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Production of vetiver in Indonesia is low, and its oil quality is not in line with market demand due to the low quality of plant raw materials. In vitro mutagenesis using ethyl methanesulfonate (EMS) has the potential to produce superior vetiver variants. This study aimed to determine the effect of EMS on the growth and shoot formation of in vitro vetiver plants. In vitro mutagenesis was performed by culturing in vitro shoots on MS medium containing EMS with various concentrations (0.02; 0.04; 0.06; 0.08; 0.1%) for 4 weeks. The results showed that the addition of 0.02-0.1% EMS to the medium affected on in vitro shoot growth and the ability to form new shoots. EMS increased the percentage of dead explants and decreased the average number of shoots, the number of shoots formed per explant, and the shoot fresh weight. The higher the EMS concentration in the medium, the smaller the percentage of survived explants and the lower ability to form new shoots with the average number of shoots formed less. The percentage of survived explants on the medium without the addition of EMS and on the medium with the addition of EMS with low concentrations of 0.02 and 0.04% reached 100% with an average number of shoots formed ranging from 8.5-10 shoots/explant. Meanwhile, the percentage of survived explants on medium with the addition of EMS with a high concentration of 0.08-0.1% was only 12.5-25% with an average number of shoots formed was less than 2 shoots/explant. Keywords: EMS, in vitro shoots, Vetiveria zizanioides .

The objective of this research was to evaluate the effect of gamma irradiation on shoot growth and multiplication of Patchouli ( Pogostemon cablin Benth.) Two weeks-old in vitro shoots were irradiated gamma-ray, at doses of 0, 15, 30, 45, 60, and 75 Gy. The control shoot was not irradiated. The irradiated shoots were cultured on Murashige and Skoog (MS) medium supplemented with 0.1 mg.L -1 NAA and 0.3 mg.L -1 BA and incubated in a growth room for eight weeks at a temperature of 25±2°C. The results showed that the gamma irradiation inhibited the growth and multiplication of shoots. Explants irradiated with high-dose gamma-ray (45-75 Gy) had not formed shoot in four weeks of culture, while 58.3-83.3% of the explants without irradiation or irradiated at low doses 15 and 30 Gy formed shoots. The higher irradiation doses increased percentage of browning explants and reduced the percentage of forming shoots. Within the eight weeks of culture, explant without irradiation was able to form shoots at the percentage of 100% with 24 shoots per explant, while explants irradiated at 15-45 Gy were able to grow form shoots at the percentage of 77.7-95.5%. The high doses-irradiated explants (60 and 75 Gy) were only able to form shoots less than 13-20%, with 2-3 shoots per explant. Keywords: Gamma rays (Gy), in vitro shoot, Pogostemon cablin Benth.

Flooding has been reported to cause various responses in plants ranging from wilting to death. However, there is a lack of information about wilting and dying occurrence in C. frutescens L. This study aimed to identify the influence of flooding on wilting and death in C. frutescens L. and to know the correlation between both parameters after flooding stress. Three varieties of C. frutescens L. (Cakra Hijau, Mhanu XR, and Sret) were used in this study. Plants were grown in a greenhouse and treated with periodic flooding treatments (controls, periodic 0, 1 and 2). Wilting was scored visually by a scale of 0-5 where 0 for no wilting, and 5 for plants that died. Death occurrence was observed by counting the number of the dead plant until harvest period. Mann-Whitney analysis showed a significant difference (p

Cayenne pepper is known as a sensitive plant to water stress, either drought or flooding. However, not many studies on the plant's response to the naturally occurring periodic flooding have been reported to date. This study aimed to determine the agronomic and genetic response of cayenne pepper against periodic flooding and find whether RAPD profile reflects periodic flooding endurance. Three cultivars of cayenne pepper: Cakra Hijau (CH); Mhanu XR (M); and Sret (S) were used. Plants were treated with periodic flooding P0 (one day of flooding followed by two days of drainage), P1 (2 x P0), and P2 (3 x P0), and C as control. A completely randomized design was used for the experiment, and the data obtained were analyzed statistically. Plant height and the number of fruits between the control and every flooding treated plant were significantly different, indicating that periodic flooding caused the delay of stem growth and decreased fruit number of all cultivars. The number of branches was influenced significantly by periodic flooding. In contrast, the plant survival rate showed no significant difference among all treatments. The higher the periodic flooding, the higher the risk of plant death and increased risk of production loss. Jaccard’s clustering on RAPD profiling indicated that the group was developed based on cultivar more than periodic flooding. It was concluded that CH differed from others and had better endurance against periodic flooding, made it a right candidate for a breeding program.

