Tissue Culture Laboratory Research Articles

Induction of Callus of Two Cultivars from Rice Seed Embryos by the Effect of Abiotic Factors for Drought Tolerance ex Vivo

The experiment was conducted at the Plant Tissue Culture Laboratory, College of Agricultural Engineering Sciences, University of Baghdad, during the period 2021-2023, with the aim of inducing Callus from embryos of two rice cultivars: black rice and Amber 33, to enhance drought tolerance in vitro. The Completely Randomized Design (CRD) was applied for experimental arrangements. Different concentrations of 2,4-Dichlorophenoxyacetic acid (2,4-D) (0, 1.5, 3, 4.5 mg L-1) were used to stimulate Callus, along with UV radiation of type UV-C with a wavelength (<280 nanometers), It does not affect the environment because it is absorbed by the atmosphere’s oxygen and ozone, for various durations of 15, 30, 45, and 60 minutes. A control treatment was also used for comparison. The experimental stress conditions were induced using different concentrations (0, 1.5, 3, 4.5, and 6%) of polyethylene glycol (PEG). The fresh and dry weights of Callus were measured for all treatments, in addition to assessing the drought tolerance index. The results showed significant differences for most of the studied traits. The highest fresh and dry weight of Callus was achieved at a concentration of 3 mg L-1 of 2,4-D, at 258.9 mg and 26.06 mg, respectively. The control treatment with UV-C radiation outperformed with the highest fresh and dry weight of Callus, reaching 356.8 mg and 37.81 mg, respectively, compared to other irradiation doses. The control treatment with other PEG concentrations yielded the highest fresh and dry weight of Callus for the cultivars treated with UV-C radiation, reaching 356.4 mg and 38.81 mg, respectively. The drought tolerance index in terms of dry weight, the treatment with 1.5% PEG yielded the highest rate at 0.73 mg, while the treatment with 6% PEG resulted in the lowest rate at 0.21 mg. additionally; the black rice cultivar treated with UV-C radiation outperformed the Amber 33 rice cultivar in terms of both fresh and dry weights of Callus.

Role of Plant Growth Regulators on Multiplication of Stevia rebaudiana Inside Manufactured Temporary Immersion Bioreactor and Induction of Callus from Explant

The experiment was conducted at Plant Tissue Culture Laboratory - Department of Horticulture and landscape gardening, from October 2021 to January 2023. micropropagation experiments were conducted using five levels of Kinetin 0.0, 1.0, 2.0, 3.0, and 4.0 mg L. Callogenesis experiments were performed using four levels of Naphthalenacetic Acid 0.0, 1.0, 2.0, and 3.0 mg L. A temporary immersion bioreactor was used with a 10-minute immersion period every 4 hours, and two levels of Kinetin and two levels of benzyl adenine were added to the Murashige and Skoog medium as a comparative treatment. The results showed that the concentration of 1.0 mg L had a significant effect on the number of shoot and leaves, and the comparative treatment showed a significant effect on shoots height. The results of multiplication in the manufactured bioreactor showed a significant effect on shoots height, reaching 4.8 cm, and the concentration of 1.0 mg L benzyl adenine showed a significant effect on the number of shoots, with 3.2 shoot per plant, and the number of leaves for the same treatment was 17.1 leaves per shoot.

Role of Sucrose and Benzyladenine in Stevioside Content of Stevia Rebaudiana Leaves in Temporary Immersion Bioreactor

The experiment was carried out in the plant tissue culture laboratory of the Department of Horticulture and landscape gardening from October 2021 to January 2023. micropropagation experiments were conducted using concentrations of BA 0.0, 0.5, 1.0, 1.5 and 2.0 mg L, and an experiment with the addition of three levels of sugar (30, 60 and 90 g L) with two levels of BA (0.0 and 1.0 mg L). The results of the micropropagation showed that the concentration 1.0 mg L giving the highest average number of shoots of 3.5 shoots per plant, and giving the highest average number of leaves of 16.8 leaves of the shoot and the superiority of the comparison treatment in giving the highest average height of shoots amounting to 4.5 cm. The results showed that concentration 60 interacted with BA giving the highest average height of the shoots amounting to 4.3 plant shoots. and the concentration 60 interacted with the comparison treatment in giving the highest average shoot height of 4.4 cm and the concentration 90 interacted with BA in giving the highest average number of leaves amounting to 14.1 leaf shoot. The results indicated that the concentration 90 sucrose interacted with 1.0 mg L BA in giving the highest content of stevioside amounting 171.02

In Vitro Propagation of Pomegranate (Punica granatum L.)

