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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Definition of irrigation:, Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , • Dicthnary “the supply of water to land or crops to, help growth, typically by means of channels.”, • Irrigation is the artificial application of water to soil, for the purpose of crop production. Irrigation water is, supplied to supplement the water available from rainfall, and contribution to soil moisture from ground water. In, addition; irrigation can also be applied for leaching of, soluble salts from saline soils, to regulate soil-plant, temperature, field preparation etc.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Objectives of irrigation, • To increase productivity (the crop yield per unit, area). The productivity of the crop increase from, 30-60% due to irrigation., • To expand area under cropping., • To increase cropping intensity., • To minimize induce fluctuation in food production.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Principals of irrigation, •, •, •, •, , Maximization of water use efficiency (WUE)., Irrigate upto field capacity (FC) except rice., Standing water even for an hour except rice., Application efficiency should be maximum, (leveling, bunding, and special shaping)., • Irrigation water should be soaked the root zone, and water management zone by mulching and, weed control., • Irrigation interval and intensity should be based on, soil, crop cultivation and environment.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Irrigation requirement, The net irrigation requirement is the depth of, irrigation water exclusive of precipitation, carry over, soil moisture or ground water contribution or other, gains in soil moisture; that is required for crop, production. It is the amount of irrigation water, required to bring the soil moisture level in the, effective root zone to field capacity. Thus it is the, difference between the field capacity and the soil, moisture content in the root zone before starting, irrigation.
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System of irrigation, ▪ The selection of systems of irrigation depends upon, several factors viz. type of crop to be grown,, topography and texture of the soil, climatic conditions,, water resource and economic conditions of the, cultivator., ▪ The irrigation systems are divided into following, groups:, a) Surface irrigation system, b) Sub surface irrigation system, c) Drip irrigation system, d) Sprinkler irrigation system
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A) Surface irrigation system, ▪ Water is applied to the soil surface from a channel, located at the uppermost of the field., ▪ Water may be distributed to the crops in controlled, flooding and uncontrolled flooding., ▪ Water is applied on the soil depends upon topography,, texture, type of crop grown, quality and quantity of, available water, source of available water and energy and, labour required for irrigation.
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Surface irrigation
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Methods of surface irrigation, 1) Uncontrolled flooding, ▪ This is most primitive and wasteful method of, irrigation., ▪ It is followed in areas where unlimited water is, available and a vast area like pasture is to be, irrigated., ▪ In this method water is let into the field from the, higher gradient and spread slowly all over the, cropped area depending upon the slope.
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Limitation of uncontrolled flooding, • Greater loss of water and nutrients, • More soil erosion, • Depth of irrigation varies from place to place, due to varied topography., • Greater percolation in certain pockets.
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2) Controlled flooding, ▪ In this method of irrigation field plots, which, are to be irrigated are divided into several plots, convenient sizes of more or less even surface., ▪ The water is let into the field through main and, sub channels for irrigation plot one after, another.
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Control flooding
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A) Check basin method, ▪ It is applied in those areas where small stream of water is, available, ground is nicely leveled and the crop needs a, careful distribution of water., ▪ Bunds are constructed around the area forming basin within, which the irrigation water can be controlled., ▪ The water is conveyed through main channel and branch, channels which used to connect two consecutive parallel rows, of beds or basins., ▪ Rectangular or square beds of 10-100 m2 areas are prepared., , ▪ Onion, garlic; rice can be irrigated by this method.
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Merits, ▪ Different kinds of crops can be grown in sequence in the, same field without making major changes in design,, layout or operating procedure., ▪ Useful when leaching is required to remove salts from, soil profiles., ▪ Results in high water application and distribution, efficiency.
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Demerits, ▪ Very expensive as preparation of ridges for making channels., , ▪ Fairly large area is occupied by ridges and channels which, remain uncropped., ▪ Ridges interfere in movement of animal drawn or tractor, drawn implements for interculture or harvesting of the crops., ▪ Precise land grading and shaping are required., ▪ This method is not suitable for irrigated crops which are, sensitive to wet soil conditions around the stem of plants.
