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Powdery mildew (PM) is a fungus that causes disease in both the field and the greenhouse. Utilizing resistant cultivars is the most effective approach of disease management. To develop insertion-deletion (InDel) markers associated to this trait, the whole genomes of the PM resistant line M17050 (P1) and the PM-susceptible line 28-1-1 (P2) were sequenced. A total of 1 200 InDels, with an average of 100 markers per chromosome, were arbitrarily chosen from the sequencing data for experimental validation. One hundred InDel markers were ultimately selected due to their informative genetic bands. Further, an F2 segregating population of melons generated from these two parents was inoculated by the PM pathogen. Based on bulk segregant analysis (BSA) using these 100 InDel markers, the powdery mildew resistance was associated with the genomic region LVpm12.1 on the melon chromosome 12. This region overlapped the previously described quantitative trait locus (QTL)-hotspot area carrying multiple PM-resistance QTLs. Moreover, conventional QTL mapping analysis was done, which located LVpm12.1 in the region between 22.72 and 23.34 Mb, where three highly polymorphic InDel markers MInDel89, MInDel92, and MInDel93 were detected. Therefore, these markers could be used to track this resistance locus in melon while the lines carrying this locus could be employed in PM melon resistance breeding programs after validation tests [ABSTRACT FROM AUTHOR]

Background: Soybean is an excellent source of protein, also richer in oil than most legumes, making them a good source for vegetable oil and biofuels. Among various difficulties the maturity period of existing soybean varieties is the main hindrance of utilizing this for the existing cropping system. The narrow genetic base of cultivated soybean varieties and germplasm limit the scope to utilize directly in the breeding program. Methods: Mutation breeding is one of the techniques that provide large genetic diversity from a single source. To broaden the genetic diversity Binasoybean-3 and Binasoybean-4 were imposed to different doses of gamma radiation. The mutants were selected based on their agronomic performance and grouped at five different clusters at M5 generations. Maximum selection pressure was done during maturity period with protein and oil content. Result: Finally, eight mutants were selected for the advance breeding program, whereas mutants SM-03-15-5 mature within 90 days, containing 38% protein and 18.4% oil content will be considered directly for further steps of varietal release system. [ABSTRACT FROM AUTHOR]

In Malaysia, the main constraints of rice yield and productivity are infertile soils and poor management practices because these soils are characterized by low pH, low nutrient availability, low organic matter, and high exchangeable Al and Fe ions, due to high rainfall and hot temperatures. Thus, an incubation study was conducted to determine the optimum amount of calcium silicate (HmbG brand) to improve the soil pH, electrical conductivity (EC), exchangeable Al, available P, and cation exchange capacity (CEC) of a paddy soil in Sabah, Malaysia. The Kelawat series (Typic Dystrudept) soil was incubated with calcium silicate at the application rates of 0 (T1), 1 (T2), 2 (T3), and 3 t ha−1 (T4) using a Completely Randomized Design (CRD) in triplicates for 30, 60, 90, and 120 days. The calcium silicate used significantly improved soil pH because of the release of SiO44− and Ca2+ ions, which neutralized and immobilized H+ ions. Furthermore, the neutralizing effects of the amendment impeded Al hydrolysis by up to 57.4% and this resulted in an increase in the available P in the soil by 31.26% to 50.64%. The increased availability of P in the soil was also due to the high affinity of SiO44− to desorb P from soil minerals and it is believed that SiO44− can temporarily adsorb exchangeable base cations such as K+, Ca2+, Mg2+, and Na+. Moreover, applying calcium silicate at 3 t ha−1 improved soil CEC by up to 54.84% compared to that of untreated soils (T1) because of increased pH and the number of negatively charged sites. The most suitable application rate of the calcium silicate was found to be 3 t ha−1 (T4). These findings suggest that calcium silicate can improve soil productivity and agronomic efficiency in rice farming. Greenhouse and field trials are necessary to ascertain the effects of the recommended treatments of this incubation study on soil productivity, rice growth, and yield. [ABSTRACT FROM AUTHOR]