This study was conducted in the plant cell and tissue culture laboratory of the Department of Horticulture and Landscaping / College of Agriculture, University of Kirkuk – Iraq. To study in vitro propagation of pomegranate by adding (0.0, 0.5, 1.0, 1.5, and 2.0) mg .L−16-benzyladenine (BA) and (0.0, 2.0, 4.0, 6.0, and 8.0) mg .L−1Kinetin (Kin) on Initiation state. The results showed that the highest rate number of branches is 1.20 branches. Vegetative part −1 for the medium supplemented with 0.5 mg .L−1 BA, the highest average for the longest length branch was 2.00 cm, the highest average for the number of leaves was 6.40. Vegetative part −1 when cultivated in the medium supplemented with 1.5 mg.L−1 BA. Whereas, when treated with Kin, the highest rate of the number of branches was recorded, 0.70 branches, vegetative part−1. The length of the most extended branch was 1.00 cm, at a concentration of 4 mg .L−1. The highest average number of leaves was 3.40 leaves, vegetative part-1, when cultured with the medium supplied with 8 mg. L −1.

Isolasi dan Identifikasi Mikroba Penyebab Kontaminasi dari Udara di Laboratorium Kultur Jaringan Tumbuhan UIN-SU Medan

Plant tissue culture laboratory is a technique for growing cells, tissues or slices of plant organs which are often called explants in the laboratory in an artificial media containing aseptic (sterile) nutrients to become a whole plant. This research aims to know the isolation and identification of contaminating microbes in the plant tissue culture laboratory and to know the types of contaminating microbes in the plant tissue culture laboratory. This research was conducted from december 2022 to january 2023 at the Wahdatul Ulum plant tissue culture laboratory, uinsu medan with 5 main sampling points.the sampling point consists of an incubation room, planting room and practicum space which is divided into 3 collection points. Staining tests and biochemical tests are conducted at the USU faculty of mathematics and natural sciences microbiology laboratory. The results of the study found 23 bacterial isolates that contamined the wahdatul ulum plant tissue culture laboratory at UINSU Medan consisting of the genera bacillus, lactobacillus, streptobasil, aeromonas, pseudomonas, serratia, bacteroides and acinetobacter while the contaminating fungi were Mucor sp. Contamination occurs due to mobility and activity in the laboratory room.

Pengaruh Wadah dan Lama Penyimpanan Terhadap Viabilitas dan Vigor Benih Hotong (Setaria italica (L) Beauv)

The aim of this research is that hotong seeds can be preserved for a long time so that they can be stored and used for cultivation in the next planting season. This research was conducted at the Tissue Culture Laboratory and Plant Physiology Laboratory at the Faculty of Agriculture, Pattimura University, Ambon, which took place from February to May 2021. Completely randomized design method, two factors, three replications. The first factor was seeds in open space (A0), seeds in aluminum foil (A1), seeds in glass bottles (A2), seeds in clear plastic (A3), and seeds in white cloth (A4). Another factor is the retention time (B) which consists of three stages, namely: 1 month (B1), 2 months (B2), and 3 months (B3) storage. BNJ test and Anova analysis at 95% confidence level. The treatment to maintain the quality of the hotong seeds was the 3rd month storage aluminum foil (A3B3) which could maintain a moisture content of 9.4%, PTM 80.67%, and the growth rate and vigor of hotong seeds at 81%, and the worst treatment in maintaining the quality of viability and vigor. seeds were calico fabric treated in the 3rd month of storage (A1B3).

