Masdiar Bustamam

Developing Rice with High Yield under Phosphorus Deficiency: Pup1 Sequence to Application

The major quantitative trait locus (QTL) Phosphorus uptake1 (Pup1) confers tolerance of phosphorus deficiency in soil and is currently one of the most promising QTLs for the development of tolerant rice (Oryza sativa) varieties. To facilitate targeted introgression of Pup1 into intolerant varieties, the gene models predicted in the Pup1 region in the donor variety Kasalath were used to develop gene-based molecular markers that are evenly distributed over the fine-mapped 278-kb QTL region. To validate the gene models and optimize the markers, gene expression analyses and partial allelic sequencing were conducted. The markers were tested in more than 80 diverse rice accessions revealing three main groups with different Pup1 allele constitution. Accessions with tolerant (group I) and intolerant (group III) Pup1 alleles were distinguished from genotypes with Kasalath alleles at some of the analyzed loci (partial Pup1; group II). A germplasm survey additionally confirmed earlier data showing that Pup1 is largely absent from irrigated rice varieties but conserved in varieties and breeding lines adapted to drought-prone environments. A core set of Pup1 markers has been defined, and sequence polymorphisms suitable for single-nucleotide polymorphism marker development for high-throughput genotyping were identified. Following a marker-assisted backcrossing approach, Pup1 was introgressed into two irrigated rice varieties and three Indonesian upland varieties. First phenotypic evaluations of the introgression lines suggest that Pup1 is effective in different genetic backgrounds and environments and that it has the potential to significantly enhance grain yield under field conditions.

Mapping quantitative trait loci conferring blast resistance in upland indica rice (Oryza sativa L.)

A genetic analysis of blast resistance in upland rice variety is very crucial. In this study, we performed a linkage mapping of quantitative trait loci (QTLs) for blast resistance using an advanced backcross population from a cross between Way Rarem (susceptible indica variety) and Oryzica Llanos 5 (durable resistant indica variety). A transgressive segregation was observed in the advanced backcross population of Way Rarem//Oryzica Llanos 5. A total of 16 QTLs have been identified along chromosomes 1, 3, 5, 6, 7, 8, 9, and 11 against eight blast pathogen isolates. Each QTL accounted from 11.31 to 45.11% of the variation in blast resistance. Most QTLs showed race specificity, demonstrating the small effect of such QTLs. Unexpectedly, several superior blast resistance alleles were contributed by Way Rarem, the susceptible-recurrent parent. Among eight candidate defense response genes detected in several loci, a single gene (oxalate oxidase) present on chromosome 3 was found to be associated with blast resistance in upland indica rice. Ultimately, these advanced backcross lines with resistance to blast tagged by markers might be useful for pyramiding blast resistance alleles in upland rice.

