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The non-edible parts of Moringa oleifera, such as stems, branches or leaf petioles, have often been discarded while the leaves are consumed as a vegetable or are used to produce organic fertilizer. This study aimed to determine the optimal conditions for producing Moringa organic fertilizer (MOF) from previously unused parts and to compare these fertilizers with cow manure and bio-organic fertilizer. Seventy kilograms of the unused Moringa parts were blended with fifty kilograms of manure, 0.2 kilogram of Trichoderma-based product and two kilograms of superphosphate. The mixture was incubated at different intervals, including 5, 7 or 9 weeks. Next, the effects of MOF on the growth, yield, ascorbic acid content and Brix of lettuce and mustard spinach were also determined and compared with other organic fertilizers (cow manure and bio-organic fertilizer). Results of the study revealed that 25 tons per ha of MOF were significantly superior to those treated with cow manure and bio-organic fertilizer in the case of vegetable yields. Further, 7 weeks of MOF incubation was found suitable to produce an optimal yield during the various incubation period. These results suggested that the Moringa non-edible parts can make organic fertilizer and enhance growth, yield, and leafy vegetable production.

Biofertilizers produced from organic materials help to promote the growth, and yield quality of crops and is more environmentally friendly than chemical fertilizers. Moringa oleifera is a leafy vegetable whose leaves are also used to make biofertilizers. The use of moringa non-edible parts in biofertilizer preparation remains under-explored. In this study, a procedure to produce moringa foliar biofertilizer (MFB) from non-edible parts was developed. The effect of composting time (3 to 4 months) on the quality of MFB was investigated, and four-month incubation was found suitable for biofertilizers yield with the highest nitrogen content and optimal pH. Furthermore, the influences of MFB doses (20 to 100 mL per Litre) on the growth of lettuce and mustard spinach were studied. The yield of these leafy vegetables was the highest at 100 mL per Litre of MFB spray. Finally, MFB was compared with other commercial foliar sprays, including chitosan fertilizer and seaweed fertilizer. Each foliar treatment was applied every five days until five days before harvest. Plant height, the number of leaves, canopy diameter, leaf area index, actual yield, ascorbic acid content, and Brix were found to be similar in lettuce sprayed with MFB, chitosan, and seaweed fertilizers. In conclusion, the application of MFB promoted the growth and yield of mustard spinach.

Background: Moringa oleifera is a vegetable widely consumed because of its nutritional benefits such as proteins, vitamins minerals, antioxidant compounds, and vitamin E. While the plant leaves have been utilized to produce organic fertilizer or bio-extract, other parts such as stems, branches, or leaf petioles have often been discarded as waste. Methods: The present study evaluated different ratios (1:10; 1:20; 1:30; 1:40 and 1:50) and types of bio-foliar fertilizers (Moringa bio-foliar fertilizer, chitosan, and seaweed fertilizers) on yield, and quality in mustard green. The pot and field experiments were conducted in the spring seasons of 2019 and 2020 in completely randomized design using three replications. Result: The results showed that the mustard green yield and quality were affected by ratio and type of bio-foliar fertilizer in both seasons. Highest yield and quality was found for application of moringa bio-foliar fertilizer. The nitrate accumulation value (147.3 mg kg-1) found were also higher for moringa bio-foliar fertilizer but lower than the standard threshold. A strong relationship was found between economic yield (R2 = 0.82 to 0.95 in pots and field experiment (R2 = 0.78 to 0.81). In conclusion, moringa bio-foliar fertilizer at spraying ratio of 1:10 can be used to achieve higher yield and quality for mustard green.

