Capillary-based subsurface irrigation system for water-saving agriculture

Fresh water deficit will become crucial and the world will face the crisis in the next 10 years when the world population exceeds 8 billion. Agricultural activities which consume more than 70% of the available water are in great threat from competition with industrial and domestic use. However least efforts have been done to reduce water usage and practice water-saving in agriculture compared to the industrial and domestic because of the abundant available of this resource in many arable land. The irrigation management practices however are still advancing with newer technologies with higher efficiency. The aim of this study is to investigate the feasibility of the fibrous-capillary system for water-saving irrigation system. Capillary irrigation has a great potential to save water in agriculture because water is supplied directly into the rooting zone by the gradient of soil water potential caused by plant water uptake. An advancement of the capillary irrigation system is being introduced in this study in which a fibrous material is used as an interface to transport water from reservoir into the rooting zone. Water that flow in this system is managed by capillary action. A nonwoven fibrous sheet or a geo-textile system with high capillarity is used as the interface material. Water can be transported easily within the soil area using the fibrous system by the capillary flow. Infiltration into the soil from the fibrous system is at the soil natural absorption rate, thus creating a uniform wetting pattern by matching the soil capillary absorption properties. This allows the soil to absorb water as needed at a slower and more effective rate. On the other hand, plant uptake water freely from the wetted soil for transpiration. As the potential gradient increases, the water flow continues from the reservoir through the fibrous to replenish the deficit. The continuous water supply will sustain the soil-plant evapotranspiration at very minimum stress. This process is regarded as a plant-based irrigation system, which is being emphasized in this study in a new irrigation system. The control of the fibrous-capillary system is done by manipulating the distance between the interface of the soil-fibrous to the water in the reservoir known as water supply depth. Manipulation of the depth will affect the capillary flow through the fibrous thus changing the irrigation volume rate. As the result the plant evapotranspiration will be affected. An optimal water supply depth will ensure sufficient water supply to the plant for healthy growth while minimizing the evaporation from the soil. Experiments were conducted, by using the fibrous-capillary system apparatus built in a cylindrical and a rectangular container. A small reservoir with an adjustable water level controller was located under the container. A vertical fibrous sheet used to transfer the water was position on the container floor and buried in the soil. The other end of the vertical fibrous was immersed in the reservoir. A closed-climate chamber and a phytotron were used to conduct experiments related to water flow and plant water uptake. The results revealed the dynamics of water flow and soil moisture condition in the fibrous-capillary system which was largely affected by the climatic change and the plant growth stages. Moreover the dynamics were also affected by the change of water supply depth where the advancement of wetting front, soil water content and the cumulative infiltration were almost proportional to the decreased of the depth. This phenomenon was modeled by using a soil-plant-atmosphere-continuum (SPAC) approach and a modified version of the SPAC model was introduced. The time-space variation of water flow and wetting pattern in the fibrous-capillary system was successfully simulated and visualized based on Richard equation using HYDRUS. An adaptive strategy is proposed to control this irrigation system in order to adapt the dynamic need of water by the plant at various growth stages has shown very substantial results in water-saving strategy. This study has contributed to a new cultivation management strategy by water-saving irrigation system in which the system will significantly reduce the input cost and increase the profit. Proper utilization of the system and management assures better plant quality with less water by maintaining near perfect air/water content in the soil. All chemicals that may go through the system directly into the rooting zone shall result in excellence plant health with substantially less fertilizers by eliminating surface exposure which reducing harmful and wasteful run-off. The system offers a great technology for industry to develop a new watersaving irrigation system. The originalities of this study lies on the mechanism to transport water directly into the rooting zone by using the fibrous-capillary system and the measuring-control method for detecting plant water demand and supplying the accurate amount based on the detected demand

モウカン ゲンショウ オ リヨウシタ セッスイ チカ カンガイ システム

博士（農学）東京農工大

Agricultural rout planning with variable rate pesticide application in a greenhouse environment

