References
[1] Sankaran, S. and Mani, V. S. (1972) Effect of weed growth on nutrient uptake and seed yield of sorghum. Indian Journal of Weed Science, 4.
[2] Hay, J .R. (1974) Gain to the grower from weed science. Weed Science, 22
[3] Rao, V. S. (1983) Principles of weed science. IBH Publishing Company, Oxford, UK. Rempel E, 1989.
[4] Savary, S.L., Willocquet, F.A., Elazegui, N.P., Castilla and Teng, P.S. (2000) Rice pest constraints in tropical Asia: quantification of yield losses due to rice pests in a range of production situations. Plant Dis, 84: 357-369.
[5] Savary, S., R.K. Srivastava, H.M. Singh and F.A.Elazegui. (1997) A characterisation of rice pests and quantification of yield losses in the rice–wheat system of India. Crop Protect, 16: 387-398.
[6] D. Abebe, Me. Tadesse, M. Shiferaw. (2020) Hand Hoeing Weeding Frequency on Growth of Tobacco under the Ecological Conditions of Shewa Robit and Bilatte Tobacco Farms, Ethiopia. International Journal of the Science of Food and Agriculture, 4(1) of Food and Agriculture, 4(1), 97-100.
[7] EMA (Ethiopian Mapping Authority) 1988: National Atlas of Ethiopia
[8] Landon, J.R (1991) Booker tropical soil manual: A handbook for soil survey and agricultural land evaluation in the tropics and subtropics. Longman Scientific and Technical, Essex, New York 474p.
[9] Labrada, R., and Parker, C. (1994) Weed Control in the context of Integrated Pest Management. Weed Management for Developing Countries. Edited R. Labrada, J.C. Caseley, C. Parker, Plant Production and Protection Paper No. 120, FAO, Rome, 3-8.
[10] Mishra J.S., and Singh, V.P. (2003) Interference of Euphorbia geniculata in soybean-chickpea cropping system. Indian Journal of Weed Science, 35: 225-227.
[11] Susan, D., and Gayle, B. (1998) Weed identification and control Guide. University of Nevada Cooperative Extension, EB-98-01.
[12] Akobundu, I.O., and Agyakwa, C.W (1987) A handbook of West African weeds. IITA, Ibadan. 312-313.
[13] Thomas, A.G. (1985) Weed survey system used in Saskatchewan for cereal and oil seed crops. Weed Science, 33: 34-43.