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Effect of soaking duration in 2.5% sodium hypochlorite for disinfestation of various pecan cultivar explants. Means of the columns followed by the same letter are not significantly different according to Duncan's multiple range test (P ≤ .05).
Source publication
Pecan, [Carya illinoinensis (Wangenheim) C. Koch] is a nut crop of growing worldwide interest and importance. In this research, a micropropagation protocol was developed during 2015–2016 using five pecan cultivars (‘GraTex’, ‘Wichita’, ‘Choctaw’, ‘10 J’ and ‘GraKing’). In the establishment phase, nodal segments of mature pecan trees were collected...
Contexts in source publication
Context 1
... soaking treatment of 4-5 minute duration in 2.5% sodium hypochlorite was effective for superficial disinfection of nodal pecan explants (Figure 7), confirming the results of previous studies (Corte-Olivares et al., 1990;Renukdas et al., 2010). In contrast, Haroon (2010) used 15% commercial bleach (NaOCl, 3.0% v/v) solution containing Tween 20 (0.1% v/v) for about 10-20 minutes for surface sterilization of pecan explants. ...
Citations
... Coincidentally, similar results were reported in some Juglandaceaous species. Renukdas et al. (2010) and Vahdati et al. (2020) induced the maximum adventitious shoots in two pecan cultivars, 'Desirable' and 'Cape Fear', by addition of 6.0 mg·L − 1 and 10.0 mg·L − 1 6-BA, respectively. Recently, Das et al. (2020) also obtained 100% induction rate and 6.2 adventitious shoots in Alpinia calcarata with the addition of 5.0 mg·L − 1 6-BA. ...
... However, for main economic tree species in Juglandaceae, high rooting rates (> 80%) have been reported at high concentrations of IBA (≥ 5.0 mg/L). For instance, both 83% and 76% rooting rate were attained at 5.0 mg/L IBA in C. illinoinensis and Juglans nigra, respectively (Gray et al. 1991;Vahdati et al. 2020). Even, Renukdas et al. (2010) reported that 80% root induction in C. illinoinensis happened at 10.0 mg/L IBA, which is similar to our results in C. paliurus. ...
As an endemic medicinal woody plant in China, Cyclocarya paliurus (Batal.) Iljinskajais is being extensively planted for leaf-use. Operational system of tissue culture mainly depends on tender explants only being attained in short spring. The aims of this study were to determine the additions of plant growth regulators matching to seasonal explants for inducing adventitious shoots in C. paliurus. Explants collected at three stages (March-May, stage I; June-August stageII; September-November, stage III) were cultured in MS (Murashige and Skoog medium), supplemented with gradient concentrations of 6-benzylademine (6-BA) (2.0–12.0 mg·L− 1) for shoot induction. The relationships of phytohomones between endogenesis in explants and exogenous addition in the medium were also analyzed by using artificial neural networks (ANN) for the optimal concentration of 6-BA. The optimal adventitious shoot induction happened on MS medium supplemented 6-BA with concentrations of 4.0 mg·L− 1, 6.0 mg·L− 1 and 12.0 mg·L− 1 for explants at stage I, II and III, and their induction ratios reached 92.9%, 96.67% and 82.33%, respectively. A model constructed by ANN based on a set of validation data, displayed good agreement with observed results. Also, the combination addition (0.5 mg·L− 1 6-BA + 1.5 mg·L− 1 IBA + 0.03 mg·L− 1 TIBA) to MS for shoot multiplication attained 3.20 of multiplication coefficient. Although rooting induction achieved to 66.67% when supplemented 11.0 mg·L− 1 IBA (3-indolebutyric acid) to WPM (woody plant medium), no plantlets survived after acclimatization. Therefore, more efforts should be done to build a feasible tissue culture system in C. paliurus.
... The traditional method of grafted pecan seedlings comprises two phases, i. e., sexual propagation (by seeds), which is used for producing rootstocks, and asexual propagation, which consists in grafting the crown cultivar (Poletto et al., 2015;Casales et al., 2018;Zhu et al., 2020). However, rootstocks derived from pecan seeds not only exhibit differences in plant growth and performance but also require a lengthy period to grow and end the seedling production process (Warren, 2015;VahdatI et al., 2020;Hilgert et al., 2020). ...
Pecan farming is a long-term investment which needs quality seedlings to establish an orchard. Pecan rootstocksmust have a vigorous radicular system to form quality seedlings. Liquid humus, which acts as an agent thatpromotes their growth and development, is a bioinput that is specially used in organic production systems.This study aimed at evaluating effects of different frequencies of liquid humus application on pecan rootstockgrowth and development in an organic system. Liquid humus at 30% was applied every 7, 14, 21 and 28 days.The control treatment consisted of water application. The experiment was carried out with ‘Barton’ rootstocksin a greenhouse at the Embrapa Clima Temperado located in Pelotas, RS, Brazil. The following variables wereevaluated 280 and 480 days after transplantation: plant height; stem diameter; leaf area; fresh and dry massesof the aerial part; main and secondary root lengths; fresh and dry masses of roots; fresh and dry masses of themain root; fresh and dry masses of secondary roots; and the Dickson Quality Index. Liquid humus increasedsecondary root length of pecan rootstocks, mainly when it was applied every seven days. Thus, the bioinputmay be used for this purpose.
... However, for main economic tree species in Juglandaceae, high rooting rates (> 80%) have been reported at high concentrations of IBA (≥ 5.0 mg/L). For instance, both 83% and 76% rooting rate were attained at 5.0 mg/L IBA in C. illinoinensis and Juglans nigra, respectively (Gray et al., 1991;Vahdati et al., 2020). Even, Renukdas et al. (2010) reported that 80% root induction in C. illinoinensis happened at 10.0 mg/L IBA, which is similar to our results in C. paliurus. ...
