Improved agronomic practices increases yield potential of chickpea in different agroecology of the country. In this view a field experiment was conducted to assess the influence of inter-and intra row spacing on yield and yield components of chickpea (Cicer arietinum L.) in Jimma Horro district of Kellem Wollega Zone, Western Oromia, Ethiopia. The treatment consisted of three inter-row spacing (20, 30 and 40 cm) and four intra-row spacing (5, 10, 15 and 20 cm). The experiment was laid out in a randomized complete block design in factorial arrangement with three replications. The highest (52) number of pods plant-1 was obtained with the interaction effect of 40 cm inter and 20 cm intra row spacing. The highest dry biomass (8457 kg ha-1) was recorded at 20 cm × 5 cm spacing while the lowest dry biomass (5413 kg ha-1) was recorded at 40 cm × 20 cm spacing combination. Significantly  higher  (248 g) 1000 grain weight was recorded under 40 cm with 20 cm spacing and lowest (165 g) 1000 grain weight under 30 cm x 5 cm row spacing. The highest (1625 kg ha-1) seed yield of chickpea was obtained from 30 cm x 15 cm and the lowest seed yield (1096 kg ha-1) was recorded from 20 cm x 5 cm row spacing. The highest harvest index (34.03%) was achieved for the interaction of 40 cm inter- and 20cm intra-row spacing and the lowest harvest index (12.14%) under 20 cm x 5 cm row spacing. Thus 30 cm inter-row with 15 cm intra-row spacing can tentatively be recommended for the production of chickpea in the study area as compared to the current recommendation of 30 x 10 cm. Further research would be needed at more locations and seasons to give conclusive recommendations.

Background: Phosphorus is one of the limiting plant nutrients in most soil due to its fixation with metal ions both in acidic and alkaline soil. However, some soil bacteria have potential to solubilize the cation-fixed phosphorus and make it available to plants.Methods: Sixty-six cowpea root nodule bacterial species were tested for inorganic phosphate solubilization (PS). PS potential of the isolates from Ca3 (PO4)2, AlPO4 and FePO4 were tested on four different kinds of agar media. Solublization efficiency was determined as Solubilization Index (SI) on agar media and quantity of bioavailable phosphorous on broth media. Result: About 30% of the bacterial isolates, out of which 60% endophytes were Ca3 (PO4)2 solubilizers on Pikovskaya medium but did not grow on media containing AlPO4 and FePO4 as sole P sources. Isolates showed significant variation (p less than 0.05) in Ca3 (PO4)2 solubilization efficiency on the different culture media and ECE-21 (Pseudomonas putida) was versatile in solubilizing Ca3(PO4)2 from the four test media. However, ECE-26A (Bacillus subtilis) showed the highest PS in broth media (140.8 µg ml-1) indicating the moderate correlation (r=0.5578; p less than 0.05) of PS between solid and liquid media. Amounts of P solubilized and pH change of the culture filtrate was inversely correlated (r=-0.731; p less than 0.01). In general, ECE-21 was the most efficient P solubilizer (SI=2.67±0.1; P=87.74±7.4µg ml-1) solublizers and hence can be an ideal candidate as inoculants for the crop production in Ethiopia after field evaluation.

The knowledge of nature and the magnitude of divergence existing in the breeding materials are useful to identify suitable parents or populations to combine favorable genes. Thus, 28 barley genotypes were evaluated at Gitilo site in RCB design with three replications during the 2018/19 season. The aim of the study was to investigate the magnitude of genetic divergence among the existing breeding materials. The result revealed that the barley genotypes were grouped into four clusters. The inter-cluster distance was greater between clusters I and II, followed by cluster II and III and then between clusters II and IV, I and IV, III and IV, between I and III so that crossing among parents from distant clusters result in wide array populations with desirable alleles. Besides this, cluster mean analysis showed clusters IV and III contained desirable characters for high yield potential including net blotch and scald resistance indicating their suitability for direct variety development. The variation studied through principal component analysis revealed four principal components (PC1:32.7%, PC2:22.4%, PC3:16.7% and PC4:11.6%) accounting for about 83.4% of the total variation. Furthermore, the biplot graph identified barley genotypes or populations 21, 20, 24 and 12 as desirable parents mainly for grain yield, biomass yield per plant and thousand kernel weights.

Mixed application of organic and inorganic fertilizers in mixture improves soil fertility and crop productivity. However, the identification of combined application level is important. Therefore, a field experiment was conducted in 2020 in the Guto Gida district to assess the effect of maize cob biochar levels and inorganic NPS fertilizer rates on the growth and yield of maize. The study was conducted in factorial combinations of five rates of maize cob biochar and three rates of inorganic NPS fertilizer using a randomized complete block design with three replications. The main effect of the biochar level and NPS rate significantly affected crop phenology and biomass yield, whereas the number of kernels ear−1 was affected by the main effect of NPS rate. The combined application of biochar and NPS fertilizer significantly influenced plant height, leaf area index, ear weight, thousand kernel weight, grain yield, and percentage of grain yield. The interaction of biochar at 8 t·ha−1 with 100 kg·ha−1 NPS resulted in highest leaf area index (5.56), grain yield (7.03 t·ha−1), and yield increment (18.11%) followed by 8 t·ha−1  × 50 kg·ha−1 and all biochar levels with 100 kg·ha−1 NPS. In addition, the highest values of ear weight (276 g) and thousand kernel weight (47.81 g) were recorded in plots treated with combined application of biochar and NPS fertilizer at rates of 8 t·ha−1 × 50 kg·ha−1 and 4 t·ha−1 × 100 kg·ha−1, respectively, whereas plots not treated with both biochar and NPS resulted in lowest yield followed by 0 t·ha−1 × 50 kg·ha−1. In conclusion, integrated application of maize cob biochar at 8 t·ha−1 with NPS fertilizer at 50 kg·ha−1 improved the yield of maize by about 16.85% with net benefit of 61700.50 ETB ha−1 and marginal rate of return 733.68%, and therefore, the application of biochar at this rate with mineral NPS fertilizer at 50 kg·ha−1 is considered as suitable for the study area.

Combining ability analysis provides information about the gene action involved in the expression of a trait and facilitates breeding of superior cultivars. Hence, 45 hybrids evolved from 10 parent half-diallel were evaluated for combining ability to identify good general combiners and superior cross combinations for high ethanol yield from sweet sorghum. RSSV-21-2 has been identified as the best general combiner. It can be used in pedigree breeding programme for the incorporation of desired traits for enhancing ethanol yield. ARS-SS-35-1 × NSS-218 and ARS-SS-83 × NSS-221-2 have been identified as the best specific combinations. These could be exploited in heterosis breeding programme.