Abstract. During the period 2017-2018, the feed quality and productivity of three Sudan grass varieties – Endje 1, Vercors and Super Sweet, one stabilized Sudan grass population – SWT, local sweet sorghum – „Zaharna metla“ population and the sweet sorghum cultivar “Shumensko sladko” were researched in Agricultural Institute – Shumen. Green mass (t/ha), dry matter (%) and dry mass production (%) as well as basic nutritional characteristics by the two swaths of the tested cultivars in brooming phase were controlled. It was found that the sweet sorghum cultivar “Shumensko sladko” gave the highest amount of green mass – 59.5 t/ha by two swaths, and the dry mass yield was the highest from the cultivar Endje 1 – 20.8 t/ha. In terms of chemical composition, the greatest variation was demonstrated in phosphorus content (0.369-0.696%, CV=27.3%), followed by crude fat (1.28-2.39%, CV=26.8%), Ca (0.889-1.572%, CV=21.8%), crude protein (6.05-9.00%, CV=14.6%), nitrogen free extracts (42.05-51.20%, CV=7.6%), crude fiber (32.64-39.26%, CV=6.1%) and mineral substances (8.17-9.61%, CV=5.9%). It can be summarized that all hybrids provide quality hay, however the Bulgarian cultivars Endje 1 and “Shumensko sladko” showed the best nutritional value – compared to Super Sweet, Vercors, SWT and “Zaharna metla”.

The main purpose of cluster analysis is to divide the set of objects under study characterized by a set of features into groups(clusters) that are homogeneous in the appropriate sense. A positive feature of cluster analysis is the ability to compress a largeamount of information, systematize it, build a scientifically based classification, identify the internal relationship between theunits of the population under study. The aim of the article is to identify promising samples of sorghum × drummondii accordingto the main economic characteristics based on cluster analysis for further use in breeding for heterosis in the conditions of SaratovOblast. Grouping of samples allows for examining the composition of each cluster as fairly identical source material in terms ofthe severity of the indicators. During the period from 2015 to 2017, 32 samples of sorghum × drummondii were evaluatedaccording to 12 economically valuable characteristics, which were subjected to statistical processing. At the 22nd iteration stepwith a Euclidean distance of 14.4, the samples were grouped into 10 clusters. Cluster differences were observed to be significant,except for the "1,000 Seed Weight" feature. The study distinguished clusters 1 and 5 based on the intensity of the initial growth.The second cluster is characterized by the number of differences in the parameters of the largest leaf, the width of the flag leaf,and grain yield. Clusters 3 and 4 did not differ significantly in most features. In the 6th cluster, differences were noted accordingto the following indicators: "the extension of the panicle leg", "height at maturity", "inflorescence length" and "length of the flagleaf". The 7th cluster revealed differences in the width of the flag leaf, the width of the inflorescence, and grain yield. The 8thcluster distinguished itself by the parameters of the flag leaf and the yield of green biomass. In the 9th cluster, differences wererevealed on the basis of: "height at maturity" and the parameters of "inflorescence", "largest leaf". The last cluster wasdistinguished by the greatest number of differences in the parameters of the largest leaf (in length 8 and 6 in width), grain yieldand green biomass, the extension of the panicle leg. The results obtained are used in the selection of components of crosses inthe selection of grass sorghum hybrids.

The anthropogenic introduction of plants has a long history dating to the beginning of civilization. Initially of a small,local nature, this activity gradually moved to a global scale. While solving the issues of food security, modern society showslittle awareness of the new environmental problems created by it in the form of uncontrolled artificial settlement of new typesof flora on the continents. Their ability to penetrate the environment can lead to the displacement of native forms of the plantworld.

