مجله فنآوری زیستی در کشاورزی
سال بیستم شماره 2 (پاییز و زمستان 1400)

In order to study the genetic diversity and grouping among 20 cultivars (from two species) of Pyrus from eastern and western species in the Research Institute of Breeding and Preparation of Seedlings and Seeds of Karaj based on 12 pairs of primers were evaluated with molecular marker (SSR). The markers used produced a total of 273 bands with a size of 100 to 150bp and, on average, each primer combination produced 6.46 polymorphic bands. The average of 90.33% for polymorphism, 0.654 polymorphic information content (PIC), 0.962 Shannon information index and 2.69 marker index indicated the existence of high genetic diversity of cultivars. Cluster analysis of molecular traits based on Dice similarity coefficient divided the cultivars into four groups. Changes in Dice similarity coefficient between 0.58 and 0.95 indicated the existence of high genetic diversity among the studied cultivars. Principal component analysis showed that the first three components together accounted for 54.50% of the total genetic diversity. Based on the results of the present study, four primers BGT23b, NH030a, NB103a and NH036b can be introduced as useful and desirable primer compounds for cultivar differentiation, so that it can be concluded that this group of primers can be used in screening the population of pear cultivars.

Lallemantia iberica belongs to the family of Lamiaceae, a year-old herb that has medicinal and oil properties. For optimization of tissue culture of this plant, two experiment: callus induction and regeneration were done. In order to investigation of callus formation, a factorial experiment was conducted in a completely randomized design with three factors: explant types (hypocotyl and cotyledon), BAP growth regulator (0, 0.5, 1, 1.5 mg/l) and NAA growth regulator (0, 1, 2, 4 mg/l) with three replications. Results of analysis of variance (ANOVA) for callus formation traits showed significant differences between some of the studied factors. The results of mean comparison of interaction effects between the studied factors showed that the highest rate of callus formation (100%) in the hypocotyl explant in NAA (4 mg/l) and BAP (0 mg/l) treatment and for cotyledon explant (100%) with the combination of BAP (1.5 mg/l) and NAA (0 mg/l) were obtained. In regeneration experiment four levels of BAP (1, 2, 3, 4 mg/l) was used. The highest percentage of regeneration was obtained for hypocotyl explant (70%) in 4 mg/l BAP and for cotyledon explant the highest percentage of regeneration (26.66%) was obtained in 3 mg/l BAP treatment. Due to the importance of this plant results of tissue culture optimization, could be use for increasing secondary metabolites and genetic engineering researches.

Garlic due to its antimicrobial activity, has a high potential in controlling of compatible bacteria in gut of pest insects. Developing the use of these compounds can be effective in plant pest management. In this study, the effect of Allicin from garlic extract on reducing the population of compatible bacteria of two moths larva Plodia interpunctella and Ephesti kuehniella gut was investigated. Initially, the two pests were bred in sufficient numbers. The Larva were used to isolation of guts bacteria. The bacteria were isolated and grouped based on phenotypic characteristics and comparison of protein electrophoresis pattern. Larvae were fed with feed containing tetracycline for three days to minimize guts bacteria, than a suspension of isolated bacteria was added to the larva diet. A series of dilutions of garlic extract were prepared with ratios of 1:1, 1:2, 1:4, 1:8, 1:16, 1:32, then 50 microliters of each dilution was added to each well in the plate and the bacterial suspension added to it. The growth inhibition zone diameter was measured and the results showed that garlic extract has antimicrobial activity against all bacteria. Antimicrobial activity of garlic was dependent on concentration and the highest activity was observed in7.816 mg/ml concentration. Bacillus safensis and Bacillus zhangzhouensis showed the highest and Serratia marsecesence showed the lowest susceptibility to allicin garlic extract. The highest and lowest MIC were related to Bacillus safensis and Serratia marcescence respectively

Caladium is an attractive ornamental plant that is very popular on the ornamental plant market due to its shape, color and leaf variety. This plant is propagated by dividing the underground stem traditionally, which does not meet the needs of the market due to low speed propagation. This study was designed and conducted to propagate this ornamental plant through tissue culture. After disinfection, leaf explants were placed on MS medium with different concentration of BAP (0.5, 1, 2 and 3 mg.l-1) and NAA (0.2 and 0.5 mg.l-1). After 4 weeks, the regenerated plants were transferred to proliferation medium including MS consisting of BAP (1, 2, 3 and 4 mg.l-1) and NAA (0.01, 0.1 and 0.5 mg.l-1). After the proliferation stage, the plants were transferred to the rooting medium containing IBA (0.1, 0.5 and 1 mg.l-1). Based on the results, the highest percentage of direct regeneration was obtained from explant leaf in medium containing 2 mg.l-1 BAP and 0.2 mg.l-1 NAA. The highest number of shoot was observed in MS medium with 3 mg.l-1 BAP and 0.1 mg.l-1 NAA and the highest shoot height in 4 mg.l-1 BAP with 0.1 and 0.5 mg.l-1 NAA. The plantlets were rooted in 0.5 mg.l-1 IBA as optimal concentration. Finally, the rooted plants have been successfully adapted to the greenhouse (With an average of 25±2°C and a relative humidity of 70 to 80%).

