 |
|
|
Solar (PV) pumps — common
pitfalls Solan, emerging mushroom city of
India Need to professionalise farm
education Farm operations for
October Plan to modernise rice mills
|
|
|
Solar (PV) pumps — common
pitfalls THE Punjab Government has decided to install 500 PV-solar tubewells for meeting irrigation needs. Each solar pump will be of 5-hp capacity and estimated to cost Rs 5 lakh. These pumps will be supplied to the farmers at 90 per cent subsidy i.e. the farmers will have to pay Rs 50,000 only. In the first phase Fatehgarh Sahib district will be covered and for the purpose a provision of Rs 22.5 crore has been made. PV-based schemes usually face certain snags which need to be avoided. This venture also has the difficult task to prove itself to be viable in view of the “free electricity” for farmer’s tubewells being made available currently. Output of PV arrays: It has been found that in actual practice the output given by PV arrays is nearly half of that is claimed by the suppliers. In this regard the case of the Kalyanpur PV plant of Aligarh (UP) is cited. This plant with 100 KW capacity, completed at a cost of Rs 4.75 crore, was launched in 1995 with a lot of fanfare. Soon after commissioning, the power plant developed snags and the scheme is opening at 48 per cent output i.e. delivering only 48 KW. Punjab located at 32° N has a good solar irradiance level and sunshine hours exceeding 3000 hours in a year holds a promise for tapping this eco-friendly source of power. The amount of annual irradiance (watts per square metre) ranges from 130 to 160 and the annual insolation level of around 1400 Kwh/m2. Quality of power available: The PV arrays produce DC power at 60 volts and is variable in output due to the sunshine level obtained. One array is rated around 300 to 360 wp which is considered sufficient to a run a ½-hp pump. The power obtained cannot be used directly and requires use of an intelligent device to obtain the optimum output and an invertor if the motor to be used is of AC type. The intelligent devices available are MPC (Maximum power controller) or MPPT (maximum power point tracker). The devices sample output every 30 milli-second intervals, compare with previous value and communicates the required correction. The PV arrays are usually mounted on a simple metallic frame (of galvanised steel or aluminium) and have arrangement of orienting the array to face the sun to have the maximum irradiance. Generally the arrays are mounted on movable trolleys and are adjusted three or four times during the day. The dust-free atmosphere and low temperature lead to higher efficiencies of the solar cell. In the case of “silicon cells”, for every 1 degree rise in temperature above 28°C, there is drop in efficiency by 1 per cent. The attainable efficiency of monocrystalline cells is 18 per cent of the impinging solar energy. Motors: If a DC motor is connected directly to an PV array, the system will operate at a point where current and voltage characteristics of motor intersect the I/V curve for the prevailing level of irradiance. Since this does not provide the optimum point, so an electric power conditioner is necessary so that the optimum value and enhanced system efficiency is obtained. For better output DC motors having brushed commutators and permanent magnets are used. The brushes may have the design life of 2000 to 3000 hours. But the most common problem with brushed DC motors is deposition of carbon on commutators resulting in a breakdown. Now brushless DC motors are available with permanent magnet and electronically switched field windings. Field studies have shown that shunt motors give good matching to solar arrays under shadow tolerance. The efficiency of commercially available DC motors of brushed type reach peak value of 85 per cent, but improvement in the system needs to be obtained using more efficient motors so that the system becomes cost-effective. Pumps generally used with the PV system are surface mounted centrifugal pumps or vertical centrifugal pumps coupled to a submersible DC motor. Of the two alternatives, the submersible pump system is preferable as it eliminates the suction pipe and the foot-valve, which are the source of low efficiency. Such units are made leak-proof by provision of a silicon-carbide seal. For lifts up to 5 to 6 m, single stage centrifugal pumps, with a special provision of “self-priming” are used which have the capability of coping with frequent “on/off” switching due to variations in solar irradiance. The centrifugal pumps have been found to be more reliable to operate in submerged or floating pump set system which are kept in position with floating bouy in open wells and such systems do not need “priming”. Field trials: In the 1980’s
