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Trichoderma longibrachiatum rarely reported can cause disease in plants. The present study investigates the pathogenicity of T. longibrachiatum isolate UPMT14 on the red leaf lettuce (Lactuca sativa L.) plants grown in sterile soil under a controlled growth room environment. The fungal isolate was initially characterized morphologically as Trichoderma sp. and was then further characterized by (ITS) region sequencing and BLAST comparison identified as T. longibrachiatum. To observe the response of Trichoderma isolate UPMT14 when imposed on lettuce plants. The injection was made and repeated five times, and then the lettuce growth followed for 36 days. On day 36, the present study found that the red leaf lettuce plants expressed foliar symptoms that began as chlorotic, reduced plant height, reduced leaf length and diameter, wilt, and dried up before it collapsed at day 45 compared to untreated control lettuce plants. Microscopic observation on lettuce roots showed that the Trichoderma spores invading the root system by mass sporulation and spatial competition possibly impaired plant water uptake and eventually caused plant wilting. Therefore, this study indicates that T. longibrachiatum is among the causal agents of wilt disease in the lettuce plant.

Many types of soil bacteria through antagonistic activity, thrive in the rhizosphere of plants or surround the tissues of plants and encourage plant development and reduce the nematode population. Bacteria as such are commonly known as Plant Growth-Promoting Rhizobacteria (PGPR). The purpose of this research was to determine Bacillus spp. inoculations impact on tomato seedling development with varying rates of chemical nitrogen-fertilizer. To minimize the recommended quantity of N fertilizer for tomato seedling development, a small pot experiment with selected PGPB was undertaken with varying amount of N fertilizer. Plant growth-promoting bacteria (PGPB) labeled as UPMB10 and UPMRB9 (identified as Bacillus subtilis and Bacillus tequilensis, respectively) were utilized as microbial inoculants because they showed a significant improvement in seedling growth and N concentration in tomato plant tissues in a pot culture investigation. These microbial inoculants significantly improved the development of the plants, stem length, root length, leaves number, dry weight of shoots (stem, leaves), dry weight of roots, SPAD value, N concentration in tissues, and soil bacterial population. Bacteria-treated seedlings with 50% N fertilizer significantly increased stem length (69.07%), root length (78.51%), leaves number (68.58%), shoots (92.45%, 90.39%, stem and leaves, respectively), roots (73.33%), SPAD value (50.31%), and N concentration in plant tissues (63.79%) as compared to the uninoculated control. The findings also showed that inoculation of the Bacillus spp. tomato seedlings could save up to 50 percent of the recommended rate of chemical N fertilizer without affecting tomato seedling growth. The findings of this study suggest that the amount of nitrogen fertilizer given during tomato seedling development can be reduced by half, resulting in increased soil health and reduced environmental pollution.

The bunch moth, Tirathaba mundella is one of the leading pests in oil palm estates established on peatland. Severely infested male inflorescences usually would fail reaching anthesis. Reduction in the number of inflorescences at anthesis stage would suggest less food source and breeding ground for oil palm pollinating weevils, Elaeidobius kamerunicus, thus, affecting the fruiting percentage of oil palm and its yield. Despite to be less detrimental to the environment, biopesticide usages in the field is losing favour due to its slower rate of kill compared with conventional chemical pesticides, shorter persistence in the environment and susceptibility to unfavourable environmental conditions. The use of high host specificity chemical pesticides, such as chlorantraniliprole and chromafenozide are gaining popularity in pest management regimes. In this study, the optimum dose for chlorantraniliprole and chromafenozide in controlling T. mundella was assessed to provide valuable information for sustainable oil palm pest management. Several dosages of pesticide were evaluated for their effectiveness against T. mundella in a 7-year-old oil palm estate for six months. Based on the results obtained, application of 30 g or 40 g active ingredient (a.i.) per ha chlorantraniliprole were recommended to provide the longest protection period. To make plan for an effective pest management that could reduce material and labour cost per ha as well as the risks in developing pesticide resistance among pest, 30 g a.i per ha of chlorantraniliprole is recommended to be rotated with 25 g a.i. per ha chromafenozide for a total of four rounds in a year.

