Abstract:
Grass pea (Lathyrus sativus) have many valuable characteristics and its cultivation requires the least
crop management but, its full potential has not been utilized because of the presence of the neurotoxic
amino acid β-N-oxalyl-L-αβ -diaminopropionic acid (ODAP) which causes neurolathyrism in human
beings on prolonged consumption. Conventional breeding practices and other approaches explored to
date have not been successful in considerably reducing the toxin. Therefore, integration of in vitro
techniques such as somatic hybridization, somaclonal variation and genetic transformation can
contribute significantly to meet the challenge. Hence, the present study was carried out to evaluate the
in vitro regeneration capacity of some grass pea genotypes and eventually to optimize protocol for in
vitro propagation of the crop as in vitro regeneration capacity is prerequisite to alleviate the ODAP
problem through in vitro techniques. In this study, three experiments were conducted: cotyledonary
node shoot initiation of four genotypes (IVATLS-LS -B2, IVATLS-LS –B1, IVAT-LS- 690, and IVATLS-655),on MS media withthree concentrations of BAP (1, 2 and 3mg/l) + 0.1mg/lNAA were tested
whereas for in vitroshoot multiplication, the combination effects of four levels of BAP (1, 2, 3, and 4
mg/l) and Kn(0,1,2 and 3mg/l) were used for the selected genotype (IVAT-LS-690 and for in vitro
rooting, IBA and IAA alone with four concentrations each (0.1, 0.25, 0.5 and 1.0mg/l) were evaluated
on half strength MS medium. Among the four genotypes tested for shoot initiation, shoot nitiation
percentage was the highest (100%) for IVAT-LS-690,on MS medium augmented with 2 mg/l BAP
+0.1mg/lNAA. With regards to the in vitro shoot multiplication of IVAT-LS-690, 3mg/l BAP+1mg/l Kn
gave maximum shoot number per explant (11.5), and longest shoot (5.03cm). For in vitro rooting of
this genotype, best result for percent of rooted shoot (86.66%), high number of roots per shoot (6) and
longest root (4.9cm) were obtained from half MS medium supplemented with 0.5mg/l IBA and these
rooted plantlets were acclimatized and established in soil. From this study it could be inferred that
both genotype and BAP levels play crucial role for shoot regeneration capacity and the optimum
hormonal combination for grass pea is genotype specific. MS media supplemented with BAP and
Kn(3mg/l BAP+1mg/l) for shoot multiplication and half -MS medium supplemented with 0.5g/l IBA
for rooting could be used for in vitro propagation of IVAT-LS-690 genotype. Therefore, this work
could be used as a baseline for further studies on in vitro technique of grass pea aiming at meeting the
challenge of ODAP
