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Domestic production of chilli in Malaysia is insufficient which accounted for 52% self-sufficiency level. Poor performance of local varieties under high temperatures above 42°C is one of the major ...

Rice blast disease, caused by Magnaporthe oryzae, is the most important and most devastating rice disease globally. For genetic analysis of resistance to rice blast, the present study used a BC2F1 population developed through marker-assisted backcrossing from a cross between blast susceptible MR263 and blast resistant Pongsu Seribu 1 (PS1). We selected out of 450 markers, 65 polymorphic simple sequence repeat markers, including the Pi gene-based markers, and identified 16 markers associated with blast resistance that showed heterozygous bands in the BC2F1 population. Of the 16 polymorphic markers, only eight (RM5961, RM263, RM163, RM224, RM262, RM168, RM229 and RM169) showed a good fit to the expected segregation genotypic ratio (1:1) for the single dominance gene model (df = 1.0, P

Lodging has limited yield and potential of increasing yield in rice. Lodging could be minimized by increasing the mechanical or physical strength of the rice culm. Silicon (Si) is associated with sturdiness and rigidity. Therefore, the objectives of this experiment were to evaluate the effects and optimum rate of Si application to improve yield, growth, and lodging resistance of MR219, a popular rice variety in Malaysia. Si, in the form of fertilizer, was applied at the onset of reproductive stage as topdressing. All Si-treated plants showed an increase in number of tillers, number of spikelets per panicle, number of effective tillers, percentage of filled spikelets, and weight per panicle in Si-treated plants as compared to control. Lodging resistance was higher in plants treated with Si as shown by bending parameters. Si-treated plants showed significant increase in flag leaf area, chlorophyll content, and Si content.

Studying the strategies of improving abiotic stress tolerance is quite imperative and research under this field will increase our understanding of response mechanisms to abiotic stress such as heat. The Hsp70 is an essential regulator of protein having the tendency to maintain internal cell stability like proper folding protein and breakdown of unfolded proteins. Hsp70 holds together protein substrates to help in movement, regulation, and prevent aggregation under physical and or chemical pressure. However, this review reports the molecular mechanism of heat shock protein 70 kDa (Hsp70) action and its structural and functional analysis, research progress on the interaction of Hsp70 with other proteins and their interaction mechanisms as well as the involvement of Hsp70 in abiotic stress responses as an adaptive defense mechanism.

A cross was made between MR219 (high yielding but submergence intolerant) and Swarna-Sub1 (submergence tolerant) to produce submergence-tolerant rice variety using the marker-assisted backcrossing (MABC) method to protect the farmers of low-lying land from flash floods during rain. Knowledge of yield and yield contributing factors plays a vital role in the selection process of a variety. This experim ent was designed to determine the genetic diversity among recently produced different lines of BC2F3 population and also to compare all the lines with MR219 to find the best one. Agronomical, yield and yield contributing data were taken, while genotypic and phenotypic coefficients, variance components and heritability were estimated. Introgression of the target gene, Sub1, was done using tightly linked marker, and also background recovery was measured using simple sequence repeat (SSR) markers in different generations. The observed recurrent parent genome (RPG) recovery of BC2F2 generation was 95.37%, which indicates high-level similarity between the recurrent parent (MR219) and the resulting lines. Thirty newly developed lines of BC2F3 population, resulting backcross of MR219 and Swarna-Sub1, were planted with four replications following randomised complete block design (RCBD). Newly developed lines were grouped into four clusters based on traits with UPGMA dendrogram and cluster analysis to select the 10 best plants. This study will help the future researchers to select the best plants of a breeding programme after introgression of a gene considering phenotype performances to develop new varieties.

The growth of the greenhouse chili industry is rapidly increasing in the world including Malaysia. Currently, compost is the most popular growing media. Four fertilizer formulations commonly used by farmers (Local), including the recommended Cooper, Bennoit and Cooper Modified formulation, were evaluated in combination with two volumes (400 and 750 L) for enhancement fruit yield of chili in soilless culture. The results indicate that, the day of blooming and fruiting was reduced by 91% and 50% in media containing coconut dust (CD) + empty fruit bunch (EFB) compared with CD alone. Yield with CD+EFB was increased 36% compared with CD while volume of water shows insignificant difference. Interestingly, Cooper, Local and Cooper Modified formulation enhanced 32, 28 and 19% of yield, respectively. As conclusion, combination of CD+EFB with Cooper, Local and Cooper Modified were more efficient in yield production compared with CD alone for future research.

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 F1 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.

Five levels of water stress cycle (control flooded, control saturated, 5, 10, and 15 days of irrigation interval) and three potassium fertilization levels [80 kg, 120 kg, and kg 160 dipotassium oxide (K2O) ha−1] were exposed to investigate the influence of potassium fertilizer for minimizing water stress effect and maximizing productivity of rice. Different phyto-physiological parameters as well as uptake of major nutrient elements [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe)] were examined. It was observed that rice yield, harvest index, and other physiological parameters reduces with increasing duration of water stress while application of additional potassium fertilizer has progressive impact on those parameters. From our observation, 10 days of watering cycle with potassium fertilization at 120 kg K2O ha−1 produces highest grain yield and harvest index. Uptake of major nutrient elements was also enhanced by potassium fertilizer. Therefore, it can be stated that...

