Seedling mangoes of Hoshiarpur
HOSHIARPUR can still claim to be a treasure house of seedling mangoes.

Polyculture fish model
STUDIES on the relative growth performance of exotic carp in different culture systems under the agro-climatic conditions of Palampur have revealed that the production per unit area of grass carp and common carp is better in polyculture as compared to the monoculture because of the reserve organic food being high in polyculture ponds which favour the high production per unit area.

Why farmers burn rice straw

By S.S. Brar and Sanjeev Kumar

AGRICULTURAL intensification in Punjab is an inevitable consequence of the increasing population pressure and decreasing per capita land area. As recently as 1970s, the increase in food production in most developing countries was achieved by bringing virgin land under cultivation. Presently, however, reserves of potentially arable prime agricultural land are rapidly dwindling. Therefore, agricultural intensification with improved technology is inevitable, especially for states like ours that presently practice predominantly intensive agriculture. The intensive agricultural systems based on nutrient mining and fertility-depleting practices accentuate depletion of soil organic carbon (SOC). Restoration of such degraded soils by enhancing soil quality is important to increase productivity, through its role in supplying nutrients, nutrient recycling, improving soil/plant available water resources, increasing soil buffer capacity and stabilising soil structure. The fast dwindling non-renewable resources of energy and industrial raw materials is cause of great concern for the scientists, policy makers and public. It is estimated a five-tonne crop of rice removes about 150 kg of nitrogen, 20 kg of phosphorus, 150 kg of potassium and 20 kg of sulphur. About 75 to 80 per cent of the potash, one-third of nitrogen and sulphur and one-fouth of phosphorus remain in the straw. It is obvious that such a huge drain on nutrients will continue to impoverish the soils unless these are replenished through recycling.

In the Indo-Gangetic plains region of India nearly 12 million hectares is accounted for rice-wheat rotation. Harvesting of these crops with combine harvesters is very popular with the farmers of Punjab, Haryana and western Uttar Pardesh on account of high labour wages and anxiety of the farmers to get the crop produce collected and marketed at the earliest. Tentative estimates show that in Punjab 75 to 80 per cent area under rice is machine harvested which leaves behind enormous quantities of organic matter. Wheat straw is mainly used as animal feed, whereas rice straw is inferior in feeding quality and hardly used for fodder, at east in Punjab. At present three-fourth of the crop residue amounting to 70 to 80 million tonnes of rice is disposed of by burning. Crop residue, a renewable resource, is an important component in an ecosystem stability of the world’s agricultural land. Developing techniques for effective utilisation of this vast resource is a major challenge.

Almost all the daily newspapers of northern India published reports on the incidence of the thick cloud of smog that enveloped many parts of Punjab and Haryana on October 15. People experienced reduced visibility, besides irritation in eyes and throat. This smog was attributed to the large-scale burning of rice straw by farmers. The reports of a ban on the rice straw burning in open fields are not correct as it has not been banned in India. The burning of the residue is not only a source of atmospheric pollution but also leads to loss of rich renewable soil rejuvenating organic resource. Farmers opt for burning as it is a quick and easy approach for disposal of residue and enables farmers to plant next wheat crop well in time. This is the primary reason for burning rather than incorporating the same for soil enrichment. Soil tillage for managing crop residue is a basic and important component of agricultural production technology. The efficiency of available land preparatory implement is often low. The most commonly used "off-set disc harrow" fails to incorporate the rice stubbles and above ground biomass properly. Shredding of the above-ground parts (to about 25-30 cm) also does not help as the off-set disc harrow tends to glide over rather than going deep and improving the incorporation. The time available for tillage operations to be performed, the energy requirements, logistic support and a range of complex socio-economic factors affect the choice of residue management method. Even after mechanisation of various tillage operations, the farmers have not adopted the modern specialised land preparatory implements like the mould board plough, disc plough, rotavator or strip-till-drill techniques, etc., because of their being costly. They continue to depend on shallow land scratching implements which though were suitable and met the tillage needs under upland conditions adequately of light alluvial soils, yet they prove quite ineffective in dealing with specialised land management requirements of wet land rice-based cropping systems. There is a need to evaluate and develop suitable machinery that can do this job with less draft and is cost effective.