Oil palm bunch moth, Tirathaba mundella Walker is a notorious bunch feeding pest typically among oil palm aged 3-7 years old planted on peat. In order to manage the pest, an economic injury level (EIL) for the pest needs to be determined which could assist in decision-making if a control tactic is justified. In order to determine the EIL, the percentage of fertile oil palm fruitlets and oil to bunch content were determined for fruit bunches with different pest infestation severity. The severity was characterised based on the mean larvae present in fruit bunches and male inflorescences. The study found that the mean larvae count was positively correlated with the economic losses and number of parthenocarpic fruitlets. The overall oil extraction rate (OER) of moderate and severely infested fruit bunches was significantly reduced as compared to clean fruit bunches. Based on average crude palm oil (CPO) market price and production per hectare, an EIL for T. mundella was able to be estimated. This study suggested the EIL at 10% of oil palms per hectare moderately or severely infested. The finding of this study would benefit future pest management practice in oil palm plantation established on peatland.

Tirathaba mundella Walker has emerged as one of the most prominent bunch feeding pests in Sarawak peat oil palm estates. Insecticides application is inevitable to prevent economic loss. However, to protect insect pollinators which cohabitat with the pest and reduce the risk of resistance development among the pest to insecticides, rotation treatments with more than one pollinator-friendly insecticides is recommended. This paper examines the effectiveness of rotating several pollinator-friendly insecticides in controlling the pest. To assess the effectiveness of different rotation combination, a field study on a seven-year-old peat estate was carried out using several insecticides combinations and application intervals, then the level of infestation post-treatment was assessed. Significantly, the results showed that only four single rounds of insecticides application in a year would yield relatively better control than nine rounds of Bacillus thuringiensis applications. Overall, there was no significant difference in clean bunches percentages obtained between five rounds of treatment compared to only four rounds per year. The result strengthens our confidence that the optimum and most cost-effective approach for one-year protection against T. mundella was two rounds of 30.0 g active ingredient of chlorantraniliprole per ha rotated with two rounds of 25.0 g active ingredient of chromafenozide. The material cost was calculated as RM 351.20 per ha per year. The findings of this study would benefit future pest management practice in oil palm plantation established on peatland.

Introduction of new Aspergillus niger strains that are more productive than those currently in use is one of the important steps in promoting more effective commercial citric acid production. The present study was conducted to isolate and characterise indigenous A. niger from selected soil and organic wastes such as soil with buried bamboo, soil with bamboo on the surface, soil under cattle grazing, mango orchard soil, rotting plum fruit and rotting bread. Morphological identification of A. niger was based on the length and width of the conidiophores, vesicles, phialides, and spores. Citric acid-producing Aspergillus isolates were screened based on the citric acid production index. The present study found that the highest fungal spore counts (3.35±0.15 x 107 spores/g sample) were obtained from soil under cattle grazing, as were the highest A. niger counts (7.25±0.05 x 106 spores/g sample). The lowest total fungal counts came from rotting plum fruit (4.70±0.10 x 105 spores/g sample). A total of 14 isolates were collected, with five (NSA03, NSA06, NSA09, NSA12, and NSA14) showing morphological similarities with the reference isolate, A. niger Tiegh. All isolates were able to produce citric acid, but with varying efficiencies according to their citric acid production indices. The soil under cattle grazing area found to be the best site for sampling and isolation for citric acid-producing A. niger by using Czapek-Dox as a medium of isolation.

The objectives of this study were to use pineapple residue ash to (i) reduce ammonium and nitrate leaching and (ii) improve essential nutrient availability on a tropical peat soil under pineapple cultivation. Laboratory leaching experiments were carried out to determine the effectiveness of pineapple residue ash in controlling nitrogen loss from a tropical peat soil. Ion exchange resin method was used to determine nitrogen availability. Treatments evaluated were (i) different amounts of pineapple residue ash (25, 50, 70, and 100%) + NPK fertilizer, (ii) NPK fertilizer, and (iii) peat soil alone. Peat soils with pineapple residue ash reduced ammonium and nitrate losses because of adsorption of ammonium and nitrate by hydroxyl and C–O radicals of the pineapple residue ash. There was an improvement in ammonium and nitrate availability because the pineapple residue ash was able to increase the peat soil pH and this facilitated organic nitrogen mineralization and nitrification. The pineapple residue ash also improved nitrogen uptake, pineapple fresh fruit yield, and fruit quality. Ammonium and nitrate varied with soil depth because of high preferential flow of the peat soil water. Combined use of NPK fertilizers and 25% pineapple residue ash improved nitrogen availability whereas amending NPK with 50%, 70%, and 100% pineapple residue ash were more effective in improving nitrogen uptake, fresh fruit yield, and fruit quality of pineapple. Pineapple residue ash can also have significant liming effect.

