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This study investigated the phytochemical composition of honey from four species of Malaysian stingless bee i,e. Tetragonula laeviceps, Geniotrigona thoracica, Lepidotrigona terminata, as well as Heterotrigona itama. The measured phytochemical composition was total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity, pH, colour intensity, and mineral element analysis i.e. Magnesium (Mg), Calcium (Ca), Zinc (Zn), Potassium (K), and Sodium (Na). The production of honey by the L. terminata had the highest TPC value (6.74±0.57 mg GAE/100 g FW) while the T. laeviceps possesses the highest TFC value (14.85±3.71 mg QE/100 g FW). In the antioxidant activity measurement, honey from the H. itama obtained the highest percentage of 1,1-diphenyl-2- picrylhydrazyl (DPPH) inhibition (29.52±0.45%) and honey from T. laeviceps displayed the highest value in the Ferric reducing antioxidant power (FRAP) analysis (0.95±0.013 abs). The four distinct stingless bee species’ colour intensity demonstrated the variation of colour intensity in the range of 0.09-0.23 abs mAU. All honey obtained the pH values (4.75-5.03) within the acidic medium. Mg is the major mineral element in all honey samples which is followed by Na, Ca, K, and Zn.

Background: Bambara groundnut is an edible legume that is highly nutritious. This study was carried out to find the effect of nitrogen (N) and phosphorus (P) fertilizers on the growth, yield, nodulation, the proximate and nutritional composition of bambara groundnut [Vigna subterranea (L.) Verdc.]. Methods: During the period of 2018, a glasshouse experiment was conducted in a randomized complete block design (RCBD) at Ladang 15, Faculty of Agriculture, Universiti Putra Malaysia. Different rates of N and P fertilizer were used. Kjeldahl method and HPLC, respectively, determined the protein and amino acid content in seed. Result: N and P fertilizer were found to play a dominating role in increasing the vegetative growth and yield of the plant. Plant height (20.65a), pod number (45.75a) and harvest index (41.61a) increased significantly with the application of N30 + P60 kg ha-1. Application of N30P60 kg ha-1 significantly influenced nodulation and nitrogen yield. Protein, fibre, Mg and amino acid content increased with N30P60 kg ha-1. The application of N30P60 mg kg-1 has increased the growth, yield, nodulation, proximate and nutritional composition of bambara groundnut.

Background Numerous studies have been conducted to investigate the capability of edible coatings for preserving the quality and prolonging the shelf life of fresh/fresh-cut fruits. Evidence has shown that an edible coating could function as a barrier on the fruit surface, modify the internal gas atmosphere, decrease water losses and delay fruit ripening. Efforts have been exerted to introduce new natural coating materials to sustain the safety and quality of fresh/fresh-cut fruits. Scope and approach This review attempts to provide a summary of the recent studies on the application of edible coatings on different fresh/fresh-cut fruit categories, namely pome fruits (apple and pear), citrus, stone fruits, tropical and exotic fruits, berries, melon, and tomatoes. A fundamental theory behind the edible coating treatment and the effect on the physiological, physicochemical, sensory, and antimicrobial properties of fresh/fresh-cut fruits is discussed. The future perspective of this preservation method is also highlighted. Key findings and conclusions Edible coating can be used as an alternative strategy to prolong the shelf life of fresh/fresh-cut fruits. The materials selection for edible coating play a key role in determining its effectiveness and consumers acceptability. The ability of the selected materials in extending the shelf life of fresh/fresh-cut fruits without reducing the sensory and nutritional characteristics are the main challenges in the edible coating techniques, which demands attention for further research.

Background and Objective: The increase in growth after receiving brassinolide may vary between species. The main growth factors which may directly reflect to yield are functional leaf, shoot and root segment. Thus, the aim of this study was to investigate the effect of different concentrations of exogenous application of BL on growth of leaves, shoots and roots segments of fig. Materials and Methods: The experiment was arranged as Split Plot Randomized Complete Block Design (SRCBD) with 4 replications. Two fig cultivars Improved BrownTurkey (IBT) and Masui Dauphine (MD) were considered as a main plot and four level (0, 50, 100 and 200 mL LG1) of BL concentration asa sub plot. Experiment was conducted in an open field at Ladang 15, Faculty of Agriculture, University Putra Malaysia Serdang, Selangor,Malaysia, from May-December, 2017. Data was recorded weekly and monthly. Results: The results showed that growth of fig was affected by brassinolide levels and cultivars. Application of 50-200 mL LG1 BL increased growth of fig on leaves, shoots and roots segments in weekly and monthly observations. There was significant difference treatment of brassinolide and cultivar alone on growth of fig. Inaverage, concentration of brassinolide at 200 ML LG1 resulted highest growth performance of fig. The highest growth value of interaction between brassinolide and fig variety was on treatment of IBT+200 ML LG1. Between the varieties, IBT showed higher growth than MD.Significant negative correlation was noted only on between RL with RAD. Conclusion: The results of this study indicated that growth of fig on leaves, shoots and roots segments was affected by brassinolide levels and cultivars.

