Transcript Lac hosts

Lac hosts
Mouth parts of insect
• Sucking type mouth parts
• Suck plant juices (sole mode of feeding)
• Host plants for lac cultivation are important
Hosts
•
A large variety of plants can function as lac hosts;
•
Number of host species in use are relatively small
•
Kerr (1782) gave the first zoological description of
lac insect in modern times and mentioned only four
host plants in India
Ficus religiosa – “Pipul”
Ficus indica (Ficus benghalensis)- “Bhur”
Plaso hortus malabarici- “Praso”
(Butea monosperma- Palas)
Rhamnus jujuba (Zizyphus mauritiana)- “Beyr”
• In 1958, Roonwal listed 113 hosts in India
• 14 common
• 85 occasional and rare hosts
• Around 110 lac hosts have been recorded
from Southern China, viz., Yunnan and Tibet
State
Hosts
Bihar
Ber (Zizyphus mauritiana), kusum (Schleichera oleosa) and
Palas (Butea monosperma)
Madhya Pradesh
Ghont (Zizyphus xylopyra), kusum and palas
West Bengal
Ber, palas, kusum and species of genus Ficus
Assam
Arhar (Cajanus cajan) and species of Leea and Grewia
Jammu & Kashmir
Khair (Acacia katechu)
Punjab
(Hoshiarpur)
Ber, babul (Acacia arabica), khair and some species of the
genus Ficus
Rajasthan
Ber and species of Ficus
Uttar Pradesh
(Mirzapur)
Ber, babul, ghont, palas, and species of Ficus
Gujarat and
Maharashtra
Ber, babul, khair, palas
Orissa
(Sambalpur district)
Kusum
Andhra Pradesh
(Vishakapatnam)
Palas
Mysore
Jalari
Madras
Ber, babul, palas, jalari (Shorea talura)
Categories of lac hosts
• On the basis of preference in use for lac
cultivation, hosts are classified into three
categories:
• Common (major hosts)-7 genera and 14
species
• Occasional hosts
• Rare hosts
Common hosts
• Excellent hosts: throughout the year and all
over in India (very popular) e.g., Butea
monosperma, Schleichera oleosa, Zizyphus
mauritiana
• Good hosts: certain restricted areas of India
e.g., Acacia arabica, Cajanus cajan, Leea
crispa, L. robusta, Zizyphus xylopyra
• Major hosts only for certain specific purposes
& in certain specified seasons e.g., Acacia
catechu (for winter brood), Ficus spp.
(summer brood)
Common hosts
•
Acacia arabica: babul
•
Ficus racemosa: gular
•
Acacia catechu: khair
•
Ficus religiosa: pipal
•
Butea monosperma:
•
Leea crispa: ban-chalta
•
Leea robusta: galeni
•
Schleichra oleosa: kusum
•
Zizyphus mauritiana:
•
Zizyphus xylopyra:
Palas
•
Cajanus cajan: arhar
•
Ficus benghalensis:
banyan tree
•
Ficus cunia: jharphali
•
Ficus lacor: pilkhan
ber
ghont
Acacia arabica
(babul)
Acacia catechu
(Khair)
Butea monosperma
(palas)
Schleichra oleosa
kusum
Cajanus
cajan
(Arhar)
Ficus
bengelansis
Ficus racemosa
(gular)
Ficus
religiosa
pipal
Zizyphus mauritiana
Ecological conditions
• lac does best in open areas with plenty of circulating air
around the host plants. When trying out new hosts,
care should be taken to confine the trials to only those
plants that are found occurring in the open or in
situations where free circulation of air is assured
• Cultivation should not be tried in deep forests
• Lac cultivation should not be tried in areas liable to
forest fires e.g., scattered trees in grassland
• Species which remain deciduous for long periods during
the hot months not suitable for summer crop season.
They can be taken up for the cultivation only for crops
which mature in cold seasons provided alternative host
plants are available in the vicinity to take on the
summer crop
Direct Sowing and Nursery
Planting
• Lac hosts propagated- either by direct
sowing at the site required or by first raising
seedlings
in
nurseries
and
later
on
transplanting them to the site required.
• Glower (1937) recommends:
• Direct sowing for khair and kusum
• Nursery sowing and transplanting for: Palas,
ber and ghont
Manuring
•
To ensure the healthy establishment of trees, suitable
manuring is highly advisable.
•
Once the trees have become well established, manuring
need not be continued.