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B) Border strip method, • The field is divided into a number of long parallel strips called, borders that are separated by two ridges., • It is suitable in areas having a slope of 0.5-1.0%., , • The width of strip may be 3-15 m and length may be 50-300, m, which depends upon type of soil and extent of slope, exceeds 1% slope the contour borders are prepared., • The border strip method is suitable for irrigating all close, growing crops like wheat, barley, fodder crops and legumes.
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Merits, • Border ridges are easily constructed with simple farm tools., , • Labour requirement is greatly reduced., • Uniform distribution of water is maintained with higher, application efficiency., • Operation system is easy and simple., • Surface drainage can be easily made from the cross ridges., • This method is more suitable to the soils having moderately, low to moderately high infiltration rates.
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Demerits, • It is not suitable for those crops which require water, stagnation through out their cropping period e.g. rice, jute, etc., • This method is not suitable in sloppy and undulated land, areas and having coarse sandy soils (having high, infiltration rates)., • It is also not well suited to soils having very low, infiltration rates.
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C) Furrow irrigation method, ▪ It is used for those crops which are sensitive to saturated, conditions at the root zone, these are root and tuber crops., ▪ It is adopted for irrigated row crops where furrow made, between the crop plant during the land preparation and, planting., ▪ The crop is sown on the ridges and the irrigation water is, applied in the furrow so that most of the roots remain above, the saturation zone and there is no soil compaction.
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Furrow method of irrigation
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▪ Field is divided into ridge and furrows along or across the, slope and the furrows are connected with main channels., ▪ Sometimes ‘V’ shaped furrows are prepared along the slope, of the land which are called corrugated or corrugation, method of irrigation.
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Merits, • Water in the furrows contacts only one half to one fifth, of land surface, thereby reducing puddling and crusting, of the soil, and evaporation losses., • Earlier cultivation is possible which is a distinct, advantage in heavy soils., • The labour requirements in land preparation and, irrigation is greatly reduced., • No wastage of land in field ditches.
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D) Ring basin method of irrigation, ▪ Applied to widely spaced crops where limited stream of, water is available for irrigation., ▪ A ring is prepared around each plant and each row of rings is, connected with each other through main channel which is, prepared at the end of the row of rings., , ▪ Rings may smaller during the early stage but the size, increases as the plant grows.
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Ring basin method
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B) Sub surface method of irrigation, ▪ The water is applied below the ground surface by, maintaining an artificial water table at some depth, depending upon the soil texture and the depth of the plant, roots., ▪ Water reaches the plant roots through open ditches or, underline pipelines called tile drains or mole drains., ▪ The water application system consists of field supply, channels or trenches suitably spaced to cover the field, adequately and drainage ditches for the disposal of excess, water.
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Sub surface drip irrigation
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Merits, i) High water use efficiency., ii) Needs least labour., iii) Low evaporation loss through ground surface., , Demerits, i) Very expensive, ii) A slight negligence in applying water may, lead to water logging in root zone, iii) Water having a high salt contain can not be, used.
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C) Drip irrigation method, • Also called trickle irrigation., • Applying water drop by drop to the individual plant, by minimizing conventional losses such as, percolation, runoff and soil water evaporation., • Irrigation is done by small diameter plastic lateral, lines with drippers at desire spacing., • Applies water slowly to the soil moisture with the, desired range of plant growth., • This method of irrigation is generally used in row, crops in orchard.
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Drip irrigation
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Merits, ▪ Drip irrigation method can achieve a 90% or more, application efficiency, which can hardly be achieved, by any other methods of irrigation., ▪ The method reduces salt concentration in the root, zone when irrigated with poor ground water., ▪ Soluble fertilizers and pesticides can also be applied, through this method of irrigation.
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Demerits, ▪ High initial cost, ▪ The requirement that the water must be relatively, clear, otherwise clogging problems may occur., ▪ Poor water distribution efficiency when a low, pressure system is installed on steep slopes or uneven, land.
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D) Sprinkler irrigation method, ▪ It is also called overhead system of irrigation, ▪ Water is made to spray through nozzle fitted pipe over, the foliage of the crop plants as artificial rain., ▪ Pressure is generated by pumps and IC engine and water, is sprayed through nozzle., ▪ This method is used for all crops in any soil condition, except in the soils having very low infiltration capacity., ▪ This method is categorized as:, a) Rotating head system, b) Perforated system.
