Hybrid seed production and flowers
By Manish Kapoor
EVEN before Shull (in 1991) propounded the classical theory of “hybrid vigour” in plant breeding for the first time, F1 hybrids in ornamental crop s were known. However, hetrosis breeding in floriculture did not gain momentum, though in 1909 Benary Seed Company, Germany, released “Prima donna”, a F1-hybrid variety in begonia.

Farm operations for July

Oxytocin: a misunderstood hormone
By K.B. Mathur

THE peptide hormone oxytocin is a highly potent and valuable drug and its usefulness in human as well as veterinary medicine is well established. Persistent efforts to get the drug banned have failed as the Health Ministry and its Drugs Technical Advisory Board (DTAB) feel that the demand is unjustified. The official position of the government on this issue was clearly stated in the Lok Sabha by the Minister of State for Health and Family Welfare, Mr N.T. Shanmugam, on November 30, 1999, in response to Parliament question No. 309 (IDMA Bulletin XXXI (II) March 21, 2000). Accordingly, the drug would be available to the user only against the prescription of a registered medical/veterinary practitioner so that its indiscriminate use or misuse is checked. However, since totally baseless and illogical reports regarding the harmful effects of oxytocin and the milk from oxytocin treated cattle continue to appear in the media, it is important that the public at large gets a correct picture of the whole issue.

Oxytocin is a naturally occurring hormone belonging to the class of rather sensitive and relatively unstable organic compounds called “peptides”. Insulin, ACTH, vasopressin and LH-RH are the other examples of hormones falling in the category of peptides, which are equally known therapeutic agents for the treatment of various physiological disorders.

Oxytocin is secreted endogenously in all mammals for induction and maintenance of labour as well as for initiation of milk let-down in the female. Since it is a peptide hormone, it disappears rapidly within two to six minutes from the blood stream due to the action of various enzymes. Synthetic oxytocin is, therefore, used quite commonly in human as well as veterinary medicine.

It is the drug of choice to induce rhythmic contractions of the uterus and augment uterine contractions during desultory labour. It is prescribed to control and prevent bleeding after childbirth and abortion. Oxytocin is also used for the induction of therapeutic abortion and management of inevitable or incomplete abortion. Equally important is its clinical use for promotion of milk ejection in lactating women who experience difficulty in breast feeding and for treating cases of breast engorgement and mastitis.

Oxytocin is used universally in the livestock industry to increase let-down of milk and expulsion of retained placentas after delivery. The hormone is also used to aid delivery in young animals when the female has been in labour for an extended period. It is also employed frequently as an adjunct to antibiotic therapy for the treatment of mastitis in milch cattle. Oxytocin is, thus, a highly efficacious life-saving drug that cannot and should not be dispensed with on the basis of false notions and scientifically unsound charges against its use.

The reports on the harmful effects of milk produced by oxytocin-treated dairy cattle are quite misleading and not based on scientific facts. Whether secreted endogenously in response to natural stimuli or administered exogenously, oxytocin produces the desired effect within minutes and gets metabolised rapidly leading to inactive products. Till date, there is not a single report which demonstrates the presence of this hormone in the milk. Those who imagine that it may escape the action of degrading enzymes and seep into milk in traces should also realise that in such a situation, all the breast-fed infants and newly born calves must be constantly exposed to these traces of oxytocin in mother’s milk all the time without facing any health hazards whatsoever. The reason is that if at all ingested orally along with milk, oxytocin is bound to be digested like other proteins and peptides due to action of gut enzymes and gastric acids and cannot be absorbed from the intestines to reach the blood circulation again. Likewise, there is no question of milk produced by oxytocin-treated cattle being harmful to those who consume it regularly. First, due to its being unstable at room temperature, traces of oxytocin would be inactivated simply on storage and boiling of milk. Secondly, it would not escape the digestive system of the person who consumes it.

