Asia’s useful trees & plants
by K.L. Noatay
Baheda is a large deciduous tree found growing naturally in the Indian subcontinent. Its natural habitat starts from Burma and the East and passes over to India to Pakistan, Afghanistan, etc. Altitude-wise the zone starts at nearly 300 m and rises up to 1200 m above mean sea level. The scientific name of baheda is termanlia belerica.

• Horticultural operations for March

Rinderpest and its control
by Tejbir Singh Sandhu

Introduction:
Rinderpest is one of the major diseases of cattle that occurs in the form of epizootics. Recent reports of these diseases being reported in Pakistan is a matter of grave concern for us, especially when we share same land territory. The causative agent is a morbillivirus (family paramyxoviridae). It occurs in many strains with considerable variation in virulence between them but all are immunologically identical. Losses can be colossal and are due to deaths, loss of productivity and cost of effective prevention and control.

Cattle and buffalo of all ages are susceptible unless they have been vaccinated or have recovered from a previous infection, or in the case of calves, they have received colostral antibodies. Rinderpest usually occurs in explosive breaks. The virus is present in the blood, tissues, secretion and excretion of infected animals, reaching its peak of concentration at about the height of temperature reaction and subsiding gradually to disappear about a week after the temperature returns to normal in those animals that recover.

This virus has a high degree of affinity for lymphoid tissue and elimentary mucosa. After inhalation, it penetrates through the epithelium of the upper respiratory tract, multiplies in tonsils and regional lymph nodes, then enters blood in mononuclear cells which disseminate it to other lymphoid organs, lungs, etc. It causes striking destruction of lymphocytes leading to leukopenia. As a result of this animal is immuno-suppressed and at potential risk from secondary infection. Normally there is necrotic stomatitis and eneritis due to replication of virus in the epithelial cells of the GIT. Death is usually from severe dehydration or due to latent parasitic or bacterial infections.

Clinical findings:
Clinically there are three forms of this disease.

Peracute form:
It is characterised by high fever, congested mucous membrances, respiratory distress and death occurs one to three days later.

Acute form:
First of all there is a high fever (105 to 107°F) for several days, anorexia, fall in milk yield, lacremation and a harsh, staring coat accompany the fever in this phase which corresponds to the period of peak virus production in tissues. It is followed by inflammation of buccal, nasal and conjunctival mucosae, hyperemia of vaginal mucosa, profuse lacrimation which is accompanied with blepharospasm. Development of mouth lesions results in clear blood stained saliva. A serous or purulent nasal discharge is also accompanied. Necrotic lesions develop on the inside of lower lip, gums, on the cheek mucosa at the commissures, and on the lower surface of the tongue, nasal vulval and vaginal mucosae. The lesions are initially greyish in color, slightly raised andnecrotic which later sloughs, leaving raw, red areas with sharp edges and results in ulcers. Severe diarrhoea develops along with skin lesion in the form of scabs on perineum, scrotum, flanks, inner aspects of the thighs. Other signs include dyspnea, cough, swere dehydration and sometimes abdominal pain also. After six to 12 days, the body temperature falls to subnormal and death occurs within 24 hours. Pragnant cattle may abort at this stage.

Necropsy findings:
The important necropsy findings are observed in alimentary and upper respiratory tract and in the external genitalia in females. The carcass is dehydrated, emaciated and soiled with foetid faeces. Small discrete necrotic areas or ulcers are seen on nasal and oral cavities. Swere changes occur in the mucosa and Peyer’s patches in the large intestine, particularly at cecocolic junction giving it a striped appearance, the so-called ‘zebra stripes’. Materials sent for laboratory examination should include fixed section of lymph node and alementary tract lesions as well as fresh spleen and blood and alementary tract for antigen detection.

Identification of virus:
Marked leukopenia occurs at the height of infection. The isolation of the virus and its identification is done with washed leukocytes harvested from blood samples collected in the EDTA or preferably heparin.

Differential diagnosis:
Rinderpest can be easily confused with foot and mouth disease (FMD), hemorrhagic septicemia (HS), malignant catarrhal fever (MCF) and bovin viral diarrhoea (BVD). But it can be safely differentially diagnosed from others by some clinical experience. In the FMD, ulcerative lesions will be present between the hooves, while in the HS there will be complete lack of ulcerative lesions. The MCF really effects many animals in one herd and is characterised by specific eye lesions and nervous signs. In the BVD the mortality rate is low.

Treatment:
Since treatment against rinderpest virus is ineffective, it should not be undertaken because of the danger of disseminating the disease. Dead carcasses should be deeply buried. Caprinised vaccines is of no value in treatment and animals in the clinical stage should be immediately segregated.