A total of 30 bacterial isolates were isolated from soil, rhizoplane, and internal tissue of oil palm roots. The isolates were qualitatively tested for their potential to fix N2, solubilize inorganic P and K, and produce phytohormone indole-3-acetic acid. Of the 30 isolates, six isolates were able to exhibit multiple beneficial traits. All six isolates were then identified based on fatty acid methyl esters profile as Escherichia coli strain EX2, Serratia sp. strain EN1, Pantoea ananatis strain EN3, Bacillus sp. strain EN5, Pantoea ananatis strain EN8 and Pantoea sp. strain EN9. Subsequently, all shortlisted isolates were evaluated for plant growth-promoting potential by using shallot as a test plant. The plant test showed no significant difference (p>0.05) between inoculated and uninoculated plants except for Pantoea sp. strain EN9 inoculation which increased significantly (p<0.05) total root length over uninoculated control. Host specificity and IAA capacity of the isolates may be among the important factors affecting their effectiveness in plant growth promotion.

Present study aimed to determine the influence of yeast supplementation in diets with or without early feed restriction on nutrient digestibility and carcass characteristics of broiler chickens. Three dietary treatments each consisting of three replicates namely 1) control (commercial diet); 2) 0.3% yeast supplement; and 3) 0.3% yeast and early feed restriction at 7 to 14 days of age. Faeces were collected from five days before the end of experiment and later analysed for crude protein, fibre, and fat. At the end of the experiment (day-42), two broilers from each replicate were slaughtered. The present study found that crude protein and crude fat increased at 92.00 ± 1.46% and 96.33 ± 0.42%, respectively (P<0.05), over broilers fed commercial pellet only at 84.50 ± 0.56% and 94.17 ± 0.48%, respectively. However, when employing feed restriction on broilers fed on diets with 0.3% yeast, no further improvement (P>0.05) on nutrients digestibility was observed after yeast supplementation in diets. Dressing and abdominal fat of broiler chickens fed a diet with yeast supplement were different (P<0.05) with control. This study concludes that yeast supplementation improved digestibility of crude protein, crude fat, and dressing and abdominal fat but no improvement when early feed restriction imposed.

Densification of biochar can reduce transportation and handling costs, as well as significantly decrease loss of biochar during soil application. Although the nutrient-rich biochar tablets may be a potential cost-effective slow-release fertilizer in soil, there is a lack of information on characterization of mixtures of rubber tree twigs and rice residues tablets with embedded NPK fertilizer. Objective of this work was to determine the physical and chemical properties of biochar tablets with and without embedded fertilizer. Biochar tablets were produced by blending of charred rice husk, rice straw, rubber tree twigs, and starch and followed by tableting. Their production with embedded fertilizer was similar to production process of tablets without it, except adding the NPK fertilizer to blending phase prior to tableting. Fourier-transform infrared spectra analysis indicates was utilized for determination of presence of ammonium and phosphorus substances in the biochar tablets with embedded fertilizer (BFs). The NPK fertilizer significantly increased tablet density and total contents of nitrogen, phosphorus, potassium, calcium and magnesium. The presence of higher amount of nutrients in BFs suggests that it could release nutrients for plant use.