Soursop (Annona muricata L.), a climacteric fruit which is rich in bioactive compounds for use its in medicine. It produces an aromatic, sweet-sour and pleasant taste. However, there is a limitation in the fruit being able to reach distant markets. Its quick ripening and accentuated softening properties make it difficult to handle without damage and shorten its postharvest life. In order to reduce lost value during storage life, this study aims to investigate the effect of 1-Methylcyclopropene (1-MCP) treatment on the fruit’s postharvest life including its physiological and physiochemical characteristics. Selected soursop fruits were harvested at 16 weeks after pollination and treated with various concentrations of 1-MCP (0, 400, 800 and 1200 nL/L) at 15°C + 3°C for 24 h and subsequently being stored at ambient temperature (25°C + 3°C). Observations on various physical, physiological, biochemical and antioxidants parameters were recorded at a two-day intervals 6 days of storage. The results showed that respiration rate and ethylene production in 1-MCP treated fruit were lower than those in the control batches. Further, the pulp of 1-MCP treated fruits remained firm and colour was retained throughout the observation period. Soursop treated at different 1-MCP concentration (0, 400, 800 and 1200 nL/L) showed that fruit treated with 400 nL/L had better ripe fruit quality. In addition, 1-MCP treated fruits were able to normally soften at day six after storage. However, antioxidant capacity, total phenolic content, and total flavonoid content of fruits from all treatments were found inconsistent during storage.

The major causes of vase life reduction in cut flowers are the microbial proliferation in vase solution and consequently vascular occlusion preventing water uptakes. In order to control microbial proliferation efficiently, silver nanoparticles (Ag-NPs) are used as an enhancer to assess leaf extracts of Psidium guajava and Andrographis paniculata to alleviate xylem blockage in cut Mokara Red orchid flowers. The basal stem of each flower was re-cut and then pulsed with 0, 5 and 10 mg/L Ag-NPs for 24 h. The floral preservative solutions are comprised of control (125 mg/L 8-hydroxyquinoline citrate, 8-HQC) and double combination leaf extracts (DCLE) of P. guajava and A. paniculata, each at 15 mg/L. The preservative solutions of DCLE with 5 mg/L Ag-NPs had higher rates of solution uptake and trace amounts of bacterial suspension, which were responsible for increasing the vase life of cut Mokara Red Orchid flowers for 15.49 ± 0.15 days, compared to the 8-HQC control treatment 8.73 ± 0.16 days. Therefore, leaf extracts of P. guajava and A. paniculata have the potential as a biocide to minimize microbial populations and prolong the vase life of cut flowers. However, the potential activities of specific antimicrobial compounds to extend the vase life need to be tested.

‘Frangi’ papaya is a F1 hybrid cultivar produced by Malaysian Agrifood Corporation Bhd in 2006. Since then, ‘Frangi’ papaya is a new hybrid and its physiology may differ from another cultivars. Several importer countries, such as Japan and China, have made the vapour heat treatment (VHT) an export requirement for disinfestation of fruit flies in Malaysia. The exporting country is also required to carry out ripening treatments with ethylene before export. Therefore, the objective of this work was to determine the effects of maturity stages (4, 5 and 6) and ethylene treatments on ripening characteristics of vapour heat treated papaya during storage at 25 °C. Papaya fruits were treated with VHT systems. After VHT, the fruits were exposed with 100 µL.L–1 ethylene gas at 20 °C for 24 h. Non-ethylene treated fruits (control) were kept separately at 20 °C for 24 h. After 24 h, the fruits were removed from the ripening rooms, and stored at 25 °C. The ripening characteristics of fruits that reached maturity stages 4, 5, and 6 were recorded. Results showed that the fruits ripened normally at 25 °C with or without ethylene following VHT with respect to peel and pulp color, edible firmness and soluble solids concentration (SSC). Fruits at maturity stage 5 were considered at the edible stage by taking into account the firmness, SSC, titratable acidity, and ascorbic acid contents. It is recommended that no ethylene treatment is needed to ripen vapour heat treated fruits, since the ethylene treatment did not affect the ripening process of the fruits.

