Allelopathic potential of the leaf and seed of Pueraria javanica Benth. on the germination and growth of three selected weed species

Pueraria javanica Benth. is one of the most common leguminous cover crop used in oil palm plantations of Malaysia. A study was conducted to determine the allelopathic potential of this plant, using the aqueous extract, sandwich and dish-pack methods, with the seed and leaf (of P. javanica) on three bioassay weed species namely, Eleusine indica, Cyperus iria and Chromolaena odorata. The aqueous extract experiment was conducted using 0 (control), 16.7, 33.3 and 66.7 g/L of the aqueous leaf and seed extracts while the sandwich method was carried out using 10 and 50 mg of each of the donour plant parts. Meanwhile, the dish-pack method was done using four different distances (41, 58, 82 and 92 mm) away from the donour plant. All experiments were replicated five times using the complete randomized design (CRD). The leaf extract exhibited 100% reduction on the fresh weight of E. indica and C. odorata while the seed extract exhibited 100% reduction on all parameters for E. indica and on the fresh weight of C. iria at 66.7 g/L concentration. The seed and leaf at 10 and 50 mg significantly reduced the radicle length of all the bioassay species. The dish-pack experiment also showed a reduction effect on the germination percentage and seedling growth parameters of all the bioassay species. However, the reduction effect was not totally in accordance to the distance from the donor species. More studies need to be conducted to determine the type of reduction mechanism involved in the allelopathic activity especially with respect to molecular and biochemical aspects

Effects of Fish Waste Extract on the Growth, Yield and Quality of Cucumis sativus L.

This study was conducted to evaluate the potential effects of fish waste extract on the growth, yield and quality of cucumber which is a popular cucurbitaceae fruit vegetable. Different treatments were arranged according with CRD layouts with five replicates for each treatment.  All the six (6) treatments viz; control, NPK, 10 ml, 20 ml, 40 ml and 50 ml of fish waste extract were applied to the potting media. The results showed that the application of 20 ml of fish waste extract increased the vine length, number of leaf, chlorophyll content (SPAD), stomatal conductance and leaf TSS content of cucumber compared to other treatments and control. Treatment with 50 mL of fish waste extract produced the highest leaf area. The chlorophyll concentration, carotene content, chlorophyll fluorescence and photosynthetic yield also positively affected with fish waste extracts. It was also found that number of flower, number of fruit, and weight of individual fruit of cucumber also significantly increased by fish waste extracts.  It can be concluded that 20 ml fish waste extract was the best treatment for improving the growth, yield and quality of cucumber. Foliar application of fish waste effluent on Cucurbitaceae vegetables is merit to further study

Environmental Effects on Germination and Seedling Emergence of Weedy Rice

The objective of this study is to determine the germination and growth of weedy rice seedlings that were grown under four different environmental conditions simulated in either growth chamber or room conditions. Photoperiod (24 h light, 24 h dark, 12 h light-dark), drought (0, 5, 10, 20 %) and temperature (25, 30, 35, 40 °C) effects were tested in growth chamber while the flooding depth (0, 2.5, 5, 10 cm) effects was tested in room condition. Germination percentage was not significantly affected (p > 0.05) by either of the environmental factors except for flooding depth at 10 cm. Temperature treatment specifically at 30 °C showed a pronounced effect on hypocotyl length, radicle length and root-shoot ratio compared to other temperature range. Highest hypocotyl length and root-shoot ratio were recorded in 10 % drought treatment and longest radicle length obtained in control treatment. Meanwhile, a continuous dark condition in photoperiod treatment showed the highest hypocotyl length in comparison to 24 hours of light and alternate 12 hours of light and dark. Highest radicle length and root-shoot ratio were obtained in 24 hours of light and 12 hours alternate light and dark respectively. Growth of weedy rice exhibited a declining trend in increasing flooding depth. The result of this study suggests that germination was retarded by deep flooding. Temperature and flooding depth affects the vegetative growth of weedy rice the most and sustained growth was observed at higher temperature regime. The information gained from this study may be useful in assessing the growth performance of weedy rice in relation to cultivated rice, and further helps in developing effective Malaysian weedy rice control strategies

Evaluation of Allelopathic Potential of Pluchea indica on Brassica chinensis and Zea mays