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Sprinkler method of irrigation
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Sprinkler method of irrigation
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Merits, ▪ Better method for ground having uneven, topography or land leveling is not essential for, sprinkler irrigation., ▪ Better for light textured soils., ▪ Soluble fertilizer, insecticides and herbicides can, also be sprayed easily through this system., ▪ Sprinkler irrigation can be used for almost all, crops (except rice and jute), ▪ Small streams of irrigation can be used, efficiently.
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Demerits, ▪ Sprinkler irrigation is 2-2.5 times costlier than surface, irrigation for the same depth of water application., ▪ Clay soils that have a slow intake rate coupled with hot,, dry windy areas are not suitable for sprinkler irrigation., ▪ Sprinkling water may cause fungal disease, wash pollen, and reduce fruit set., ▪ If the water containing large quantity of dissolved salts,, this method may not be useful., , ▪ Power requirement is high.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Irrigation scheduling, Irrigation scheduling is defined as the determination of the, period when to irrigate and how much to irrigate for, optimal crop production., (Handbook of Agriculture by ICAR), , ▪ There are several approaches for scheduling irrigation, based on crops, soil atmosphere and plant water, relations. The most important approaches are:, 1. Soil moisture depletion approach, 2. Physical stage or critical stage approach., 3. Cane Evaporimeter approach, 4. Irrigation scheduling based on calculations.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , 1. Soil moisture depletion approach, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ▪ The available soil moisture in the root zone is a good, criteria for scheduling irrigation., ▪ For crops like maize, wheat etc. scheduling irrigation, at 25% depletion of available soil moisture is, adequate., ▪ For drought resistant crops like sorghum, pearlmillet,, finger millet, cotton etc. it is coefficient to irrigate at, 50% depletion of available soil moisture.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Critical stages of water requirements, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Crop, Rice, , Physiological/ critical stages, Tillering, flowering, milk and dough, , Wheat, , Crown root initiation (CRI), tillering, milking and, dough, Maize, Early vegetative growth, tasseling, silking and, dough., Sorghum, Seedling, flowering and dough, Barley, Early vegetative, flowering and dough, Oat, Ear emergence, Finger millet Flowering, grain formation, Soybean, Early seedling, flowering, pod development, Potato, Sugarcane, , Stolonization, tuberization and bulking, Emergence, tiller initiation, tillering, elongation
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Instruments to measure soil moisture, Available soil moisture can be measured from, the following instruments., i) Neutron moisture meter, ii) Electrical resistance, iii) Tensiometer
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , 3. Irrigation scheduling based on calculations, (IW/CPE Ratio approach), ▪ IW/CPE approach a known amount of irrigation water (IW), is applied when cumulative pan evaporation (CPE) reaches, a predetermined level., ▪ The amount of water given at each irrigation ranges from 46 cm, the most common being 5 cm of irrigation., ▪ Scheduling irrigation at an IW/CPE ratio of 1.0 with 5 cm, of irrigation water means 5 cm of irrigation water is applied, when the CPE reaches 5 cm., , ▪ Generally irrigation is scheduled at 0.75-0.8 ratio with 5 cm, of irrigation water.
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Madan Bhandari Memorial Academy Nepal, Calculate cumulative pan evaporation, required for scheduling, irrigation at 0.5, 0.6 and 0.75 and 0.8 with 5 cm of irrigation, water., , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Solution, Cumulative pan evaporation at IW/CPE ratio of 0.5 = IW/CPE = 0.5, 5 = 0.5, CPE, CPE x 0.5 = 5, CPE = 5 = 50 = 10 cm, 0.5 5, Therefore irrigation of 5 cm is given when CPE is 10 cm., CPE at 0.6 ratio = 5 = 8.33 cm, 0.6, CPE at 0.75 ratio = 5 = 6.66 cm, 0.75, CPE at 0.8 ratio = 5 = 6.25 cm, 0.8, , In IW/CPE ratio approach, irrigation can also be scheduled at fixed level of CPE by, varying amount of irrigation water.