Bambara groundnut (Vigna subterranea) has characteristics to grow in the marginal soil and also tolerant into the drought condition and also have potential of nitrogen fixation. Nitrogen is the key plant nutrient that stimulates root and shoot growth. Phosphorus application significantly improves many aspects of plant physiology including photosynthesis, flowering, fruiting and maturation which ultimately result in better yield. Symbiotic nitrogen fixation is a complex process, in which Rhizobium bacteria form a beneficial interaction with a legume crop to fix atmospheric nitrogen and convert it to ammonium for plant uptake. Biological N fixation (BNF) is the natural means to enhance soil fertility status and productivity. Application of nitrogen and phosphorus fertilizer exerted significant effect on root development, photosynthesis, yield contributing character and pod yield of the crop. Bambara Groundnut yields are low due to abiotic and biotic stresses. But with application of nitrogen and phosphorus increase the yield of this crop. It’s seeds contain 63 percent carbohydrate, 19 percent protein and 6.5 percent oil and good source of fibre, calcium, iron and potassium.

This research was conducted to evaluate the effects of calcium chloride (CaCl2) and calcium nitrate Ca(NO3)2 on nutrient concentrations and postharvest quality of papaya fruits. In the first experiment, plant stem height increased significantly after Ca(NO3)2 application compared to CaCl2. The calcium content in the peel and pulp for both sources [CaCl2 and Ca(NO3)2] significantly rose with increasing calcium concentrations, but there was a significantly higher content of calcium in fruit peel and pulp in the CaCl2 treatment. Magnesium and potassium in fruits decreased with increasing calcium concentrations. A reduction in anthracnose lesion diameter in the infected fruit with increasing calcium was observed in both CaCl2 and Ca(NO3)2 treatments. Ethylene production in fruits decreased with increasing calcium concentrations. In the second experiment, only CaCl2 was used as the calcium source, and results showed that the calcium content in fruit peel and pulp significantly increased at higher CaCl2...

Effects of gum arabic (GA) 10% and calcium chloride (CA) 3% on the physiological, biochemical and quality responses of mango ( Mangifera indica L. cv. Choke Anan) fruit were investigated. Fruit were stored at 6 °C and 90% relative humidity for 28 d and then transferred to 25 °C for an additional 5 d shelf life. Significant ( P ≤ 0.05) differences were observed in fruit treated with CA 3% and GA 10% as compared to the control. The combined treatment of CA 3% and GA 10%, significantly alleviated chilling injury, malondialdehyde (MDA) content and electrolyte leakage than the control fruit. This treatment reduced the increase in hydrogen peroxide (H 2 O 2 ) content, superoxide anion (O 2 − ) production rate and enhanced DPPH radical scavenging activity. Furthermore, GA 10% alone or in combination with CA 3% effectively inhibited the loss of total phenolic content and ascorbic acid. The result of transmission electron microscopy confirmed that treated fruit maintained cell membrane integrity. These results suggest that application of GA 10% coating combined with CA 3% might be enhanced low temperature tolerance by improving the antioxidant defense system and reducing oxidative damage of mango fruit.

Calcium (Ca) is a major plant nutrient that affects cell wall and plasma membrane formation and plays a key role in plant growth, biomass production, and function. Ca can be used to decrease fruit decay and increase firmness and shelf life. Different sources and concentrations of foliar-applied Ca were examined for the effects on nutrient concentration and growth of ‘Eksotika II’ papaya (Carica papaya) plants. Papaya seedlings were established in pots and irrigated with a standard nutrient solution in a net house. Four preharvest sprays were applied as foliar applications with three different sources of Ca {calcium chloride [CaCl2], calcium nitrate [Ca(NO3)2], and calcium propionate [Ca(C2H5COO)2]} at four concentrations (0, 60, 120, and 180 mg·L−1). Plant Ca concentration was unaffected by the different Ca sources. However, increased Ca concentration applied to the leaves enhanced plant accumulation of phosphorous and Ca in the plant, but decreased potassium (K) and magnesium (Mg) concentrations in the tissues. Plants that received Ca at 180 mg·L−1 had greater height and diameter than control plants. In a field trial with mature trees, preharvest applications of Ca (0, 4000, and 5400 mg·L−1) in the form of CaCl2 showed that increasing concentrations improved fruit Ca concentration, texture, and flavor; and decreased weight loss, Mg content, and apparent disease incidence of the fruit.