Papiliotrema huenov was previously reported to be highly tolerant of a range of extremely toxic heavy metals. This study aimed to identify the potential of P. huenov to remove manganese and copper from aqueous solution. Physical conditions which affect removal of Mn(II) and Cu(II) were determined. Optimal temperature for adsorption of both metal ions was 30 °C, and optimal pH for maximum uptake of Mn(II) and Cu(II) were 5 and 6, respectively. Under these conditions, living cells of P. huenov accumulated up to 75.58% of 110 mg/L Mn(II) and 70.5% of 128 mg/L Cu(II) over 120 h, whereas, the removal efficiency of metal ions by dead cells over 1 h was 60.3% and 56.5%, respectively. These results indicate that living cells are more effective than dead biomass for bioremediation, but that greater time is required. The experimental data extends the potential use of P. huenov in biosorption and bioaccumulation of toxic heavy metals to copper and manganese, two of the most common industrial contaminants.

Muskmelons are currently grown in several areas of Vietnam for domestic and international consumer markets. The fruit grows well in greenhouses in soil or soilless substrate such as coconut peat. Researchers in Vietnam are investigating the growth of muskmelons in a range of organic by-products. In this study, spent mushroom substrate was recycled for use as an organic substrate and to evaluate the growth, quality, and yield of three muskmelon varieties including RZ F1, PN 128, and TL3 in greenhouses over three months. The substrate was incubated for one month before use and contained 45% spent mushroom substrate, 30% manure, 7.7% rice husks, 1.5% phosphorus, 0.2% commercial Trichoderma (Tribac), 0.1% rice bran, 15% sand, and 0.5% micronutrients and water. Following incubation, the substrate had optimal pH for the growth of muskmelon and the concentration of nutrients and beneficial microorganisms had increased significantly. The growth of RZ F1 and TL3 cultivars was significantly better than PN 128 in terms of growth, fruit quality, and yield. Specifically, RZ F1 and TL3 species took 78 days and 75 days to complete their life cycle produced 1.76 kg and 1.62 kg of fruit, had a pericarp thickness of 4.0 cm, and possessed 14.20o Brix and 14.88o Brix of soluble solid content, respectively. These findings suggest that agricultural by-products, such as spent mushroom substrate, could be a valuable resource for the culture of muskmelons in Vietnam.

Background: The internal transcribed spacer (ITS) of nuclear ribosomal DNA is one of the most commonly used DNA markers in plant phylogenetic and DNA barcoding analyses, and it has been recommended as a core plant DNA barcode. To compare and find out the analysis genetic diversity difference some pepper individuals collected in different localities in Vietnam when using the ITS of nuclear ribosomal DNA. The ITS gene region from the nuclear genomes were tested for their suitability as DNA barcoding regions of thirty-nine pepper individuals. Universal primers were used, and sequenced products were analyzed using the Maximum Likelihood method and Tamura-Nei model in the MEGA X program.Results: We did not observe high variability in intraspecific distance within the ITSu1-4 gene region between individuals, ranged from 0.000 to 0.155 (mean = 0.033). The size of the gene region has fluctuated from 667 to 685 bp between different individuals with the percentage (G + C) contained in the ITSu1-4 gene region was ranged from 54.776% to 60.805%, mean = 60.174%. The values of Fu’s Fs, D, Fu and Li’s D* and F* were negative as well (Fs = -0.209, D = -1.824; P < 0.05, D* = -1.205; not significant, P > 0.10 and F* = -1.699; not significant, 0.10 > P > 0.05), indicating an excess of recently derived haplotypes and suggesting that either population expansion or background selection has occurred. The value Strobeck’s S the obtained between individuals in a population is high (S = 0.684). The results of evolutionary relationships of taxa obtained 3 groups with the highest value of Fst is shown in the pairs of groups II and III (Fst = 0.151), and the lowest is in groups II and I (Fst = 0.015). All of the new sequences have been deposited in GeneBank under the following accession numbers MZ636718 to MZ636756.Conclusions: This database is an important resource for researchers working on Species of pepper in Vietnam and also provides a tool to create ITSu1-4 databases for any given taxonomy.

