PhD

Nilappana, golden eye grass or black musali (Curculigo orchioides Gaertn.)
of the family Amaryllidaceae is a key member of the dasapushpa and a highly
useful plant in the indigenous system of medicine. It is a small, geophilous herb,
the rhizome of which is used as a rejuvenating and aphrodisiac drug. This
important medicinal plant on the verge of extinction has to be conserved and
domesticated for which agrotechnology is to be developed to ensure adequate
availability of quality crude drug and fetch maximum returns for the farmer. More
over, large variations are observed in the quality of the crude drug available in the
market. Hence, a project entitled 'agrotechnological practices for quality crude
drug production in nilappana (Curculigo orchioides Gaertn.)' comprising of six
experiments was undertaken during 2000-'02 at AMPRS, Odakkali to study the
growth and development pattern, characterize the primary and secondary
metabolites, assess the quantity and quality variations as influenced by cultural
practices and to develop a satisfactory management practice for maximizing the
yield with good quality.
The study on developmental physiology of C. orchioides, with two biotypes
observed for 12 months, revealed that it was characterized by an active growth
phase of 7 months, after which it could be harvested for quality rhizomes. The
rhizome development is upward which has got special agronomic significance in
that it requires deep planting and regular earthing up for higher yields. The quality
parameters like sucrose, crude fat and curculigoside contents of rhizome
decreased initially probably due to their utilisation by the plant for its
,
establishment in the field. However, they increased substantially during later
stages of the crop growth with the ons~t of active physiological activity in the
plant. The two biotypes significantly differed in growth, yield and quality
parameters. Panamkuzhi biotype is a better choice for cultivation. A lot of crop
improvement efforts need to be taken up in this crop to make it more remunerative
as it is a slow growing, less competitive and poor yielding. More over, it cannot
withstand weed competition and rodent attacks. Hence, adequate control measures
are essential for successful cultivation of the crop.

The study on characterisatrion of glycosides proved that an HPLC system
comprising of C18 column with 0.01 M phosphate buffer (pH 6.0) and peaks
monitored spectrtophotometrically at 205 nm could be used for the estimation of
curculigoside content of Curculigo orchioides.
The split plot experiment with four shade levels (0, 25, 50 and 75 per
cent) as main plots and four spacings (10xlO, 20xl0, 20x20 and 30x20 cm) as
subplots showed that the dry matter production and yields in Curculigo orchioides
were the highest at 25 per cent shade and 10 x 10 cm spacing due to higher
growth characteristics such as plant height, number of leaves, canopy spread and
also a higher chlorophyll a and a+b contents and a higher harvest index. The plant
being a poor competitor, the higher plant density at 10 x 10 cm spacing coupled
with low weed infestation, contributed to the higher yields. The content of
primary metabolites and curculigoside in rhizome was higher at closer spacing.
The uptake of nutrients was higher under shaded condition and closer spacing due
to the higher plant densities and dry matter production. The partial shade also
increased the soil pH and the content of available N, K, Ca and S in the soil. It is
suitable for cultivation as intercrop in coconut and rubber plantations.
The field experiment in RBD with three levels of FYM (10, 20 and 30 t
ha-I), five proportions of FYM and fertiliser (0:100, 25:75, 50:50, 75:25 and
100:0) and a control of no FYM and fertilizer showed that increasing levels of
FYM increased the growth parameters, dry matter production and yield.
Application of 30 t FYM ha-I had greater impact on these attributes. The fresh
rhizome as well as the dry rhizome yields were the highest at 30 t FYM in 75:25
proportion of FYM and fertiliser. Application of 30 t FYM increased the glucose,
starch, curculigoside and protein contents in the rhizome. Weed competition was
much higher with increasing proportion of FYM and it was minimum when
fertiliser alone was applied. Uptake of Mg was the highest when FYM alone was
applied while S uptake increased with increasing proportion of fertiliser.
Available Mg content in soil was higher when FYM and fertiliser were applied in
combination.
The field experiment in RBD with eight nutrient sources (control, FYM 10
t ha-I, vermicompost 1.3 t ha", poultry manure 2.7 t ha-I, FYM 10 t ha-I +

Azotobacter 10 kg ha', FYM 10 t ha-I + Phosphobacter 10 kg ha-I, FYM 10 t ha-I
+ VAM 10 kg ha-I and fertiliser N, P20S, K20 @ 40:30:20 kg ha') with and
without mulch (spent lemongrass 10 t ha') showed that considering both the yield
and quality of Curculigo orchioides no mulch treatment is better than mulch
treatment. Poultry manure application recorded the highest rhizome and
curculigoside yields which indicated its superiority over other nutrient sources for
getting a higher yield with better quality. The growth, dry matter production and
yield were the highest in poultry manure treartment followed by FYM +
phosphobacter. Poultry manure applied plots recorded a higher uptake of most of
the nutrients due to the higher nutrient contribution from the manure and the
higher dry matter production. It also improved the P and Ca status of the soil.
The study on the quality variations in C. orchioides (with two biotypes
under natural habitat and cultivation and market samples from south, central,
north and High Range zones of Kerala and the south Indian states of Kerala,
Karnataka, Tamil Nadu, Andhra Pradesh and Maharashtra) showed that there was
variation in quality with biotypes and those in natural habitat was superior in
quality compared to those under cultivation. Among the market samples collected
from the various zones of Kerala, those from High Ranges were superior in most
of the quality parameters, which indicated its superiority for high quality drug
formulations. Among the southern states, Tamil Nadu samples ranked next to
High Range samples in this respect. There exists large variability in the market
samples and there is a felt-need for proper standardisation of the crude drug for
ensuring quality in the drug formulations.