Practical No 1:
To Study classification and morphological characteristic of cotton crop.
Objective:
To study about classification and morphological characteristic of cotton crop.
Theory:
Classification
Taxonomical Classification
· Belongs to genus Gossypium of Malvaceae family.
· Has 35 species include both wild & cultivated species. The cultivated species are :
A. Old world cotton (n=13), Indian/ desi Cotton
1. Gossypium arboreum L.
2. Gossypium herbaceum L.
B. New world cotton (n=26), American Cotton
1. Gossypium hirsutum L., American/ Mexican cotton
2. Gossypium barbadense L., Peruvian cotton
Morphology
· In wild state, cotton is perennial but it is cultivated as an annual plant.
· Cultivated cotton is an herbaceous plant with tap root system.
· Main stem is erect & has many branches that developed from the buds located at the nodes of main stem.
· Two buds at the base of each leaf petiole.
· True axillary bud develops into monopodial or vegetative branch that bears growing bud & leaves at the tip.
· The accessory bud generally develops into sympodial or fruiting branch that bears flower at tip.
· Flowers develop at the node opposite to a leaf in fruiting branches.
· Flowering starts & proceeds from the base to upward direction.
· Fruit is an enlarged ovary that develops into 3-5 loculed capsule or boll.
· When boll ripened the capsule cracks along the sutures where the capsules meet, & mass of cotton fiber expand out wards.
· No. of seed in a boll is 25-50.
· Test weight (1000 seed) is 90-150 g.
· Cotton fiber is an elongation of an epidermal cell of the seed coat.
· The long outgrowth of epidermal cell forms the lint & shorter forms fuzz.
· Length of fiber ranges from 20-50 mm.
Practical No 2:
Numerical calculation of fertilizer dose, yield estimation and seed rate of cotton
Objectives:
To calculate fertilizer dose of cotton.
To Calculate seed rate of cotton.
To estimate yield of cotton.
Practical No 3: Study of classification and morphological characteristics of sugarcane including noble cane and nobilization.
Objectives:
· To study classification and morphological characterstics of Sugarcane.
· To study about Nobel cane.
· To study about Sugarcane nobilization.
Theory:
Classification of Species
Sugarcane is a tropical plant belonging to the family Gramineae, class monocotyledonous and order glumaceae. Sugarcane is known by the scientific name Saccharum officinarum L. In fact Officinarum is one of the species. Saccharum officinarum, S. sinensis and S. barberi are the three main cultivated species of sugarcane. S. spontaneum and S. robustum are the wild species which are used for breeding and research study only.
1. Saccharum officinarum
It is also called “noble cane”. These are stout, soft, thick as well as thin and have luxuriant growth habit. These juicy canes are good for chewing purpose. These canes contain high sugar content, low fiber and produce high tonnage. The clones are high susceptible to moisture stress, low temperature, saline, alkaline and water logged condition. It has 2n=80 chromosomes. At present they are grown for chewing purpose.
2. Saccharum sinensis
This is also known as “Chinese cane”. This species of sugarcane is indigenous to North-eastern India or south east China. This species is characterized by long internodes and thin stalk, long and narrow leaves, low to medium sucrose content and early maturity. Stems have high fiber content and yield poor quality juice. These are susceptible to moisture stress condition, mosaic and red rot disease. The chromosome number is 2n =111 to 120.
3. Saccharum barberi
This species derives its name from S/C scientist Dr. C.A. Barber of India and is known as “Indian species”. This species is also indigenous to North-eastern India. These canes are hardy, drought and frost resistant to some extent. Canes are characterized by short and thin stalk, narrow leaves, low to medium sucrose content and early maturity. The clones are highly tolerant to high and low temperature, saline, alkaline and water logged condition. It has chromosome number 2n =81 to 124.
4. Saccharum robustum
This species is discovered in New Guinea(Australia). The stalks are long, thick and vigorous growing. It is rich in fibre and poor in sugar. This is a wild species and not suitable for agricultural production. The chromosome number is 2n = 60 and 80.
5. Saccharum spontaneum
It is also known as wild cane. The cane is very thin and short, the leaves are narrow and hard. The sugar content is very low (2-10%). This species is useful for evolving hybrid varieties particularly to obtain disease and stress resistant types. The chromosome number is 2n = 40-128.