In Vietnam, bacterial wilt, caused by R. solanacearum, is a major threat to many important field crops. Disease management strategies suggested in the past have remained ineffective. Phylotype analysis and genetic diversity among Vietnamese R. solanacearum is unknown. The present study was conducted to investigate the relationship among isolates of R. solanacearum in the tomato production areas in Vietnam, to analyze genotypic characteristics, to characterize the phylotypes of the isolates and to determine their aggressiveness. All 207 R. solanacearum strains collected from tomato plants in 12 provinces in Vietnam belonged to Asian Phylotype I. All isolates belong to biovar 3, except for isolate Rs86 collected from Ninh Thuan, which belonged to biovar 4. A total of 52 isolates representing 12 origins (provinces) and two Taiwanese strains were selected to investigate genetic diversity and their genetic relationship by using RAPD markers. Based on the unweighted pair group method of arithmetic means endrogram and STRUCTURE results, 54 isolates were grouped into three main clusters. Cluster I includes 3 isolates obtained from Lam Dong province and 1 isolate collected from Tien Giang province. Cluster II had wide distribution from the northern to the southern part of Vietnam. This cluster could be divided into 3 sub-clusters and these sub-clusters were largely separated according to geographical distribution. Sub-cluster IIa consisted of five isolates from Lam Dong province. One isolate from Thai Binh and two isolates from Hai Duong grouped in sub-cluster IIb. Cluster IIc was found only in Hai Phong. Cluster III had highest variation with two sub-clusters. Eight isolates from Southern part, 5 isolates from Nghe An and 2 reference isolates from Taiwan were grouped in sub-cluster IIIa, while 14 isolates mainly from Northern part (Ha Noi, Nam Dinh, and Thai Binh) were grouped in sub-cluster IIIb. Isolates collected in Hai Duong, Hai Phong and Nam Dinh showed higher virulence than those on tomato. The results demonstrated that R. solanacearum isolates even though similar in genetic background do not necessarily cause similar virulence. This is the first report on genetic diversity and aggressiveness of Vietnamese R. solanacearum isolates in tomatoes.

This study reports the isolation of a potential probiotic lactic acid bacteria (LAB) from fermented Solanum macrocarpon food and evaluates shrimp bacterial pathogens' inhibition. The isolate was determined by identifying the inhibition zone against Vibrio parahaemolyticus with an antagonistic activity of 360 AU/mL. Molecular identification based on 16S rRNA indicated that the isolate belongs to the Pediococcus genus, named as Pediococcus pentosaceus HN10. The isolate exhibited effective inhibitory ability against various pathogenic including antibiotic-resistant Vibrio spp., Escherichia coli ATCC 85922 and Staphylococcus aureus ATCC 25023. P. pentosaceus HN10 showed potential probiotic properties such as strong salt tolerance, low pH and bile salts resistance, autoaggregation and coaggregation activities. P. pentosaceus HN10 was negative for β-hemolytic and amino acid decarboxylase. Antibiotic resistance assay showed that this strain was sensitive to ampicillin and chloramphenicol. P. pentosaceus HN10 expressed strongly antioxidant activity. In vivo challenge to V. parahaemolyticus in shrimp model indicated P. pentosaceus HN10 enhanced survival rate, weight gain as well as reduced the number of Vibrio in shrimp intestine tract. Overall, this study suggests that P. pentosaceus HN10 could be applied as a supplementation feed for shrimp to minimize pathogenic bacteria's negative effect.

Moringa (Moringa oleifera Lam.) is a tree species with known value for food, medicine and water treatment. This study was conducted to: 1) evaluate promising moringa accessions from the World Vegetable Center; 2) select accessions adapted to growing conditions in central Vietnam; and 3) determine the influence of soil types, plant density and pruning height on biomass yield of moringa. The results showed that moringa accession VI08718 is the most adapted for growing in central Vietnam. It gained the highest yield (96.1 g plant-1) and highest mean number of branches at each harvest (3.9 branches). Moringa can grow in any soil type but it gained highest yield in alluvial soil (108.0 g plant-1). Biomass yield of moringa grown in sandy soil and fallow sandy soil was lower than in other soil types. However, improvement of sandy soil and fallow sandy soil resulted in high biomass yield comparable to yield in alluvial soil. Plant density of 160,000 plants ha-1 produced the highest yield (8.3 kg plot-1), whereas plants pruned at 55 cm from the soil surface obtained the highest yield (10.3 kg plot-1).