As an endemic medicinal woody plant in China, Cyclocarya paliurus (Batal.) Iljinskajais is being extensively planted for leaf-use. Operational system of tissue culture mainly depends on explants from short growth season. To extend sampling season, an efficient tissue culture system for nodal stem segments across annual growth seasons has been established in C. paliurus . Explants collected at three stages (March-May, stage I; June-August stage Ⅱ; September-November, stage Ⅲ) were cultured in MS, supplemented with gradient concentrations of 6-benzylademine (BA) (2.0–12.0 mg·L − 1 ) for shoot induction. The relationships of phytohomones between endogenesis in explants and exogenous addition in medium were also analyzed by using artificial neural networks (ANN) for the optimal concentration of 6-BA addition. The optimal adventitious shoot induction happened on MS supplemented 6-BA with 4.0 mg·L − 1 for stage Ⅰ, 6.0 mg·L − 1 for stage Ⅱ, and 12.0 mg·L − 1 for stage Ⅲ; their induction ratios reached 92.9%, 96.67% and 82.33%, respectively. Regardless of growth stage, adventitious buds occurred on the 20th day when the content of ABA at the bottom versus IAA on the peak. Moreover, high ABA content in explants of C. paliurus (128.49-325.79 ng/g FW) is considered as the main inhibitor for induction. A model constructed by ANN based on a set of validation data, displayed good agreement with observed results. Also, the combination addition (0.5 mg·L − 1 6-BA + 1.5 mg·L − 1 IAB + 0.03 mg·L − 1 TIBA) to MS for shoot multiplication attained 3.20 of multiplication coefficient. Although rooting induction achieved to 66.67% when supplemented 11.0 mg·L − 1 IBA to WPM, no plantlets survived after acclimatization. We speculate that the high 6-BA content for adventitious buds induction could be responsible for lower rooting rate and transplanting failure. Therefore, more efforts should be done to build a feasible tissue culture system in C. paliurus.
... It is widely used by horticulturalists and agricultural companies to rapidly clone plants. For example, in vitro shoot multiplication from nodal explants has been evaluated for rapid propagation of walnut and pecan cultivars with desirable traits [9,10]. Switchgrass, as well as many other grasses, can produce side shoots or branches, called "tillers", from the parent shoot. ...
... Regarding the tissue culture-based vegetative propagation, earlier studies showed growth regulators, media compositions and supplements, hardening mixtures, and culture conditions were important factors influencing the efficiency of the culture system [9,10,[24][25][26][27][28][29]. These studies also reported that different cultivars responded differently to the culture treatments, indicating the optimized culture protocols were largely cultivar (or genotype) dependent. ...
Background
Switchgrass (Panicum virgatum L.) is an important bioenergy and forage crop. The outcrossing nature of switchgrass makes it infeasible to maintain a genotype through sexual propagation. Current asexual propagation protocols in switchgrass have various limitations. An easy and highly-efficient vegetative propagation method is needed to propagate large natural collections of switchgrass genotypes for genome-wide association studies (GWAS).
Results
Micropropagation by node culture was found to be a rapid method for vegetative propagation of switchgrass. Bacterial and fungal contamination during node culture is a major cause for cultural failure. Adding the biocide, Plant Preservative Mixture (PPM, 0.2%), and the fungicide, Benomyl (5 mg/l), in the incubation solution after surface sterilization and in the culture medium significantly decreased bacterial and fungal contamination. In addition, “shoot trimming” before subculture had a positive effect on shoot multiplication for most genotypes tested. Using the optimized node culture procedure, we successfully propagated 330 genotypes from a switchgrass GWAS panel in three separate experiments. Large variations in shoot induction efficiency and shoot growth were observed among genotypes. Separately, we developed an in planta node culture method by stimulating the growth of aerial axillary buds into shoots directly on the parent plants, through which rooted plants can be generated within 6 weeks. By circumventing the tissue culture step and avoiding application of exterior hormones, the in planta node culture method is labor- and cost-efficient, easy to master, and has a high success rate. Plants generated by the in planta node culture method are similar to seedlings and can be used directly for various experiments.
Conclusions
In this study, we optimized a switchgrass node culture protocol by minimizing bacterial and fungal contamination and increasing shoot multiplication. With this improved protocol, we successfully propagated three quarters of the genotypes in a diverse switchgrass GWAS panel. Furthermore, we established a novel and high-throughput in planta node culture method. Together, these methods provide better options for researchers to accelerate vegetative propagation of switchgrass.
... Although pecan seedlings can be produced from seeds, the obtained plants will differ in the orchard due to genetic variability (Vahdati et al., 2020). In addition, when propagated by this method, the species presents slow growth and a long juvenility period. ...
The objective of this work was to evaluate the effect of the collection period and of the exogenous application of indolebutyric acid (IBA) on the rooting of cuttings from adult pecan (Carya illinoinensis) plants. The experiment was carried out in a greenhouse with intermittent mist irrigation, from December 2017 to October 2018. The experimental design was completely randomized, in a 4x5 factorial arrangement, with four collection periods (spring, summer, autumn, and winter) and five concentrations of IBA (0, 2,000, 4,000, 6,000, and 8,000 mg L-1). For the cuttings collected during summer and autumn, there was a linear relationship between rooting and the increase of the IBA concentration. The best results for rooting, callus formation, mean number of roots, mean root length, and root dry and fresh mass are obtained for the cuttings collected during summer, with the application of 8,000 mg L-1 IBA on the base of each cutting, under a mist irrigation system. The rooting of cuttings from adult pecan plants with the application of IBA is possible, being an alternative propagation method for the species.
