setaceum and R. communis were found to be the least gas-producing forage, with A. americana being the major producer. To increase these plants’ value for animal feed, treatment with urea or NaOH to A. donax and P. setaceum, and enrichment with nitrogen to Agave is proposed. Due to its toxic properties, R. communis must be used in composting.

  • Research status and prospects of potato seed-metering device

    Potato has been widely planted, and China’s potato planting area and total output have become the first in the world. As an important part of the whole mechanization technology, potato planting mechanization directly affects the quality and yield of potato. As the core component of potato planter, the performance of seed metering device directly affects the operation quality of planter. In recent years, with the continuous efforts of researchers and manufacturers at home and abroad, the types and research technology of seed metering device are constantly innovating and improving. This paper mainly introduces the key technologies and types of seed metering devices used in the main models in China and abroad, as well as the existing problems and future development direction of different types of seed metering devices.

  • The influence of biofertilizer effect on switchgrass (Panicum virgatum) crop yield under greenhouse and field conditions in Guelph, Ontario, Canada

    Greenhouse and field experiments were conducted to test the effectiveness of biofertilizers on switchgrass (Panicum virgatum) yields compared to inorganic fertilizer and a zero-control. In the greenhouse, Variovorax paradoxus JM63, JumpStart® (Penicillium bilaii), inorganic fertilizer and control treatments resulted in significantly higher per L pot biomass yields compared to the control treatment; 2.74 (±0.24), 2.55 (±0.10), 2.52 (±0.24) and 1.34 (±0.09) g L-1, respectively. As JumpStart® is a commercially available biofertilizer, it was used in the field experiment along with inorganic and control treatments. All three treatments were applied to established (2014) switchgrass plots. Significantly (p

  • Comparative analyses of plantain vivoplants responses to different clam shells and Tithonia diversifolia treatments in terms of growth promotion and induced resistance against Mycosphaerella fijiensis

    The seeds availability and quality are the main constraints for agricultural explosion of plantain productivity in sub-Saharan Africa countries. Plantain vivoplants were generated and submitted to different treatments in the nursery, the plant responses were analysed and compared in other to determine the best treatment influencing the growth promotion and induced resistance to Mycosphaerella fijiensis. Plantain explants and vivoplants were treated with five different treatments: clam shells powder (T1), clam shells and Tithonia diversifolia powder (T2), Tithonia diversifolia flakes (T3), Tithonia diversifolia mulch (T4), Tithonia diversifolia liquid extract (T5). The treatments were applied by their incorporation in the substrate (T1, T2, T3 and T4) or by watering of the whole plant (T5). The germination rate was evaluated and recorded in the greenhouse at the germination and pre-emergence stage, followed by the agromorphological measurements on the vivoplants and their inoculation with Mycosphaerella fijiensis in the shade at the vegetative growth stage. Biochemical analysis was done on the vivoplants leaves tissues. The vivoplants respond positively to all the treatments by a quick germination and emergence, coupled with an important biomarker’s accumulation (total proteins and phenolics). It turns out that the best treatment was T5 (T. diversifolia liquid extract), followed by T4 (T. diversifolia mulch). However, depending on the expected response in the vivoplants, all these treatments have proven to be impactful. Therefore, a combination of Tithonia diversifolia liquid extract (T5) with clams’ shells (T1) could be useful to boost the production at low cost and without chemical inputs of large amount of improved vigorous (clean and less susceptible) planting material, impacting thus the food security and poverty alleviation.

  • Research status and development trend of seed-metering device in China

    As the main tool of soybean mechanization production, the performance of soybean seeder is directly related to the sowing quality and yield of soybean.As the core component of the seeder, the soybean seed-metering device directly affects the seeding accuracy, uniformity, seed emergence rate, etc.This article introduces the research status and future development trend of soybean seed-metering devices in China in recent years, analyzes the characteristics of soybean seed-metering devices in China, and provides a basis for the further development of seed metering devices in China.