The purpose of this study was to determine the effect of explant types and plant growth regulators on callus induction of geranium (Pelargonium graveolens L’Her). Callus induction was carried out by culturing leaf and petiole explants from ex vitro geraniums on MS + 0.5 mg/l 2.4-D + 0.1 and 0.3 mg/l Benzyladenine (BA) or Kinetin. Each culture was carried out in 5 replications, cultures were incubated in rooms 25°C and 600 lux. The parameters days for callus induction and percentage of callus formation were observed. Geranium callus formation was influenced by types of explants and plant growth regulators. Petiole explants was able to induce callus better than leaf explants. Days for callus induction at second week and percentage of callus formation of petiole explants were 58 and 58% compared to leaf explants were only 53 and 54%. Plant Growth Regulators BA combined with 2.4-D was able to induce callus better than kinetin. The best callus formation was produced from petiole explants cultured on MS + 0.5 mg/l 2.4-D + 0.3 mg/l BA by 84%.

In soybeans, drought stress causes 50% yield losses. Breeding for drought tolerance in soybeans has been widely developed using various methods, among which is polyethylene glycol (PEG-6000) induction to simulate drought in vitro. In a previous experiment, three somaclones with different levels of tolerance were generated. The objectives of this research were to determine the RAPD patterns of those somaclones and to investigate the correlation of the RAPD patterns to the drought tolerance characteristics. The results showed eleven RAPD primers capable of amplifying the DNA genome of soybeans, among which four primers were monomorphic and seven were polymorphic. Two of the polymorphic primers, OPK7 and OPK12, are capable of differentiating medium tolerance traits from other traits. Bands that are specific for medium tolerance against drought were 450 bp and 650 bp in size, generated by the OPK7 primer, and the band of 2000 bp, generated by the OPK12 primer. However, there was no band capable of differentiating between sensitive and tolerance varieties/lines, although some changing of the DNA sequence was detected in this research. This indicates that there are other factors responsible for the expression of drought tolerance.

The objectives of this research were to identify auxin gene, AUX1, and to determine the plant auxin content and their role in conferring branching on Kenaf. PCR analysis using AUX1 primer capable to amplify the DNA of non branching (KR11) and branching kenaf mutant, resulting in 800 bp PCR product. The sequence of the PCR product showed high degree of homology with the sequence of AUX1 gene of other plants in the NCBI GenBank database, confirming kenaf possession of the gene AUX1. However, some variation on the DNA sequence was found between branching and non branching phenotype indicated allele differences of the same gene which were responsible for the variation in the type of branching. Identification of auxin content in the roots, apical shoot, and axillary branches using spectrophotometry method showed that the branching plant has higher auxin content in the apical shoot compared to the content in the branches. This indicate that AUX1 controls the formation of branches by controlling either the content of auxin in the apical shoot and branches, or the ratio of auxin content in the shoot and branches.

Proline is one of amino acid that usually accumulates inside the plant cell when facing drought stress. The accumulation of proline can protect the plant cell from damage during drought. The aim of this research was to determine proline content and yield components of local corn cultivars from Kisar Island, Maluku, Indonesia. The field trial was organized using randomized block design with three replicates. Six local corn cultivars found in Kisar Island (Deep Yellow, Early Maturing Yellow, Red Blood, Rubby Brown Cob, Waxy, and White) were used as plant materials and a recommended tolerance variety (Srikandi) was taken as reference group. Proline content was determined using ninhydrin method. Yield components variables included cob weight (at harvest, after air dry, after oven dried, at 12% of water content), cob water content at harvest, cob length, cob diameter, number of seed row per cob, number of seed per cob, and cob yield at 12% of water content. Data collected was analysed with analysis of variance followed by Duncan multiple range test at the significant level 0.05 using Statistical Analysis System/SAS software version 9.0. The result shows that highest proline content and yield components (except for cob water content) was showed by the Deep Yellow cultivar. The lowest proline content was showed by Rubby Brown Cob cultivar. The lowest corn yield components was showed by Red Blood local cultivar. Deep Yellow cultivar can be proposed as superior drought tolerance variety, and can be recommended for further wide cultivation in Maluku province.