scholarly journals Changes in biochemistry and histochemical characteristics during somatic embryogenesis in Ormosia henryi Prain

2020 ◽  
Author(s):  
Gaoyin Wu ◽  
Xiaoli Wei ◽  
Xiao Wang ◽  
Xian Liang ◽  
Yi Wei

ABSTRACTMature embryos were used as an explant for embryogenic callus (EC) induction, and then EC was further developed to form somatic embryos during somatic embryogenesis (SE) of Ormosia henryi Prain; however, some mature embryos could induced non-embryogenic callus (NEC), browning callus (BC) or snowflake callus (SC). These phenomena might be related to the biochemical and histochemical differences during somatic embryo induction. The present study was conducted to analyze the biochemical events and histochemical changes at different SE stages in 0. henryi. The contents of soluble sugar, starch, soluble protein, H2O2, and endogenous hormones and the activities of polyphenoloxidase (PPO), superoxide dismutase (SOD), ascorbate peroxidase (APX), peroxidase (POD) and catalase (CAT) were measured at different SE stages, such as EC, globular embryo (GE), and cotyledon embryo (CE), and in abnormal tissue, such as NEC, BC, and SC. The results showed that the contents of soluble sugar and starch; the activities of PPO, SOD, APX and POD; and the ratios of indole-3-acetic acid/abscisic acid (IAA/ABA), IAA/gibberellins (IAA/GAs), auxin /GAs (AUX/GAs), and AUX/ABA decreased gradually at different SE stages. In contrast, the contents of soluble protein, H2O2, all endogenous hormones gradually increased. However, CAT activity and the ratios of IAA/cytokinins (IAA/CKs), AUX/CKs, ABA/CKs, and GAs/CKs first increased and then decreased. The high contents of GAs and ABA, high ratios of ABA/CKs and GAs/CKs and low ratios of IAA/ABA, IAA/GAs, AUX/GAs and AUX/ABA were responsible for the inability of the callus to form EC. The low enzyme activities, low contents of energy substances and H2O2 were related to NEC formation. The high contents of soluble sugar, H2O2, AUX, CKs and PPO activity and the low content of soluble protein were the basic causes of BC formation. The high-energy substances contents and low activities of SOD and POD facilitated SC formation. Histochemical observation showed that starch granule staining gradually lightened with SE development, but protein granules were darkly stained. Compared with EC, starch and protein granules were stained darker in SC, and lighter in NEC and BC. These results showed that energy substances were the material basis of SE, which affected enzyme activities, regulated reactive oxygen species (ROS) metabolism, and thus regulated the morphogenesis and development of somatic embryos. In addition, the contents and ratios of endogenous hormones affected the dedifferentiation, dedifferentiation and embryogenesis of somatic cells. To induce EC from mature embryos and further develop their formation into somatic embryos, it is necessary to adjust the energy supply and hormone ratio in the medium.One-sentence summarySomatic embryogenesis and abnormal callus tissues formation of Ormosia henryi Prain were associated with energy substances, reactive oxygen species, enzyme activities and endogenous hormones, as well as histochemical characteristics.

1990 ◽  
Vol 20 (11) ◽  
pp. 1759-1765 ◽  
Author(s):  
F. B. Webster ◽  
D. R. Roberts ◽  
S. M. McInnis ◽  
B. C. S. Sutton

To apply somatic embryogenesis to clonal propagation of forest species, the technique must be applicable to a broad range of genotypes and allow efficient regeneration of phenotypically normal plants. Seventy-one lines (genotypes) of embryogenic cultures from six open-pollinated families were obtained by culturing immature embryos of interior spruce. Interior spruce represents a mixture of two closely related species, Piceaglauca (Moench) Voss and Piceaengelmannii Parry, from the interior of British Columbia where they hydridize with one another. The abscisic acid dependent developmental profile (the proportion of rooty embryos, shooty embryos, precociously germinating embryos, and mature embryos over a range of abscisic acid concentrations) differed among genotypes, but in general, production of mature somatic embryos was highest at 40 and 60 μM abscisic acid. Treatment of mature embryos with a high relative humidity treatment resulted in partial drying of the embryos and upon rehydration, markedly enhanced germination of the eight genotypes tested. Within 1 week of being placed under germination conditions, somatic embryos treated with the high relative humidity treatment showed 80–100% germination for 12 of the genotypes, and most genotypes had germination rates of greater than 40%. Survival of "emblings" (germinants from somatic embryos) following transfer to soil, acclimatization, and first season's growth in the nursery was 80% or greater for most genotypes. Over 1200 emblings were tested for nursery performance, representing the first large-scale evaluation of conifer somatic embryos under exvitro conditions. Growth rates, final height, shoot and root morphology, and frost hardiness were similar for emblings and seedlings following the first growing season. These results indicate that somatic embryogenesis can be used for the production of planting stock for a range of interior spruce genotypes.