Weeds have become one of the leading causes of crop production losses, including the cost of weed management, weed crop competition, and weed intervention with crop management practices. Moreover, herbicide use in agricultural systems is currently being debated due to the potential adverse effects on the environment and human health. The utilization of the allelopathic phenomenon is widely considered an alternative weed management strategy. However, allelopathic study of Pluchea indica plant was limited. P. indica is a flowering plant under family Asteraceae, locally known as Beluntas. Thus, this study was conducted to determine the allelopathic effects of the aqueous leaf extract of P. indica on the seedling growth of tested plant species and to investigate the effect of P. indica leaf debris on the growth of tested plant species. In this study, the allelopathic potential of P. indica leaves were investigated through petri dish bioassay and soil bioassay method. The two tested plant species were chosen for the bioassay: monocotyledonous; maize (Zea mays) and dicotyledonous; mustard (Brassica chinensis). These tested plant species were chosen for the experiment due to their known quick seedling growth behaviours and commonly used in allelopathic studies. The result showed that as the concentration of aqueous leaf extract increased, the inhibition percentage of the radicle length of B. chinensis and Z. mays were increased. However, stimulatory effect was observed on the radicle length of B. chinensis and Z. mays when 1.3%and 2.5% w/w  P. indica leaf debris were applied. Thus, aqueous leaf extract and leaf debris of P. indica have potential allelopathic effects on the growth of B. chinensis and Z. mays. Further studies need to be conducted on other bioassay species especially weed species, to elucidate the allelopathic potential of P. indica in weed control

Evaluation for Allelopathic Activity of Selected Tree Species Grown in BRIS Soil

This study was carried out to evaluate the allelopathic activity of selected tree species grown in BRIS soil. The mature leaves from ten different tree species were collected as the material of donor plants. They were evaluated for the allelopathic activity of the leaf litter leachate and leaf volatilization by using Sandwich and Dish pack methods respectively, while Lactuca sativa (lettuce) was used as the receiver plant. Different amounts of leaf litter leachate were tested on the lettuce seedling growth for Sandwich method whilst, for Dish pack method the allelopathic activity was tested on different distances of the receiver plant from the donor plants. The results for Sandwich method showed that the tree species that gave the highest radical inhibition was Mangifera indica (mango) (60.05%) while the highest hypocotyl inhibition was Peltophorum pterocarpum (Yellow flame tree) (12.58%). Meanwhile, Manihot esculenta (cassava) showed the highest inhibition of radicle and hypocotyl by 86.50% and 76.63%, respectively, compared to control using Dish pack method. Based on this study, the evaluation for allelopathic activity of selected tree species grown in BRIS soil showed that there is significant presence of the allelochemicals in the tested tree species. The development of natural herbicides can be achieved with further studies to determine the effectiveness of allelochemicals in the tree species

Allelopathy activity under laboratory, greenhouse and field conditions: A review

Weeds are one of the significant problems that impact agriculture production. Farmers have been using synthetic herbicides to control weed infestations in the field. However, the excessive usage of herbicides has led to various environmental concerns, including the emergence of herbicide resistant weeds. Allelopathy is an environment-friendly alternative that can control weeds. Here, we performed a systematic literature review to assess the potential and effects of allelopathy under laboratory, greenhouse and field conditions. Articles were collected by searching the SCOPUS database and guided by PRISMA. Of 371 studies identified, forty-three articles used allelopathy to control weeds under greenhouse and field conditions, with Poaceae being the prominent family studied as donor plants. Six articles reported up to 80% weed growth suppression when spraying allelopathy extract under greenhouse conditions, while mulch and soil incorporated with donor plants contributed over 50% suppression under field conditions. The findings revealed that 20 studies had conducted metabolite identification to determine the allelochemicals with phytotoxic activity against target plants. However, the mechanism of allelopathy was not thoroughly investigated. In conclusion, we found an increasing trend of allelopathy experiments conducted under greenhouse and field conditions. Furthermore, field trials should be included to validate laboratory data and to provide insight into allelochemical action and its relationship with the environment

Growth Performance of Oil Palm Seedlings on Different Types of Organic Fertilizer

Fertilizer and soil nutrient management is important to sustain the productivity of nursery systems for oil palm seedling. Inorganic fertilizer usually applies to the oil palm seedling in nursery. The problem of the inorganic fertilizer nowadays is the price is quite expensive and can cause pollution if not manage well. So, by changes the inorganic to organic fertilizer, farmers can reduce their cost, and can gets many benefits through the usage of organic fertilizer. This study investigated the effects of organic fertilizer on growth performance and development of oil palm seedling. 3-month-old Tenera oil palm seedling was treated with an organic fertilizer (10 g of goat manure, 10 gram of fish waste and 10 gram of coffee waste). Control treatments were left untreated. Growth of seedling, plant morphology, plant physiology and soil pH were measured to compare among the treatments. Application of organic fertilizer significantly increased number of fronds about 28% to 46% compare from the control treatment, 28% to 41% increment in plant girth for treatment that treat with organic fertilizer, and significantly increase chlorophyll content of oil palm seedling leaves more than 11% for organic fertilizer application but not significantly increase the plant height and relative growth control (RGR). Several treatments on different organic fertilizer, like soil pH and relative water content (RWC), not significantly different from control but application of organic fertilizer help to increase the soil pH and help to increase the percentage of RWC in plant. These finding indicates that application of different organic fertilizer help to improve several morphology characteristics like number of fronds, and plant girth. It also can help to increase the chlorophyll content in leaves and help to improved soil pH. In future, application of organic fertilizer can be fully utilized for growth and development of oil palm seedling in nursery where it can help to reduce the usage inorganic fertilizer and help to reduce the cost of the nursery