The results of a study carried out by scientists of the Department of Animal Science at Cornell University, Ithaca, New York, published in the Journal of Dairy Science in 1991 clearly show that the administration of oxytocin at a dose as high as 20 IU, at each milking twice daily, not only increases the milk yield substantially but also maintains greater persistency during lactation without changing the composition of milk. The daily administration of oxytocin for 305 days apparently had no effect on the health of the treated cows, particularly on the length of the oestrous cycle. So far as the dairy owners restrict the use of exogenous oxytocin to the recommended dose (1-3 IU. per milking) for the complete recovery of milk already produced and available in the mammary glands, there should be no reason for any alarm whatsoever.

Another study carried out at the Dairy Cattle Physiology Division of the National Dairy Research Institute, (NDRI), Karnal, Haryana, also supports the above findings. According to NDRI scientists, the perception that the use of oxytocin for milk let-down in pregnant animals may cause abortion is also unscientific, since oxytocin receptors remain absent throughout pregnancy and appear only towards the end of the gestation period.

On the basis of scientific facts stated earlier, it would not be wrong at all to use oxytocin in appropriate doses on dairy cattle to facilitate increased milk let-down, particularly in a country like India where there is so much of a gap between demand and supply of milk.

The current tirade and misinformation campaign against the use of oxytocin for milk let-down in dairy cattle is highly unjustified and should be stopped forthwith.

Hybrid seed production and flowers
By Manish Kapoor

EVEN before Shull (in 1991) propounded the classical theory of “hybrid vigour” in plant breeding for the first time, F1 hybrids in ornamental crops were known. However, hetrosis breeding in floriculture did not gain momentum, though in 1909 Benary Seed Company, Germany, released “Prima donna”, a F1-hybrid variety in begonia. It was only during World War II and later 50s that hetrosis breeding attracted attention of flower breeders. Thus, the first hybrid of double petunia was developed in Japan and later F1-hybrids were developed in ornamental flowers in the Netherlands, Denmark, Germany, the USA and the UK. The few important hybrids were first released in Petunia (in 1940-50); geranium single (1960); antirrhinum, pansy, marigold and zinnia (1965); ageratum (1966); geranium double (1970); dianthus, impatiens and portulaca (1976-77); gerbera (1980) and carnation (1981). There is continuous research for developing new F1-hybrid flowers. Therefore, every year new and more attractive hybrids are being released by different seed companies in the world. Now, F1-hybrids are available in many flowers from A (antirrhinum) to Z (zinnia).

The main advantage of F1-hybrids is the unique combination of increased vigour and uniformity. In addition, the F1-hybrids have other advantages also like dwarf and compact plants, profuse basal branching, free blooming, early and abundant flowering, longer blooming season, doubleness, larger flowers, attractive colour and type, tolerance to heat, humidity and resistance to diseases. In ornamental plants, hybrid vigour is desired and expressed as uniformity in vigour and flower size, as in the case of bedding plants e.g. petunia, geranium, etc. In bedding plants, uniformity in height, with basal branching, simultaneous flowering and its long duration are very much desired to produce a carpet-like effect from a distance. Flowers should look fresh and stay longer on the plants, and this has been achieved by incorporation of sterility, avoiding pollination and seed set which in turn, prolonged freshness.

There are constant efforts by flower breeders to produce new and more attractive hybrids. Hybrid technology has been tailored to meet the requirements of new bedding plant technology using automated system, smaller containers, shorter crop time, energy stress, singulated seeding, etc.

It is evident that India is far behind the latest technology of F1-hybrids in flowers. Obviously there has been no appreciation in India of the potentialities of hybrids in flowers. Further, hybrid seed production in ornamental plants is labour intensive and has a good potential for the employment of youth in rural and suburban areas. It may also generate gainful income by setting up ancillary industries dealing with equipment and other facilities needed.

With the favourable climatic conditions of Jammu and Kashmir, Himachal Pradesh and Punjab, commercial production of F1-hybrid seeds for export can be attempted by seed companies and government agencies so that the country earns a good amount of foreign exchange. Already in Punjab, some private growers have taken up seed production of open pollinated varieties of ornamental flowers for export and are thinking of expanding this venture to hybrid seeds as well. Such export-oriented programmes are required to be promoted and encouraged in view of the “focus thrust area” assigned to floriculture by the Agricultural and Processed Food Products Export Development Authority (APEDA) and the Government of India. One of the pioneer companies which has undertaken this venture is Plantsman’s Seeds, Patiala, having 250 acres under production of flower seeds for export.