We report the development of a codominant sequence characterized amplified region (SCAR) marker linked to bacterial wilt resistance in tomato line Hawaii 7996. Bulked segregant analysis was employed for rapid identification of RAPD markers linked to resistance genes. Genomic DNA from six resistant F9 recombinant inbred lines (RILs) and six susceptible F9 RILs, which derived from a cross between S. lycopersicum Hawaii 7996 (resistant parent) and S. pimpinellifolium WVa 700 (susceptible parent) were pooled in to an R-pool and an S-pool, respectively. A total of 800 RAPD primers were screened and only six primers (UBC#176, 205, 287, 317, 350, and 676) showed polymorphism between R- and S- pools. Of these, only two markers UBC#176 and 317 revealed a 100% linkage in the individual plants comprising the contrasting bulks. Of these, the marker UBC#176 was converted into a codominant SCAR marker and designated as SCU176-534. The marker SCU176-534 was confirmed by genotyping the individual of the R- and S- pools and gave the same result as UBC#176. When the marker SCU176-534 was further validated for association with resistance and its potential for maker-assisted selection (MAS) in 92 tomato lines and cultivars, the results showed that none of these carries the resistance gene. Thus, SCAR marker SCU176-534 can be used in early selection of resistant lines when Hawaii 7996 is used as a parent in a breeding program.

Random amplified polymorphism DNA (RAPD) and bulk segregant analysis (BSA) approaches were used to characterize the molecular marker linked to the Phytophthora infestans resistance gene Ph-3 in tomato. A total of 800 RAPD primers were screened. One RAPD marker UBC#602 was identified to be tightly linked to the Ph-3 gene. The marker was successfully converted into a co-dominant sequence characterized amplified region (SCAR) marker. The SCAR marker SCU602 was used to ana- lyze 96 F2 progenies and fitted the expected 1:2:1 Mendelian segregation ratio. Forty one tomato inbred lines were screened using the SCAR marker in com- parison with a reference marker linked to the Ph-3 gene and both markers gave the same results. SCU602 was further validated for association to resis- tance and its potential in MAS in 72 tomato lines and cultivars. The marker identified three genotypes har- bouring the resistance allele. This SCAR marker can be used in breeding programs for the selection of the Ph-3 gene for Phytophthora infestans resistance.

Phytopthora root rot in pepper (C. annuum) is caused by Phytophthora capsici L., which exhibits a high level of pathogenic diversity. Resistance to this disease is conditioned by a number of quantitative trait loci. Pyramiding resistance alleles is desirable and could be simplified by the use of molecular markers tightly linked to the resistance genes. The purpose of this study was development of molecular markers linked to Phytophthora root rot resistance. An F8 recombinant inbred line (RIL) population derived from a cross between YCM334 and a susceptible cultivar ‘Tean’ was used in combination with bulk segregant analysis utilizing RAPD and conversion of AFLP markers linked to Phytophtora root rot resistance into sequence-characterized amplified region (SCAR) markers. In conversion: one marker was successfully converted into a co-dominant SCAR marker SA133_4 linked to the trait. In bulked segregant analysis (BSA): three RAPD primers (UBC484, 504, and 553) produced polymorphisms between DNA pools among 400 primers screened. Genetic linkage analysis showed that the SCAR and RAPD markers were located on chromosome 5 of pepper. Quantitative trait locus (QTL) analysis showed that the SA133_4 and UBC553 were linked to Phytophtora root rot resistance. These markers were correctly identified as resistant or susceptible in nine promising commercial pepper varieties. These markers will be beneficial for marker-assisted selection in pepper breeding.