Bentazone is a postemergence herbicide used to control weeds in bean fields. This study aimed to isolate and identify bentazone degrading bacteria in some areas of Selseleh city. According to the results of phenotypic and biochemical tests, 30 isolates of bentazone herbicide-degrading bacteria were divided into four phenotypic groups, including Bacillus, Pseudomonas, Acinetobacter, and Stenotrophomonas. Highly degrading isolates including BaBLU3 in the Bacillus group, PsBLU2 in the Pseudomonas group, StBLU5 in the Stenotrophomonas group, and AcBLU2 in the Acinetobacter group were selected, according to the results of the minimum inhibitory concentration and the minimum bactericidal concentration. The sequencing results of housekeeping gene 16S rRNA, revealed the BaBLU3, PsBLU2, StBLU5, and AcBLU2 isolates belonged to the B. altitudinis, Pseudomonas sp., Stenotrophomonas sp. and A. calcoaceticus, respectively. This study is the first report of in vitro bioassay of the Bentazone herbicide biodegradation by using the isolates of B. altitudinis, Pseudomonas sp., Sthenotrophomonas sp. and A. calcoaceticus. Due to the ability of these bacterial isolates in degrading Bentazone herbicide, their use in bioremediation research to remove the remains of this herbicide in bean fields is recommended.

Tomato spotted wilt virus disease is one of the most important tomato diseases that causes damage in the country. To identify inbred resistant lines against Tomato spotted wilt virus (TSWV) in the present study, 64 tomato genotypes including 28 tomato hybrid (F1) cultivars were initially evaluated for the presence of Sw-5b conferring resistance using a codominant SCAR (Sequence characterized amplified region) molecular marker, NCSw003. Based on the results obtained from this stage of the study, only four tomato hybrid cultivars namely Sereen, Brivio, Jam and Xaman, carried the resistance allele. Based on the results of the second stage and 240 selected F6 inbred lines with appropriate agronomical traits those were generated from four the above-mentioned heterozygous cultivars, The inbred lines generated from Sereen, Jam, Xaman and Brivio carried out 35.6, 35.1, 25.7 and 22.2 percent homozygous resistant allele specific, respectively. Furthermore, single nucleotide polymorphism in Sw-5b gene allele was investigated for F6 selected progenies of three heterozygous cultivars, Sereen, Xaman, and Brivio using high resolution melting (HRM) technique. The comparison between the results of screening by HRM and NCSw-003 codominant SCAR marker showed 86, 98.6 and 91 consistencies, respectively. Considering identical results of both markers used for each of the above cultivars, 21, 18 and 12 pure homozygous resistant lines were identified, respectively. Also, the results of the study using NCSw-003 marker alone showed that 20 pure lines obtained from Jam cultivar have dominant homozygous resistance. The identified resistance lines with homozygous resistance can be used after biological evaluation as a resistant parent in tomato breeding programs and introduction of hybrid cultivar.

Zamioculcas zamiifolia is a member of the flower family. To optimize callus production and regeneration, the leaf explants of this plant in MS culture medium with different levels of growth regulators in dark and light conditions were investigated as a factorial experiment in the form of a completely randomized design in 4 replications. In the first experiment, leaf explants were grown in MS culture medium containing 2,4-D growth regulator in two concentrations of 4 and 8 mg/L under light and dark conditions. After 45 days, plant growth indices were measured. In the second experiment to induce shoot production, after 45 days, the explants were separately transferred to two MS culture media containing growth regulators each with BA and 2IP (zero, 2 and 4 mg/L) along with NAA (zero, 0.75, 1.5 and 2.25 mg/liter) were transferred. The highest percentage of seedling production and the highest multiplication factor were obtained in the medium containing 2 mg/l 2IP along with 0.75 mg/l NAA. Also, the effect of polyethylene glycol treatment in 4 concentrations (0, 2, 4 and 6(%)) on pine zamifolia was investigated. These results showed that the maximum leaf area of 3.65 cm2 was obtained in regenerated plants in 4% PEG. Finally, after transferring the seedlings to the greenhouse in the perlite and cocopeat bed in a ratio of 1:1, the highest compatibility percentage was 95%. In total, the regulatory role of light and growth regulators in three separate steps reveals new results regarding the micropropagation of this plant.