A continuous long-term field experiment (2008-2018) was conducted in Xinjiang, north-western China, to assess the impact of farmyard manure (FYM) and inorganic fertilisers on the sustainable biomass yield of sweet sorghum cultivar (Xingaoliang No. 3) and soil chemical properties. Seven treatments, associated with nitrogen (N), phosphorus (P), potassium (K), FYM, and their different combination, were compared with the control plot (CK). As a result, the treatments NP, PK, NK, NPK and NPKM significantly increased the average biomass yields by 30-48% over CK. The 12 t/ha FYM per year with NPK (NPKM) increased both the yield and total soluble solids (TSS) by 48% and 7.9%, respectively, while the 18 t/ha/year application rate of FYM had an adverse effect on yield. Stem TSS, soil available N and K for all treatments decreased while soil organic carbon, soil total salt and the available P for FYM applied treatments increased over the years. The soil pH stabilised at 7.8-8.2 at the end. In conclusion, the 12 t/ha/year of FYM is the most efficient rate for a single application or incorporation with inorganic fertilisers. A more reasonable application rate of N and K fertiliser to increase the yield and irrigation rate to reduce soil salt needs for further investigation.

One of the most promising and difficult challenges for field phenotyping is accurate and reliable counting of sorghum panicles using drone imagery both from RGB and multispectral cameras. In this paper, we present a hybrid Machine Learning method for sorghum panicle identification and counting. The methodology first consists in building a Machine Learning classifier following the two most used methods in the literature for drone and agriculture applications: Support Vector Machine Learning (SVM) and, Artificial Neural Networks (ANN). The present dataset includes 5300 images, and 60% of the dataset were used for training and 20% for testing and validation. Following the results obtained from these models, image segmentation using super-pixel affinity propagation and k-means clustering was used based on simple linear iterative clustering. With an accuracy of 99%, SVM gave a superior performance also in terms of precision and kappa when compared to the ANN model whose accuracy was 98%. Concerning the SVM, a radial basis kernel was used, and the sigma parameter was kept constant at a value of 5.6 determined analytically.

This study investigated why biscuits made from sorghum flour have a similar texture to wheat biscuits despite the absence of gluten in sorghum dough. Electron microscopy revealed that the sorghum prolamin protein bodies remained intact in the sorghum biscuits and hence were unlikely to contribute to biscuit structure and texture. Polarized light microscopy showed that the starch granules in the sorghum biscuits were not gelatinized. Increasing dough water content increased the breaking strength and brittleness of sorghum biscuits. However, increasing the proportion of pre-gelatinized sorghum flour in the dough reduced the breaking strength of the sorghum biscuits, indicating that starch gelatinization weakened the biscuit structure. In contrast, increasing the sucrose content of the dough increased sorghum biscuit breaking strength and brittleness. At 20% sucrose (flour basis), the sorghum biscuits had similar breaking strength and brittleness to both Marie and sugar-snap wheat biscuits. DSC and X-ray diffractometry showed that the sugar in both the sorghum and wheat biscuits was in the glassy state and polarized light microscopy revealed that the sugar glass embedded or enveloped the sorghum biscuit flour particles. It is concluded that this sugar glass matrix is responsible for the strength and cohesiveness of the sorghum biscuits.

Background. In mixed crop livestock farming systems in Ethiopia, sorghum stover and other crop residues are a strategic livestock feed resource.  Farmer’s decisions and intensity of use of sorghum stover for feed than other uses are closely associated with biophysical and socioeconomic characteristics. Objective. This study explores determinants of sorghum biomass uses for livestock feed in three major sorghum growing agroecological zones of Ethiopia. Methodology. Tobit and double hurdle models were run and likelihood ratio test was performed to select most suitable estimation technique. Result. Allocation of sorghum stover for feed showed a significant association with sorghum growing agro-ecological zones, highest in the lowland (86.73%) and the lowest in highland sorghum growing agroecological area (61.75%). Econometric model result revealed that among other factors; availability of feed from grazing and other crop residues had a negative effect on decision to use and intensity of use of sorghum stover for feed. Household’s livestock ownership and family size had positive effects.  Implication. Decision variables influenced household’s decision and intensity on use of sorghum stover for feed at three major sorghum growing zone differently. Conclusion. Knowledge generated through this study may help any research and development efforts to enhance productivity of sorghum biomass for livestock feed and livestock improvement strategies. Keywords:  Agroecology; Crop residue; Econometric models; Feed resources; Sorghum stover. Keywords:  Agroecology; Crop residue; Econometric models; Feed resources; Sorghum stover.