Another potential problem from the incorporation of crop residue with wide C/N ratios is that caused by immobilisation of inorganic nitrogen. In Punjab, the harvesting of rice normally extends from the first to third week of October and thus a gap period of 25 to 35 days is available after the harvest of rice and sowing of wheat. This short turnaround period accompanied with declining temperature further curtails the rate of decomposition. Consequently partial decomposition of improperly incorporated residue in the soil may reduce the yield of subsequent wheat crop during initial years as compared to burning. Partially decomposed straw has been found to produce phytotoxins, besides this straw near the soil surface can cause blockage of the seed drill leading to reduction in seeding depth, hence poor plant stand.

The preliminary work carried out at PAU, HAU and GBPUA&T indicates that when properly incorporated, the wheat crop performance following residue incorporated and residue burning situations tend to be alike. However, often to achieve this status these require gestation period of three to four years before equilibrium conditions set in. Efforts made to investigate the role of cellulolytic micro-organisms for rapid decomposition of residue are, however, unable to provide conclusive results.

Therefore, thrusts need to be placed for developing efficient agrotechnology for crop residue recycling in machine-harvested areas as an alternate to burning. This infers development, validation and adoption/adaptation of appropriate crop residue-cum-tillage systems for different sized farms and for a wide range of soils and climatic environments.

Seedling mangoes of Hoshiarpur
By A.S. Bindra

HOSHIARPUR can still claim to be a treasure house of seedling mangoes. There is a popular marriage song "Chhad ke desh Doaba, ambian nu tarsengi", which means "O girl, you will miss the sucking mangoes after leaving Doaba".

Juicy (sucking) type mangoes have a unique place in Hoshiarpur district of Punjab. A large number of old neglected orchards are growing along the sides of roads and boundaries of the fields. Of the total area under mango cultivation in the region about 90 per cent is occupied by such genotypes. With the increase in irrigation facilities quick return crops such as potato, sugarcane and sunflower are fast increasing in area, partly at the cost of mango trees. In the kandi area of the district, where no such facility exists, this onslaught of "modern" agriculture is less manifest. Here these mango trees are the mainstay of several farmers. Income from some good trees may be as high as Rs 4,000 to Rs 6,000 per tree every year. It is surprising that such returns are possible in trees growing under semiwild conditions where they get little management.

A lot of variation is present in the fruits from these seed propagated trees. Some have good characteristics like pleasant taste, high pulp-stone ratio, attractive colour, pleasing aroma, etc. The fruit of some of the trees ripen as late as in the middle of August when the crop is virtually over in the country. Others are dwarf in stature making them eminently suited to modern scientific fruit growing. Occasionally there are trees that bear fruit in clusters, some have 20 to 30 fruits per cluster. Dr J.K. Sharma, horticulturist at Krishi Vigyan Kendra, Bahowal, Mahilpur, Hoshiarpur, has been taking keen interest in studying these trees through extensive surveys. The author had a taste of his efforts when we walked miles in light textured soils with burning sand entering into our shoes.

Dr Sharma has identified over 20 seedlings having desirable characters. Of these four are being further evaluated by university scientists for adoption by the fruit growers of the region. Dr P.S. Kahlon, his Director, has been making a useful contribution by encouraging him in his missionary work.

Mango, malformation, the bane of mango cultivation in the region, is virtually absent in several genotypes, making them good parent for a breeding programme. Some trees are resistant to other two enemies of mango — hopper and anthracnose.

Unfortunately this wealth is vanishing. Many old orchards with huge seedling trees have been felled for timber, since the wood prices have gone up steeply. Further, the land is under pressure for use for industries or housing. It takes just a few minutes to destroy a mango strain by cutting the mother plant but may take millions of years to get another one.

Polyculture fish model

By C.M. Kumbhkarni

STUDIES on the relative growth performance of exotic carp in different culture systems under the agro-climatic conditions of Palampur have revealed that the production per unit area of grass carp and common carp is better in polyculture as compared to the monoculture because of the reserve organic food being high in polyculture ponds which favour the high production per unit area.