Respon Genotipe Padi Gogo terhadap Defisiensi P

Research was carried out in a screen house at Indonesian Center for Rice Research and in the rice field at Pati, Central Java, during the Wet Season 2009. Design of each experiment was factorial with three replications. The first factor consisted of four varieties, namely IR74, Ciherang, Hipa 4, and Muncul. The second factor consisted of three insecticides, namely imidackloprid, BPMC, and deltamethrin. Results of the screen house trial showed that varieties IR74 and Ciherang were able to reduce nymph population of brown planthopper (BPH) biotype 4 generation 1 (G1) from Pati, Central Java, by 52.9% and 19.1%, respectively. Variety IR74 reduced nymph population of BPH biotype 4 generation 2 (G2) by 39.8%. The Insecticides Effectiveness (IE) values of imidakloprid, BPMC, and deltamethrin treatments at dosages 0.5 kg/ha; 1.5 l/ha, dan 0.25 l/ha, respectively, against BPH Biotype 4 Generation 1 (G1) and Generation 2 (G2) were less than 50%. Insecticides imidacloprid, BPMC, and deltamethrin each was not effective against the BPH. On the other hand, IE of imidacloprid, BPMC, and deltamethrin at the recommended dosages to BPH biotype 1 G1 in he screenhouse were 99.8%; 50.6% and 24.7%, respectively. Results of the field trial in Pati showed that varieties IR74, Ciherang, Hipa 4, and Muncul prior to 65 days after transplanting (DAT) did not reduce the BPH populations, but at 75 DAT, varieties IR74 and Ciherang reduced the BPH populations up to 52.3% and 66.1%, respectively. Decrease in the BPH population by imidacloprid ranged from 20.1-52.4% and by BPMC from 9.2-26.4%. Yield of IR74 which resistant variety to BPH Biotype 3 was significantly higher than that of Ciherang with a yield different of 3263 kg/ha.Insufficient P is a limiting factor for rice production. Tolerant varieties to deficiency P are very important to solve the problem. The objective of the experiment was to evaluate rice genotypes to P deficiency and its interaction to Al toxicity. The experiment was conducted at the green house of ICABIOGRAD (Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development) in WS 2006, using Yoshida solution. Molecular analysis was conducted in 2010 to observe the effectiveness of gene Pup1 segment in upland rice varieties to be compared with Kasalath tolerance variety from India. Plastic box of 10 ltr, containing solution as media was used in the experiment. The treatments were arranged in a split-split plot design with three replications. Treatments were two levels of Aluminum (0 and 45 ppm Al) as a main plot, and 4 levels application of P fertilizer (0, 0.5, 5.0, and 10 ppm P) as sub plots, and sixteen upland rice genotypes as sub-sub plots. Results showed that there were interactions between P, Al treatments and genotypes to characters which were observed. Application of P up to 10 ppm P increased plant height, number of tillers, shoot dry weight, and root dry weight significantly, but not for root length. The effects of aluminum were decreasing in plant height, shoot and root dry weight and root length significantly, but not for number of tillers. Evaluation of tiller number for P deficiency treatment showed three cultivars were tolerant to P deficiency, namely: Way Rarem, Limboto and Sentani, and five genotypes were moderately tolerant: Way Rarem, Jatiluhur, Sentani, K36-5-1-1, Limboto, dan NIL-C443. Genotypes indicated tolerant to both Al toxicity and P deficiency, were Way Rarem, Jatiluhur, Sentani, K36-5-1-1, Limboto, dan NIL-C443. There were no correlation between rice tolerance to P deficiency with rice tolerance to aluminum toxicity. Molecular analysis using Pup1 specifik primers showed fully Pup1 segment on NIL-C443, K36-5-1-1, Jatiluhur, Limboto, Silugonggo, Way Rarem and those genotypes showed tolerance or moderately a tolerant to P deficiency, except for Silugonggo.The number of improved red rice varieties (red color caryopsis) is still limited, namely Bahbutong and Aek Sibundong. Red rice is useful as functional food due to its antocyanin content which have a potential function as antioxidant. The research was aimed to study the effect of processing (milling and cooking) on the thiamin (vitamin B1), riboflavin (vitamin B2), niacin (vitamin B3), and pyridoxin (vitamin B6) content of new varieties, local red vareties and advanced lines of red rice. The materials used in the experiment were two red rice advanced lines, local red rice (Jembar Beureum and Jatiluwih), red rice improved variety Aek Sibundong, and white rice variety Ciherang. Results showed that milling and cooking processes reduce thiamin, riboflavin, niacin , and pyridoxin contents on advanced improved red lines, red improved variety, local red varieties and Ciherang white improved variety. Jembar Beureum milled and cooked rice had the highest thiamin and niacin content. Jatiluwih milled and cooked rice had the highest riboflavin and pyridoxin content. Local red rice had higher vitamin B content than improved red advanced lines, Aek Sibundong and Ciherang white rice. Local red rice varieties may be used as parent material on the breeding program to develop red rice improved varieties with higher vitamin B content.Research on the effect of packaging material for aromatic rice quality and its life storage was carried out. The aromatic rice varieties i.e Pandanwangi, Sintanur and Mentikwangi (each 750 kg) were dried in box dryer at 45oC for 12 hours. The dried paddy was milled at commercial milling to produce milled rice. The milled rice then were packed in high density polypropylene (HDPP), super bag and plastic sac. Factorial treatments were arranged in a completely randomized design, replicated thrice. The first factor was aromatic rice varieties (Sintanur, Mentikwangi and Pandanwangi) and the second factor was packaging material (superbag, high density polypropylene (HDPP) and plastic sac). Each treatment consisted of 5-7 kg of milled rice, kept in the room condition for six months. The physical, chemical characteristic, organoleptic test, and flavor composition were observed at the beginning, the middle and the end of storage. The result showed that physical quality of rice decreased parallel with the duration of storage. The whiteness, transparency and milling degree of rice kernel decreased as the period of storage increased. The infestation of insect in storage was found at 60 days after storing (at the second month) and tended to decrease parallel with insect life cycle. The used of plastic sac as packaging was invested by insect more than those of super bag and high density polypropylene. Therefore plastic sac was not recommended for packaging of aromatic rice at room condition. Organoleptic test indicated that cooked quality of aromatic rice decreased parallel with storing time. Based on colour, aroma, taste and texture, aromatic rice should be consumed within 90 days. After 90 days, the colour, aroma, taste and texture of the cooked rice was less preferred by panelis. The uses of plastic sac to pack aromatic rice produced cooked rice less preferable than those of super bag and high density polypropylene plastic.