Leafy vegetables such as lettuce grown under different production systems may accumulate different concentrations of nitrate which may reach to the levels potentially toxic to humans. Moreover, nitrate accumulation varies in various plant parts and physiological age of the plant. Therefore, to determine the effect of production system and harvesting stage on nitrate accumulation and quality of butterhead lettuce, a study was conducted considering two lettuce production systems namely hydroponic and organic, and four different harvesting stages such as 35, 38, 41 and 44 days after transplanting (DAT). The experimental design was complete randomized design (CRD) with four replications. Hydroponic and organic systems performed similar in terms of yield, quality and nitrate content of butterhead lettuce. Delaying harvesting can not only increase yield but also can minimize nitrate accumulation and health hazard risk as well. Delay in harvesting stage may result in quality deterioration of lettuce and increased production cost. Thus, a compromise is necessary to consider 41 DAT as the optimum stage to harvest butterhead lettuce with significantly higher reduction of nitrate content in both outer adult leaf blades and young leaves of hydroponic lettuce. Fresh weight, firmness and color of butterhead lettuce at this stage were still acceptable.

Effect of gum arabic (GA) 10% and calcium chloride (CA) 3% on the physiological and biochemical properties of mango (Mangifera indica L. CV. Choke Anan) fruits stored at 6 ± 1 °C and 90 ± 3% relative humidity for 28 days and then transferred to 25 ± 2 °C for 5 days shelf life were investigated. Significant (P ≤ 0.05) differences were observed in fruits treated with GA 10% and CA 3% as compared to control. The combined treatment of CA 3% + GA 10% significantly alleviated the increase in decay incidence. Furthermore, GA 10% alone or combined with CA 3% effectively reduced weight loss, color changes, soluble solid concentration, respiration rate, ethylene production and maintained high firmness, titratable acidity and ascorbic acid. The result of transmission electron microscopy revealed that these treatments also protected the ultrastructure of mitochondria. These results suggest that application of GA 10% coating combined with CA 3% might be a simple and effective technique for preserving mango fruit quality during low temperature storage.

MRQ74, a popular aromatic Malaysian landrace, allows for charging considerably higher prices than non-aromatic landraces. Thus, breeding this profitable trait has become a priority for Malaysian rice breeding. Despite many studies on aroma genetics, ambiguities considering its genetic basis remain. It has been observed that identifying quantitative trait loci (QTLs) based on anchor markers, particularly candidate genes controlling a trait of interest, can increase the power of QTL detection. Hence, this study aimed to locate QTLs that influence natural variations in rice scent using microsatellites and candidate gene-based sequence polymorphisms. For this purpose, an F2 mapping population including 189 individual plants was developed by MRQ74 crosses with 'MR84', a non-scented Malaysian accession. Additionally, qualitative and quantitative approaches were applied to obtain a phenotype data framework. Consequently, we identified two QTLs on chromosomes 4 and 8. These QTLs explained from 3.2% to 39.3% of the total fragrance phenotypic variance. In addition, we could resolve linkage group 8 by adding six gene-based primers in the interval harboring the most robust QTL. Hence, we could locate a putative fgr allele in the QTL found on chromosome 8 in the interval RM223-SCU015RM (1.63cM). The identified QTLs represent an important step toward recognition of the rice flavor genetic control mechanism. In addition, this identification will likely accelerate the progress of the use of molecular markers for gene isolation, gene-based cloning, and marker-assisted selection breeding programs aimed at improving rice cultivars.