Tissue Propagation of Marjoram Plant (in vitro)

The experiment was conducted in the plant tissue culture laboratory of the Department of Horticulture and Landscape Engineering, College of Agriculture, University of Kirkuk for the season 2022. to study the propagation of the marjoram plant tissue from tips of branches outside the body. plant parts were sterilized for a period of 10-15 min, water was used to remove dust, and they were sterilized inside the cultivation table in Naocl sodium hypochlorite solution (commercial minor solution) at a concentration of 6% for 8 minutes in order to remove suspended microscopic parts. plant parts were washed 3 times each for 5 minutes. plant parts were cut, and tips of branches were taken, with (1) cm. with kinetin at, 2, 4, 6, 8) mg. L-1. plants were vaccinated at a temperature of 25 + 2 m 0 with an intensity of illumination was 3000 lux, with a light sequence of 16 hours, followed by 8 hours of darkness, for 4 weeks of cultivation. data were taken for the experiment (length of the longest branch) (number of branches) (number of leaves). after replanting the tips of the branches for another 4 weeks of the multiplication process, data were taken at (length of the longest branch cm) number of leaves/plant part). tips of branches. Regarding the root experience, data were taken (percentage of rooting %) (average number of roots/vegetative part) (average root length/cm) (branch length/cm) (number of leaves/vegetative part) full and half concentration of salt from the same soil were added to cultivated on a medium with different concentrations of IBA.

Induksi Tunas Beberapa Varietas Nilam (Pogostemon cablin Benth.) dan Konsentrasi BAP Secara In Vitro Shoot Induction of Several Varieties of Patchouli (Pogostemon cablin Benth.) and Concentration of BAP In Vitro

Conventional propagation of patchouli plants has not met the demand for superior seeds. Propagation of superior seeds in a relatively short time can be done using in vitro culture techniques. This research aims to determine the induction of patchouli shoots of Tapaktuan, Lhokseumawe and Sidikalang varieties with Benzyl Amino Purine (BAP) concentrations in vitro. This research was carried out at the Plant Tissue Culture Laboratory, Faculty of Agriculture, Syiah Kuala University. This research used a Randomized Block Design with a 3x4 factorial pattern consisting of 2 factors. The first factor was patchouli variety which consisted of 3 levels, namely: Tapaktuan, Lhokseumawe, and Sidikalang. The second factor was BAP concentration which consisted of 4 levels, namely: 0 (control), 0.5, 1, and 1.5 mg L-1. The results showed that the percentage of live patchouli explants was 100% in all treatments. The time and percentage of shoot emergence tended to be faster in the Lhokseumawe + BAP 0.5 mgL-1, namely 17.5 days after planting (DAP) and 100%. The number of patchouli explant shoots tended to be high in the Sidikalang + BAP 0.5 mgL-1, namely 12 shoots. The number of patchouli explant leaves tended to be high in the Lhokseumawe + BAP 1 mgL-1, namely 13 sheets. Patchouli explants tended to be taller in the Sidikalang + control, namely 8 cm. The percentage of callus formation tends to be high in the varieties Tapaktuan + BAP 1 mgL-1, Sidikalang + BAP 0.5 mgL-1, Sidikalang + BAP 1 mgL-1, Tapaktuan + BAP 1.5 mgL-1, Sidikalang + BAP 1.5 mgL-1 and Sidikalang + control were above 50% at 4 WAP. The number of patchouli explant roots tended to be high in the Tapaktuan + control, namely 16.50 roots. &#x0D; &#x0D; Keywords: Aceh Patchouli, BAP, Cytokinin, Explant, Patchouli Shoots

Effect of sucrose in strawberry micro-propagation using platform bioreactor under temporary immersion system

