Performance of Linseed (Linum usitatissimum L.) Under Different Fertilizer Rates and Weeding Frequencies in South-Eastern Highlands of Ethiopia

Abstract

The effect of fertilizer rates and weeds control on yield and yield components of linseed (Linumusitatissimum L.) were studied in South-Eastern highlands of Ethiopia during the 2009/10 and2010/11 main cropping seasons. Split plot design with three replications was used. The main andsub plots were assigned to four weeding frequencies (W1=no weeding,W2= once weeding at 30 to 35days after sowing, W3=once weeding at 55 to 60 days after sowing, W4=twice weeding at W2 andW3) and eight fertilizer rates (F1=No fertilizer, F2=11.5/11.5 kg/ha N and P 2 O 5 , F3=11.5/23 kg/haN and P 2 O 5 , F4=23/11.5 kg/ha N and P 2 O 5 , F5=23/23 kg/ha N and P 2 O 5 , F6=23/34.5 kg/ha N andP 2 O 5 , F7=34.5/23 kg/ha N and P 2 O 5 , F8=34.5/34.5 kg/ha N and P 2 O 5 ), respectively. DiamoniumPhosphate (DAP) and Urea were used as a source of P 2 O 5 and N, respectively. Linseed variety 'Tolle'was used and sown at a seed rate of 25 kg/ha. Results indicated that tiller numbers, pod numbersand final seed yield of linseed were significantly influenced by the effects of N and P fertilizers andweeds control treatments. The present results showed that W4F5 treatment produced 58% seed yieldadvantage over the control (W1F1) in combined years over locations. Similarly, W4F6 produced seedyield advantage of 57% over the control in combined years over locations. Moreover, the studyrevealed that W4F5 treatment resulted in 9%, 38% and 43% increment in number of tillers/plant,number of pods/plant and seed yield/plant, respectively compared to the control (W1F1).Furthermore, W4F6 treatment resulted in 18%, 48% and 43% increment in number of tillers/plant,number of pods/plant and seed yield/plant, respectively compared to the control. Thus, treatmentsW4F5 to W4F6 were superior in weed control and N and P management practices for linseedproduction in South-Eastern highlands of Ethiopia. Likewise, twice hand weeding alone brought53% seed yield increment compared to the unweeded check. Besides, twice hand weeding resultedin 13%, 45% and 38% increment in number of tillers/plant, number of pods/plant and seedyield/plant, respectively as compared unweeded check. Results have shown that dominant broadleaved and grass weeds vary across locations. The economic analysis indicated that highest netbenefits were obtained from twice hand weeding and application of 23/23 kg/ha N/P 2 O 5 to 23/34.5kg/ha N/P 2 O 5 .