twenty-five different types of PV solar pumps were tried in Punjab (Pakistan). The PV arrays and floating motor pump systems were handed over to farmers for operation in their fields. The trial covered three years’ period. The sets comprised 800 watts trolley mounted PV arrays and floating motor pump systems capable of giving peak performance of delivering 2.5 liters of water/second through a static lift 5 m. The farmers were required to adjust the arrays two to three times a day so as to obtain the maximum output. The farmers could irrigate about 1.2 hectares (ha) during the Kharif and 2 ha during rabi season. The maximum quantity of water pumped in a day amounted to 100 m3 and 65 m3 in summer and winter seasons, respectively. No difficulty was experienced by the farmers in operating the sets which include MPPT of power conditioning equipment and gave about 3000 hours of trouble-free service. Compared to the above, the trial at the IPRI (Irrigation and Power Research Institute), Amritsar, on the 300-360 wp panel, DC motor pump (centrifugal) set with an “on/off” switch indicated that the yield did not exceed 50 per cent of the targeted value. Its motor often got overloaded and burnt. |
|
Solan, emerging mushroom city of
India THE first serious effort on indoor cultivation of white button mushroom in India was made in the early sixties in Solan (Himachal Pradesh), which led to the launch of a United Nations Development project and posting of one food and agricultural expert at Solan. The pioneering research work of the Himachal Pradesh Krishi Vishvavidyalaya on its Agriculture Collage campus at Chambaghat (Solan) laid the foundation for mushroom research in the country. Later, important contributions came from other areas of the country also. However, a significant landmark in the history of mushroom research and development was the establishment of the National Centre for Mushroom Research and Training (NCMRT) under the auspices of the Indian Council of Agricultural Research (ICAR), New Delhi. It was sanctioned under the Sixth Five Year Plan. The original mandate of the Centre was to conduct basic, strategic and applied research for developing technologies to enhance productivity and utilisation of all edible mushroom to act as a national repository of scientific information on edible mushroom, to provide scientific leadership and coordination network research to act as a centre for training in modern research methodologies and technology upgradation for the production of mushroom and to provide consultancy in mushroom research and development. However, in view of the recent spurt in the production and trade of mushroom in India and the post-GATT world scenario, the mandate is proposed to be revised. It shall also promote human resource development transfer of technology and shall provide technical support to the mushroom industry as well as rural masses for poverty alleviation. Keeping in view the pioneering work undertaken in mushroom research and development, the NCMRT earned Solan district town the honour of being reorganised as the mushroom city of India. It was formally inaugurated on Sept. 10, 1997, by the then Chief Minister of Himachal Pradesh, Mr Virbhadra Singh. Mushroom is a simple form of life known as fungus. It grows on dead organic matter or parasitically or symbiotically with other living organisms. The edible part constitutes the fruit body. More than 2,000 species of fungi are reported to be edible throughout the world. In India about 200 of these are available. Eight have been cultivated so far. Mushroom is frequently mentioned as alternative resources for food. The modern mushroom culture produces more proteins per unit area of land than by any other form of agriculture. Its use as food is probably as old as cultivation itself. But the nutritive value of mushroom was recognised only in recent times. Mushroom is richer in protein as compared to cereals, pulses, fruits and vegetables on dry weight basis. The efficiency with which mushroom converts carbohydrates into protein is about 65 percent in comparison to about 20 percent in pork and 45 percent in beef. Its proteins have 60 to 70 percent digestibility and it contains all the essential amino acids. In addition to protein (3.7 per cent), mushroom also contains carbohydrates (2.4 percent), fat (0.4 per cent), minerals (0.6 percent) and water (91 per cent) on fresh weight basis. It also contains vitamins B, C, D and K and minerals like calcium, phosphorus, potassium, iron and copper. Mushroom is completely devoid of starch and hence constitutes a good item in the diet of diabetic persons. Beside, mushroom contains a high fiber content which is a usefully constituent of our diet. The vitamins are well retained during cooking, canning, drying and freezing. Reports indicate its potential as life-saving drugs antibiotics and biologically active substance. It has various industrial uses. Mushroom has been cultivated successfully at different places in India. It requires 30 to 35°C temperature for growth. The best season for