Moringa oleifera seed solution was used in this study to treat municipal wastewater that were used as the treatment in this study. There were 3 treatments used; treated wastewater, normal tape water and untreated wastewater. The wastewater were collected at main drainage at Batu 7 (5o52'57.2''N 118o02'39.7"E) and diagnosed based on the pH and EC. Data on plant height (cm), number of leaves, leaves length (cm), chlorophyll, and number of primary branches were taken every week until week 4. For root length (cm), fresh weight (g), dry weight (g) and moisture were taken after the harvesting. The data collected were analyzed by using Statistical Analysis Software (SAS) version 9.4 computer program with experimental design was Randomized Complete Block Design (RCBD). The means were separated and compared using Duncan's Multiple Range Test (DMRT) at 0.05 significant level. M. oleifera seeds solution treated irrigation exhibited positive outcomes for most of the parameters recorded, but response of different vegetables were also different on varied parameters. The increase of pH from untreated waste water (6.40) to sanitized/treated waste water (6.73) and reduction of EC from untreated waste water (367.9) to sanitized/treated waste water (359.1) is the proof of making nutrients more available for plants uptake. From the overall study it is proved that M. oleifera seeds are suitable as the replacement and an alternative besides chemical coagulant to treat wastewater which is cheaper, eco-friendly and sustainable to be used in agricultural irrigation based on all the parameters evaluated in this study. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate the best quality parental line selection of okra (Abelmoschus esculentus) varieties based on morpho-physiological and nutritional attributes. Significant variations were observed for the measured morpho-physiological and nutritional attributes among those varieties. Among the major traits; highest fresh and dry weight of fruit was recorded in variety 3 (Ok1-MKB1) and 7 (Ok7-GGS). Days to 50% flowering and days to mature fruit harvest showed that varieties 2 (Ok2-0366) and 4 (Ok4-LG) were the earliest. Variety 4 possessed the highest level of P while variety 6 (Ok6-ABM) of okra fruits contained the highest concentration of K. Zinc content was the highest in variety 4 and the lowest was in variety 1. Next, Variety 7 had the highest concentration of Mg and the lowest was in variety 6. Variety 5 (Ok5-SS103) contained the highest concentration of Fe while variety 3 had the lowest. Lastly, variety 3 possessed the highest content of Ca while the lowest was in variety 1, respectively. Pearson's correlation analysis revealed the strongest correlation (P = 0.001) in between days to 50% flowering and days to harvest, while fruit fresh weight and fruit dry weight as well. Cluster analysis grouped those 7 okra varieties into five different clusters; where V2, V3 and V6 were solely different from others, indicating the highest diversity compared to other accessions. So, for varietal improvement program, the most judicious crossing combination can be made with V2, V3 and V6 with V1 or V5 and V4 or V7, which would bring about the greater genetic diversity. [ABSTRACT FROM AUTHOR]

Micronutrient malnutrition is a major problem in developing countries affecting women, children and infants. Biofortification, improved soil health and waste management efficiencies have been used to overcome nutrient deficiencies. Application of classical breeding and selection resulted in rapid development of staple crops through breeding. The Cucurbitaceae mainly pumpkins and squashes (Cucurbita moschata Duch., Cucurbita pepo L., Cucurbita maxima Duch. ex Lam), cucumber (Cucumis sativus L.), watermelon (Citrullus lanatus L.), and melon (Cucumis melo L.) possess beneficial vitamins and minerals that can be used as nutrients for human consumption. To improve nutritional content in Cucurbitaceae, understanding the information in the genome is important for breeders to increase the level of nutrition and quality of characteristics using biotechnology approaches. Nonconventional breeding approaches can assist conventional breeding to save time, costs, and efficacy in selection. This review describes breeding strategies for necessary solutions toward development of elite varieties of Cucurbitaceae via various approaches that contain high nutrition content and improve traits and quality to fight micronutrient malnutrition. [ABSTRACT FROM AUTHOR]

Natural sources may be a method to introduce antioxidants in the human diet. Portulaca oleracea L., Peperomia pellucida L., and Trianthema portulacastrum L are underutilized leafy vegetables. The plants may be sources for total phenolic (TPC), total flavonoid (TFC), total carotenoid (TCC), and β-carotene but information is lacking. Antioxidant activity, ferric reducing antioxidant power (FRAP), and 1,1-diphenyl-2-picrylhydrazyl (DPPH), and macro- and microminerals contents were investigated in P. oleracea, P. pellucida and T. portulacastrum. Trianthema portulacastrum had the highest TPC (1.34 ± 0.13 mg∙g−1), TFC (0.58 ± 0.08 mg∙g−1), TCC (0.14 ± 0.01 mg∙g−1), and β-carotene (0.94 ± 0.18 mg∙g−1) values. The antioxidant activity and FRAP assay were highest in P. oleracea (0.91 ± 0.09 mg∙g−1); the DPPH assay for P. pellucida was highest (IC50 = 7 µg∙mL−1). The amount of K was highest in P. oleracea (55.470 ± 0.481 g∙kg−1). The amount of Mn was highest in P. pellucida (0.251 ± 0.002 g∙kg−1). The individual underutilized vegetables may be able to supply some antioxidant compounds and mineral contents for the human diet. [ABSTRACT FROM AUTHOR]