    Residue trials of deltamethrin in black pepper (Piper nigrum) were conducted to estimate the maximum residue limit (MRL). Five residue trials were conducted at three commercial growers’ plots in Johor, Perak and Sarawak (Malaysia). The study plots contained 120 mature pepper vines which were selected and treated with deltamethrin using the manufacturer’s recommended rate (0.01 kg a.i./ha). The insecticide was applied with a motorized sprayer on monthly intervals. Green pepper berries samples (500g) were randomly collected from the plots at 1, 3, 5 and/or 7 days after the last spray. Analytical procedure of deltamethrin extraction was validated prior to actual analysis. Satisfactory recoveries ranging from 86.2% to 110.2% were obtained for the fortified pepper berries samples. The limits of detection and limits of quantification for deltamethrin were 0.521 μg kg−1 and 1.63 μg kg−1, respectively. Results showed that deltamethrin residues were at the low level with the residue value ranging between

  • Research status of Rice direct seeding device in China

    Aiming at the problems of rice seedling raising, transplanting and so on, low production efficiency and low mechanization efficiency, we popularize the rice direct seeding technology, through investigating and studying the development status of representative rice direct seeding machine in China, analyze its basic structure and working principle, and put forward the existing problems and development suggestions of rice direct seeding machine. Research shows that rice direct seeding technology has a broad development space in China. It is necessary to further optimize the design of key components such as seed metering devices and improve independent research and development capabilities to improve the versatility and efficiency of the rice direct seeding machine, so that China’s rice direct seeding technology can Rapid development.


    Plantain seedlings availability in sub-Saharan countries are very weak to support a high productivity level required. The plantain cultivation faces problem of the seedling’s unavailability in quantity and quality for intensification of this crop. The amendment of PIF substrate production with natural products could be an alternative to this problem. This study objective is to evaluate the effect of vertical layers of Tithonia diversifolia flakes on the performance of PIF plantain seedlings in terms of vegetative growth and susceptibility to black Sigatoka disease (BSD) in nursery. The vertical layer of T. diversifolia flakes amendment was introduced in the propagator in the presence of the control without amendment in controlled and uncontrolled conditions for shoots, then seedlings generation, followed by the evaluation of the vegetative growth parameters, the inoculation of the leaves with Mycosphaerella fijiensis and the pool of biomarkers evaluation. The treatment increases the germination rate, the number of shoots, the height and the diameter of shoots, the area of leaves as well as the seedlings roots, but also protects the seedlings against BSD up to about 56% compared to the controls. It also enhances the accumulation of proteins, polyphenols content and enzymes such as peroxidase, polyphenoloxidase and glucanase. The dual role of the vertical layer of T. diversifolia flakes in seedling production as a biofertilizer and as a biopesticide was revealed in this research. Taking into account this bad herbs flakes as a tool for sustainable and green agriculture is an open door to poor peasants for their empowerment.

  • Prosopis cineraria (Ghaf): An Unconventional Desert protein rich supplement

    Prosopis cineraria (Ghaf) is not well known as a rich and sustainable source of protein for many people in the world. It emphasis on its broad food and non-food applications, nutritional values and health benefits. This research was carried out to meet the increasing demand of protein, alternative strategies and unconventional sources of protein for human and animal nutrition. This is probably the first research work which provides a comparative study between the protein content of ghaf leaves with different species of fish muscle protein. Fish muscle homogenate was prepared using ice cold distilled water. The muscle homogenate of Euthynnus affinis showed highest protein 137.5 mg/g. The other fishes muscle protein were Carangoides chrysophrys (43.33 mg/g), Lenthrinus lentjan (105 mg/g), Sardinella longiceps (104.17 mg/g), Pomacanthus maculosus (81.67 mg/g), Nemipterus japonicus (111.67 mg/g), Lutjanus ehrenbergi (99.17 mg/g), Gerres oyena (107.5 mg/g), Argyrops spinifer (100.83 mg/g), Terrapin jarboe (82.5 mg/g), Tilapia mossambica (54.72 mg/g). Ghaf tree is a keystone species having multiple beneficial uses from combating desertification and improving soil fertility in arid environments to being an essential food source, as well as a source of fuel, shelter and medicine for both humans and animal species. The Ghaf leaves extracts were tested for protein content analysis. The protein content in Ghaf leaves was found to be 88.61 mg/g. Thus, the research results revealed that Ghaf leaves has almost similar amount of protein as compared to fish muscle protein and can be used as protein supplement for growth and metabolism of body.