Allelopathic Assesments of Ficus deltoidea Jack Varieties and Ficus microcarpa L.f. (Moraceae) on Lactuca sativa L. Seed

This study described allelopathic potential of two medicinal plant species, Ficus deltoidea varieties in comparison with Ficus microcarpa, by using testing the leaf-litter leachate through sandwich method and the leaf extracts through methanolic extraction method, with three replications for each donor species by using the complete randomized design (CRD). The sandwich method was carried out by using 5 mg, 10 mg and 50 mg dry weight of the donor plants leaf. Among the eight donor plant tested, results showed that var. kunstleri had the highest growth inhibition on lettuce radicle elongation (57.51%) as compared to control, followed by var. trengganuensis (45.50%) and Ficus microcarpa (39.95%), respectively. Meanwhile, the methanolic extraction was done by using different concentrations of leaf extract (0.1 ppm, 1 ppm, 10 ppm and 100 ppm). In the methanolic extraction bioassay, the var. kunstleri and var. trengganuensis that have the highest inhibition on lettuce growth were further selected to be tested by using this method and was observed to have a high inhibition on lettuce radicle elongation at 66.63% and 64.95%, respectively, as the concentration increases. Further studies can be conducted on the identification and isolation of allelochemical by using this finding as the background information towards the development of bioactive compound as natural botanical herbicide for weed management

MyPlantDIY (Malaysian plant diagnose it yourself) app

The databases of plant disease in Malaysia are already being published in the printed (academic book) and digital form (internet blog). Hence, MyPlantDIY app is innovated by converting these database into easy, fast, up to date and user friendly form. MyPlantDIY app provides the images, the description and the suggested treatments for the particular disease. Besides, MyPlantDIY consists interactive module that can be used as discussion platform and data collection. Thus, MyPlantDIY app provides real pictures of local plant disease and the users can real time compare and diagnose their plant problem rapidly

The effects of hydrogen peroxide on plant growth, mineral accumulation, as well as biological and chemical properties of Ficus deltoidea

Hydrogen peroxide (H2O2) is defined as a reactive oxygen species (ROS), able to cause damage to a variety of cellular structures. On the other hand, recent work has demonstrated that H2O2 can also act as a potent signaling molecule that mediates various physiological and biochemical processes in plants. This study was carried out to investigate the effects of H2O2 on the growth, mineral nutrient accumulation, as well as the biologic and chemical properties of Ficus deltoidea var. deltoidea. F. deltoidea plants were spray-treated with 0- (control), 8-, 16-, 30- and 60-mM H2O2 under field conditions. Plant height, leaf area, chlorophyll content, net photosynthetic rate, stomatal conductance and quantum yield of the F. deltoidea plants significantly increased after treatment with 16 and 30-mM H2O2. The results indicate that 60-mM H2O2 increased the accumulation of arsenic, iron and sodium content in the leaves of F. deltoidea. On the other hand, 8-mM H2O2 significantly enhanced the accumulation of arsenic, iron, calcium and potassium content in the syconium of F. deltoidea plants. In addition, H2O2 treatment did not produce any significant effects on antimony and magnesium accumulation in the leaves or the syconium of F. deltoidea plants. The results show that the F. deltoidea plant has strong antidiabetic properties and its α-glucosidase activity increased in treated plants compared to standard acarbose. Hydrogen peroxide, particularly in concentrations of 16 and 30 mM, increased the antioxidant activity, total phenolic and flavonoid content and the vitexin and isovitexin content. There was a positive correlation between antioxidant activity with total phenol and total flavonoid content in H2O2-treated plants. The quantitative analysis by HPTLC indicates that the amount of vitexin and isovitexin increased with the higher concentrations of H2O2. From this study, it can be concluded that spraying 16 and 30-mM H2O2 once a week enhances growth, mineral accumulation and stimulates bioactive compounds of the F. deltoidea plants