•
Glover (1937) recommended the use of the manure which
should be dug to an area of about 1 metre radius and a
depth of about 15-20 cm around each plant
•
If artificial manure is not available, natural manure (well
rotted cowdung) may be used instead
Composition of manure
Quantity required per plant
Potassium sulphate
28.4 gms
Ammonium sulphate (or chloride)
28.4 gms
Concentrated superphosphate
0.45 kg
Soil and water
• If deficient in calcium: lime may be added
• Avoid water logging of young seedlings as
that causes mortality
• Water should be conserved for the dry
months by such devices as contour ridging,
terracing, etc.
Age of host
•
Age at which host plant is mature enough to take on
its first lac infection varies from species to species
•
Also depends on the climatic conditions of the area as
well as the methods employed for the management of
the plant which determine its vigour and vitality to
withstand the drain imposed on it by the lac infection
Species
Khair (Acacia catechu)
Ber (Zizyphus
mauritiana)
Ghont (Zizyphus
xylopyra)
Age when first mature
About 8 yrs
8 yrs
8 yrs
Palas (Butea
8-10 yrs
Kusum (Schleichera
oleosa)
About 15 yrs
monosperma)
Systematic
cultivation of lac
Systematic cultivation
PURE CULTIVATION
MIXED CULTIVATION
(single species of host
(Generally alteration of host is
plant.)
practised)
Standard
Modified system
system
Three coupe
Normal four
Two coupe
Two coupe
Three coupe
system for
coupe system
systems for
system for
system for
Rangini crop
for Kusmi crops
Rangini crops
Kusmi crops
Kusmi crops
Standard Systems
Three coupe standard system for rangini crop:
palas and ber)
(for
COUPE: field is divided into various region which are
called as coupe.
i.
The area is enumerated and divided into three
coupes (A, B, C) in ratio 3:1:3 on basis of yielding
capacity of the trees.
ii.
The time of pruning have to be adjusted according
to host plant species and local climate.
iii. A and C coupes are cultivated and rested in
alternate years and coupe B is cultivated every year
for one crop.
• Normal four coupe system for Kusmi crop
(applies to kusum)
• Area to be work enumerated
• Divided into four equiproductive
(A,B,C,D) worked in rotation
coupes
• First harvesting in each coupe serve as the
pruning for the next crop
• Each coupe is cultivated for lac once in 2
yrs, the trees in it bearing lac crop for about
6 months and resting for remaining 18
months
Modified Systems
(a) Two-coupe modified system for Rangini
crop eg: (Palas and ber)
(b) Two-coupe modified system for Kusmi
crop ( eg: kusum)
(c) Three-coupe modified system for Kusmi
crop
Mixed cultivation
• When a cross strain method of lac
production is followed, i.e., when alternation
of hosts is practised, a mixed type of
cultivation is desirable.
• Some examples of this method are:
• Alternation of palas with ber or khair
• Kusum khair alternation
Alternation of palas with ber
or khair
• Can be practiced for rangini crops where ber
or khair also occurs in an area with palas
• Best plan is to utilize palas for growing the
baisakhi crop and ber or khair for the katki
crop
Kusum khair alternation
• Kusum
cultivated
for
jethawi
crops
alternated with khair which will be
cultivated for the Aghani crop
• Four coupe system
coupes recommended
with
equiproductive
What determines a
good lac host?
Phylogenetic position
• Position of the host in the botanical
hierarchy is certainly a useful guide but
sometimes the criterion fails
• One or two species in a genus may be good
hosts and other non hosts
• E.g., Zizyphus mauritiana and Z. xylopyra
are good hosts while other species of the
genus are either non hosts or only
indifferent hosts
Sap reactions and sap density
• pH of the sap of good lac hosts generally range
from 5.8-6.2
• pH of non hosts or poor hosts may lie in the
range 5.0-5.4 as in Cassia florida, Shorea
robusta or in the range 6.2-6.8 as in Dalbergia
sisso, Aleurites fordii and Zizyphus rugosa
• Sap density of good hosts: 0.1400-0.1728
• Sap density of non hosts: 0.1955-0.2312
• High sap density may be a factor responsible for
the failure to maintain lac growth as the more
viscous liquid may not be so readily absorbed
through the proboscis of the lac insect
Ecological factors
• Response of host to climate: Time of leaf-fall
determines the success of a species to serve as
good lac-host. Later leaf-fall in the dry winter
season and a shorter interval before the
appearance of a new crop of foliage, the lower
mortality of the over-wintering individuals
among the “lac colony” is observed.
• Physical situation of hosts in a plant community:
lac is absent from thick jungles and occurs only
on the outskirts. Lac hosts are successful where
free circulation of air is ensured