Segregation distortion analysis in plant breeding is highly important because deviation factors are occasionally serious barriers for introgression of genes of interest into cultivated species. Also, the identification of major QTLs by high linkage disequilibrium is highly useful for breeders in order for crop improvement programs and the further fine mapping of particular genes. Consequently, simultaneous consideration of segregation distortion and linkage disequilibrium leads to developing fertile hybrids and normal inheritance of agronomically favorable genes. Hence, the goal of this study was to investigate genomic regions known to contain fragrance quantitative trait loci (QTLs) in terms of segregation distortion and linkage disequilibrium pattern, and to seek for a possible relationship between them using codominant markers on chromosomes 3, 4, and 8 in a set containing 189 F2 progenies. For the first time, we discovered the presence and extent of segregation distortion and linkage disequilibrium across the fragrance chromosomal areas of rice. The high frequency of skewed allelic segregations in the chromosomes 3 and 4 supports reports of possible gametic selection (ga) and hybrid sterility (S) genes. Finally, the highest linkage disequilibrium values, the lowest recombination frequency, and the shortest distances were observed in the chromosomal regions without segregation distortion. High linkage disequilibrium correlations between markers at short distances may show that such markers can maintain high linkage disequilibrium with linked QTLs and are influential for both MAS and QTL mapping analysis. Moreover, an indirect relationship between segregation distortion and linkage disequilibrium was detected, and thus linkage disequilibrium maps were introduced as useful diagnostic tools for segregation distortion.

The effects of preharvest application of calcium chloride on ripening, activity patterns of pectin modifying enzymes and overall quality of papaya (Carica papaya L. cv. ‘Eksotika II’) fruits have been investigated. Foliar sprays of 0, 0.5%, 1%, 1.5% and 2% (w/v) calcium chloride were applied six times during the growing season. After harvest, fruits were stored at 12 °C for up to three weeks. Higher calcium concentrations in the sprays coincided with increasing calcium concentrations in peel and pulp tissues, higher firmness and titratable acidity, and reduced respiration rate, ethylene production and soluble solids concentrations, compared with those of the untreated control fruits. The overall quality of fruits treated with calcium was greater than the control fruits. Also, fruits sprayed with calcium had decreased activities of polygalacturonase (PG) and pectin methyl esterase (PME) during storage. Microscopic results confirmed that the middle lamallae of cell walls was more intact in calcium chloride-treated fruits.

Anthracnose is a fungal disease that leads to a serious quality problem on a wide range of fresh produce. The current study attempted to investigate the potential of antifungal activity in Malaysian stingless bee or kelulut honey (KH) against anthracnose disease in papaya. KH was obtained from bee honey collectors from three different regions in Malaysia i.e Selangor, Kelantan and Sarawak. The screening for antifungal activity was performed via poison agar method using in vitro and in vivo assays against postharvest fungus Colletotrichum sp. The presence of the fungus was detected and confirmed by polymerase chain reaction (PCR) as well as a morphological technique. Results indicated 15% concentration of KH exhibited potent inhibitory effects and suppressed the mycelial growth of Colletotrichum sp. The scanning electron microscope (SEM) analysis revealed the rupture of the spores of fungus treated with 15% concentration of KH solution and degradation of hyphal growth. Further study was conducted on the KH solution for the detection of phenolic and flavonoid compounds by using high-performance liquid chromatography (HPLC) with a diode array detector. Results demonstrated that all of the samples contained gallic acid, coumaric acid, ferulic acid, and salicylic acid as phenolics compounds while naringenin and kaempferol as flavonoid compounds, which could contribute to the antifungal potential.

Anthracnose disease of papaya, caused by Colletotrichum gloeosporioides Penz, can cause extensive postharvest losses. The goal of this research was to use pre-harvest calcium applications to reduce anthracnose disease. Six pre-harvest foliar calcium sprays were applied biweekly to papaya trees in experimental orchards at Universiti Putra Malaysia. Additional in vitro and in vivo tests were carried out to test the effect of calcium on fruit calcium content, spore germination, mycelial growth and disease severity. Calcium chloride at 1%, 1.5% and 2.0% concentrations significantly decreased spore germination. Calcium content of papaya fruit was significantly increased by calcium sprays at a concentration of 2.0% in 2012 and 2013. In vivo studies showed that increasing calcium content in fruit by calcium sprays at 1.5 and 2.0% concentrations significantly reduced anthracnose incidence of fruits during five weeks storage at 12 ± 2 °C, and delayed initiation of disease symptoms by four weeks.