The study was carried out in the tissue culture laboratories at the College of Agriculture / University of Kufa during the period from April 2020 to October 2021 where the aim was to assess the efficiency of micropropagation of strawberries by adding different concentrations of sucrose (30, 40 and 50 g.L-1 ) to the nutrient medium in combination with different cultivation systems: Semi-solid media system and temporary immersion system using the Plantform bioreactor. The results showed that both the highest concentration of sucrose and the culture system under the medium immersion, individually or combined, were the highest and significantly effective in increasing the rate of number of shoots (runners), leaf content of macro and minor elements, total soluble sugars, plant pigments and fresh weight of biomass. Generally, the highest values were recorded in the shoots grown in liquid media supplied with 50 g.L-1 sucrose under temporary immersion in the PlantForm bioreactor compared with those grown in semi-solid media. Keywords: Fragaria × ananassa, micro-propagation, plant nutrition, tissue culture, PlantForm bioreactor

Respon Pertumbuhan Tanaman Porang (Amorphophallus muelleri Blume.) Dengan Penambahan NAA (Naphthalene Acetic Acid) dan BAP (6-Benzyl Amino Purine) Pada Perbanyakan Secara In Vitro

Porang is one of the export crops that are much hunted in several countries. The increasing number of needs has resulted in limited porang seeds so that there is a need for propagation of porang plants with good quality, one of which is by propagation through tissue culture or in vitro. In order to propagate porang plants in vitro, this research tries to discover the ideal concentration of NAA and BAP. From August to December 2022, this study was conducted in the Plant Tissue Culture Laboratory of Jember State Polytechnic. The experiment employed a parametric statistical design with 2 treatments: 0.5 mg/L NAA + 1.5 mg/L BAP (P1) and 0.5 mg/L + 2.5 mg/L BAP (P2), with each treatment being repeated 10 times. According to the findings, the parameters of callus emergence time (46 HST) and callus diameter (1.51 cm) were best achieved by administering NAA and BAP at a dosage of 0.5 mg/L NAA + 2.5 mg/L BAP. According to the study aims, the optimal concentration for explant growth and development is believed to be 0.5 mg/l NAA + 2.5 mg/l BAP.

Pengaruh Teknik Hardening dan Konsentrasi Paclobutrazol terhadap Pertumbuhan Planlet Krisan (Chrysanthemum sp.) pada Tahap Aklimatisasi

The increasing interest and demand for chrysanthemum plants affect their economic value, which causes the quality of chrysanthemum plants to be demanded from all sides. One of the efforts to meet the needs of chrysanthemum plants in a short time is tissue culture. However, the acclimatization stage becomes a critical stage that threatens the presentation of chrysanthemum plantlets. This study aimed to determine the interaction between hardening techniques and paclobutrazol concentration on the growth of chrysanthemum plantlets at the acclimatization stage. This research was conducted in the Green House of the Tissue Culture Laboratory of Jember Polytechnic from November 2022 to January 2023. This study used a factorial complete randomized design (CRD) repeated 4 times. The first factor is the hardening technique consisting of 2 levels, H0 (no hardening), and H1 (hardening). The second factor is paclobutrazol concentration which consists of 3 levels, P1 (10 ppm), P2 (15 ppm), and P3 (20 ppm). Observational data were statistically analyzed using ANOVA, if the results showed significantly different effects then continued with the BNT test at the 5% level. The results showed that the hardening treatment had a significantly different effect on leaf color with a score of 3.5. Treatment with a paclobutrazol concentration of 20 ppm had a significantly different effect on increasing plant height by 2.71 cm and increasing the number of leaves by 1.38. This suggests that paclobutrazol and hardening treatment are needed at the acclimatization stage of chrysanthemums.

Pertumbuhan Tanaman Anggrek Cattleya (Cattleya eximia) secara In-Vitro pada Media MS dengan Subtitusi NAA dan BAP