There are compelling evidences that oxidative stress plays important role in age‐related neurodegenerative diseases and natural food‐derived dietary antioxidants appear to be the first line of defence to take care of the oxidative stress. The analysis results of this study showed that Cili Burung of the hot pepper landraces contained the highest amount of TPC (1.00 mg/g DW), TFC (0.17 mg/g DW), capsaicinoids (0.05 mg/g), and the highest FRAP activity (439 mg/g DW). However, DPPH assay revealed the highest DPPH scavenging activity (IC50 = 250 μg/ml) in Halia Bara rhizome. Rhizomes of both landraces of ginger showed a significant amount of capsaicinoids. Hot pepper Cili Ungu (5.50 g/kg) and sweet pepper Cili Kulai had the highest P contents (~5.5 g/kg). Halia Bentong ginger rhizome had the highest content of K (33.84 g/kg); however, Halia Bentong ginger roots had remarkably greater contents of Ca (10.96 g/kg). Ginger rhizomes and roots had greater contents of micro minerals compared to hot and sweet chili peppers. Ginger roots contained good amounts of bioactive compounds and mineral nutrients indicating its commercial value. Practical applications: The findings of the research are truly very informative and potential for a greater health benefits of all types of health conscious generation of all ages. Depending on the greater contents of the measured bioactive compounds (total phenolics, flavonoids, capsaicinoids, and mineral nutrients) in Chili Burung from among the hot peppers and Cili Solok from among the sweet peppers and both ginger landraces may thus be suitable for commercial production and can serve as potential parents in breeding programs for enhanced phytonutrients constituents, or for use in related research. The presence of high phenolic and flavonoid contents in Chili Burung and gingers indicated their potentiality in pharmaceutical and ethnomedicinal uses. A good amount of bioactive compounds in ginger roots indicated its commercial value. And this is the first research reported on capsaicin in ginger; however, our findings do not preclude chemo‐profiling of capsaicinoids in ginger rhizomes for its inevitability. [ABSTRACT FROM AUTHOR]

The objective of the present study is to investigate the effects of temperature on the seed germination, root development and seedling growth of watermelon. Yellow flesh watermelon seeds were incubated with control (normal temperature 25°C, 20°C, 30°C, 35°C and 40°C under lab condition. This experiment was carried out with Completely Randomized Design (CRD) with five treatments and each treatment consists of five replications. The morphological and physiological parameters were measured once a week for five weeks during the germination and early seedling establishment. The results showed that seed treated under 35°C treatment produced the best results for the days require to germination, germination percentage, root development, vine and root length, leaf expansion and seedling growth of watermelon. In addition, chlorophyll content, carotenoid content, chlorophyll fluorescence, photosynthetic yield and stomatal conductance also affected positively with the temperature treatments. Fresh and dry biomass accumulation in the seedlings of watermelon was also the highest in 35°C treatment. It can be concluded that seeds incubated with 35°C during the germination increased the germination rate, root development and seedlings growth of watermelon. [ABSTRACT FROM AUTHOR]

Marker-assisted selection (MAS) is a tool that is widely applied in tomato resistance breeding. To determine the robustness of some molecular markers commonly used in MAS, extensive screening of 964 tomato lines was performed under a controlled experimental condition. Initially, the application of 36 molecular markers targeting 26 resistance genes (R genes) and 14 major diseases was evaluated. Here, we employed basic molecular biology and bioinformatics techniques for analysis where polymorphism, accuracy and clearness of amplicons constituted the selection criteria of markers. Upon initial analysis, 20 of these markers designated as efficient markers, among which 8 were considered gene-based markers and referred to as perfect markers were selected for detail evaluation. Information extrapolated from PCR result revealed 18 R genes that control 12 diseases were grouped under efficient markers. On the other hand, grouping of breeding lines based on the number of R gene harbored comprehensively revealed 62% of the lines to be void of R gene, while 38% carry different types of R genes. This provides us with an avenue to better understand new sources of resistance in the breeding lines. Conclusively, these efficient markers and their limited PCR condition can be suggested as basis of a diagnostic kit for MAS applications against 12 major tomato diseases and the identified resistant breeding lines could be conserved in order to be propagated as different sources of resistance for the development of new resistant varieties. Therefore, in areas with high vulnerability to diseases, high efficiency combination of the relevant R genes and their pyramiding into commercial tomato varieties are proposed to be implemented as a pragmatic approach. [ABSTRACT FROM AUTHOR]