Present study demonstrated the antibacterial potential of three different body parts, abdomen, carapace and cheliped of mud lobster (Thalassina anomala) which were extracted with methanol and hexane. Three test bacteria were used in this study namely Bacillus cereus, Escherichia coli, and Salmonella enterica. Present study found that in general, methanolic and hexane extracts of different body parts had variable inhibitory responses on different test bacteria with methanolic extract had greater inhibitory response than hexane extract. In methanol extraction, B. cereus significantly had greatest negative impact (p<0.05) on growth after treated with cheliped (21 mm zone of inhibition) extract of mud lobster as compared to carapace (9.2 mm) and abdominal (8.8 mm) extracts of mud lobster. Overall, the growth of S. enterica was much affected with the presence of all methanolic body-part extracts of mud lobster. In hexane extraction, B. cereus growth was not affected with all body-part extracts of mud lobster. However, E. coli and S. enterica were affected with no significantly different (p>0.05) among body-part extracts and between them. Present study concludes that the extracts of mud lobster of all body-part in methanol possess greater inhibitory effect on bacterial growth than extracts in hexane thus the methanolic extract of mud lobster has the potential to be exploited as a natural source of antibacterial agent.

Serum biochemical parameters data was evaluated in broilers fed diets supplemented with hempedu bumi (Andrographis paniculata, AP) ground leaf. Birds (n = 160) were assigned in four treatment groups with five replication and each group contain eight birds. Broilers in the control group were fed the basal diet without additives, the group dietary treatments, Diet AP2 (Basal diet + 2g/kg Andrographis paniculata); Diet AP4 (Basal diet + 4g/kg Andrographis paniculata) and Diet AP8 (Basal diet + 8g/kg Andrographis paniculata). During day-21 and day-42, five birds from each treatment groups were randomly selected for serum biochemical analysis which involve pancreatic, renal, and hepatic functions (aspartate transaminase (AST), alkaline transaminase (ALT), alkaline phosphatase (ALP), glucose, cholesterol, triglycerides, total protein, albumin, urea, sodium, potassium, chlorine, and globulins). Liver morphology was determined after slaughtering two birds and collected the liver samples. Based on these results AP at 8g/kg diet lowered serum cholesterol, glucose and triglycerides. It also maintain the normal structure of liver indicating that no toxic effect from AP supplementation at a rate up to 8 g/kg, it also that AP lowered ALP and ALT in blood of chicken. In conclusion, supplementation of AP at 8g/kg in diet its beneficial effects on health and safe for broiler chicken production.

Hibiscus cannabinus (kenaf) plant is claimed as one of the fast-growing herbaceous plants with the high potential as a fiber or lignocelluloses material which is widely planted in Setiu, Terengganu, Malaysia. However, the stem rot disease was observed to be the most problematic in getting the good yields. Microbes associated with H. cannabinus that showing typical symptoms of rot-like disease were isolated using direct plating techniques. Koch’s postulates proved that Coniella musaiaensis was fungus that caused stem rot disease to kenaf out of four isolated fungi. Plant-pathogen interaction revealed the mechanism of infection by direct penetration of fungus through the outer surface of stems, since present of appressorium on the surface of host (H. cannabinus).

To evaluate the effects of ground leaf of Misai kucing ( Orthosiphon stamineus ) as a dietary supplement on serum biochemical parameters and liver morphology. One hundred and sixty one-day old male broiler chickens (n=160) were distributed into four treatment groups, with five replicates of eight birds in each group: the control group (diet without additives); the group dietary treatments, Diet OS2 (Basal diet + 2g/kg O. stamineus ); Diet OS4 (Basal diet + 4g/kg O. stamineus ) and Diet OS8 (Basal diet + 8g/kg O. stamineus ). After 42 days, 40 birds were randomly selected for serum biochemical profile analysis involving pancreatic, renal, and hepatic functions (urea, sodium, potassium, chlorine, aspartate transaminase (AST), alkaline transaminase (ALT), alkaline phosphatase (ALP), glucose, cholesterol, triglycerides, total protein, albumin, and globulins). Present study found that serum levels of cholesterol, triglycerides, urea, AST, ALT and ALP were significantly lower suggesting that the O. stamineus ground leaf possibly do not cause kidney and liver impairment, mainly, at the higher dosage (8g/kg). Present study concluded that the broiler chicken fed O. stamineus ground leaf at a rate 8 g/kg was the most promising dietary supplement to enhance health without deleterious effects on serum biochemical properties and morphological components of liver. In addition, it reduces abdominal fats and serum cholesterol. This study has provide evident that medicinal plant, O. stamineus can potentially substituted the use of additive synthetic.