The use of robotics in executing agricultural tasks has significantly improved productivity over the years as a result of automation in performing such activities as spray, harvesting, planting etc. In order to optimize both crop yield and quality while minimizing costs, there will be need for the application of navigation strategies. These will provide optimal as well as autonomous navigation capability which is built entirely upon field coverage plan thereby making robot navigation approach a paramount scheme. In this paper, the autonomy of an agricultural mobile robot is enhanced in a structured environment (greenhouse farm) to locate an optimum route such that the robot performs a selective and variable spray of pesticides to the plants. To realize this, a robust vehicle routing problem (VRP) scheme is designed to navigate the robot autonomously while making intelligent decisions to fulfil the pesticide demands at each node (infected plants). The improved non-dominated sorting genetic algorithm (INSGA-III) is adopted to solve this fully integer problem based on three (3) test cases carried out with 8, 32 and 56 infected plants respectively for validation. The results obtained show a trade-off solution as the Optimal INSGA-III is significantly lower than NSGA-III in terms of solution quality. On the other hand, a significant reduction in run times of between 66% and 76% and 76–93% was obtained for all test case scenarios for population sizes of 100 and 1500 respectively

Gancidin W, a potential low-toxicity antimalarial agent isolated from an endophytic Streptomyces SUK10

Endophytic Streptomyces strains are potential sources for novel bioactive molecules. In this study, the diketopiperazine gancidin W (GW) was isolated sfrom the endophytic actinobacterial genus Streptomyces, SUK10, obtained from the bark of Shorea ovalis tree, and it was tested in vivo against Plasmodium berghei PZZ1/100. GW exhibited an inhibition rate of nearly 80% at 6.25 and 3.125 µg kg-1 body weight on day four using the 4-day suppression test method on male ICR strain mice. Comparing GW at both concentrations with quinine hydrochloride and normal saline as positive and negative controls, respectively, 50% of the mice treated with 3.125 µg kg-1 body weight managed to survive for more than 11 months after infection, which almost reached the life span of normal mice. Biochemical tests of selected enzymes and proteins in blood samples of mice treated with GW were also within normal levels; in addition, no abnormalities or injuries were found on internal vital organs. These findings indicated that this isolated bioactive compound from Streptomyces SUK10 exhibits very low toxicity and is a good candidate for potential use as an antimalarial agent in an animal model

Advancement of a smart fibrous capillary irrigation management system with an Internet of Things integration

This paper presents the development work for integrating an Internet of Things (IoT) with a fibrous capillary irrigation system based on the climatic demand estimated by the weather condition. The monitoring and control using an IoT system is critical for such application that is targeted for precision irrigation. The fibrous capillary irrigation system is managed by manipulating a water supply depth using the potential evapotranspiration (ETo). A soil mositure sensor was used to monitor the progress of the root water uptake and input the fuzzy logic system, to determine the water requirements for the crop medium. Experiment was conducted by using a Choy sum plant as the test crop grown in a greenhouse. The monitoring of the demand and management of the watering system was successful. The ETo data was able to approximate the crop water requirement in near real time

Modelling and control of DWR 1.0 – a two wheeled mobile robot

This paper presents modelling and control of DWR 1.0, a two wheeled mobile robot. This balancing robot is one of the applications of an inverted pendulum on a two wheel. A relatively recent offshoot of the classical inverted pendulum is the wheel inverted pendulum, popularized in contemporary culture by the Segway Personal Transporter. However, the mathematical model for a wheel inverted pendulum do not account for the full complexity of the construction of the platform. The mathematical model obtained in this work with the measured parameters is simulated using Matlab and PID control parameters are determined. Finally, PID control algorithm is implemented on the two-wheeled mobile robot to test the accuracy of the model

In-vivo antimalarial activity of the endophytic actinobacterium, Streptomyces SUK 10

Endophytic bacteria, such as Streptomyces, have the potential to act as a source for novel bioactive molecules with medicinal properties. The present study was aimed at assessing the antimalarial activity of crude extract isolated from various strains of actinobacteria living endophytically in some Malaysian medicinal plants. Using the four day suppression test method on male ICR strain mice, compounds produced from three strains of Streptomyces (SUK8, SUK10, and SUK27) were tested in vivo against Plasmodium berghei PZZ1/100 in an antimalarial screen using crude extracts at four different concentrations. One of these extracts, isolated from Streptomyces SUK10 obtained from the bark of Shorea ovalis tree, showed inhibition of the test organism and was further tested against P. berghei-infected mice for antimalarial activity at different concentrations. There was a positive relationship between the survival of the infected mouse group treated with 50 μg/kg body weight (bw) of ethyl acetate-SUK10 crude extract and the ability to inhibit the parasites growth. The parasite inhibition percentage for this group showed that 50% of the mice survived for more than 90 days after infection with the parasite. The nucleotide sequence and phylogenetic tree suggested that Streptomyces SUK10 may constitute a new species within the Streptomyces genus. As part of the drug discovery process, these promising finding may contribute to the medicinal and pharmaceutical field for malarial treatment