Tomato yellow leaf curl virus (TYLCV) responsible for tomato yellow leaf curl disease (TYLCD) causes a substantial decrease in tomato (Solanum lycopersicum L.) yield worldwide. The use of resistant variety as a sustainable management strategy has been advocated. Tremendous progress has been made in genetically characterizing the resistance genes (R gene) in tomato. Breeding tomato for TYLCV resistance has been based mostly on Ty-3 as a race-specific resistance gene by introgression originating from wild tomato species relatives. Improvement or development of a cultivar is achievable through the use of marker-assisted selection (MAS). Therefore, precise and easy use of gene-targeted markers would be of significant importance for selection in breeding programs. The present study was undertaken to develop a new marker based on Ty-3 gene sequence that can be used for MAS in TYLCV resistant tomato breeding program. The new developed marker was named ACY. The reliability and accuracy of ACY were evaluated against those of Ty-3 linked marker P6-25 through screening of commercial resistant and susceptible tomato hybrids, and genetic segregation using F2 population derived from a commercial resistant hybrid AG208. With the use of bioinformatics and DNA sequencing analysis tools, deletion of 10 nucleotides was observed in Ty-3 gene sequence for susceptible tomato variety. ACY is a co-dominant indel-based marker that produced clear and strong polymorphic band patterns for resistant plant distinguishing it from its susceptible counterpart. The obtained result correlates with 3:1 segregation ratio of single resistant dominant gene inheritance, which depicted ACY as gene-tag functional marker. This marker is currently in use for screening 968 hybrids varieties and one thousand breeding lines of tomato varieties stocked in Jiangsu Green Port Modern Agriculture Development Company (Green Port). So far, ACY has been used to identify 56 hybrids and 51 breeding lines. These newly detected breeding lines were regarded as potential source of resistance for tomato breeding. This work exploited the sequence of Ty-3 and subsequently contributed to the development of molecular marker ACY to aid phenotypic selection. We thus recommend this marker to breeders, which is suitable for marker-assisted selection in tomato. [ABSTRACT FROM AUTHOR]

Given the increasing emphasis on sustainable agriculture, and concerns about the adverse effects of extensive use of farm chemicals, research attention is now being focused on reducing the dependence upon synthetic herbicides, and finding alternative strategies for weed management. Allelopathic properties of crop plants may allow us to use lower amounts of herbicides with benefits for the environment and human health. Considering these aspects, the present study was conducted to investigate the allelopathic effects of six selected rice varieties (WITA-3, WITA-4, WITA-12, Woo-Co, Fukuhibiki and Kalizira) collected from Bangladesh Rice Research Institute (BRRI) on seed germination and seedling growth of five weed species; Echinochloa crus-galli, Cyperus difformis, Cyperus iria, Fimbristylis milliacea and weedy rice. The aqueous extracts of all the rice cultivars caused inhibitory effects on seed germination and seedling shoot-root length of all the weed species. However, the inhibitory effects of different rice varieties varied significantly based on the differences of weed species and weedy rice found to be the least affected compared to other weeds. WITA-12 resulted about 50% germination inhibition, 25% shoot length reduction and 23% root length reduction respectively compared to control. On the basis of average percentage inhibition, rice varieties ranked in order; WITA-12>WITA- 4>Fukuhibiki>Kalizira>Woo-Co>WITA-3. Our results suggested that there is a possibility of developing a new ecological weed management strategy using rice cultivars with higher allelopathic potentials. This means breeding of rice cultivars with higher allelopathic potential may provide natural and sustainable weed management options for rice growers. [ABSTRACT FROM AUTHOR]