A comprehensive polyculture fish model has been evolved by scientists of Himachal Pradesh Krishi Vishvavidyalaya, Palampur, for the mid-hill agro-climatic zone of Himachal Pradesh. Three exotic fish species — common carp, grass carp and silver carp — with different food and feeding behaviour in the ratio of 3:2:1 are being cultured together in a single pond under semi-intensive culture practices with the stocking density of 15,000 fingerlings per hectare in this model. The production efficiency of this polyculture fish model has been increased by 25 per cent by improved fish farm management practices and the research trials conducted on nutritional requirement, species ratio and stocking density in a semi-intensive polyculture system, according to Dr J.M. Nigam, Dean, College of Veterinary Sciences.

A revolving fund scheme in the 0.4 had fish farm on the university campus for demonstrating the production efficiency of this system has proved viable in as much as it is serving a dual purpose of demonstration to the farmers and generating financial resources for self-sustainability, explained Dr Nigam.

The Dean further said that the production efficiency of this model was evident from the reports of annual production worked out as four tonnes per hectare and the net profit estimated at Rs 60,000 per hectare per year. Many more such models are required to be evolved for different agro-climatic zones of the state for the diversification of conventional agricultural practices so as to uplift the socio-economical status of the poor farmers.

The university has compiled a comprehensive list of 57 species of fish faunal resources from Himachal Pradesh, indicating threatened, vulnerable and amenable species. The purpose is to use it as a baseline data for future strategies on fisheries development in the state.

The genetic improvement of common carp stock in the university farm by selective breeding, repeated segregation and selection at different growing stages as well as managemental care are reported to have significantly contributed to the improved fecundity rate, higher survival rate and better growth of fries and fingerlings.

In view of the vast potential of both capture as well culture fisheries in Himachal Pradesh, experts feel that a tremendous work is required to be done in respect of fisheries research and development in the state. Each agro-climatic zone requires a specific aquaculture model to be evolved with standarised package of practice in the zonal jurisdiction itself. The objectives identified for the future by the university include the development of technology for the conservation and rehabilitation of various endemic fish species such as mahseer and snow trout, which had main stay in capture fishery a few decades ago, but they are on the verge of extinction.

Pulses

— In lentil use varieties LL-56 or LL-147. For higher yields, inoculate the seed with rhizobium culture. Apply 10 kg of urea and 50 kg of superphosphate per acre at the time of sowing. If the rhizobium culture has not been used, then apply 100 kg of superphosphate per acre at the time of sowing.

— In gram, use varieties PBG-1 or C-235 in the submontane districts, whereas GL-769 or GPF-2 varieties be used in other districts. The sowing must be completed immediately as further delay in sowing results reduction in yield. Prefer PDG-3 variety under rainfed conditions.

— Treat the seed with Bavistin and Thiram (1:1) or Hexacap/Captan/Captaf at 3 g/kg seed for the control of blight. Grow resistant varieties, C-235 and PBG-1.

— Treat the seed of pea with Bavistin at 1 g/kg seed for control of wilt.

Rapeseed and mustard:

— Under November sowing, transplanting of gobhi sarson is more profitable than direct sowing. Use 60 days old seedling of gobhi sarson. Raya RLM-619 can also be sown during this month but African sarson PC-5 gave more seed yield than RLM-619.

— To early sown raya, apply 45 kg of urea per acre with first irrigation. In rainfed conditions, apply 33 kg of urea and 50 kg of single superphosphate per acre by drilling at the time of sowing.

Celery:

— Start transplanting celery crop at a spacing of 45 x 25 cm. Use 65-70 days old seedlings. At the time of transplanting, apply 90 kg of urea and 100 kg of superphosphate per acre.

Vegetables

Carrot, radish and turnip:

Apply 15 tonnes of farmyard manure per acre and mix it with the soil by ploughing about 10 days before sowing these crops. Drill 55 kg of urea, 75 kg of superphosphate per acre at the time of sowing. For carrot, 50 kg muriate of potash per acre should also be added.

Root crops:

Start sowing English varieties of radish (Japanese White), turnip (Golden Ball, Snow Ball, Purple Top, White Globe) and carrot (Nantes).

Irrigate these crops only when it is must, otherwise excessive vegetative growth will lend to hairy, cracked, deformed, small and forked roots.

(Progressive Farming, PAU).