Agronomy

Impacts of Climate Change and Management Practices on Potato (Solanum Tuberosum L.) Production in Tropical Highland Regions of Ethiopia

2024-02-21T10:21:13Z

Impacts of Climate Change and Management Practices on Potato (Solanum Tuberosum L.) Production in Tropical Highland Regions of Ethiopia Ademe, Dereje Various adaptation options are available to the anticipated climate change and variability impacts on potato production systems in the study area. However, impact estimation and adaptation potential evaluation are critical tasks to identify the most viable adaptation options. This study was thus designed to (i) perform climate analysis, (ii) evaluate the performance of SUBSTOR-Potato model, (iii) evaluate impacts of climate change and management practices, and (iv) assess the adaptation role of management practices on potato production in various agroecosystems (AESs) found in the Choke Mountain Watersheds of Northwest Ethiopian highlands. A simulation study conducted for climate change and management practices impacts assessment using a crop simulation model. Two potato varieties (medium maturing and late maturing), three planting dates (March 01, April 01 and June 01) determined based on information from climate analysis and key informants, and four nitrogen rates (0 kg/ha, 40 kg/ha, 80 kg/ha, and 120 kg/ha N) were selected to evaluate their adaptation impacts on potato yield in three climate periods and two scenarios. Input data needed for the study collected from primary and secondary sources. Climate analysis performed at landscape level, whereas the model calibrated and evaluated using field measured data from three AESs. Water limited potential yield, yield gap, and climate change and management practices impact assessment performed using a validated model. Results revealed that all AES warmed significantly in all seasons over the historical analysis period (1981–2016) with higher magnitude of trend in high elevation AES. Rainfall variability was also large across AES, with largest interannual variability found in the dry season. Trends in temperature extremes are generally consistent across sites and AES, but with different implications for agricultural activities in the different AES. Future projections showed significant wetting and increase in precipitation (8–1015 mm additional rainfall) and temperature extremes (More summer days, few chill days, and higher day and night temperature) across AES. High inter-annual variability of rainfall onset (49–84 days) and cessation (41–66 days) dates was observed, and length of the growing period exhibited a significant trend (extended by 6–17 days in some areas and shortened by up to 7 days in other sites) in some AES and greater variability in higher elevation AES (78 – 102 days). Significant increasing trends and variability in dry spells and onset date may severely affect crop production that necessitate the revision of AES specific crop production calendar to minimize crop failure. The results also emphasize the importance of AES-based improved seasonal weather forecasts and tailored climate information services to guide farm decisions. It also concluded that AES level analysis could better provide actionable information for decision makers and growers than site specific and scattered studies. Model evaluation results confirmed that SUBSTOR-Potato model has strong ability to reproduce observed values and is suitable to simulate tuber yield in tropical highlands and similar agroecologies. Results of simulation studies showed that planting season temperature and rainfall had increased in the future climate periods with possible impacts on potato yield. Results further revealed that climate change in the area showed a wider range yield impact (0.25% to 281%) across periods and sites compared to the current practice (6 – 41 t/ha) and major benefit is found in high altitude AESs and in the mid-century period. Future climate change will also resulted in change in water limited potential yield that ranges from –7 t/ha (in AES3) to 40 t/ha (in AES5) in mid-century climate period under RCP8.5. Adaptation option assessment results showed that switching to late maturing variety (-15.4%–180.3%), delayed (June 01) planting time (4.7 – 21.8%) and high nitrogen (120 kg/ha) rate (9.55–28.8%) gave better results. Adaptation role assessment showed that late and mid-planting of late variety with higher nitrogen rates had positive impacts under the current climate and strong adaptation impact in the near-term period. In the mid-century climate period, mid-planting of both varieties with higher nitrogen rates had impact in the current climate with adaptation role in the future climate. Thus, moving the planting time to mid-planting time would have strong adaptation role and minimize GHG emissions, thereby balances trade-off between productivity and mitigation activities.

EFFECTS OF SEEDLING AGE AND TRANSPLANTING DATE ON YIELD AND YIELD COMPONENTS OF TEF [Eragrostis tef (ZUCC.) TROTTER] AT KOBO, NORTH EASTERN ETHIOPIA