The present study was conducted to evaluate the effect of single and dual inoculation of Bacillus cereus strain UPMLH24 and Rhizobium sp. strain AM2 on seed germination and seedling vigour of winged beans (Psophocarpus tetragonolobus). Treatments were as follows: Uninoculated control, Rhizobium sp. AM2, Bacillus cereus UPMLH24, and a combination of Rhizobium sp. AM2 and B. cereus UPMLH24. Present study found that inoculation with B. cereus alone and its combination had significantly increased (p<0.05) root length, shoot length and vigour index of winged bean seedlings as compared to uninoculated control. However, present study indicated that single inoculation with B. cereus UPMLH24 was significantly higher than Rhizobium sp.AM2 +Bacillus cereusUPML24 inoculum in all parameters. In conclusion, single inoculation with Bacillus cereus UPMLH24 or in combination with Rhizobium sp. AM2 have the potential to enhance seed germination and seedling vigour of winged beans and might be suitable to be formulated as a biostimulant.

Citric acid has high economic potential owing to its numerous applications. It is mostly produced by microbial fermentation using Aspergillus niger. In view of surges in demand and growing markets, there is always a need for the discovery and development of better production techniques and solutions to improve production yields and the efficiency of product recovery. To support the enormous scale of production, it is necessary and important for the production process to be environmentally friendly by utilizing readily available and inexpensive agro-industrial waste products, while maintaining high production yields. This article reviews the biochemistry of citric acid formation, choices of citric-acid producing microorganisms and raw materials, fermentation strategies, the effects of various fermentation conditions, citric acid recovery options and the numerous applications of citric acid, based on information drawn from the literature over the past 10 years.

Rhizobacteria have been widely reported with beneficial properties, able to promote growth and yield of various agricultural crops. In the present study, two strains of rhizobacterium Bacillus cereus were tested on its ability to induce and elongate roots of pepper stem cuttings after inoculation. Results showed that B. cereus UPMLH24 inoculation on fresh pepper stem cuttings stimulated root number (55% increase over control), length of longest root (25% increase over control), total root length (87% increase over control), root fresh weight (28% increase over control) and root dry weight (112% increase over control). Present study recommends Bacillus cereus UPMLH24 as a potential candidate in a formulation of a biostimulant for organic and sustainable nursery for pepper production.

Fourteen indigenous rhizobacterial isolates from pepper (Piper nigrum L.) rhizosphere were successfully identified by 16S rRNA sequencing, namely Acinetobacter radioresistens (UPMLH1), Bacillus spp. (UPMLH8, UPMLH23, UPMLH34 and UPMLH43), Bacillus cereus (UPMLH1, UPMLH13, UPMLH24, UPMLH41 and UPMLH42), Bacillus megaterium (UPMLH3 and UPMLH22), Bacillus subtilis (UPMLH5) and Leclercia sp. (UPMLH2). All the identified strains were successfully positioned in the 16S rRNA based phylogenetic tree at the nucleotide and the amino acid sequence levels. Present study found that the relationship structure of translated amino acid phylogenetic tree was simpler than nucleotide based phylogenetic tree. Both phylogenetic trees contained two phyla, Firmicutes and Proteobacteria, with the Firmicutes were the largest proportion of the isolates recovered from this study.

Fusarium wilt is a fungal disease, which affects a broad range of plants including black pepper (Piper nigrum). Fusarium solani f. sp. piperis is a common causal agent of root rots and stem blight in black pepper. F. oxysporum Schl. f. sp. piperis, a less common but an important pathogen of black pepper. The biological approach to control F. oxysporum is becoming popular in many crop plants however there is lack of scientific record in black pepper. Endophytic bacteria were isolated from black pepper roots and cultured on nutrient agar. The bacterial isolates were screened for in vitro antagonistic activity against F. oxysporum through dual culture, mycelial growth, spore germination and double plate tests. Five isolates with promising antifungal activity were further identified through 16S rDNA sequencing. Isolates EB1 and EB2 showed highest antagonism against F. oxysporum mycelia with the percentage of inhibition up to 43% and 41%, respectively. Isolated EB3, EB4 and EB5 produced clearing zones in spore germination test with radii measurements at 12.5-15.0 mm. The antifungal activities apparently involved the secretion of volatile and diffusible bioactive compounds. Analysis of the 16S rDNA sequences suggested the closest identities of the bacterial isolates as Bacillus megaterium, Bacillus cereus, Enterobacter sp. and Bacillus sp. Five endophytic bacteria isolates demonstrated significant control over both mycelia growth and spore germination of F. oxysporum. Some of these bacteria might possess additional beneficial plant growth promoting and insecticidal properties for the development of multi-function products in black pepper farming.

