Over the last few decades, the use of molecular markers has played an increasing role in rice breeding and genetics. Of the different types of molecular markers, microsatellites have been utilized most extensively, because they can be readily amplified by PCR and the large amount of allelic variation at each locus. Microsatellites are also known as simple sequence repeats (SSR), and they are typically composed of 1–6 nucleotide repeats. These markers are abundant, distributed throughout the genome and are highly polymorphic compared with other genetic markers, as well as being species-specific and co-dominant. For these reasons, they have become increasingly important genetic markers in rice breeding programs. The evolution of new biotypes of pests and diseases as well as the pressures of climate change pose serious challenges to rice breeders, who would like to increase rice production by introducing resistance to multiple biotic and abiotic stresses. Recent advances in rice genomics have now made it possible to identify and map a number of genes through linkage to existing DNA markers. Among the more noteworthy examples of genes that have been tightly linked to molecular markers in rice are those that confer resistance or tolerance to blast. Therefore, in combination with conventional breeding approaches, marker-assisted selection (MAS) can be used to monitor the presence or lack of these genes in breeding populations. For example, marker-assisted backcross breeding has been used to integrate important genes with significant biological effects into a number of commonly grown rice varieties. The use of cost-effective, finely mapped microsatellite markers and MAS strategies should provide opportunities for breeders to develop high-yield, blast resistance rice cultivars. The aim of this review is to summarize the current knowledge concerning the linkage of microsatellite markers to rice blast resistance genes, as well as to explore the use of MAS in rice breeding programs aimed at improving blast resistance in this species. We also discuss the various advantages, disadvantages and uses of microsatellite markers relative to other molecular marker types.

Zingiber zerumbet (L.) is a traditional Malaysian folk remedy that contains several interesting bioactive compounds of pharmaceutical quality. Total flavonoids and total phenolics content from the leaf, stem, and rhizome of Z. zerumbet at 3 different growth stages (3, 6, and 9 months) were determined using spectrophotometric methods and individual flavonoid and phenolic compounds were identified using ultra-high performance liquid chromatography method. Chalcone Synthase (CHS) activity was measured using a CHS assay. Antioxidant activities were evaluated by ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. The antibacterial activity was determined against Gram-positive and Gram-negative bacteria using the disc diffusion method. Highest content of total flavonoid [29.7 mg quercetin equivalents (QE)/g dry material (DM)] and total phenolic (44.8 mg gallic acid equivalents (GAE)/g DM) were detected in the rhizome extracts of 9-month-old plants. As the plant matured from 3 to 9 months, the total flavonoid content (TFC) and total phenolic content (TPC) decreased in the leaf, but increased significantly in the rhizomes. Among the secondary metabolites identified, the most abundant, based on the concentrations, were as follows: flavonoids, catechin > quercetin > rutin > luteolin > myricetin > kaempferol; phenolic acids, gallic acid > ferulic acid > caffeic acid > cinnamic acid. Rhizome extracts from 9-month-old plants demonstrated the highest CHS activity (7.48 nkat/mg protein), followed by the 6-month-old rhizomes (5.79 nkat/mg protein) and 3-month-old leaf (4.76 nkat/mg protein). Nine-month-old rhizomes exhibited the highest DPPH activity (76.42 %), followed by the 6-month-old rhizomes (59.41 %) and 3-month-old leaves (57.82 %), with half maximal inhibitory concentration (IC₅₀) of 55.8, 86.4, and 98.5 μg/mL, respectively, compared to that of α- tocopherol (84.19 %; 44.8 μg/mL) and butylated hydroxytoluene (BHT) (70.25 %; 58.6 μg/mL). The highest FRAP activity was observed in 9-month-old rhizomes, with IC₅₀ of 62.4 μg/mL. Minimal Inhibitory Concentration (MIC) of Z. zerumbet extracts against Gram-positive and Gram-negative bacteria ranged from 30 to >100 µg/mL. Among the bacterial strains examined, Staphylococcus aureus was sensitive to the leaf extract of Z. zerumbet, with MIC of 30.0 μg/mL and other strains were sensitive to the rhizome extracts. Three- and 9-month-old plants are recommended when harvesting the leaf and rhizome of Z. zerumbet, respectively, in order to obtain effective pharmaceutical quality of the desired compounds.

Seeds of grass pea contain an unusual amino acid, ß-N-oxalyl-L-2,3-diamino propionic acid (ODAP) also referred as B-(N)-Oxalyl-amino-L-alanine (BOAA) which is responsible for an incurable paralysis of the lower limbs of men, called lathyrism. This study included thirty bold and small seeded genotypes of grass pea to ascertain the variability and the relationship existing among seed size, content of protein and ODAP in seeds. Weight of 1000-seed ranged from 40.50 to 79.23 g. The protein and ODAP content ranged from 25.05 to 33.95% and 0.32 to 2.02%, respectively. A significant positive correlation was observed between seed size and protein content (r = 0.48**) but negative association was obtained between seed size and ODAP content (r = -0.22*). There was also negative association between the content of protein and ODAP (r = -0.16). Therefore, it may be feasible to develop low neurotoxin varieties by selecting bold seed size following hybridization of bold seeded and low neurotoxin types with those having small seeds and high neurotoxin.

The experiment was carried out under sub-tropical condition (24°75´ N latitude and 90°50´ E longitude) to investigate the growth, dry mass production and its partitioning into plant parts of three lentil varieties viz. BINA masur1, BINA masur2 and BINA masur3. The leaf area and total dry mass plant⁻¹ were superior in BINA masur3 over its growth period followed by BINA masur2 with same statistical rank. In contrast, BINA masur1 performed inferiority in leaf area and total dry mass plant⁻¹. Dry mass partitioning into seed (HI) was significantly greater in BINA masur2 and BINA masur3 with being the highest in BINA masur2 but total economic yield and its related traits were greater in BINA masur3 than in BINA masur2. Results indicated that percent contribution of dry mass partitioning into different plant parts had no significant influence on seed yield but leaf and stem dry mass production had influence on seed yield in lentil. BINA masur3 produced the highest in leaf and stem dry mass and also showed the highest seed yield followed by BINA masur2. In contrast, BINA masur1 showed the lowest seed yield for contributed lower leaf dry mass.

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Laboratory and pot experiment was conducted to control root rot caused by Fusarium solani and Sclerotium rolfsii, a devastating and wide spread disease in the world. Ten bio-agents including control were tested in these experiments. Macerated extract of Fusarium solani + Trichoderma harzianum showed the best result in controlling root rot of lentil with the highest seed germination (100%), radical length (1.56 cm), seedling emergence (95.73%), root length (8.16 cm), shoot length (17.75 cm), number of branches/5 plants (15.56). The lowest root rot (25.93%) was also observed in the treatment of Fusarium solani + Trichoderma harzianum. The other four treatments, macerated extract of Sclerotium rolfsii, Fusarium solani, Trichoderma harzianum, Sclerotium rolfsii + Trichoderma harzianum showed better results over control in terms of all plant parameters. Leaves of Jarul, Mehegoni and Acacia showed poor performance compared to control in almost all parameters.