Endophytic Streptomyces SUK10: its molecular characteristic and bioactivity against malaria parasite

It has been known that Streptomyces is the mains source for antibiotics. The present study found that the crude extract obtained from Streptomyces SUK10 living endophytically in Shorea ovalis tree has antimalarial activity against Plasmodium berghei strain PZZ1/100. Using validated surface sterilization and isolation method, Streptomyces SUK10 was isolated from the bark of Shorea ovalis by and cultured on the isolation agar. With spiral spore chain, microscopically, this strain has substrate mycelium in brownish yellow and aerial mycelium in whitish grey, other than yellow dissolved pigment. As showed in early molecular tests, the 23S rRNA sequence of Streptomyces SUK10 was 96% identical to Streptomyces hygroscopicus, the outstanding producer of Hygromycin B antibiotic. In early phase of antimalarial screening, the secondary metabolites from three different strains of endophytic Streptomyces isolated from three different trees were in-vivo tested on the mice ICR strain against P. berghei strain PZZ1/100. These were done by implementing the four days (4D) suppression test using their own ethyl acetate-crude extract at four different concentrations: 50, 100, 200 and 400 µg/kg body weight (bw). Upon obtaining significant results (p ≤ 0.05), ethyl acetate-SUK10 crude extract were screened for fully anti-malarial activity at five different narrower concentration range 5, 10, 50, 100 and 200 µg/kg bw. There was a positive relationship between the survival of the infected mice group treated with 50 µg/kg body weight of ethyl acetate-SUK10 crude extract and its ability to inhibit the parasites growth. Considering quinine hydrochloride at 10 mg/kg bw and 0.9% normal saline as positive and negative control respectively, the parasite inhibition percentage for this group at certain concentration showed more than 70% and 50% of this mice members (n=3) were also able to survive more than 90 days after the infection with the parasite. Nevertheless, Indole-3-lactic acid (C11H11NO3) was isolated from the anti-trypanosomal active fraction while Gancidin W or Maculosin 6 (L-leucyl-L-prolyl lactam, C11H18N2O2) was the major compound found from SUK 10 crude extract. Gancidin W has been previously reported to be anti-parasitic which we are still yet to be tested for anti-malarial activity and its cytotoxicity. These promising findings contribute to the medicinal and pharmaceutical field for future antimalarial treatment

Gancidin W, a potential low toxicity antimalarial agent isolated from an Endophytic Streptomyces SUK10

As it resisted against nearly all current drugs, malaria was reported remained as the most threatening human parasitic disease. In line with this, endophytic Streptomyces are potential sources for novel bioactive molecules. In this study, prolyl-leucyl-diketopiperazine (C11H18N2O2) or Gancidin W (GW) was successfully isolated from Streptomyces SUK10 that inhabited in the bark of Shorea ovalis. Using four days suppressive test (4DST), this compound was in-vivo tested against Plasmodium berghei NK65. At 6.25 and 3.125 µg kg-1 body weight (bw), there was a very significant relationship of the ability to inhibit the growth of P. berghei NK65 when GW exhibited an inhibition rate of nearly 80% on male ICR strain mice. Comparing GW with dH2O diluted quinine hydrochloride and 0.9% normal saline as positive and negative controls respectively, 50% of the mice group treated with 3.125 µg kg-1 bw was managed to survive more than eight months post-infection exposure where this survival ranged was exceeded half of the normal mice’s life span period. As in-vivo toxicity assessment towards selected vital organs and blood enzymes were also investigated, the ALT and AST enzymes level was slightly higher but there was no abnormalities and injuries were found on the tested organs of the mice group treated with GW at this concentration. These findings indicated that GW isolated from Streptomyces SUK10 exhibited very low toxicity and is a good candidate as a potential antimalarial agent

Design of an autonomous two-wheeled balancing robot for educational purpose

The scope of the symposium will be related to key technologies in Japan and Malaysia. The areas of focus will be related to key and future technologies as well as highly demanding manufacturing technologies in the industrial fields of Electrical & electronics, Automotive, Energy and environment, Innovative IT, Basic metals & Materials, Machinery & equipments, Chemicals, Bio-Technology, Plastics, Oil and petroleum, Life Sciences, Wood, Food, Rubber, Agriculture engineering