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Grain yield and water expense efficiency of maize as, affected by different irrigation schedules, Cobs/plant, , 100-grain, weight (g), , Grain, yield, (q/ha), , Water Use, (cm), , Water Use, efficiency, (kg/ha-cm), , 0, , 0.84, , 17.3, , 13, , 12.9, , 105, , 0.5, , 0.92, , 19.2, , 22, , 24.6, , 89, , 0.75, , 1.01, , 20.3, , 38, , 30.4, , 126, , 1.00, , 1.04, , 19.7, , 40, , 36.7, , 110, , CD, (p=0.05), , 0.06, , 0.7, , 03, , _, , _, , IW/CPE, ratio, , Khan et al (1996),, Indian J Agric Sci 66(5): 272-75
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Influence of irrigation scheduling on plant height,, yield attributes and yield of maize, Treatments, , Plant height, (cm), , Number of, grains /cob, , 100 grain, weight, , Grain yield, (q/ha), , 0.50 IW/CPE, (4), , 189.53, , 279.23, , 23.81, , 38.98, , 0.75 IW/CPE, (7), , 199.10, , 339.40, , 25.95, , 46.80, , CD (p=0.05), , 0.35, , 2.53, , 0.08, , 0.38, , Selvaraju and Iruthayaraj (1994),, Madras Agric J 81(8): 418-20
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , 4. Cane Evaporimeter approach, • In has small cans of one liter capacity (14.3 cm height and, 10 cm diameter) are used to indicate evaporation from the, cropped field., • When irrigation is given bringing the soil to field capacity,, the cane is filled up with water to pointer level., • Evaporation from cane is directly related to crop, evapotranspiration., • In IW/CPE approach, a known amount of irrigation water is, applied when cumulative pan evaporation (CPE) reaches a, predetermined level. The amount of water given at, each irrigation ranges from 4 to 6 cm. The most common, being 5 cmirrigation. Scheduling irrigation at an, IW/CPE ratio of 1.0 with 5 cm.
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Madan Bhandari Memorial Academy Nepal, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , (Affiliated to CTEVT)
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Drainage, Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ❑ Adverse effect of water logging., ❑ Types of drainage:, ✓ Surface drainage (open ditch drainage, random, field ditch drainage, land smoothening,, bedding/dead furrow), ✓ Sub-surface drainage, ✓ Bio-drainage (Biological)
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Drainage, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ▪ Drainage is the removal of excess water either from, agricultural land or barren land., ▪ Agricultural drainage is the provision of a suitable, system for the removal of excessive irrigation of rain, water from the land surface so as to provide suitable, soil conditions for better plant growth., , ▪ Excess water becomes a problem when it interferes, with tillage, land preparation, development of plants, and harvesting operation.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Objectives of drainage, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ▪ To remove the excess water from the soil for, improving the productive capacity of the soil., ▪ To improve the soil structure, increase in depth of, plant rooting zone., ▪ To improve the organic matter decay, nitrification and, reduce erosion., ▪ Removal of salts from the saline soil in irrigated land.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Principles of drainage, ▪ The main drainage lines should follow the lines of, natural drainage., ▪ Laterals should be laid along lines of greatest slope., ▪ Where possible, long parallel laterals should be used., ▪ Drainage lines should be made straight or with, gradual errors., ▪ The outlet should be protected from erosion., ▪ In heavy clay soils of tops surface drainage is, preferred.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Benefits of drainage, Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ▪ Drainage facilitates early ploughing and planting., ▪ Helps to increase root zone depth and decrease erosion., , ▪ Leaches excess salt from soil., ▪ Improves soil structure and infiltration capacity of soil., , ▪ Maintains temperature., ▪ It helps the soil to favour growth of soil bacteria.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Effect of poor drainage, ▪ The excess water affects on soil aeration, soil, temperature, biological activity, soil chemistry and, overall problems of land and crop management., • Poor aeration causes decomposition of organic matter, producing hydrogen sulphide gas that is toxic to the, roots., , • The change in balance between O2 and CO2 affect the, growth and longevity of the disease organisms eg., Cereal root rot and fusarium root rot of sugarbeet., • Soil structure is adversely affected.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , • Poor aeration may accumulate sufficiently high, concentration of reduced iron and manganese, causing toxicity to the roots., • Denitrification occurs rapidly in saturated soil, and reduction in number of nitrifying organisms., • High moisture level reduced the uptake of plant, nutrient.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Types of drainage system, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , 1) Surface drainage system, ▪ The process of removing the excess water from the land, surface is known as surface drainage., ▪ Surface drainage is the orderly removal of excess water, from the surface of the land through improved lateral, channels.