Occurrence of chalkiness in rice is attributed to genetic and environmental factors, especially high temperature (HT). The HT induces heat stress, which in turn compromises many grain qualities, especially transparency. Chalkiness in rice is commonly studied together with other quality traits such as amylose content, gel consistency, and protein storage. In addition to the fundamental QTLs, some other QTLs have been identified which accelerate chalkiness occurrence under HT condition. In this review, some of the relatively stable chalkiness, amylose content, and gel consistency related QTLs have been presented well. Genetically, HT effect on chalkiness is explained by the location of certain chalkiness gene in the vicinity of high-temperature-responsive genes. With regard to stable QTL distribution and availability of potential material resources, there is still feasibility to find out novel stable QTLs related to chalkiness under HT condition. A better understanding of those achievements is essential to develop new rice varieties with a reduced chalky grain percentage. Therefore, we propose the pyramiding of relatively stable and nonallelic QTLs controlling low chalkiness endosperm into adaptable rice varieties as pragmatic approach to mitigate HT effect. [ABSTRACT FROM AUTHOR]

BACKGROUND Blast caused by the fungus Magnaporthe oryzae is a significant disease threat to rice across the world and is especially prevalent in Malaysia. An elite, early-maturing, high-yielding Malaysian rice variety, MR263, is susceptible to blast and was used as the recurrent parent in this study. To improve MR263 disease resistance, the Pongsu Seribu 1 rice variety was used as donor of the blast resistance Pi-7(t), Pi-d(t)1 and Pir2-3(t) genes and qLN2 quantitative trait locus ( QTL). The objective was to introgress these blast resistance genes into the background of MR263 using marker-assisted backcrossing with both foreground and background selection. RESULTS Improved MR263-BR-3-2, MR263-BR-4-3, MR263-BR-13-1 and MR263-BR-26-4 lines carrying the Pi-7(t), Pi-d(t)1 and Pir2-3(t) genes and qLN2 QTL were developed using the simple sequence repeat ( SSR) markers RM5961 and RM263 (linked to the blast resistance genes and QTL) for foreground selection and a collection of 65 polymorphic SSR markers for background selection in backcrossed and selfed generations. A background analysis revealed that the highest rate of recurrent parent genome recovery was 96.1% in MR263-BR-4-3 and 94.3% in MR263-BR-3-2. CONCLUSION The addition of blast resistance genes can be used to improve several Malaysian rice varieties to combat this major disease. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

13 selected purslane accessions were subjected to five salinity levels 0, 8, 16, 24, and 32 dS m−1. Salinity effect was evaluated on the basis of biomass yield reduction, physiological attributes, and stem-root anatomical changes. Aggravated salinity stress caused significant (P<0.05) reduction in all measured parameters and the highest salinity showed more detrimental effect compared to control as well as lower salinity levels. The fresh and dry matter production was found to increase in Ac1, Ac9, and Ac13 from lower to higher salinity levels but others were badly affected. Considering salinity effect on purslane physiology, increase in chlorophyll content was seen in Ac2, Ac4, Ac6, and Ac8 at 16 dS m−1 salinity, whereas Ac4, Ac9, and Ac12 showed increased photosynthesis at the same salinity levels compared to control. Anatomically, stem cortical tissues of Ac5, Ac9, and Ac12 were unaffected at control and 8 dS m−1 salinity but root cortical tissues did not show any significant damage except a bit enlargement in Ac12 and Ac13. A dendrogram was constructed by UPGMA based on biomass yield and physiological traits where all 13 accessions were grouped into 5 clusters proving greater diversity among them. The 3-dimensional principal component analysis (PCA) has also confirmed the output of grouping from cluster analysis. Overall, salinity stressed among all 13 purslane accessions considering biomass production, physiological growth, and anatomical development Ac9 was the best salt-tolerant purslane accession and Ac13 was the most affected accession. [ABSTRACT FROM AUTHOR]