Postharvest decay causes decreased in both quantity and quality of fruits. It is also one of the major constraints in papaya production and exports. Anthracnose caused by Colletotrichum gloeosporioides was the most prevalent postharvest fungal disease attacking ‘Frangi’ papaya, where disease incidence and severity was recorded as 90-98 and 25-38%, respectively and the magnitude increased as the fruits ripened. Conventional fungicide treatment is losing popularity due to high residual problem and detrimental to the environment. Thus, a study was conducted to look for a suitable strain of yeast that can substitute fungicides in controlling the disease with the objectives to select and test the ability of epiphytic yeast isolated from papaya fruit, leaf, petiole and trunk in controlling anthracnose onset after harvest. A total of 110 different strains of yeasts were obtained and 29 yeasts isolated showed antagonistic activities against C. gloeosporioides in vitro. Out of 29 yeasts, only five strains YK, YC, YT, YA and YW showed highest percentages inhibition of radial growth (70.3, 60.8, 59.5, 59.5 and 59.5%, respectively) in dual culture assay. Further assays were done in vitro and in vivo in order to confirm the antagonist activities of the yeasts by referring to percentage of disease reduction and inhibition of mycelial growth. Only two strains, YA and YK showed higher potential in controlling anthracnose in in vivo and in vitro test. Based on these results, additional studies on identification and modes of action of the most potential antagonistic yeast(s) to control postharvest anthracnose disease will be conducted.

Extracts from seeds and leaves of Jatropha curcas have shown molluscidal, insecticidal and fungicidal properties. J. curcas extracts were found to inhibit the mycelium growth of Colletotrichum musae that causes anthracnose disease in bananas. The antimicrobial activity of crude methanol extracts of J. curcas fruits, pulp and seeds were investigated. J. curcas fruits, pulp and seeds were collected from the farm of Universiti Putra Malaysia. The samples were air dried at ambient temperature, then oven-dried to remove the residual moisture. Equivalent amounts of each ground sample of the J. curcas fruits, pulp and seeds were soaked in methanol solvent and left to stand for 7 days before being filtered and evaporated. The extract was spread over potato dextrose agar (PDA) medium under an aseptic condition and incubated. The zone of inhibition of mycelial growth (mm) around the disc was measured. Both J. curcas seed and pulp extracts had higher antifungal activity than whole fruit extract. J. curcas seed extract showed significant antifungal activities with growth inhibition zone of 5.6 mm or equivalent to 78.87% inhibition followed by pulp with zone of 7.4 mm or equivalent to 72.07%, and whole fruits with zone of 14.2 mm or equivalent to 46.42% as compared to the control with zone of 26.5 mm or equivalent to 100%. Active microbial components in J. curcas have the potential of an antifungal compound to control Colletotrichum gloeosporioides which causes anthracnose disease in papaya in vitro. Key words : Methanol extracts, inhibition zone, postharvest pathogen.

Till now, herbicide seems to be a cost effective tool from an agronomic view point to control weeds. But long term efficacy and sustainability issues are the driving forces behind the reconsideration of herbicide dependent weed management strategy in rice. This demands reappearance of physical and cultural management options combined with judicious herbicide application in a more comprehensive and integrated way. Keeping those in mind, some agronomic tools along with different manual weeding and herbicides combinations were evaluated for their weed control efficacy in rice under aerobic soil conditions. Combination of competitive variety, higher seeding rate, and seed priming resulted in more competitive cropping system in favor of rice, which was reflected in lower weed pressure, higher weed control efficiency, and better yield. Most of the herbicides exhibited excellent weed control efficiency. Treatments comprising only herbicides required less cost involvement but produced higher net benefit. On the contrary, treatments comprising both herbicide and manual weeding required high cost involvement and thus produced lower net benefit. Therefore, adoption of competitive rice variety, higher seed rate, and seed priming along with spraying different early-postemergence herbicides in rotation at 10 days after seeding (DAS) followed by a manual weeding at 30 DAS may be recommended from sustainability view point.

Kangkong, especially the upland type (Ipomoea reptans) is popularly consumed as a vegetable dish in the South East Asian countries for its quality related to Vitamins (A and C) and crude fiber contents. Higher fiber contents would prevent from the occurrence of colon cancer and diverticular disease. With young stem edible portion, its cell number and size contribute to the stem crude fiber content. The mathematical approach of allometry of cell size, number, and fiber content of stem could be used in determining the 'best' plant density pressure in producing the quality young stem to be consumed. Basically, allometry is the ratio of relative increment (growth or change) rates of two parameters, or the change rate associated to the log of measured variables relationship. Kangkog grown equal or lower than 55 plants m-2 produced bigger individual plant and good quality (physical) kangkong leafy vegetable, but with lower total yield per unit area as compared to those grown at higher densities.