Leaves of Andrographis paniculata and Orthosiphon stamineus were extracted with water, ethanol, methanol and chloroform to assess their potential as antibacterial and antioxidant agents. High performance liquid chromatography analysis showed that the methanolic extracts of A. paniculata and O. stamineus leaves gave the highest amounts of andrographolide and rosmarinic acid, respectively. These leaf extracts exhibited antimicrobial and antioxidant activities and, at the highest concentration tested (200 mg/mL), showed greater inhibitory effects against the Gram positive bacteria Bacillus cereus and Staphylococcus aureus than 10% acetic acid. Andrographis paniculata and O. stamineus methanolic and ethanolic leaf extracts also showed the strongest antioxidant activity as compared with the other extracts tested. The bioactive compounds present in these leaf extracts have the potential to be developed into natural antibacterial and antioxidant agents that may have applications in animal and human health.

The increase in awareness of the public to use inexpensive, safe, organic and environmentally friendly agricultural inputs makes plant growth-promoting rhizobacteria as one of the more attractive biological applications used to reduce or complement the use of synthetic agricultural inputs. In the present study, diligent investigation has been conducted in search of the most promising plant growthpromoting rhizobacteria from pepper (Piper nigrum L.) rhizosphere. As a result of the search, 14 rhizobacteria were isolated from the rhizosphere of the pepper plant (Piper nigrum L.). In vitro analyses showed that the isolates possessed many traits beneficial to agronomy, viz. biological nitrogen fixation, phosphate solubilisation and indole acetic acid (IAA) production. Analyses by 16S rRNA sequencing indicated that the isolates belonged to Acinetobacter radioresistens (UPMLH19), Bacillus cereus (UPMLH1, UPMLH13, UPMLH24, UPMLH41 and UPMLH42), Bacillus megaterium (UPMLH3 and UPMLH22), Bacillus subtilis (UPMLH5), Bacillus spp. (UPMLH8, UPMLH23, UPMLH34 and UPMLH43) and Leclercia sp. (UPMLH2). Phylogenetic analyses indicated that the newly isolated rhizobacteria from P. nigrum were from Firmicutes and Proteobacteria, with the former being more common. In the present study, computational methods were used to predict information within the small subunit 16S rRNA gene from B. cereus strain UPMLH24. The computational methods employed revealed that the small subunit 16S rRNA gene sequence from B.cereus strain UPMLH24 contained several open reading frames that encoded gamma-polyglutamic acid protein, lipoprotein, cytoplasmic protein and ribosomal protein S10. Computational predictions based on protein-protein identity classified seven phyla of organisms associated with small open reading frames of novel B.cereus strain UPMLH24. Plant bioassay technique was used to select the most promising isolates. Three vegetable crop species were used as test plants, namely mustard (Brassica ju

Aim: Auxin, a phytohormone secreted by plant growth-promoting rhizobacteria is one of the direct mechanisms vital for plant growth promotion. A laboratory experiment was conducted to observe the effect of IAA-producing and non-IAA-producing diazotroph Bacillus cereus strains on early growth of shallot (Allium ascalonicum) and mustard (Brassica juncea) plants. Methodology and Results: Treatments evaluated were as follows: Control = uninoculated, no inoculation, UPMLH1 = IAA-producing B. cereus UPMLH1, and UPMLH24 = non-IAA-producing B. cereus UPMLH24. Inoculation with IAA-producing B. cereus UPMLH1 significantly increased shallot adventitious roots (root number and length) and shoot growth (19 to 54% increment). Inoculation of non-IAA-producing B. cereus UPMLH24 did not significantly improve growth of adventitious roots of shallot as compared to uninoculated control, except its shoot (up to 40% increase). However, primary roots and shoot growth of mustard plants significantly increased through inoculation with IAA-producing and non-IAA-producing strains (14 to 73% increment). Conclusion, Significance and Impact of Study: The results indicated that exogenous IAA secreted by B. cereus UPMLH1 might have play an important role in inducing roots of shallot bulbs and it may have a variable promotional effect depending on plant species.