growing this mushroom in Punjab, Haryana Uttar Pradesh, Madhya Pradesh, Tamil Nadu and Maharashtra is from April to October. The Humidity should be 50 percent. One crop cycle takes 30 to 35 days. Its cultivation does not require mush skill, care and investment. Mushroom is highly perishable and should be marketed and consumed as soon as possible after harvest. Because of its very high moisture content (90-92 percent), it loses weight very fast, hence not suited for storage. Mushroom can grow on a wide variety of agricultural wastes, which are easily available and are cheap, its cost of production is therefore, less. The cost of production worked out by different sources ranges from Rs 8to Rs 15 per kg. It is sold at Rs 20 to Rs 25 per kg. It can be stored in polythene bags at 5°C then the shelf life can be extended to seven days. Storage at high temperature result in browning and rotting. |
|
Need to professionalise farm
education PRACTICALLY, a profession is an occupation or calling which makes necessary scientific or artistic learning. Professional education is expected to be collaborated with employment, to be job-oriented, to provide one with specialised education and training for a livelihood. The rise of corporate businesses in the past few years has created vast opportunities for employment and service for most professionals. Engineering, computers, finance and accounts and business management are some of the courses that have a basic commercial orientation. There is a recent phenomenal growth in management diplomas related to different professional fields to cater to job opportunities available in the business sector. Agriculture became a professional stream through evolution of applied biological sciences. In India, training and teaching in agriculture started in 1905 with the inception of Imperial (now Indian) Agricultural Research Institute of Pusa, Bihar (shifted to New Delhi in 1936) and simultaneous opening of six agricultural colleges at Coimbatore, Layallpur (now in Pakistan), Kanpur, Nagpur, Pune and Sabour. The Imperial (now India) Council of Agricultural Research came into being in 1929 to promote and coordinate agricultural research and higher education. Since then, rapid strides in the field of agro-research, education and development have resulted in establishing several agricultural universities. Today, there are 27 state agricultural universities, one central agricultural university and 35 agricultural colleges within general universities. They offer under undergraduate and postgraduate programmes in several fields. Barring veterinarians, most other agricultural professionals do not individually practise professional or technical skills like medical doctors or lawyers, nor have they acquired commercial and business orientation of other professions. The educational system and the employment opportunities in our country have slotted agriculture as an applied science but kept it away from realising its true potential as a profession. Employment opportunities in the public research and extension systems have dominated curricula in the agricultural universities for long time. The accent has been on scientific sub-disciplines and extension or communication methods. Even at the postgraduation level, greater emphasis is laid on research rather than applied management. It is this lack of managerial orientation in the professional courses that comes in the way of agriculture graduates or postgraduates from getting even middle level management positions in the private, commercial or corporate sectors in agricultural input marketing or agro-output processing industries. Other professionals from the fields of marketing, finance, production, etc. are cornering management positions, while agriculture graduates are pushed down the ladder as field functionaries to make use of theirs limited technical knowledge. New development in science and technology, growing international trade and competition in agriculture, changing consumer demands and modification of production and processing patterns, and growing concern to issues of environmental control and sustainability are the changes necessitating the institutions of agriculture education to reconsider and modify their objectives, programmes and management practices. An MBA degree in agriculture introduced in the 1992-93 at the CCS Haryana Agricultural University, Hisar, has made the study practically oriented. The programme encourages the students to go in for the agro-industry sector, agro-business sector and agro-based self employment. The IIM Ahmedabad, also offers management education in the field of agriculture. |
|