Quantitative trait loci (QTL) for resistance to phytophthora root rot caused by Phytophthora capsici were investigated using two Korean P. capsici isolates and 126 F8 recombinant inbred lines derived from a cross of Capsicum annuum line YCM334 (resistant parent) and local cv. Tean (susceptible parent). The experimental design was a split plot with two replications. Highly significant effects of pathogen isolate, plant genotype, and genotype × isolate were detected. QTL mapping was performed using a genetic linkage map covering 1486·6 cM of the pepper genome, and consisted of 249 markers including 136 AFLPs (Amplified Fragment Length Polymorphisms), 112 SSRs (Simple Sequence Repeats) and one CAPS (Cleaved Amplified Polymorphic Sequence). Fifteen QTLs were detected on chromosomes 5 (P5), 10 (P10), 11 (P11), Pb and Pc using two data processing methods: percentage of wilted plants (PWP) and relative area under the disease progress curves (RAUDPC). The phenotypic variation explained by each QTL (R2) ranged from 6·0% to 48·2%. Seven QTLs were common to resistance for the two isolates on chromosome 5 (P5); six were isolate-specific for isolate 09-051 on chromosomes 10 (P10) and Pc, and two for isolate 07-127 on chromosomes 11 (P11) and Pb. The QTLs in common with the major effect on the resistance for two isolates explained 20·0–48·2% of phenotypic variation. The isolate-specific QTLs explained 6·0–17·4% of phenotypic variation. The result confirms a gene-for-gene relationship between C. annuum and P. capsici for root rot resistance.

The Bs2 gene of pepper (Capsicum spp.) confers resistance to the most commonly detected races of Xanthomonas campestris pv vesicatora (Xcv). Using information from a published database, we developed gene-based markers for selection of Bs2 in pepper. High polymorphism was detected in exon 3, intron 2 and 3’-UTR of the Bs2 gene. The three regions were sequenced and numerous SNPs and In/Dels were identified between resistant and susceptible inbred lines. Seven SNPs were selected to develop SNP markers using the tetra-primer amplification refractory mutation system-PCR methodology (Tetra-primer ARMS-PCR). One SNP (G/C) was used to develop a molecular marker that can perfectly identify the presence of the bacterial spot resistance. The gene-based markers were further validated to test association with resistance in 80 lines and cultivars. The markers successfully identified a bell pepper commercial cultivar 62-2 that harbors the Bs2 gene. The successful development of the markers in this study provides a useful tool for MAS to screen the Bs2 gene in pepper.

The agronomical characteristics of 14 induced pepper accessions from Korea were evaluated in spring-summer in 2015 at Thua Thien Hue in order to select pepper lines having high yield and good adaptation under local conditions for introducing new cultivar to enhance plant productivity and quality. Most of the accessions showed growth duration suitable to cropping pattern in Thua Thien Hue. Large variation in agronomical characteristics, such as plant height, number of leaves and branches, stem and flower color and fruit shape were observed among these induced pepper accessions. Plant height of all induced pepper accessions was higher than control check, ranging from 49.2 cm to 105.0 cm. YT2-1 had the highest fruit set rate (80.38%). All pepper accessions had higher yield compared with the control check (1.42 tons/ha), ranging from 3.71 tons/ha (YT4-1) to 28.34 tons/ha (YT4-3). YT1-2 had good characteristics and good quality. YT1-1 showed high resistance to insects and diseases. These accessions are potentially useful for breeding programme.

Sponge gourd varieties having aroma after cooking have been degenerated because of cross pollination. Collection and evaluation of sponge gourd germplasm are needed for conservation and breeding of high quality varieties. The objective of the study was to identify varieties having high yield, good quality and aroma under local conditions. Ten promising sponge gourd accessions, including A2, A6, A7, A13, A16, A17, B29, B30, HN and QN were evaluated for growth, morphological traits, fruit quality and yield. The experiment was carried out in Hue University of Agricultural and Forestry from June to October in 2014. The results showed that all promising accessions grew well. Different morphological traits were observed among promising lines. Yield of accessions A7, A13 and A17 were higher than the others. Only fruits of accession B29 had aroma after cooking. These lines can be used in sponge gourd breeding programs.