Orchid plants are one of good prospects commodities for the floriculture business because they have high aesthetic value. Cattleya orchid has distinctive characteristics with large, beautiful, brightly colored and fragrant flowers. In vitro propagation is one way to meet the increasing demand for orchids. In vitro culture techniques require a lot of culture media to multiply plants in large quantities, so an alternative is needed to increase the effectiveness of using media such as the addition of plant growth regulators. Therefore, research was carried out on the growth of in vitro cattleya orchids on MS media with NAA and BAP substitutions. This study aimed to determine the effect of adding NAA and BAP to MS media on the growth of in vitro cattleya orchid explants. This research was conducted from June to September 2022 at the Jember State Polytechnic Tissue Culture Laboratory. This study used completely randomized design factorial. The first factor was the NAA concentration consisted of 3 levels, namely 0, 1 and 2 ppm. The second factor was the BAP concentration consisted of 3 levels, namely 0, 2 and 4 ppm. Observational variables included plant height, the number of shoots, leaves and roots. Data were analyzed using analysis of variance (ANOVA) and Duncan's Multiple Range Test (DMRT) at 5% level. Giving NAA 2 ppm + BAP 2 ppm was the best treatment for the number of leaves while giving NAA 2 ppm resulted in the best root growth.

Optimalisasi Metode Sterilisasi Eskplan Kelapa Sawit (Elaeis guineensis Jacq) Secara In Vitro

Oil palm commodity (Elaeis guineensis Jacq) is one of the largest vegetable oil producing plants besides soybean seeds, sunflower seeds and coconut oil. Due to the good prospects, the farmers want to increase the productivity of oil palm plantations. However, the provision of superior and quality seeds is a problem. One good alternative to overcome this problem is the need for vegetative propagation through tissue culture techniques. This study aims to determine the effectiveness of the sterilization technique on leaf explants of the oil palm (Elaeis guineensis Jacq) in vitro which was carried out from February to March 2023 at the Tissue Culture Laboratory of the Jember State Polytechnic. The experimental design used for this study was a Non-Factorial Completely Randomized Design (CRD) consisting of 4 treatments. Each treatment consisted of 10 replications, each replication consisting of 1 bottle containing 1 explant. The treatments used were treatment A (70% alcohol; 0.1% HgCl2, 2 g/l ascorbic acid; 2% NaOCl + 0.1 g/l fungicide), B treatment (10% NaOCl; 80% alcohol; HgCl2 0.1%) treatment C HgCl2) 0.03%; NaOCl 2%; Alcohol 50%) and treatment D (70% alcohol; bayclin 10%; bayclin 20%). From the results of research conducted that treatment D (70% alcohol; bayclin 10%; bayclin 20%) showed the best results to sterilization method of oil palm explants

Growth And Results of Some Microgreens of Order Caryophyllales on Different Plant Media

The research was conducted at the Tissue Culture Laboratory, Faculty of Agriculture, Asahan University, from March 2022 to April 2023. The aim of this study was to determine the growth and yield of several microgreens of the order Ceryophyllales on different planting media. The design used was a factorial Completely Randomized Design (CRD), with 1 treatment factor: the first factor was: Growing Media (M) (M) consisted of M1 = rockwool, M2 = cocopeat, M3 = vermiculite. The observed variables consisted of: percentage of live seeds, number of seed germinations, plant height, number of leaves, fresh weight.The results showed that the treatment of several microgreens of the order (O) caryophyllales where the red spinach (O2) treatment gave the highest percentage of survival could have a real effect on the percentage of live seeds 0.82%, the number of seed germinations 13.89%, plant height 1.48% , number of leaves 1.51%, and the treatment of basil plants was not significantly different at 0.56% fresh weight. The treatment of different planting media (M) where the treatment of vermiculite growing media gave the highest percentage of survival could have a significant effect on the percentage of live seeds 0.79%, the number of seed germinations 11.22%, plant height 1.44%, number of leaves 1.45% , and the treatment of cocopeat plant media was not significantly different at 0.52% fresh weight. The interaction of several microgreens of the order Caryophyllales and different growing media had no significant effect on the percentage of live seeds, the number of seed germinations, plant height, number of leaves, fresh weight.