Management of anthracnose caused by Colletotrichum spp. is the most important issue for the tropical fruit industry because of resulting financial losses. Antifungal effects of gum arabic (GA) (10%), lemongrass oil (LG) (0.05%), cinnamon oil (CM) (0.4%), and their combinations were investigated in vitro and in vivo for controlling postharvest anthracnose of banana and papaya. LG at 0.05% and 0.4% CM showed fungicidal effects against Colletotrichum musae and Colletotrichum gloeosporioides, causal organisms of banana and papaya anthracnose, respectively. GA alone did not show any fungicidal effects while the combination of 0.05% LG and 0.4% CM with Ten percent GA alone showed more fungicidal effects. However, potato dextrose agar (PDA) medium modified with 10% GA combined with 0.4% CM showed the most promising results among all treatments against C. musae and C. gloeosporioides in suppressing the mycelial growth (73.4%) and (70.0%) and spore germination inhibition (88%) and (85%), respectively. In vivo studies also revealed that 10% GA combined with 0.4% CM was the optimal concentration in controlling decay (80%) and (71%), showing a synergistic effect in the reduction of C. musae and C. gloeosporioides, respectively, in artificially inoculated bananas and papayas. The results regarding quality evaluation also confirmed the efficacy of 10% GA combined with 0.4% CM coatings since ripening was significantly delayed, in terms of percentage weight loss, fruit firmness, soluble solids concentration and titratable acidity. The results suggest the possibility of using 10% gum arabic combined with 0.4% cinnamon oil as a biofungicide for controlling postharvest anthracnose in major tropical fruit such as banana and papaya.

Mature green stage (Index 2) papaya cv Eksotika II fruits were treated either with 2.5% calcium chloride infiltration, 0.75% chitosan coating, calcium infiltration at 2.5% then subsequently with chitosan coating at 0.75% or untreated fruits as the control. The fruits were then stored at 13±1°C for 35 days. Calcium infiltration was observed to be effective in maintaining the firmness with a slight effect on the weight loss by 2.9 folds and 2.8%, respectively compared to the control. Chitosan coating had less effect on maintaining firmness (2 folds) but gave better effect in preventing weight loss (5.3%). Chitosan coating treatment markedly slowed the ripening of papaya as shown by their retention of weight loss, delayed changes in their external color and other quality aspects. Calcium infiltration and subsequently chitosan coating as a combined treatment further extended the storage life up to 35 days with better retention of fruits firmness and water loss control compared to the treatments mentioned.

When Cavendish banana (Musa acuminata ’Williams') is ripened at tropical ambient temperature (27°C) the peel fails to degreen although the pulp has softened. However, the peel will degreen to a yellow colour when the fruit is ripened at 18°C. The inability of the peel to degreen could be because of the retention of thylakoid membranes in the plastids and chlorophyll during the ripening process. A study was carried out to investigate the relationships between plastid ultrastructure, chlorophyll content, and peel colour of Cavendish banana ripened at 18±2°C (C18) and 27±2°C (C27). The peel of Cavendish banana underwent complete degreening when the fruit was ripened at a temperature of 18°C to produce a yellow fruit at ripening stage (RS) 6, after 9 days of treatment. In contrast, bananas exposed to 27°C failed to degreen. By day 5 after ripening initiation, the pulp had softened to eating‐ripe in those fruit and brown specks appeared on the fruit peel indicating that senescence had begun. Transmiss...