Vegetable crops Cole crops: Start transplanting cabbage, mid-season cauliflower and knol khol. Keep line and plant-to-plant spacings at 45x30 cm for cabbage and cauliflower, and 30x 20 cm for knol khol. Plant cauliflower on ridges and others on flat beds. Pea: — Start sowing mid season pea for green pods and the Mithi Phali variety from middle of October. Use the Punjab-87, Punjab-88 or Bonneville varieties. Use 30 kg of seed per acre. Drill seed in line at 45 cm apart. — Wilt and stemfly are serious problems of field pea, hence avoid early sowing in badly infested area. Treat the seed for the control of wilt and stemfly with Bavistin @ 1 g and 5 ml of Chlorpyriphos mixed in water for 1 kg of seed. — Weeds can effectively be controlled with the use of Afalon 50 WP (Linuron) @500 g/acre or Stomp 30 EC @ 1 litre/acre as pre-emergence application i.e. within two days of sowing. Use 150-200 litres of water for uniform spray and use flat fan/flood zet nozzle only for this purpose. Potato:
— Complete sowing of autumn potato crop in the first fortnight of October, particularly for seed production purpose. Use healthy seed tubers. — Sow potato after applying 20 tonnes of farmyard manure, 82 kg of urea, 155 kg of superphosphate and 80 kg of muriate of potash per acre. farmyard manure should be applied about 10 days before planting potato, whereas fertiliser should be applied at the time of sowing, preferably mix with soil to avoid injury to tubers. Higher doses of nutrients can be applied if soil test shows low to very low status of these nutrients. — For weed control, use Atrataf 50 WP/Atrazine @ 200 g/acre or Isoproturon 75 WP @ 500 g/acre or Stomp 30 EC @ 1 litre/acre or Sencor 70 WP (Metribuzin) @ 200 g/acre as per-emergence or spray Gramoxon @ 500-750 ml/acre up to 5-10 per cent emergence of the potato crop and complete germination of weeds. Do not use Atrataf in those fields where succeeding crop is to be a cucurbit. — For the control of later blight, use selected healthy tubers for sowing. Follow high ridge method to avoid tuber infection. — Disinfect the seed tubers in 0.5 per cent solution of Agallol or 0.25 per cent Emisan/Aretan by dipping for 10 minutes to control black scarf and common scab. Avoid sowing of potato in fields with high incidence of
common scab. Keep the high incidence of common scab. Keep the soil wet at tuberisation to minimise the scab infection. Follow high ridge culture to avoid tuber infection. If there is a heavy shower in second or third week of October, protect the crop immediately by spraying Indofil M-45 @ 500-700 g/acre. Potato should not be grown in common scab-infested fields. Onion:
— On 15-20 cm high beds, sow 4 kg of seed either of the Punjab Red Round or Punjab Naroya, Punjab Selection (red skinned) or Punjab-48 or PDW-1 (white skinned) variety to raise seedlings for transplanting in one acre. Keep the ratio of nursery bed and field area to 1:20 (8 marlas: 1 acre). — Irrigate kharif planted crop once a week. Plant bulbs for seed production. Tomato: — Start sowing nursery of tomato. Use 200 to 250 g seed of the recommended varieties in one marla (25 m) bed area to grow seedlings for an acre. Show TH-2312, TH-802, S-12, Punjab Tropic and Punjab NR-7 for local markets and kitchen gardens. Punjab Kesri for medium distance markets and Punjab Chhuhara for long distance marketing and processing purpose. For planting in nematode infected fields, sow nursery of only the resistant variety Punjab NR-7 or hybrid TH-2312. Root crops: — Apply 50 kg of urea, 155 kg of superphosphate per acre for radish, turnip and carrot. Carrot also requires 40 kg of muriate of potash per acre. Sow the Punjab Safed, L-1 and Sel. 21, Sel. 233 and No. 29 varieties of radish, turnip and carrot using 4, 2 and 4 kg of seed per acre, respectively. Sowing on 45 cm ridges is better than in flat planting because of high yield, easy harvesting, better root shape and richness in nutrients. Leafy vegetables:
— Sow palak, methi, lettuce and Chinese cabbage by using 5 kg of seed for direct sowing and 200 and 250 g for raising nursery respectively. |
|
 |
Plan to modernise rice mills THE Food Ministry has planned to ensure financial assistance to rice millers to enable them to undertake technology upgradation to avoid foodgrains loss during processing of paddy. A project has been prepared to upgrade rice mills in the country for which loans will be made available. Currently, the average rice yield from paddy is 67 per cent — much below the international standard of 71.33 per cent — which results in the huge losses. The technology upgradation of rice mills will help achieve 72.73 per cent yield. Right now, rice mills are in a poor shape as a result of which more broken rice is being obtained from paddy. According to the ministry’s proposal, the credit line would be extended to the millers, especially in the states like Andhra Pradesh, Madhya Pradesh, Punjab and Uttar Pradesh. In another development, the Food Ministry has decided to increase the storage space for foodgrains. The government is also working on the concept of improving bulk handling and transportation of foodgrains, food and civil supplies.
|
