Efficient and reproducible somatic embryogenesis and micro propagation in tomato via novel structures -Rhizoid Tubers

Abstract

10An improved and highly reproducible system for invitro regeneration via somatic 11 embryogenesis (S.E), applicable to several varieties of tomato (cv. Riogrande, cv. Roma 12 grande, hybrid 17905 and model cv. M82) has been developed. First, we developed a 13 conventional indirect organogenesis for all four varieties used in this study. The 14 cotyledons and hypocotyls of 6-day-old tomato were used as explants (1-2 cm) for callus 15 induction (CI) on different callus induction media (CIM) T 0 -T 12 (6-Benzylaminopurine 16 BAP, NAA Naphthalene acetic acid, ZEA Zeatin, IAA Indole-3-acetic acid, KIN 17 Kinetin). Maximum CI response was seen on CIMT 6 (0.5 mg/L NAA, 1 mg/L BAP) and 18 CIMT 7 (2 mg/L IAA, 2 mg/L NAA, 2 mg/L BAP, 4mg/L KIN) in a period of 2 weeks 19 for commercial varieties cvs. Riogrande and Roma. However, cv. M82 responded after 4 20 weeks to a combination of treatments [CIMT 6 (0.5 mg/L NAA + 1 mg/L BAP) and 21 CIMT 8 (2 mg/L IAA + 2 mg/L NAA + 2 mg/L BAP + 4 mg/L ZEA)] for the production 22 of calli. The Riogrande, being the most responsive commercial variety, was selected for 23 invitro morphogenesis via S.E. During S.E. young cotyledons and hypocotyls explants 24 were tested on media with different ranges of pH (3 -7) supplemented with 0.5 and 2 25 mg/L NAA. Resultantly, numerous rhizoids (~38) were produced from each explant at 2 26 pH4 in dark conditions. Further incubation of each rhizoid under light conditions led to 27 the formation of a novel structure -rhizoid tubers (RTBs) on MS media supplemented 28 with 5 mg/L TDZ/BAP at pH4. We observed that only lower pH-induced rhizoids and 29 RTBs regenerated into multiple individual shoots on media at normal pH (5.8). The RTBs 30 led to a complete plantlets regeneration in 45 days compared to the conventional invitro 31 morphogenesis (60 days).32

LYCOPENE CONTENT IN SEVERAL AGES OF TOMATO CALLUS (Lycopersiconesculentum Mill. cv. Rampai)

“…Surface sterilization of seed explants requires chemicals toxic to microorganisms, but not toxic to seeds, so these chemicals are often required at low concentrations (Bharti et al, 2018). The sterilization method is also one of the things that affect the success rate of seed germination (Saeed et al, 2019). Thus, the sterilization method needs to be optimized because it varies quite a lot depending on the variety of seeds and the conditions of the explants.…”

Callus Induction, Regeneration and Establishment of Rice Plant from Mature Embryo

“…The production and quality of embryogenic calli has been shown to be influenced by interactions between genotypes and culture conditions [17]. Several studies have reported that plant growth regulator 2, 4-D is the most suitable auxin for callus induction in rice tissue culture [18,19,20,21]. In this study, the effectiveness of different concentrations of 2, 4-D alone was evaluated for callus induction from dehusked seeds of six rice genotypes.…”