Herbicidal potential of aerial parts ofTinospora tuberculataon germination and seedling growth of seven test plant species, namely rice (Oryza sativaL.); two rice weeds, barnyardgrass (Echinochloa crus-galliL.) and weedy rice (O. sativaf.spontanea); and four vegetable crops, lettuce (Lactuca sativaL.), tomato (Solanum lycopersicumL.), carrot (Daucus carotaL.), and cucumber (Cucumis sativusL.) were evaluated. Six concentrations of methanol extract (3.12, 6.25, 12.5, 25, 50, and 100 g L−1) were compared with the control (distilled water). The rate of seed germination and the radicle and hypocotyl length of 7-day-old test plant seedlings were reduced as the concentration of extracts increased compared to the control. Generally, the degree of toxicity of extracts derived from the leaves was more than the extracts derived from the stem. Cluster analysis and the concentrations required for 50% inhibition (defined as EC50) of all parameters showed that radicle growth was more suppressed than germination and hypocotyl growth. Lettuce and carrot were observed as the most sensitive plants while rice showed the highest tolerance to both extracts. Moreover, the dicot target plants were affected more severely than the monocots when treated with leaf extract. The chemical composition of theT. tuberculatamethanolic extracts was analyzed by a GC–MS system. A total of 92 and 22 constituents (not previously identified) were found in the leaves and stem, respectively. The results showed that 17 of the 92 components in the leaves, as compared to 4 of 22 compounds in the stem, are known as toxic compounds. These results suggest thatT. tuberculatacontains a significant source of plant growth inhibitors with potential for the development of future natural herbicide. [ABSTRACT FROM AUTHOR]

The methanolic extracts of 13 accessions of purslane were analyzed for their total phenol content (TPC), total flavonoid contents (TFC), and total carotenoid contents (TCC) and antioxidant activity of extracts was screened using FRAP assay and DPPH radical scavenging methods. The TPC, TFC, and TCC ranged from 0.96 ± 0.04 to 9.12 ± 0.29 mg GAE/g DW, 0.13 ± 0.04 to 1.44 ± 0.08 mg RE/g DW, and 0.52 ± 0.06 to 5.64 ± 0.09 mg (β-carotene equivalent) BCE/g DW, respectively. The DPPH scavenging (IC50) activity varied between 2.52±0.03 mg/mL and 3.29±0.01 mg/mL and FRAP ranged from 7.39±0.08 to 104.2±6.34 μmol TE/gDW. Among all the measured micro- and macrominerals K content was the highest followed by N, Na, Ca, Mg, P, Fe, Zn, and Mn. The overall findings proved that ornamental purslane was richer in antioxidant properties, whereas common purslane possesses more mineral contents than ornamental ones. [ABSTRACT FROM AUTHOR]

Purslane (Portulaca oleracea L.) is an herbaceous leafy vegetable crop, comparatively more salt-tolerant than any other vegetables with high antioxidants, minerals, and vitamins. Salt-tolerant crop variety development is of importance due to inadequate cultivable land and escalating salinity together with population pressure. In this view a total of 25 purslane accessions were initially selected from 45 collected purslane accessions based on better growth performance and subjected to 5 different salinity levels, that is, 0.0, 10.0, 20.0, 30.0, and 40.0 dSm-1 NaCl. Plant height, number of leaves, number of flowers, and dry matter contents in salt treated purslane accessions were significantly reduced (P ≤ 0.05) and the enormity of reduction increased with increasing salinity stress. Based on dry matter yield reduction, among all 25 purslane accessions 2 accessions were graded as tolerant (Ac7 and Ac9), 6 accessions were moderately tolerant (Ac3, Ac5, Ac6, Ac10, Ac11, and Ac12), 5 accessions were moderately susceptible (Ac1, Ac2, Ac4, Ac8, and Ac13), and the remaining 12 accessions were susceptible to salinity stress and discarded from further study. The selected 13 purslane accessions could assist in the identification of superior genes for salt tolerance in purslane for improving its productivity and sustainable agricultural production. [ABSTRACT FROM AUTHOR]

Highlights • Salt stress affected the growth of purslane, especially for salt-sensitive genotyope. • Higher concentration of salt stress significantly increased ω-3 contents in salt-tolerant genotyope of purslane. • Salt stress significantly increased ω-3 contents of stems in purslane. • Purslane is a prospective functional vegetable and fodder in saline areas. Abstract Purslane (Portulaca oleracea) is an important salt-tolerance plant in the world. Salt stress influenced fatty acid contents and composition. In this study, two purslane genotypes, one cultivated variety (Pakistan Local, 'PL') and another wild variety (Liaoning China local 'LCL') were chosen. The effects of 100 mM and 200 mM of NaCl stress on morphological and physiological indexes along with fatty acid contents in leaves, stems and roots of two genotypes were analyzed. The results showed that NaCl stress affected the above-ground and underground growth, chlorophyll content, photochemical efficiency and osmotic potential of purslane, especially 200 mM of NaCl stress and for salt-sensitive 'LCL'. 12 types of fatty acids were identified with gas chromatography-mass spectrometry. Alpha-Linolenic acid (18:3, ω-3 fatty acid) and linoleic acid (18:2, ω-6 fatty acid) were important fatty acids in three different organs. NaCl stress significantly increased ω-3 contents at 200 mM of NaCl stress in the leaves of 'PL' and in the stems of 'LCL'. Compared with stems and roots, the ratio of ω-6/ω-3 was very low in leaves for two genotypes, especially in 'PL'. According to our results, purslane should be generalized as a prospective functional vegetable and fodder in saline areas. [ABSTRACT FROM AUTHOR]