2022-02-23T13:09:02Z

EFFECTS OF SEEDLING AGE AND TRANSPLANTING DATE ON YIELD AND YIELD COMPONENTS OF TEF [Eragrostis tef (ZUCC.) TROTTER] AT KOBO, NORTH EASTERN ETHIOPIA Tizazu Mulugeta A field experiment was conducted during the main cropping season of 2014 at Koba, North Eastern Ethiopia, to investigate the effects of seedling age and transplanting date on the yield and yield components ofte.ff A factorial combination of four seedling ages (15, 20, 25 and 30 days old teff seedlings) and three transplanting date, (first transplanting date, second week of July), transplanting delayed by ten days after the first transplanting date and transplanting delayed by 20 days after the first transplanting date) was laid out in a randomized complete block design (RCBD) with three replications using improved teff variety called Zobel (DZ -01- 1821) as a test crop. Phonological traits and yield and yield components were taken as experimental variables . Seedling age resulted in highly significant differences (p < 0. 01) for all Phenological traits and yield and yield components except straw yield which was significant at(P < 0. 05). Transplanting date was also highly significant (P < 0. OJ) affected days to physiological maturity, number of effective tillers plant", number of total tillers plant 1, EFFECTS OF SEEDLING AGE AND TRANSPLANTING DATE ON YIELD AND YIELD COMPONENTS OF TEF [Eragrostis tef (ZUCC.) TROTTER] AT KOBO , NORTH EASTERN ETHIOPIA BY Tizazu Mulugeta Major Advisor: Dr.Getachew Alemayehu ABSTRACT panicle length, grain yield, biomass yield and harvest index. But transplanting date didn't show any significant effect onl 000 grain weight, plant height and straw yield. The interaction effect of transplanting date and seedling age was also highly significant (P < 0. 01) on all Phonological traits and yield and yield components except straw yield. Grain yield of teff had positively and significantly correlation with all yield contributing parameters except days to heading and straw yield. Higher grain yields of 7.29 and 6.91 t ha·' were obtained by transplanting of 25 and 20 days old seedlings on second week of July, respectively. Hence, considering the growth and yield results of the present study, transplanting of 2 5 and 20 days old seedlings on second we~k of July can be suggested v~i~~e~'$..uction

SEEDING RATE AND TIME OF LUPINE (Lupinus a/bus L.} FOOD BARLEY (Hordeum vulgare L.) INTERCROPPING IN GOZAMIN DISTRICT, NORTHWESTERN ETHIOPIA

2022-02-23T12:51:44Z

SEEDING RATE AND TIME OF LUPINE (Lupinus a/bus L.} FOOD BARLEY (Hordeum vulgare L.) INTERCROPPING IN GOZAMIN DISTRICT, NORTHWESTERN ETHIOPIA Sewnet Getahun Food barley and lupine are food crops often traditionally grown in intercropping in north western Ethiopia. But, there is no any documented information about the optimum seeding rate and time of lupine intercropping with barley in Gozamin District northwestern Ethiopia. Hence, a field experiment was conducted on seeding rate and time of intercropping of lupine with barley in Gozamin District to determine the appropriate planting density and time of lupine intercropping for harnessing the possible maximum productivity of barley fields. Factorial combinations offour time of lupine intercropping (on the same date, two weeks, four weeks and six weeks after barley sown) and three planting densities of lupine (5cm, 1 Ocm, l 5cm intra-row spacing between lupine plants) as well as two sole cropping of barley and lupine were laid out in randomized compete block design (RCBD) with three replications. The results indicated that there was no significant difference among all treatment combinations on phenological, vegetative growth and yield related parameters of barley. Except days to 50% emergence and number of grain per pod. However, highly significant differences among treatment combinations were observed for all growth and yield parameters of lupine. In the intercropping system of lupine with barley, the base crop barley completely dominated lupine in all treatment combinations. The land equivalent ratio (LER) was more than one in most cases to show more advantages of intercropping of lupine with barley than their sole cropping separately. The highest LER (1.48) and monitory advantage index (MAI) (17011.8) were recorded in the intercropping of lupine simultaneously with barley at low planting density which was intercropped with l 5cm intra-row spacing between lupine crop. The economic analysis had also confirmed that this treatment combinations (lupine intercropping simultaneously with barley at low planting density) gave the best advantage in the study area that can be recommended for further adoption by barley producing farmers. But, to come up with pragmatic recommendations for wider utilization of intercropping of lupine with barley, similar studies should be carried out further in different areas and cropping seasons.

EFFECT OF SOWING METHOD, SEEDING RATES AND NP FERTILIZERS LEVEL ON GROWTH AND YIELD OF BREAD WHEAT (Triticum aestivum L.} AND WEED INFESTATION IN WESTERN AM HARA REGION OF ETHIOPIA

2022-02-23T08:28:15Z

EFFECT OF SOWING METHOD, SEEDING RATES AND NP FERTILIZERS LEVEL ON GROWTH AND YIELD OF BREAD WHEAT (Triticum aestivum L.} AND WEED INFESTATION IN WESTERN AM HARA REGION OF ETHIOPIA Fekremariam Asargew Two sets of experiments were conducted at Adet and Burie in 2011 main cropping season with the aim of comparing the traditional sowing practice (broadcasting) with drill method of sowing, and of determining the effect of seed and fertilizer rates on the infestation of weeds, and growth and yield of bread wheat. Totally fifteen treatments (combinations of three seeding rates and five NP fertilizer levels) were tested under factorial experiment with Randomized Complete Block Design (RCBD) at three replications. The seeding levels were 125, 175 and 225 kg/ha, and JOO, 150 and 200 kg/ha for broadcast and drill/row methods of planting, respectively. NP fertilizer levels were 92-46, 138-46, 138-92, 184-92 and 230-92 kg/ha N-P205. Plant height, stand count, tiller number, biomass and grain yield, thousand seed weight, hectoliter weight, wet gluten, grain and flour protein and SDS test were among the important data taken. Composite soil samples were also taken before planting and after harvesting from each treatment's plots. Analysis of variance (ANO VA) for all parameters was computed with SAS 12. 0 software and mean separation was done using Duncan's Multiple Range Test (DMRT). As result from Broadcast planting method indicated only the main effects of seeding rate on grain yield and weed biomass; and the main effect of NP rates on stand count, weed biomass, biomass and grain yield were significant (P