The physical and chemical parameters were monitored for seven weeks during Trichoderma/Aspergillus inoculated rice straw composting at various pH levels. Three treatments (A, B, and C) were inoculated with lignocellulolytic microbial consortium (Aspergillus niger, F44 and Trichoderma viride, F26) and three were un-inoculated (D, E, and F). pH of the starting materials was amended to 5.75 (A and D), 6.75 (B and E), and 7.75 (C and F) with either acetic acid or sodium hydroxide. Three typical phases of temperature were observed both in inoculated and un-inoculated treatments during composting: mesophilic phase, thermophilic phase, and followed by cooling and maturation phase. The bioconversion were maximum in Trichoderma/Aspergillus inoculated treatments within 14–21 days as indicated by the profiles of electrical conductivity, bulk density, total carbon and nitrogen, and germination index. After day 21, the germination index of Trichoderma/Aspergillus inoculated treatment (B) without any pH amendme...

The eating and cooking qualities of rice are heavily emphasized in breeding programs because they determine market values and they are the appealing attributes sought by consumers. Conventional breeding has developed traditional varieties with improved eating and cooking qualities. Recently, intensive genetic studies have pinpointed the genes that control eating and cooking quality traits. Advances in genetic studies have developed molecular techniques, thereby allowing marker-assisted breeding (MAB) for improved eating and cooking qualities in rice. MAB has gained the attention of rice breeders for the advantages it can offer that conventional breeding cannot. There have been successful cases of using MAB to improve the eating and cooking qualities in rice over the years. Nevertheless, MAB should be applied cautiously given the intensive effort needed for genotyping. Perspectives from conventional breeding to marker-assisted breeding will be discussed in this review for the advancement of the eating and cooking qualities of fragrance, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT) in rice. These four parameters are associated with eating and cooking qualities in rice. The genetic basis of these four parameters is also included in this review. MAB is another approach to rice variety improvement and development in addition to being an alternative to genetic engineering. The MAB approach shortens the varietal development time, and is therefore able to deliver improved rice varieties to farmers within a shorter period of time.

Microbial fortified organic amendment in chili cultivation may affect plant development and disease suppression. Microbial infused rice straw compost, commercial rice straw compost, and fungicide Benomyl for chili (Capsicum annum L.) cultivation and control of Sclerotium foot rot were studied under glass house condition. Chili seed cv. Kulai were sown in the Sclerotium rolfsii infested and non-infested soil. After two weeks, five healthy seedlings were transplanted into planting bags. Growth performance and development of disease symptoms associated with S. rolfsii foot rot infection were assessed. Applying microbial infused rice straw compost increased seed germination and plant growth, and suppressed development of foot rot compared to using commercial rice straw compost and the Benomyl. A higher disease reduction (84.6%) occurred with 15 Mg · ha−1 microbial infused rice straw compost (62.7%), followed by Benomyl (53.8%), and 15 Mg · ha−1 commercial rice straw compost (46.2%). Application of mi...

One of the most valuable traits in high-quality rice is aroma or fragrance, which is important for consumer preference and global trade. Aromatic rice is unique and recognized as a badge of honor and an asset in many countries. Among more than 100 volatile components, 2-acetyl-1-pyrroline (2AP) is believed to be the main aromatic compound in rice. The principal gene contributing to 2AP is badh2, which was mapped on chromosome 8 by map-based cloning. A deletion in this gene truncates and makes non-functional the BADH2 protein. Thus, the mutant badh2 transcript leads to 2AP accumulation in aromatic rice. The discovery of the gene has led to the clarification of the biochemistry, molecular genetics and evolution of fragrant rice. The breeding of fragrant rice is now faster because of marker assisted selection (MAS), which is based on recognized genes. For a more extensive elucidation of all effective and fundamental factors contributing to rice fragrance, it is essential to further explore target quantitativ...

The present study was conducted at the Composting Unit, Universiti Putra Malaysia to determine the physico-chemical changes, microbial dynamics, and enzyme activities during microbial composting of rice straw at different pH conditions. Different treatments comprising of composting substrates (A), substrates with microbial consortium (B), substrates, microbial consortium, and acetic acid (C), substrates, microbial consortium, and sodium hydroxide (D) were used to enhance the composting process of rice straw. In inoculated treatments, the temperature increased rapidly to higher than 50°C by day 5 and remained above 40°C up to day 17, while in the control the temperature increased slowly and peaked (46°C) at day 9 and remained above 40°C until day 23. The results showed that biodegradation was at its maximum in microbial-infused treatments within 14–21 days as indicated by profiles of pH, reduction of C/N ratio, lignocellulolytic (lignin peroxidase, endoglucanase, and exoglucanase) enzyme activitie...