Combining ability analysis provides useful information for the selection of parents, also information regarding the nature and magnitude of involved gene actions. Crops improvement involves strategies for enhancing yield potentiality and quality components. Targeting the improvement of respective characters in bitter gourd, combining ability and genetic parameters for 19 characters were estimated from a 6×6 full diallel analysis technique. The results revealed that the variances due to general combining ability (GCA) and specific combining ability (SCA) were highly significant for most of the important characters. It indicated the importance of both additive and non-additive gene actions. GCA variances were higher in magnitude than SCA variances for all the characters studied indicating the predominance of the additive gene effects in their inheritance. The parent P2 (BG 009) appeared as the best general combiner for earliness; P1 (BG 006) for number of fruits, average single fruit weight and fruit yield; P4 (BG 027) for node number of first female flower and days to seed fruit maturity; P3 (BG 011) for fruit length and thickness of the fruit flesh; P5 (BG 033) for 100-seed weight; and P6 for number of nodes per main vine. The SCA effect as well as reciprocal effect was also significant for most of the important characters in different crosses.

In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named 'Binasoybean-5' for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

The world's population is increasing very rapidly, reducing the cultivable land of rice, decreasing table water, emerging new diseases and pests, and the climate changes are major issues that must be addressed to researchers to develop sustainable crop varieties with resistance to biotic and abiotic stresses. However, recent scientific discoveries and advances particularly in genetics, genomics and crop physiology have opened up new opportunities to reduce the impact of these stresses which would have been difficult if not impossible as recently as the turn of the century. Marker assisted backcrossing (MABC) is one of the most promising approaches is the use of molecular markers to identify and select genes controlling resistance to those factors. Regarding this, MABC can contribute to develop resistant or high-yielding or quality rice varieties by incorporating a gene of interest into an elite variety which is already well adapted by the farmers. MABC is newly developed efficient tool by which using large population sizes (400 or more plants) for the backcross F 1 generations, it is possible to recover the recurrent parent genotype using only two or three backcrosses. So far, many high yielding, biotic and abiotic stresses tolerance, quality and fragrance rice varieties have been developed in rice growing countries through MABC within the shortest timeframe. Nowadays, MABC is being used widely in plant breeding programmes to develop new variety/lines especially in rice. This paper reviews recent literature on some examples of variety/ line development using MABC strategy.

Purslane (Portulaca oleracea L.) is an herbaceous leafy vegetable crop, comparatively more salt-tolerant than any other vegetables with high antioxidants, minerals, and vitamins. Salt-tolerant crop variety development is of importance due to inadequate cultivable land and escalating salinity together with population pressure. In this view a total of 25 purslane accessions were initially selected from 45 collected purslane accessions based on better growth performance and subjected to 5 different salinity levels, that is, 0.0, 10.0, 20.0, 30.0, and 40.0 dS m(-1) NaCl. Plant height, number of leaves, number of flowers, and dry matter contents in salt treated purslane accessions were significantly reduced (P ≤ 0.05) and the enormity of reduction increased with increasing salinity stress. Based on dry matter yield reduction, among all 25 purslane accessions 2 accessions were graded as tolerant (Ac7 and Ac9), 6 accessions were moderately tolerant (Ac3, Ac5, Ac6, Ac10, Ac11, and Ac12), 5 accessions were moderately susceptible (Ac1, Ac2, Ac4, Ac8, and Ac13), and the remaining 12 accessions were susceptible to salinity stress and discarded from further study. The selected 13 purslane accessions could assist in the identification of superior genes for salt tolerance in purslane for improving its productivity and sustainable agricultural production.