Abstract

<p>Genetic Mapping of SSR Markers in Eight Soybean<br />Chromosomes Based on F2 Population B3462 x B3293. I<br />Made Tasma, Ahmad Warsun, Dani Satyawan, Saptowo<br />J. Pardal, and Slamet. Aluminum toxicity is one of the main<br />contrains for cultivating soybean in acid soils. Genetic<br />Hak Cipta © 2011, BB-Biogen<br />mapping of SSR markers is one step for detecting aluminumtoxicity<br />tolerant QTLs in soybean. Another step is to<br />phenotype the same population at various aluminum-toxicity<br />environments. The objectives of this study were to analyze<br />the segregation of SSR markers in progenies of an F2<br />population and map the markers in 8 soybean chromosomes.<br />The F2 population was previously developed by<br />crossing the Al-tolerant parent B3462 and the Al-sensitive<br />parent B3293. Polymorphic SSR markers in the parents were<br />used to PCR amplify DNA of the 100 F2 progenies. PCR<br />products were separated using agarose or polyacrylamide<br />gels. A Chi-Square test was done with a null hypothesis that<br />progenies segregated in a 1 : 2 : 1 ratio. Results showed that<br />125 SSR markers were polymorphics in the parents. Out of<br />125 polymorphic markers, 122 were segregated in the<br />progenies of the F2 population. Among the segregating<br />markers, 114 were segregated in a 1 : 2 : 1 ratio. Only 8<br />markers (5.6%) did not follow the 1 : 2 : 1 ratio. One hundred<br />and nineteen SSR markers were mapped in 8 soybean<br />chromosomes. These include 18 markers in chromosome<br />A2, 10 in B1, 16 (C1), 16 (F), 10 (G), 23 (J), 16 (L), and 10 (N).<br />Total genetic maps covered was 1,194.8 cM with average<br />map distances between two adjacent markers of 10.7 cM.<br />Further SSR marker enrichment is required to fill in the gaps<br />of several chromosomal regions. Genetic maps presented in<br />this study should be useful for detection of Al-toxicity<br />tolerant QTLs in soybean.</p>

The expansion of sugarcane areas as a support to national sugar production has shifted to sub-optimal dry land. In drought stress conditions, early growth of sugarcane usually can inhibite and decrease its productivity. This study aimed to test the efficacy of organic biostimulant in increasing vegetative growth of sugarcane in the dry land. Firstly, seedlings were submerged with biostimulant of Citorin-Rfor overnight. Secondly, the biostimulant application of Citorin-S was carried out by foliar sprayat age1 and4 months old trees. Humicacid 0.5% (v/v) was applied in soil before planting while the application of mycorrhiza was carried out by direct pouring on soil during planting. The results showed that the initial vegetative growth of biostimulant-treated sugarcane stem diameter and length were 23% wider and 27% higher compared to that of control, respectively. In subsequent growth cycle, all observed vegetative parameters showed higher growth value in the biostimulant-treated sugarcanes than that of the control. Plant height, stem diameter and number of tillers of biostimulant-treated sugarcanes had significantly higher values than that of the control. P3 treatment (organic biostimulant plus humic acid and mycorrhiza) was the best treatment. The height and diameter of P3 sugarcane stems were 47% wider and 59% higher, respectively, compared to that of control at 107 DAP.[Keywords: biostimulant, plant height, stem diameter, number of tillers, number of leaves] Abstrak Penambahan areal tanaman tebu untuk mendukung peningkatan produksi gula nasional telah bergeser ke areal sub-optimal lahan kering. Pada kondisi cekaman kekeringan, pertumbuhan awal tebu biasanya terhambat dan dapat menurunkan produktivitas saat panen. Penelitian ini bertujuan menguji efikasi biostimulan organik untukmeningkatkan pertumbuhan vegetatif tanaman tebu pada fase awal di lahan kering. Perlakuan biostimulan Citorin-R diaplikasikan pada benih dengan cara perendaman semalam. Perlakuan kedua, biostimulan Citorin-S disemprotkanpada saat tanaman tebu berumur 1 dan 4 bulan secara foliar spray. Aplikasi asam humat 0,5 % (v/v) di tanah dilakukan sebelum tanam, sedangkan aplikasi mikoriza dilakukan dengan pemberian langsung pada tanah saat penanaman bagal tebu. Hasil penelitian menunjukkan bahwa nilai pertumbuhan vegetatif awal tanaman tebu perlakuan memiliki diameter batang sekitar 23% dan tinggi tanaman 27% lebih tinggi daripada tebu kontrol. Pada pertumbuhan selanjutnya, semua parameter vegetatif yang diamati menunjukkan nilai pertumbuhan yang lebih tinggi pada tanaman tebu perlakuan daripada kontrol. Tinggi tanaman, diameter batang dan jumlah anakan secara statistik berbeda nyata lebih tinggi pada tanaman tebu perlakuan daripada kontrol. Perlakuan P3 (biostimulan organik plus asam humat dan mikoriza) adalah perlakuan terbaik. Tinggi dan diameter batang tanaman tebu P3 masing-masing 47% dan 59% lebih besar daripada batang tanaman kontrol pada 107 hari setelah tanam (HST).  [Kata kunci :biostimulan, tinggi tanaman, diameter batang, jumlah anakan, jumlah daun]