Author(s):  
Tandra Sarkar ◽  
Atheni Konar ◽  
Nirmal Chandra Sukul ◽  
Nirmal Chandra Sukul

Background Thermal stress during early imbibitional phase of germination causes disruption of redox-homeostasis by increasing accumulation of ROS Reactive Oxygen species (assessed in terms of hydrogen peroxide) and significant reduction of antioxidative defense (assessed in terms of catalase and peroxidase) in germinating tissues of cowpea (Vigna ungiculata). It also induces oxidative damage to newly assembled membrane system by aggravating membrane lipid peroxidation [measured in terms of thiobarbituric acid reactive substances (TBARS)]. Cantharis is a homeopathic remedy used for treating burn injuries in humans. The objective is to see whether potentized Cantharis could ameliorate heat stress in germinating seeds of cowpea. Methodology Seeds, imbibed in water overnight, were divided into four groups (n=50/group): Control I (Water 200c), Control II (Ethanol 200c), treated with Cantharis 200c and untreated and unstressed. Water soaked seeds were dipped in control/drug solution for 5 min and then washed. Control II and Cantharis 200c were diluted with water 1:1000 to minimize the ethanol effect. Except the fourth group, all other groups were subjected to heat stress (450C for 8 hours). All the groups were allowed to germinate for 5 days in germination chamber at 25 ± 20C. Groups 1 and 2 (Control I and II) served as systematic negative controls throughout the experiment. Ten independent replications were performed for each group in parallel. All experiments were randomized and blinded. Results The systematic negative controls (I, II) did not produce any significant effect. The results in terms of germination, growth, soluble sugar, protein, accumulation of reactive oxygen species and loss of membrane permeability clearly exhibit that Cantharis 200c could mitigate heat stress significantly (p


Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1498
Author(s):  
Chen Chen ◽  
Hong Chen ◽  
Ming Ni ◽  
Fangyuan Yu

Styrax japonicus is a small ornamental tree with medicinal values, although its flowering period is short. To date, information about the morphological and physiological characteristics of the petals during the flowering period is limited. In this study, we observed the structure of the petals at the full flowering stage with a scanning electron microscope and detected the contents of nutrients, minerals, and endogenous hormones and the activities of enzymes at different flowering stages. The results showed that the content of soluble sugar exhibited an ‘increase-decrease’ trend, whereas the contents of soluble protein, nitrogen (N), phosphorus (P), and abscisic acid (ABA) showed a ‘decrease-increase’ pattern. The content of starch descended continuously, but the contents of potassium (K), gibberellic acid (GA3), indoleacetic acid (IAA), and malondialdehyde (MDA) ascended continuously. The activities of peroxidase (POD) and superoxide dismutase (SOD) first rose and then declined during the flowering period. Higher contents of soluble sugar, N, K, and IAA promoted S. japonicus flowering; meanwhile, lower contents of starch, soluble protein, P, and GA3 in addition to the lower activity of SOD might be some of the causes of the short flowering period. This work will serve as the foundation for a scientific technique to utilize the flowers and extend the flowering period in S. japonicus.


2009 ◽  
Vol 55 (No. 2) ◽  
pp. 75-80 ◽  
Author(s):  
J. Malá ◽  
M. Cvikrová ◽  
P. Máchová ◽  
O. Martincová

Contents of free polyamines (putrescine, spermidine and spermine) were determined in different developmental stages of Norway spruce (<I>Picea abies</I> [L.] Karst.) somatic embryos by means of HPLC. Determinations were performed embryogenic tissue after 4 weeks of the growth on proliferation medium, after 2 and 5 weeks of the culturing on maturation medium, and 2 weeks after desiccation. Maturation of somatic embryos (after 5 weeks) was accompanied by increase of concentrations of putrescine (2.3 times) and spermidine (3.2 times). In comparison with above mentioned polyamines, spermine concentrations were significantly lower (4.3 times). Two weeks after desiccation, the concentrations of putrescine decreased 5.4 times and spermidine 2.2 times in comparison with mature embryos. To improve the efficiency of somatic embryogenesis of less responsive genotypes, the supplementation of growth media by polyamines is discussed.


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