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Stem rust caused by Puccinia graminis f. sp. tritici (Pgt) is one of the most important diseases of wheat worldwide. Breeding for resistance to diseases is the most important approach for mitigation of yield losses. This study was conducted to estimate the diversity of all stage stem rust resistance (ASR) genes on the 142 durum wheat landrace accessions at seedling stage. The study was conducted in greenhouse at Ambo Plant Protection Research Center on the 142 durum wheat landrace accessions using 20 differential lines, one susceptible line (McNair), and eight Pgt races. The result depicted the presence of Sr7b, Sr8a, Sr9b, Sr10, Sr11, Sr13, Sr17, Sr30, Sr31, Sr36, and SrTmp in the Ethiopian durum wheat accessions. Among the 142 durum wheat accessions, 83 accessions were identified for possessing single ASR genes, and four accessions including the universal susceptible line (McNair) did not have effective resistance genes to the pathogen races tested in this study. The remaining 55 accessions had either a combination of two resistance genes, unknown number and kind of genes, or unidentified genes displaying resistance across all the pathogen races. This study demonstrated the prevalence of significant genetic diversity for stem rust ASR genes in the Ethiopian durum wheat landraces.

Ethiopia is not self-sufficient to meet its increasing wheat demand from domestic production partly due to a lack of improved seeds. Efforts are undertaken to fill the gap through off-season production of wheat using supplemental irrigation and modern cultivars adapted to arid areas. This study was carried out to evaluate the genetic variability and adaptability of 15 Ethiopian bread wheat genotypes at different agroecologies in Wolaita and Dawuro zones, Ethiopia. The field experiment was conducted at three locations using a randomized complete block design with three replications during the 2019/2020 main cropping season. Analysis of variance based on 11 morphological agronomic traits and two major wheat diseases revealed that there were highly significant differences ( P < 0.01 ) among the genotypes for all the traits studied at each location and combined over locations. The top three cultivars viz. Alidoro, Galema, and Honqolo exhibited higher average grain yield (GY) of 4.54 t/ha, 4.36 t/ha, and 4.0 t/ha, respectively, combined over locations. Eight of the traits (72.73%) exhibited moderate (30–60%) to high broad-sense heritability ( h b 2 > 60%) values. High h b 2 associated with high genetic advance as percent of mean was observed for the severity of both stem and yellow rust diseases combined over locations. GY was significantly related to aboveground biomass at all locations. This study depicted that cultivar Alidoro had wider adaptability for grain yield and resistance to wheat rusts.

The use of improved varieties with wider adaptability and stability is necessary to maximize the productivity of durum wheat. However, due to genotype by environment interaction (GEI) effect, superior genotypes in one environment could be inferior in other environments. Hence, a multi-environmental trial (MET) was commenced to determine the magnitude of GEI effect and identify stable durum wheat genotypes across environments. The MET was conducted using nine durum wheat cultivars in randomized completely block design with three replications across four contrasting locations in 2020 crop seasons. The result of combined analysis of variance showed the presence of significant differences among the main effects; environments, genotypes, and GEI effects for grain yield. The additive main effects and multiplicative interaction (AMMI) combined ANOVA for main effects of environment, genotype, and GEI revealed highly significant differences among cultivars with 66.2%, 26.4%, and 7.3% share of sum square variation, respectively, of the total variation. AMMI and genotype plus genotype by environment (GGE) Bi-plot analysis identified the cultivars Fetan, Denbi, and Mangudo as high yielders and adaptive to the favourable locations. AMMI stability value and yield stability index identified Mangudo as the most stable and adaptive cultivar across locations. The AMMI Bi-plot analysis showed that the first two interaction principal component analysis (IPCAs) captured 90.45% of the total interaction sum of squares (ISS), where IPCA1 took 55.61% and IPCA2 accounted for 34.84% of GEI effects. This study identified Mangudo as the most stable cultivar with acceptable yield while Fetan was the top yielder genotype across locations.