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Madan Bhandari Memorial Academy Nepal, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , (Affiliated to CTEVT)
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A) Land Smoothening, ▪ Land smoothening some times called land forming or, grading is the operation of producing a plane land, surface with a uniform slope., ▪ This practice is usually necessary to supplement the, field surface drainage or irrigation., ▪ Land smoothening is generally accomplished in two, operations rough grading and smoothing or finishing., ▪ Rough grading is done with a bulldozer scraper while, final smoothing is done by a flat leveler or grader.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , B) Open ditch system, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ▪ It consist of field ditches which collect surface water, directly and employ into outlet ditches., ▪ The outlet ditches collect water from field ditches.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , C) Random Ditch System, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , ▪ This is suitable for land with regular topography., ▪ Surface water from ponded areas may be removed by, random field ditches or surface drains., ▪ Random field ditches are shallow ditches with flat side, slopes that can be crossed with farm machinery.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , D) Bedding System, • The bedding system of surface drainage is designed,, constructed and maintained so that surface water drains, laterally from stripes of lands into dead furrows then, into collection ditches and finally into an outlet., • The dead furrow is known as a bed.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , 2) Sub surface drainage, • If excess water saturates the pore space of soil, the, process of its removal by downward flow through the, soil is known as sub surface drainage., , • Sub surface drains are underground artificial channels, through which excess water may flow to a suitable, outlet.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , Merits, ▪ Land is not wasted and there is no interference to, farming operations by subsurface drainage., ▪ This system requires less maintenance., , Demerits, ▪ Require high initial investment., ▪ Inlets and outlets should be maintained properly.
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Madan Bhandari Memorial Academy Nepal, , (Affiliated to CTEVT), , Methods of sub-surface drainage system, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , 1) Pipe or tile drainage:, Continuous line of pipe or tiles laid at specified spacing, depth, and grade remove excess water from the soil profile. Pipe or, tiles should be placed at 60 to 70 cm below the soil surface., , 2) Vertical or drainage well:, Water table can also be lowered by drainage well. A deep and, uniform soil without any obstruction for downward movement, of water is ideal for drainage well., , 3) Mole drains:, Mole drains are cylindrical channels formed at a desired depth, in the soil profile. Water entering throughout the mole drains is, guided to the outlet.
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Madan Bhandari Memorial Academy Nepal, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , (Affiliated to CTEVT)
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Madan Bhandari Memorial Academy Nepal, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , (Affiliated to CTEVT)
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Madan Bhandari Memorial Academy Nepal, , 3. Biological drainage (bio-drainage):, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , (Affiliated to CTEVT), , Biological drainage (bio-drainage) is a natural vegetable cover,, wood species and agricultural crops with high transpiration capacity., During their life activity, they absorb large quantity of soil moisture,, and as a result groundwater table lowers. Example Eucalyptus,, Alpha alpha etc., Alfalfa, willow, poplar and other crops and wood species serve as, bio-drainage. For example, during the growing season alfalfa, consumes 4-20 ths m3/ha of water (depending on age, depth of, groundwater level, grain-size distribution, thickness of sowing, and, other conditions). At that, the share of groundwater in the total flow, varies from 0 to 78%. In summer, during the period of intensive, absorption of moisture by plants groundwater table under alfalfa, fields is as a rule lower by 50-70 cm than that under cotton fields., Alfalfa has also high salinity resistance: it consumes saline, groundwater with total salt content up to 5 g/l.
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Madan Bhandari Memorial Academy Nepal, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , Bio-drainage by Eucalyptus, , (Affiliated to CTEVT)
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Madan Bhandari Memorial Academy Nepal, , Principles and Practices of Agronomy by Govinda Raj Sedai, Agronomist, , A, G, R, O, N, O, M, Y, , By, G., R., S, E, D, A, i, , (Affiliated to CTEVT)
