The results of the analysis of variance are shown in Table 1.
Table 1
Analysis of variance of the effect of explants and hormones on leaves, stems and roots of maca on traits related to callus induction.
|
|
MS
|
|
S.O.V.
|
df
|
Callus induction percentage
|
Callus growth rate
|
Explant
|
2
|
0.267 *
|
0.359 ns
|
Hormone
|
6
|
0.126 *
|
0.462 ns
|
Explant× Hormone
|
12
|
0.018 *
|
0.448 ns
|
Error
|
60
|
0.019
|
0.429
|
Total
|
84
|
-
|
-
|
C.V.
|
-
|
32
|
36
|
*, ** (significant P<0.05 and P<0.01 respectively) and ns (non-significant).
|
The results of the analysis of variance showed that the effect of explants, hormones and their interactions on callus induction percentage was significant but were not significant on callus growth rate.
Pande et al. (2002) used two combinations of culture medium in Lepidium sativum Linn. propagation by callus and through nodal sections of mature plants. In the first combination, the highest regeneration frequency was obtained with the highest number of stems, which means 25 stems in each MS medium with 2.85 µM Indole 3 acetic acid and 6.4 µM kinetin. In the second combination, the regeneration rate reached 75% and 5 stems were obtained in each MS medium with 1.14 µM Indole, 3 acetic acid and 23.2 µM kinetin.
Kaur et al. (2006) in a combined report of 3.3 µM alpha naphthalene acetic acid, 0.058 µM gibberellic acid 3 and 4.9 µM isopentenyl adenine, which accelerated callus proliferation in Brassica oleracea and Brassica napus have been.
Callus induction in leaf, stem and root explants are shown in Fig. 1. The leaf explants were the most susceptible and root inappropriate explants for callus induction.
Guo et al., (2000) reported that high doses of 2, 4-D (6.22 µM) and BAP (17.7 µM) were used for callus Brassica rapa L.
A comparison of the mean interaction effects of explants in the hormone on the percentage of callus induction in the maca plant is shown in Fig. 2.
According to the comparison of the mean, the best medium for inducing callus was Hormone 2,4-D (2 µM) and Kinetin (0.5 µM), which had the highest percentage of callus induction in leaf explants (62%) and the lowest was in stem (30%) and root (27%) explants.
The comparison of the interaction effects of explants in hormones on the percentage of regeneration in the maca plant is shown in Fig. 3.
According to the comparison of the average, the best medium for regeneration was 4 µM BAP 2.5 + TDZ, in which the highest percentage of regeneration was in leaf explant (87%) and stem (69%) and the lowest in root explant was (12 %). Images of callus regeneration percentage in three-leaf, stem and root explants are shown in Fig. 4. As can be seen in the pictures, leaf explants are the most susceptible and root unsuitable explants for callus regeneration.
Memon et al. (2009) showed that for regeneration on MS medium with 9 µM Tidiazuron, 2.6 µM alpha naphthalene acetic acid and 44.1 µM silver nitrate, stem regeneration is obtained directly from the leaves of Brassica campestris ssp Chinensis.
Osuna et al. (2006)[4] developed a propagation protocol for the medicinal plant Lepidium virginicum L. Seeds were used in vitro to prepare cotyledons, hypocotyls and apical buds. The best propagation rate after 15 days of culture was in MS medium containing 0.57 µM indole 3 acetic acid and 13.94 µM kinetin from the apical buds of the explants.
In this experiment, rooting occurred only in a culture medium containing 1 µM IBA with activated charcoal (Fig. 5). For this reason, the decomposition did not take place. The rooting time was very long. It took six months from the transfer of the regenerated plants to the emergence of the roots. One month after root emergence, seedlings were transplanted into the soil. The soil used was light soil, including potting soil in addition to cocopeat, which was disinfected by autoclave. Despite all the necessary things such as moisture retention and irrigation were done for gradual adaptation, the plant was destroyed.
Lebeda et al. (2003) [26] reported that maca plant in 51 days in MS medium without NH4N03 and with 3% sucrose (w/v) and 0.7% agar (w/v) supplemented with different types of plant growth regulators were rooted. Growth regulators include one µM zeatin z1), two µM zeatin Z2), 0.3 µM Gibberellic acid 3 (Z + GA), 2 µM Benzylaminopurine and 0.3 µM Gibberellic acid 3 (BAP + GA), 2 µM were metatopulin and 0.3 µM Gibberellic acid 3 (mT + GA).