Morphology of sugarcane:
· Sugarcane is a tall perennial plant growing erect even up to 5 or 6 metres.
· The plant is composed of four principal parts, the root system, the stalk, the leaves and the inflorescence.
A. Root System
· The root system is fibrous and consists of two types of roots, namely 'sett roots' and 'shoot roots'.( Sett roots are fine and highly branched roots which sustain the growing plant in the first weeks after germination and are mostly temporary. Shoot roots are a second type of root which emerge from the base of the new shoot 5–7 days after planting)
· When sugarcane sett(single bud cane) is planted in the soil and covered with moist soil, the root primordia (translucent dots) situated at the base of every cane joint is activated and produces roots.
· These roots are known as 'sett roots' and are mostly temporary.
· These are thin and much branched and function for a limited period. These roots provide moisture and nutrients for the growing primary shoot until it forms roots of its own. Later on these 'sett roots' cease to function and die.
· After the emergence of the primary shoot from the bud, other roots are produced from lower rings of the lower nodes of the shoot.
· Later, this process occurs progressively in upper rings of the nodes near the soil surface. Those formed first go downwards, whereas those formed near the soil
· Surface roots grow in upper layer of soil for providing anchorage for the plant. These roots produced from shoot are known as 'shoot roots'.
· These are permanent roots and are thick, fleshy and white in colour. New roots are continually produced from tillers.
B. Stalk
· Known as "millable cane" meaning suitable for cutting. It develops from the bud of another stem piece planted for vegetative propagation.
· The stem pieces used for planting are known as "setts" which contains one or several buds. The bud sprouts under favourable conditions gives rise to a primary stalk from which secondary stalk, thus inducing tillering process.
· Sugarcane stalk is composed of many distinct nodes and internodes. It is above ground portion of the plant which bears leaves and flowers.
· A small portion of the stalk is below ground which is called as rootstock.
· The node is the base of the leaf. At each node there is a bud, sometimes known as an 'eye' appearing on opposite sides of the cane. These buds are protected by the leaf sheath, which is folded tightly around the internode. Buds are shell shaped. On the tip of the bud a germination pore is present through which the sprouting shoot emerges.
· The nodes have
(i) Root band with primordial root
(ii) Bud which is characteristic to each variety
(iii) A wax band below the node and
(iv) A growth ring above the node.
· Immediately above each node, two or three translucent(semi transparent) dot like structures known as root primordia appears in root band. These root primordia give rise to 'sett roots' as indicated earlier.
· Just below the bud is a raised portion known as the leaf scar.
· The internodes vary in shape, length and thickness depending upon the variety and growth conditions.
· Various internode shapes are-cylindrical, curved.
· Sugarcane produces branches that grow from below the surface of the soil.
· The underground portion of the stem tapers (reduce in thickness towards one end.) rapidly and from the lateral buds of this region the shoots develop. These are called tillers.
· Single cane may produce as many as 20 to 40 tillers depending upon variety and environmental conditions.
C. Leaves
· The leaves of the cane plant grow alternately on opposite sides of the cane stalk from the nodes.
· Leaf of sugarcane consists of a sheath and the blade. The sheath is attached to the stalk by a basal ring and completely clasps the stalk. It is normally a light green in colour. The outer surface of sheath is often hairy.
· The leaf blade is long, flat structure varying from one to one and a half metres in length and 5 to 7 centimetre wide.
· The colour of blade varies from yellowish-green to very dark green depending on both the variety and nutritional status of the plant
· The midrib is prominent (distinct) with a groove (a long, narrow cut or indentation in a surface) on the upper surface.
· The leaf edges are generally serrated (sawlike).
· The projection from the leaf sheath near the blade joint is the auricle(ear like), which does not occur in some of the varieties.
At the junction of the sheath and blade there is a membraneous attachment known as the ligule which bears long hairs. (The ligule play a role in the overall health and function of the leaf. By sealing off the junction between the leaf blade and sheath, the ligule helps prevent the entry of pathogens and pests into the plant's vascular system, thus indirectly supporting the plant's ability to photosynthesize by maintaining leaf health and integrity.
D. Inflorescence
· The inflorescence of a sugarcane generally called the 'arrow' is an open panicle. It is long (30 centimetre or more) and tapering (narrow toward end).
· The arrangement of the spikelets is racemose, that is, the oldest flowers are at the bottom and the youngest at the top.