Control:
The virus is very susceptible to external influences and does not persist outside the animal body for more than a few hours at normal temperatures. Since changes in PH as a result of putrification inactivates the virus within 24 hours in cadavers. So all susceptible animals in an infected herds must be slaughtered and disposed of. It is also destroyed by heat, drying and most of disinfectants. So infective premises should be disinfected as an additional precaution. Theoretically, its complete elimination awaits the development of sufficient veterinary personnel and improvement of animal husbandry systems. Control of animal movement by nomads and traders is very important. Introduction of rinderpest to a previously uninfected country is most likely to occur through the importation of infected animals particularly to zoological gardens or pushing of inoculated animals across the land borders. So it is necessary to prevent movement of both living animals and fresh animal products.

Vaccination:
The ideal vaccine is one which can be produced with varying degrees of attenuation suitable for safe and effective vaccination of cattle with different levels of susceptibility. It should also be highly thermostable, inexpensive and easy to administer under current systems of animal husbandry in India. Calves can be vaccinated at one day of age, provided they had not received antibodies in the colostrums. Otherwise vaccination is done after nine months of age. Vaccination is repeated annually. Preperation of vaccines is simplified by the common antigenicity of all known strains of the rinderpest virus.

The following attenuated viruses which are generally used for vaccination are as under:

Goat adapted virus: This produces life long immunity and is satisfactory for use in zebu-type cattle.

Rabbit adapted virus: There is doubt on the stability of this attenuated vaccine.

Chicken embryo adapted virus: Vaccine produces from this way is cheap, stable and capable of varying degrees of attenuation. The immunity produce persists for at least 16 months. It is at advance stage of field trials.

Cell culture vaccine: These vaccines have almost completely supplanted the other attenuated virus vaccines. They are easy and cheap to produce and can be freezed, dried or lyophilised and, therefore, have a long shelf life. They are capable of varying degree of attenuation and are thus safer. These vaccines produce and immunity of up to 10 years duration.

Recombinant vaccines: These vaccines are inexpensive to produce, the lyophilised form is thermostable, calves can be vaccinated at any age, even in presence of colostral antibodies. Therefore, it offers great prospects for the total eradication of the disease but before this elaborate clinical trials are required to assess the duration of immunity conferred.

Asia’s useful trees & plants
by K.L. Noatay

Baheda is a large deciduous tree found growing naturally in the Indian subcontinent. Its natural habitat starts from Burma and the East and passes over to India to Pakistan, Afghanistan, etc. Altitude-wise the zone starts at nearly 300 m and rises up to 1200 m above mean sea level. The scientific name of baheda is termanlia belerica. It belongs to the plant family combretaceae. It generally grows in forests having a mixed crop of sal, pines, khair, jamun, mango, harar, amala, etc. Well-drained calcarious soil suits it best.

The bark of baheda is bluish to ash grey in colour with uneven longitudinal furrows. Its leaves are alternate, crowded towards the end of branches, obvate elliptic in shape 10 to 20 cm long and 3 to 6 cm wide — slightly pale on the lower side. Its flowers are about 5 m in diameter of pale white to green in colour. These emit a peculiar unpleasant scent.

Baheda attains a height of about 25 to 30 m and a girth of 3 to 4 m in about 70 to 80 years. It can be recognised from a distance by the peculiar colour of its bark and its big umbrella-like spreading crown. Its wood is light grey to yellowish, cross grained and hard, though not very durable. Weighing about 25 kg per cubic foot, it can be used for construction of cheap buildings, especially for doors, windows and roof members. It is also used for agricultural implements, packing cases, firewood and for making charcoal. The abvoid oblong-shaped fruit is of 2 to 3 cm diameter. It is brownish in colour having short dense hair cover.

Baheda trees flower during April-May. Fruit appear during June-July and ripen during October-November. The trees is considered valuable for its fruits which is one of the myrobalans of commerce — the other two being the fruit of harar and amla.

Baheda fruit is favourite with monkeys and the kernel is enjoyed by village children. The leaves form a favourite fodder for domestic cattle as well as wild denizens like deer, neel gai, etc. The oil extracted from the kernel is used for its soothing effect on the hair.

Baheda fruit is used in ayurvedic and unani systems of medicine for stomach disorders, insomnia, high blood pressure, headache, diabetes, ulcer, etc. Its paste when applied on eyelids, acts as a soothing lotion. Its preparations are also used in piles, leprosy, dropsy and fever. Half-ripe baheda fruit acts as a purgative while the ripe and dried one has the opposite effect. Veterinarians also make a wide use of myrobolans, especially baheda, its extracts and various preparations.