The four F1 hybrid tomato lines (CT2011, CW2011, TS2011, and CLN2011) and two commercial F1 hybrid tomato cultivars used as control (TN52 and TN561) were evaluated for yield and yield components. The efforts were made to minimize reliance on the import of hybrid seed. The experiment was laid out in randomized complete block design (RCBD) with three replications in spring-summer season 2015. Data was recorded on five plants for each replication. The results indicated that all of F1 tomato hybrid lines grew well under Thua Thien Hue condition. CT2011 had the highest plant height, followed by TS2011 and CLN2011. CT2011 is a cherry type and obtained the highest percentage of fruit setting (82.87%) and the highest of Brix (4.97). This line also had high yield (70.91 tons/ha). TN52 had the highest yield (80.69 tons/ha) among the processing tomato lines, and TN561 had the biggest fruit (90.1 g). All of F1 hybrid tomato lines had high resistant level to late blight and bacterial wilt diseases.

In the present study, the authors studied the interaction between 26 monogenic differentials carrying 26 blast resistance genes with 15 isolates of Pyricularia oryzae under field conditions and pathogenicity assays. The result in field conditions showed that area under disease progress curves (AUDPC) of monogenic lines was found to range from 0 to 142.3. Lijiangxintuanheigu (LTH) was susceptible in all of regions. The monogenic lines carrying Pik, Pik-p, Pik-h, Piz, Pi1, Pi7(t), Pik-m, Pi4(t), Pish, Pi9(t) and Pita were highly resistant to blast in all of regions. In plastic house net conditions, the percentage of virulent reactions of monogenic lines to 15 isolates was found to range from 23.1% to 84.6%. LTH was susceptible to all 15 isolates. All 26 monogenic lines were resistant to at least 3 isolates of P. oryzae, and the frequency of resistant reactions of the monogenic lines carrying Pik, Pik-p, Pik-h, Piz, Pi4(t), Pish, Pi1, Pi7(t), Pi9, Pik-m and Pita were 80.0%, 93.3%, 93.3%, 80.0%, 73.3%, 86.7%, 73.3%, 80.0%, 80.0%, 80.0% and 80.0%, respectively. These findings suggest that Pik, Pik-p, Pik-h, Piz, Pi4(t), Pish, Pi1, Pi7(t), Pi9, Pik-m and Pita may be important R genes for preventing blast disease in South Central Vietnam. Based on these data, a useful strategy for managing rice blast disease by stacking pyramiding blast R genes against pathogenic P. oryzae isolates at hotspot in South Central Coast of Vietnam was proposed.

Five lines of introduced pepper obtained from National Institute of Horticultural and Herbal Science, Korea, namely YT1, YT2, YT3, YT4, KR1, and two local varieties, namely Chia Voi and Moi, were used in this study to evaluate bio-agronomy characteristics and yield components in summer-autumn season 2014 at Thua Thien Hue, Vietnam. The experiment was laid out in a random complete block design (RCBD) with three replications. The results showed that all of the introduced pepper accessions can grow under Thua Thien Hue condition. The introduced accessions as KR1, YT2 and YT4 showed good adaptability. These pepper lines had high yield and good fruit qualities, like Chia Voi. YT4 gave high number of leaves and plant height. Accession KR1 had the highest number of fruits per plant and yield (1397.8 kg/ha). Accession YT2 had high fruit setting rate and the biggest fruit (8.08 g). YT2 and YT4 had high yield, which were equivalent to Chia Voi. These accessions need to be conducted another trials in different areas and seasons to confirm their growth ability and can be used in crop structure at Thua Hien Hue province and breeding programs.