There are increasing applications of diazotrophic rhizobacteria in the sustainable agriculture system. A field experiment on young immature oil palm was conducted to quantify the uptake of N derived from N2 fixation by the diazotroph Bacillus sphaericus strain UPMB-10, using the 15N isotope dilution method. Eight months after 15N application, young immature oil palms that received 67% of standard N fertilizer application together with B. sphaericus inoculation had significantly lower 15N enrichment than uninoculated palms that received similar N fertilizers. The dilution of labeled N served as a marker for the occurrence of biological N2 fixation. The proportion of N uptake that was derived from the atmosphere was estimated as 63% on the whole plant basis. The inoculation process increased the N and dry matter yields of the palm leaflets and rachis significantly. Field planting of young, immature oil palm in soil inoculated with B. sphaericus UPMB-10 might mitigate inorganic fertilizer-N application through supplementation by biological nitrogen fixation. This could be a new and important source of nitrogen biofertilizer in the early phase of oil palm cultivation in the field.

Ten indigenous isolates of Paecilomyces lilacinus (PL), were isolated from two black pepper farms in Sarawak heavily infested with root-knot nematodes (RKN) as an initiative to control RKN problem. All isolates showed varying degree in colonizing female nematodes. In the female nematode bioassay on water agar, both indigenous strains of PL namely PLA, PLB, and a commercial strain, PLM (as positive control) demonstrated highly significant colonization (>90%, P≤0.01) on female. In egg parasitism test, spore suspension (105 spore/mL) of the strains PLA, PLB and PLM exhibited 78.8%, 66.0% and 73.4% parasitism on eggs, respectively. Meanwhile, hatching of nematode eggs incubated in spore suspension of PLA, PLB and PLM for seven days were significantly reduced; 88-89% of eggs were hatch-inhibited as compared to control (26%). This illustrated both local isolates, PLA and PLB are comparable with PLM as biological control agents for managing RKN infestation on black pepper vines.

Inorganic-N fertilizer is the most widely used input in agriculture and it is a major factor that limits crop growth and yield. However, excessive use of inorganic nitrogenous fertilizer could lead to hazardous effect to the agro-environment. Besides that, it would also increase total production cost of the agricultural sector especially in the oil palm industry, the largest income generator to Malaysian agricultural economy. Rapid losses of fertilizer-N through leaching would further increase the cost on oil palm production and make the sector less profitable. In recent times, there is an increased attention to biological nitrogen fixation (BNF) as an alternative or supplement to nitrogenous fertilizers through application of associative N2-fixing rhizobacteria which could be applied to oil palm. These beneficial plant growth promoting rhizobacteria (PGPR) have been reported to be efficient in fixing atmospheric nitrogen and stimulating growth of leguminous and non- leguminous crops. Thus, it could be used as a biofertilizer and bioenhancer for most crops. However, there has been no report on the beneficial effect of PGPR on early growth of young oil palms under field conditions. A field trial using 15N isotope was conducted to estimate the N2 fixing capacity of a single strain N2-fixing rhizobacterium, Bacillus sphaericus UPMB-10, and assess its effects on early growth of young oil palms. Results from a 240-day (D240) field experiment indicated that the Bacillus sphaericus rhizobacterial strain UPMB-10 is a potential biofertilizer for oil palm seedlings with a N2 fixing capacity of 63% Ndfa (N derived from atmosphere) (78 g N2 fixed palm-1) of the total N requirement of young oil palms (equivalent to 12 kg N ha-1 at 148 palms ha-1) over 8 months. B. sphaericus UPMB-10 inoculation stimulated higher N content (125 g palm-1) as compared to the uninoculated control (90 g palm-1) and also promoted a total dry matter accumulation of 11 kg palm-1 in comparison to the con