Obviously, the infrastructural facilities like green house will have to be developed to protect the hybrid flower seed production programme against the vagaries of weather. It is necessary that competent manpower is trained to take up the development work of F1-hybrids. Unfortunately, technical manpower in floriculture, both at the experimental and production levels is inadequate. Thus, the field staff should be trained in pollination, hybrid seed collection and processing methods. Indian planners and policy makers should think of non-conventional areas for creating new export ventures.

Floriculture is no longer considered to have an aesthetic value alone as it has already proven to be useful in export trade, and India must strive to export the potential of labour cost, manpower and favourable climate in view of earning foreign exchange.

Harmless variety of khesari dal
By Shirish Joshi

AGRICULTURAL researchers under the leadership of Dr Adel el-Beltagy, head of a research centre in Syria, have developed a new variety of khesari dal which is not poisonous.

This is being hailed as a breakthrough for the drought-prone countries. The existing forms of khesari dal (Lathyrus sativus L. family: leguminosae), also called grasspea, can live for months without rain, but it is highly toxic to humans.

It can cause paralysis, especially in children, if consumed in large quantities. The health of many people in India is believed to have been damaged. Occasional use is harmless. Seeds, if soaked in water for 24 hours before cooking, are not toxic.

The new strain of khesari dal is just as hardy and high in protein. The new plants are to be tested out in drought-prone countries, including India. Khesari is typically the last plant standing in times of drought.

Poor people know the effects of eating khesari dal but live under such desperate conditions that they have no other option but to eat it. The agricultural researchers wanted to make it a safe one.

The new strain was developed by mixing West Asian versions of the plant, which are lower in toxins, with the Asian and African varieties. The result is a type of khesari dal which is safe to eat and will grow in some of the harshest climates in the world. The new variety has the added bonus of being tasty.

The existing strains of the plant are already grown in India. Most of the crop is fed to livestock which is not affected by the toxic chemicals in the plants.

The khesari is a legume crop, part of the family to which belong peas and beans.

The seeds are boiled and consumed as a pulse and can be used in dal preparation and bread making. Leaves can be consumed as a vegetable after boiling. Plants are valued for green manure.

Mixed with oilcake and salts, khesari dal is used as a nutritive feed for poultry and livestock. Oil from khesari dal is a powerful and dangerous cathartic that contains a poisonous principle.

The origin of khesari dal is unknown. However its presumed centre of origin is Southwest and Central Asia. The crop is also widely cultivated in Central, South and East Europe, the Mediterranean and Africa. In many parts of India, it is cultivated up to 1,300 metres.

The crop is tolerant to extremely dry conditions in drought-prone areas as in Ethiopia and also tolerant to excessive floods as in Bangladesh. When fed alone, fresh young plants are reported to be harmful to horses. However, cattle, rabbits, and sheep can consume large amounts without any ill-effects.

In India, khesari dal occupies about 4 per cent of the total pulse crop and constitutes about 0.3 per cent of the total pulse production, with about 1.6 million hectares, producing about 0.5 million metric tonnes of seed.

Dr Adel el-Beltagy ate the new variety and found it to be delicious. The new plant will grow for months without rain.

Farm operations for July

Ornamentals:

 With the commencement of rainy season, the plants of ornamental trees, shrubs and creepers can be planted in well-prepared pits. The size of the pits for trees should be 3’x3’ and for shrubs and creepers 2’x2’.

• Propagation of most of the shrubs like hibiscus chandanil and bougainvillea can be done through cuttings. The thickness of cuttings should be of pencil size having 4 to 6 buds. To save the cuttings against rot, the same may be treated with some fungicide solution e.g. Bavistin.

— Progressive Farming, PAU