Drought stress induced by polyethylene glycol (PEG) in local maize at the early seedling stage

Drought stress adversely impacts growth, crop production, reproductive organ development, and yield characteristics in maize. As a drought-sensitive crop, maize (Zea mays L.) shows considerable varietal differences. A study was conducted at the Tissue Culture Laboratory, Department of Biology, Faculty of Mathematics and Natural Sciences, University of North Sumatra, Medan, Indonesia in order to identify drought-tolerant maize varieties. During germination and early seedling growth, 16 local accessions were evaluated for drought tolerance. Based on local climate and soil conditions, these specific accessions were chosen. The varieties were tested against five levels of drought stress imposed by Polyethylene glycol 6000 (PEG-6000) at 10, 20, 30, 40, and 50%. An experiment with three replications was conducted using a completely randomized design. In the study, local maize accessions (BI3, SB5, DS2, and MN3) and the hybrid variety (H) showed the capability of tolerating drought stress. Generally, germination time, germination percent and vigor index, root and shoot length, shoot ratio, and fresh and dry weight were decreased by increasing PEG concentrations (up to 50%). According to ANOVA results, shoot water content was not significantly affected by the PEG, nor was the interaction between the PEG and the accessions. The root water content, however, was significantly affected by PEG, and the interaction between PEG and accessions. Although interactions between accessions with low PEG concentrations improved germination characteristics, the root histology of the accessions varied. According to drought tolerance indexes, five maize accessions are drought-tolerant, including H (0.683), SB5 (0.617), DS2 (0.565), MN3 (0.512), and BI3 (0.504). The drought-tolerant varieties are recommended in regions with low rainfall or low water sources since they are less water-intensive and produce higher yields.

The Effect of PVP (Polivinil Pirolidon) and BAP (6-benzylamino purine) on Shoots Induction of Teak Plus Perhutani (Tectona grandis)

The goal of this study is to see how BAP and PVP concentrations affect in vitro teak shoot induction. The research was carried out at Diponegoro University’s Tissue Culture Laboratory, Faculty of Animal Husbandry and Agriculture, between April and June 2022. The research method was a 4x4 factorial design based on a completely randomized design (CRD) with three replications. The first factor was the concentration of PVP (mg.L-1): 0, 110, 220, and 330, and the second was the concentration of BAP (ppm): 0, 1.3, 2.6, and 3.9. Duncan’s Multiple Range Test (DMRT) and orthogonal polynomials were used to test the data for variance. The interaction between the 0 mg.L-1 PVP treatment and the 110, 220, and 330 mg.L-1 PVP treatments after the addition of 2.6 ppm BAP had the quickest callus emergence time, with an average of 7 days. PVP treatments of 110 mg.L-1 and 220 mg.L-1 had a significant effect on the shoot length parameter. BAP concentrations of 1.3 and 2.6 ppm were found to increase the shoot length, number of shoots, and number of leaves response parameters. The 1.3 ppm BAP treatment also reduced browning by 17% in the explants. There was no effect of PVP or BAP treatments on shoot emergence time, leaf emergence time, or the percentage of explants that formed shoots.

In vitro multiplication of “Kepok” banana (Musa acuminata x Musa balbisiana) using different concentration of BAP and NAA in MS media

This study aims to determine the effect of different composition of BAP and NAA concentration added to Murashige and Skoog (MS) basic media on the in vitro multiplication of Indonesian “Kepok” banana variety. The research was conducted at the Tissue Culture Laboratory of Bonto-Bonto Horticultural Plant Seed Center. A completely randomized design (CRD) was employed with two factors tested. Four concentrations of each BAP and NAA used were 0 ppm, 4.5 ppm, 5 ppm, and 5.5 ppm for BAP, and 0 ppm, 2 ppm, 2.5 ppm, and 3 ppm for NAA resulted in 15 composition of BAP:NAA in addition to control (without the hormones). The results show no interaction between the BAP and NAA treatments, BAP concentration of 5 ppm gave the best result on parameter time to shoots emergence (7.50 DAP). NAA concentration of 2.5 ppm gave the best results on root emergence time (8.61 DAP), time to plantlet formation (11.72 DAP), number of roots (4.81 roots) and root length (5.93 cm).