Orchids possess a very special place amongst ornamental plants. But high ethylene sensitivity and early flower senescence of orchid result in a short vase life and rapid quality deterioration which is of great concern for the growers, traders and consumers. An attempt was made to study the influence of 1-methylcyclopropene (1-MCP) (0 and 300 nL L–1) and аquеous ozone (0 and 5.2 nL L–1) in prolonging vase life and maintaining quality of two cut orchid hybrids Dendrobium 'Darren Glory' (DDG) and Mokara “Calypso Jumbo” (MCJ). Results showed that orchid hybrids exhibited differences in their ethylene sensitivity, vase life, 1-aminocyclopropane-1-carboxylic acid (ACC) content and ACC oxidase activities. Pre-treatment with 1-MCP resulted in reduced ethylene production, vase life, ACC content and ACC oxidase activities, but increased bud opening %. Pre-treatment with аquеous ozone failed to influence all those parameters except bud opening %. Interaction effects of hybrid and 1-MCP were significant for ethylene production, hybrid and ozone for vas life, 1-MCP and ozone for bud opening %, and hybrid, 1-MCP and ozone for ethylene production and vase life. Aqueous ozone markedly contributed to the inhibition of microbial growth in vase solution. Pre-treatment of the cut orchid flowers with 300 nL L–11-MCP, followed by using 5.2 mg L–1 aqueous ozone as the vase solution could be recommended to maintain quality and extend vase life of both the DDG and MCJ orchid hybrids.

Escherichia coli O157:H7 is classified as biological hazard that can produce a bloody diarrhea due to its toxins. While nitrate in vegetables is classified as a chemical hazard if ingested greater than limit and risk getting gastrointestinal cancer and methemoglobinaemia. A study was conducted to obtain the information on E. coli O157:H7 contamination and nitrate content in Butterhead lettuce from local suppliers. The number of colonies E. coli O157:H7 from the lettuce was enumerated using standard plate count and the nitrate content was measured using nitrate meter. From the experiment, it was found that E. coli O157:H7 contamination of Butterhead lettuce in Malaysia is still within the safe limit for the consumers while the nitrate content was distributed differently between leaf structures; midrib, outer adult leaf blade and young leaves. Lettuce midrib and outer adult leaf blade had a higher concentration of nitrate compared to the young leaves.

When a phenotype of interest is associated with an external/internal covariate, covariate inclusion in quantitative trait loci (QTL) analyses can diminish residual variation and subsequently enhance the ability of QTL detection. In the in vitro synthesis of 2-acetyl-1-pyrroline (2AP), the main fragrance compound in rice, the thermal processing during the Maillard-type reaction between proline and carbohydrate reduction produces a roasted, popcorn-like aroma. Hence, for the first time, we included the proline amino acid, an important precursor of 2AP, as a covariate in our QTL mapping analyses to precisely explore the genetic factors affecting natural variation for rice scent. Consequently, two QTLs were traced on chromosomes 4 and 8. They explained from 20% to 49% of the total aroma phenotypic variance. Additionally, by saturating the interval harboring the major QTL using gene-based primers, a putative allele of fgr (major genetic determinant of fragrance) was mapped in the QTL on the 8th chromosome in the interval RM223-SCU015RM (1.63 cM). These loci supported previous studies of different accessions. Such QTLs can be widely used by breeders in crop improvement programs and for further fine mapping. Moreover, no previous studies and findings were found on simultaneous assessment of the relationship among 2AP, proline and fragrance QTLs. Therefore, our findings can help further our understanding of the metabolomic and genetic basis of 2AP biosynthesis in aromatic rice.

Developing fragrant rice through marker-assisted/aided selection (MAS) is an economical and profitable approach worldwide for the enrichment of an elite genetic background with a pleasant aroma. The PCR-based DNA markers that distinguish the alleles of major fragrance genes in rice have been synthesised to develop rice scent biofortification through MAS. Thus, the present study examined the aroma biofortification potential of these co-dominant markers in a germplasm panel of 189 F2 progeny developed from crosses between a non-aromatic variety (MR84) and a highly aromatic but low-yielding variety (MRQ74) to determine the most influential diagnostic markers for fragrance biofortification. The SSRs and functional DNA markers RM5633 (on chromosome 4), RM515, RM223, L06, NKSbad2, FMbadh2-E7, BADEX7-5, Aro7 and SCU015RM (on chromosome 8) were highly associated with the 2AP (2-acetyl-1-pyrroline) content across the population. The alleles traced via these markers were also in high linkage disequilibrium (R(2) > 0.70) and explained approximately 12.1, 27.05, 27.05, 27.05, 25.42, 25.42, 20.53, 20.43 and 20.18% of the total phenotypic variation observed for these biomarkers, respectively. F2 plants harbouring the favourable alleles of these effective markers produced higher levels of fragrance. Hence, these rice plants can be used as donor parents to increase the development of fragrance-biofortified tropical rice varieties adapted to growing conditions and consumer preferences, thus contributing to the global rice market.