Regeneration-wise baheda seedlings come up automatically under the mother trees. However, with a view to popularising its propagation in shamlats (village land), private holdings, roadside avenues, vacant space around state premises like school, colleges, hospitals, etc. The state forest departments raise its nursery and supply the seedlings on highly subsidised rate amounting to just Re 1 per plant.

Therefore, keeping in view the multifarious uses of baheda, it is desirable that people having vacant land or have otherwise access thereto, should plant the maximum number of baheda plants for improvement of environment, beautification of the landscape and for optimum utilisation of vacant space wherever available.

Horticultural operations for March

HORTICULTURAL OPERATIONS
— The newly planted young fruit plants should be watered at frequent intervals. The young plants should be provided with stakes for upright and straight growth. Young plants (fully established) may be given nitrogenous fertiliser in small split doses.

— The evergreen fruit plants like citrus, mango, litchi, guava and ber may be planted in the field.

— The young as well as the old trees should be irrigated regularly and more frequently as they put forth new growth. The fruit trees like those of ber, guava and loquat, which carry developing and maturing fruits, would need careful attention for their timely irrigation. To litchi trees, apply a thorough irrigation after the fruit set and continue watering at three weeks’ intervals.

— To check zinc deficiency in citrus, spray the affected trees with 0.3 per cent zinc sulphate solution (1.5 kg zinc sulphate in 500 litres of water) without addition of lime to spring flush.

— The peak season for harvesting of ber in Punjab is mid-March to mid-April.

— To check the insect pests of citrus, spray 625 ml of Nuvacron 36 SL or 670 ml of Rogor 30 EC in 500 litres of water on spring flush. For the control of withertip or die-back in citrus, spray Bordeaux mixture 2:2:250 or Copper oxychloride (1.5 kg/500 litres of water) before the flower opening.

— Check mango hopper by spraying 1.0 kg Sevin or Hexavin 50 WP or 800 ml of Malathion 50 EC or 700 ml of Thiodan 35 EC per acre in 250 litres of water.

— Spray 0.1 per cent Karathane to check powdery mildew on developing fruits of mango.

— To check fruit fly in ber, spray 500 ml of Rogor 30 EC in 300 litres of water. Stop spraying atleast 15 days before fruit picking.

— Spray vineyards with Bayleton @ 40g/100 litres of water in mid March for the control of powdery mildew and with Bordeaux mixture (2:2:250) in the last week of March for the control of Anthracnose.

ORNAMENTALS:
— If the seeds of summer annuals have not been sown in the nursery, the same may be sown at the earliest.

— Winter season flowering annuals should be selected for seed collection. Plants should be carefully examined and true-to-type may be labelled. The less perfect in bloom/colour should be eradicated.

— Some of the winter season flowers, which are still in good conditions, should be given proper irrigation to prolong their flowering time. Their faded flower should be removed simultaneously.

CHRYSANTHEMUM:
— Suckers of chrysanthemum, which were planted in the raised beds in January or February, can now be transplanted in 10 cm pots (that of large flowered varieties). A few suckers of the same type can be planted in beds for getting cuttings in July. The developed suckers of small flowered varieties may be transplanted in the well manured beds.

PERMANENT PLANTS:
— During this month, all types of permanent ornamental plants including trees, shrubs and creapers can be planted. For their proper growth and development proper size and properly filled up tree pits should be prepared.

The selected samplings should be healthy and disease-free. The size of full-grown plants should be kept in mind while planting of permanent trees, shrubs and creepers.

The plant-to-plant distance should be adjusted accordingly. Hedges which are grown from seed can also be sown now.

LAWNS:
— The lawns can be developed in this month. The grass roots/suckers of some selected varieties e.g. "Calcutta grass" (cynodon dactylon) or "Koreen" grass can be dibbled in the well-prepared soil.

After dibbling the grass roots/suckers, it is advisable to press the area with some roller. In the initial stages (and if possible thereafter also) irrigation of the lawns through sprinklers is the best.

POT PLANTS:
— Best time for the propagation and manuring of shade loving and other pot plants like dracaena, pedilanthus, alocasia, chlorophythum, ferns, rhoeo discolour, sansevieria etc.

The plants, which had been growing in a particular pot for more than 3-4 years, should be taken out from the pot if required, divided/multiplied into two or more than two parts of the each (depending upon their present size and health) and then replanted in pots by using fresh and rich pot mixture.

BULBOUS PLANTS:
— If the summer flowering bulbs could not be planted so far, the same can be planted now in the well prepared soil or in the pots.

— Progressive farming, PAU