Apex Culture of Sugarcane Varieties PS864 and PS881 for the Provision of Superior Seed. Deden Sukmadjaja, Yati Supriati, and Saptowo J. Pardal. In vitro culture techniques have become alternative to help overcome the problems those are often encountered in the provision of seeds through conventional means. Micropropagation through apex culture in sugarcane has several advantages, such as the produced plants have higher genetic stability, high multiplication rate, and more healthy seeds (especially virus-free)., The aims of the the research were to produce seeds of two varieties of sugarcane, namely PS864 and PS881, through apex culture. Laboratory-scale research was conducted at the Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development (ICABIOGRAD), Bogor, while sowing seeds nursery was done in the Experimental Station of Gowa, South Sulawesi Assessment Institute for Agricultural Technology. The experiments consisted of initiation and regeneration of apexes, shoots multiplication, rooting induction, and acclimatization of plantlets. Research results showed the initiation and regeneration of PS864 and PS881 through apex culture could be done on MS basic medium containing 0.5 mg/l BAP. Shoot proliferation of both varieties increased in the second subculture. Addition of 1 mg/l BAP into medium in the second subculture resulted in higher average number of shoots than that of 5 mg/l BAP, both for PS864 and PS881. Addition of 1 mg/l and 5 mg/l kinetin showed no significant differences for shoot numbers compared to that of PS864 in medium containing 1 mg/l BAP. The average number of PS881 shoots in multiplication media containing 5 mg/l kinetin was higher than that of 1 mg/l kinetin. Increased concentrations of NAA and IBA from 0.1 mg/l to 0.5 mg/l in the MS medium were correlated to the increased number of roots in PS864 shoots. Meanwhile, only increased concentration of NAA that affected rooting percentage of PS881. Acclimatization showed the percentage of the plantlets grown in polybags was higher than that directly grown in planting bed. The primary seeds (G 0 ) produced in these experiments were ready to be reproduced again to obtain further stages.Keywords: Sugarcane (Saccharum spp.), apex culture, PS864, PS881.Hak Cipta © 2014, BB Biogen ABSTRAK Kultur Apeks untuk Penyediaan Bibit Unggul TebuVarietas PS864 dan PS881. Deden Sukmadjaja, Yati Supriati, dan Saptowo J. Pardal. Teknik kultur in vitro telah menjadi alternatif untuk membantu mengatasi masalah yang sering dihadapi dalam penyediaan bibit melalui cara konvensional. Metode perbanyakan melalui kultur meristem apeks pada tanaman tebu mempunyai beberapa keuntungan, antara lain stabilitas genetik tanaman yang dihasilkan lebih stabil, laju multiplikasi yang tinggi, dan dapat menghasilkan bibit yang sehat bebas penyakit, terutama virus. Penelitian bertujuan untuk memproduksi bibit dua varietas tebu PS864 dan PS881 melalui kultur apeks untuk dikembangkan di sentra-sentra pengembangan tebu di Sulawesi Selatan. Pen...

Some acid soil is potential for the agricultural development. Constraints for soybean production in the acid soils are Aluminum toxicity and macro nutrient deficiencies. Breeding for soybean varieties tolerant to acid soil is needed. This could be made through genetic engineering, by inserting acid tolerance genes into a soybean genome. Thirty one soybean lines (T0) had been obtained by insertion of Al tolerance genes (MaMt2) through an Agrobacterium mediated transformation, which nine of them contained MaMt2 gene based on PCR test. Further evaluation of those lines was carried out in the Biosafety Containment, where four T1 soybean lines were carrying MaMt2 gene, namely line GM2, GM5, GM10 and GM14. The study was aimed to evaluate the degree of tolerance of T2 generation of GM2, GM5, GM10 and GM14 lines to Al toxicity. Results showed that T2 line were able to grow in hygromicin media, indicating that those T2 lines were containing hygromicin resistant gene (hptII). Phenotypic analysis of T2 lines in four acid soil media treatments indicated that all lines could survive and grow on acid soil without liming and adding compost. GM2 line grew best on the acid medium than did other lines.