· The flowers open in succession over a number of days.
· Flowers have both male and female organs, but not all produce fertile pollen.
· Some of the varieties have fertile pollens but they are usually small and low vitality.
· Sugarcane usually flowers at the age of ten to twelve months, but some varieties in north India do not flower at all. Due to this fact cane has so long been propagated vegetatively by cuttings of sugarcane. Cane produced from seed is not so vigorous, but it is important for breeders.
Practical No 4: Numerical calculations in relation to seed rate, yield estimation and commercial cane sugar (CCS).
Practical No 5: Study of classification and morphological characteristics of potato and potato tuber.
Objectives:
· To study about classification of Potato.
· To Study morphological characteristics of potato and potato tuber.
Theory:
Potato belongs to the genus Solanum, in the family of Solanacee. The commerically cultivated potato belongs to the species Solanum tuberosum.
The commercial potato generally belong to the two species.
1. Solanum andigenum:
· It is not very common.
· Plants have thin and long stem, small and narrow leaflets.
· Flowers are produced more pro-fusely.
· It has long stolons and mostly coloured deep-eyed tubers.
· It is frost tender. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects.
· It cannot grow in the shade. It prefers moist soil.
· It is perennial.
2. Solanum tuberosum:
· It is more common.
· Plants have shorter and thicker stem, larger and wider leaflets.
Morphological Characterstics:
· The potato is perennial but as a crop it is treated as an annual.
· It is vegetatively propagated by means of tubers.
· The tuber is an enlarged underground stem produced on the end of a stolon and not on the roots.
· These tubers are morphologically stems. They possess eyes that is, buds.
· The tubers also contain lenticels (respiratory structures) like stems of other plants.
· The upper part of the sprout develops into the aerial stem.
· The aerial stems are round or angular, pubescent or glabrous, green or purplish.
· The stem is branching types. It is erect when young, and spread as the plant grows.
· The leaves of the potato are alternate and compound (occasional bicompound).
· The leave Aries along the stem in a spiral arrangement.
· There are three to four pairs of leaflets arising in succession along the rachis.
· The leaflets are more or less opposite. There is a large terminal odd leaflet.
· The root of potato is adventitious, arising from the base of a sprout. The root growth is usually restricted to top layers, at a depth of about 20-25 centimetre from soil surface. In rich soils roots of some varieties may reach up to a depth of 90-100 centimetre.
· The flowers of the potato plant are in terminal clusters. Each flower normally has five stamens, two-celled pistil, five sepals and five petals united for about half their length.
· Most varieties of potato bear infertile pollens and hence fruits or berries are not generally formed. In some of the varieties fruits or berries are formed.
Practical No 6: Study of classification, morphological characteristics and differences between two species of jute.
Objectives:
· To study about classification of jute.
· To understand about morphological characteristics of jute.
· To study differences between two species of jute.
Theory:
Morphology of Jute
· Family: Tiliaceae
· Habit: An annual cultivated herb
· Root: Taproot system (numerous branches developed), in case of C. capsularis adventitious root developed(roots developed on stem which facilates in exploring a wide range of area for nutrition).
· Stem: Herbaceous, erects cylindrical, solid, slender (thin), smooth at the top but rough at the base, branching near the top, green in color, mucilaginous(viscous).
· Leaf: Simple, alternate, deciduous (shredding leaf annually), petiolate, petiole long, auriculate, lower two serrations prolonged into fine pointed auricles, venation reticulate(vein linked together in web like form.)
· Inflorescence: Solitary(alone), opposite to leaves.
· Flower: Complete, pedicellate(pedicle present), small, bisexual, yellow in color.
· Calyx: Sepal-5, polysepalous(separated sepals), narrow, green in color, aestivation velvet.( When the margins of the sepals are in contact with each other without overlapping
· Corolla: Petal-5, polypetalous, aestivation- imbricate (margin of petal overlapping) .
· Androecium: Stamen many, polyandrous, filament long and thin, anther small, kidney-shaped, 2- lobed.
· Gynoecium: Carpels-5, syncarpous(carpels united), 5-locular with numerous ovules, style short.
· Fruit: Capsule
a. Corchorus capsularis(India): bitter taste due to presence of ‘corchorin’ also known as tito paate.
b. Corchorus olitorius (Africa): Almost tasteless known as mitho paate.
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