Indian Journal of Soil Conservation
Year : 2008, Volume : 36, Issue : 1
First page : ( 24) Last page : ( 30)
Print ISSN : 0970-3349.

Development of crop coefficient model of potato under plant-furrow treatment

Panigrahi B.

Directorate of Research, Orissa University of Agriculture & Technology, Bhubaneswar-751003, Orissa.

Received:  May,  2007; Revised:  February,  2008; Revised:  April,  2008; Accepted:  April,  2008.

Abstract

Crop coefficient (K_c) plays vital role in computation of actual evapotranspiration of crops and thus, is very helpful for regional irrigation planning and management. Both the irrigation scheduling and irrigation strategies depend upon the values of K_c of crops. In the present study, field experiments were conducted to study the effects of plant-furrow treatments and levels of irrigation on finding K_c of potato (Solanum tuberosum L.). The two plant-furrow treatments were F₁-furrow with single row of planting in each ridge with 45 cm distance between adjacent ridges, and F₂-furrows with double row of planting spaced 30 cm apart in each ridge with 60 cm distance between adjacent ridges. The two levels of irrigation (LOI) were I₁-0.9 IW/CPE and I₂-1.2 IW/CPE, where IW is irrigation water of 5 cm and CPE is cumulative pan evaporation. The average daily crop evapotranspiration was found in the range of 1.1 to 3.5 mm and 1.2 to 4.0 mm for treatment F₁ at irrigation levels of I₁ and I₂, respectively. For treatment F₂, it was from 1.1 to 3.6 mm and 1.2 to 4.1 mm at irrigation levels of I₁ and I₂, respectively. Regression based models for estimating the crop coefficients on daily basis were developed. The models predicted potato crop coefficients and were compared with the FAO-24 reported crop coefficients. At lower irrigation level, the coefficients agreed well for initial and mid season stage but differed at the maturity stage. The reverse trend was marked for higher irrigation level. The developed model can be used in estimation of daily crop coefficient which will help in computing the actual crop evapotranspiration demand for better irrigation scheduling on regional basis.

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Keywords

Crop coefficient, Evapotranspiration, Plant-furrow treatment, Potato, Regression model.

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