Elimination of systemic viral disease in shallot (Allium ascolonicum L) var. Bima Brebes through unconventional approach

Shallot (Allium ascolonicum L), belonging to the genus Allium are propagated vegetatively through layered bulbs. This research aimed to improve the quality of shallots by eliminating OYDV, SLDV viruses through meristematic tissue combined with the antiviral Ribavirin. The research was conducted in the IVEGRI Tissue Culture Laboratory from April to August 2018. Research materials included the infected shallot bulbs of Bima Brebes variety which were previously confirmed by DAS ELISA serology test. Meristematic tissues were cultured on MS + vitamin, MS + supplement media (sucrose 30 gL−1 + Myo inositol 100 mgL−1 + CaP 2 mgL−1 + NAA 0.15 mgL−1 + Kinetin 2 mgL−1 + GA3 0.1 mgL−1 + Gel gro 2gL−1, pH 5.7). A Completely Randomized Design with ten replications was applied for the combinations between antiviral Ribavirin concentrations i.e., 0.5,10,15, 20, 30 mgL−1, and explant size including meristematic tissue (0.5 mm) and shoot tip (2.5 mm). The results obtained through visual observation showed that the additional antiviral Ribavirin and explant size affected the percentage of growth and development of plantlets. Statistical analysis showed that there were no significant interactions between treatments. DAS Elisa serology test showed that the higher the concentration of antiviral Ribavirin the lower the percentage of virus infection.

Effect of Salinity Stress on Oxidative Stress Parameters and the Activity of Antioxidant Enzymes in Eight Durum Wheat Genotypes

This study was carried out at the Tissue Culture Laboratory, which belongs to the General Commission of Biotechnology, in order to evaluate the influence of NaCl-induced salinity stress on some oxidative parameters (MDA and H2O2) and antioxidant enzymes (CAT, APX, and SOD) in eight durum wheat genotypes (Doma1, Bouhoth11, Cham3, Bezater, Cham5, Aghamatales, Icaverve, and Icamber) in vitro, to determine the most salinity tolerant genotypes. Salinity stress was applied by adding different levels of NaCl to the growing medium (0, 50, 100, and 150 mM). The experiment was laid according to a complete randomized design (CRD) with sixteen replicates. Increasing salinity level caused an increase in both the Hydrogen peroxide (H2O2), malondialdehyde (MDA) and the activity of the investigated antioxidant enzymes (SOD، APX، CAT) compared with the control. The leaf content of both H2O2 and MDA was significantly higher in the genotype Icaverve at the salinity level of 150 mM NaCl (45.67 and 130.74 µmol g-1 fresh wt. respectively), while the activity of the enzymes SOD, APX and CAT were significantly higher in the two durum wheat genotypes, Bouhoth11 and Doma1 at the highest salinity level (150 mM NaCl). Antioxidant enzymes play a pivotal role in the defense mechanisms in the durum wheat under salinity stress conditions, and the in vitro screening tool can be effectively used to assess the genetic variability for salinity tolerance in the durum wheat crop.

Reproducibility of Somatic Embryogenesis Upon Resampling of Oil Palm Ortets

Somatic embryogenesis remains to be a key bottleneck in oil palm clonal propagation and resampling of embryogenic ortets may be one approach to alleviate this problem. Resampling, is currently practised by oil palm tissue culture laboratories to increase the production of clones from elite ortets. However, reproducibility of the embryogenesis outcome from resampling exercises has not been examined in detail. Therefore, embryogenesis reproducibility upon resampling was evaluated using the concordance correlation coefficient analysis. Sampling and resampling were conducted when ortets were seven to 19 years old. Resampling interval periods of three to eight years showed moderate concordance in embryogenesis reproducibility. An alternative analysis approach through categorising the ortets based on their embryogenesis outcomes into zero, low, medium and high embryogenesis categories indicated that 54.4 per cent of ortets reproduced their embryogenesis outcome while 35.6 per cent showed a shift by one embryogenesis category upon resampling. A resampling interval of 10 years was associated with a decline in embryogenesis outcomes. Observations from this study may help tissue culture laboratories in refining the selection of ortets for clonal propagation with the possibility of improving success rates in resampling exercises and thereby reducing operational costs. Keywords: Ortet, concordance, non-embryogenic, sampling interval.