A field experiment was conducted at Damot Gale District, Wolaita Zone, SNNPRS to evaluate the response of barely varieties to nitrogen and phosphorus fertilizer application since the response varies from location to location due to several factors. Thus, there is a need to determine specific nitrogen and phosphorus fertilizer requirement of specific variety. The barley varieties (HB1370 and Shage) were used as test crop and the experiment contained factorial combination of four levels of N/P (0/0, 23/10, 46/20, 69/30 kg ha-1) and was laid out in randomized complete block design with three replications. The results from this study indicated that nitrogen and phosphorus fertilizer showed no significant effect on number of days to heading while number of fertile tillers, total biomass and yield were significantly increased by application of nitrogen and phosphorus. However, the effects of nitrogen and phosphorus were significant (P < 0.05) on plant height, spike length, number of seeds per spike and grain yield. In general, grain yield tended to be higher under NP 69/30 kg ha-1 treatment (2.02t/ha). In contrast, the lowest grain yield (0.86t/ha) was obtained from 0/0 NP treatment, although the interaction effects of nitrogen and phosphorus were significant on treatments with varieties and balanced amount of nitrogen and phosphorus. The future studies should articulate towards the studies involving more varieties, multi-location and additional rates of nitrogen and phosphorus applications, under diverse management practices such as research and farmer’s field’s conditions, which may facilitate fine-tuning of fertilizer recommendations.

A field experiment involving seven improved sorghum [Sorghum bicolor (L.) Moench] varieties and one local check was carried out at Kako farmers’ training center during the 2006 main cropping season to identify the best performing variety to the lowlands of South Omo Zone. The sorghum varieties included in the field experiment were seven improved (Seredo, Meko-1, 76TI#23, Gambella 1107, Teshale, Gubiye, Abshir) and a local check. The experimental design was a randomized complete block design (RCBD) with three replications. Phenological and growth parameters such as yield and yield components, total biomass and harvest index were studied. The result showed that all phenological and growth parameters were significantly affected by variety except number of tillers and panicle length per plant. There was a proportional increment on the number of tillers per plant observed for the improved sorghum varieties over the local check. Grain yield, total biomass, 1000 seeds weight and harvest index were significantly affected by variety. Grain yield advantages of 74.26%, 64.96% and 58.06%, were obtained from the improved sorghum varieties Teshale, Meko-1 and Gambella 1107, respectively over the local check. The highest grain yields of (3.3667 t ha-1) and (2.4733 t ha-1) were recorded for the varieties Teshale and Meko-1, respectively. Therefore, it can be concluded that use of the improved sorghum varieties such as Teshale or Meko-1 is advisable and could be appropriate for sorghum production in the test area even though further testing is required to put the recommendation on a strong basis.

A field experiment involving eleven improved banana (Musa paradisiacal var. sapiertum) varieties and one local check was carried out at Jinka Agricultural Research Center during the 2006 to 2009 cropping seasons under rain fed conditions to identify the best performing variety to the target areas of South Omo Zone. The banana varieties included in the field experiment were eleven improved (Kampala, Pisang, Lacatan, Poyo, Dwarf Cavendish, Giant Cavendish, Butuzua, Grand Naine, Robusta, Williams-1, Williams-2) and a local check. The experimental design was a randomized complete block design (RCBD) with three replications. Phenological and growth parameters, bunch yield and yield components were studied. The result showed that days to flowering were significantly affected by variety while days to maturity were not significantly influenced by variety. Psedostem height was significantly affected by variety; whereas, variety had brought no significant effect on psedostem circumference. All the yield and yield components studied were significantly affected by variety except finger diameter. Bunch yield advantages of 59.11%, 55.87% and 47.55%, were obtained from the improved banana varieties Dwarf Cavandish, Giant Cavandish and Poyo, respectively over the local check. The highest bunch yields of (45.333 t ha-1) and (42.000 t ha-1) were recorded for the varieties Dwarf Cavendish and Giant Cavendish, respectively. Therefore, it can be concluded that use of the improved banana varieties such as Dwarf Cavendish or Giant Cavendish is advisable and could be appropriate for banana production in the test area even though further testing is required to put the recommendation on a strong basis.