Sorghum [Sorghum bicolor (L.) Moench] is the main food staple grain widely cultivated in sub-Sharan Africa including Uganda. There is a lack of current information on sorghum production constraints and varietal trait preferences in the major sorghum production areas in Uganda. Therefore, the objective of this study was to assess the sorghum production constraints and farmer preferences for sorghum variety in Uganda. A participatory rural appraisal study was undertaken in four selected sorghum production districts in Uganda (Kumi, Bukedea, Oyam and Gulu). Data were collected through surveys using semi-structured questionnaires and focus group discussion involving 128 and 55 participants, respectively. Data were subjected to parametric and non-parametric statistical analyses to draw inferences. A lack of improved sorghum varieties was the major sorghum production constraint reported by 82.8% of participants. Farmer preferred ideal sorghum varieties were short to medium plant height with high grain yield. The quality attributes mostly preferred by farmers were baking quality, nutrition, and seed colour. Farmers in the study areas mainly grew unimproved sorghum varieties with low food values. Overall, the study provides the current evidence on sorghum production constraints and farmer-preferred attributes that will guide sorghum nutritional quality breeding with farmer preferred traits.

Sorghum [Sorghum bicolor (L.) Moench] is the main food staple grain widely cultivated in sub-Sharan Africa including Uganda. There is a lack of current information on sorghum production constraints and varietal trait preferences in the major sorghum production areas in Uganda. Therefore, the objective of this study was to assess the sorghum production constraints and farmer preferences for sorghum variety in Uganda. A participatory rural appraisal study was undertaken in four selected sorghum production districts in Uganda (Kumi, Bukedea, Oyam and Gulu). Data were collected through surveys using semi-structured questionnaires and focus group discussion involving 128 and 55 participants, respectively. Data were subjected to parametric and non-parametric statistical analyses to draw inferences. A lack of improved sorghum varieties was the major sorghum production constraint reported by 82.8% of participants. Farmer preferred ideal sorghum varieties were short to medium plant height with high grain yield. The quality attributes mostly preferred by farmers were baking quality, nutrition, and seed colour. Farmers in the study areas mainly grew unimproved sorghum varieties with low food values. Overall, the study provides the current evidence on sorghum production constraints and farmer-preferred attributes that will guide sorghum nutritional quality breeding with farmer preferred traits.

MAIN CONCLUSION : An overview is presented of recent advances in our knowledge of responses and mechanisms rendering adaptation to saline conditions in sorghum. Different strategies deployed to enhance salinity stress tolerance in sorghum are also pointed out. Salinity stress is a growing problem worldwide. Sorghum is the fifth key crop among cereals. Understanding responses and tolerance strategies in sorghum would be therefore helpful effort for providing biomarkers for designing greatest salinity-tolerant sorghum genotypes. When sorghum exposed to salinity, salinity-tolerant genotypes most probably reprogram their gene expression to activate adaptive biochemical and physiological responses for survival. The review thus discusses the possible physiological and biochemical responses that confer salinity tolerance to sorghum under saline conditions. Although it is not characterized in sorghum, salinity perceiving and transmitting signals to downstream responses via signaling transduction pathways most likely are essential strategy for sorghum adaptation to salinity stress. Sorghum has also shown to withstand moderate saline environments and retain the germination, growth, and photosynthetic activities. Salinity-tolerant sorghum genotypes show the ability to exclude excessive Na⁺ from reaching shoots and induce ion homeostasis. Osmotic homeostasis and ROS detoxification are also evident as salinity tolerance strategies in sorghum. These above mechanisms lead to re-establishment of cellular ionic, osmotic, and redox homeostasis as well as photosynthesis efficiency. It is noteworthy that these mechanisms act individually or co-operatively to minimize the salinity hazards and enhance acclimation in sorghum. We conclude, however, that although these responses contribute to sorghum tolerance to salinity stress, they seem to be not adequate at higher concentrations of salinity, which agrees with sorghum ranking as moderately salinity-tolerant crop. Also, some of these tolerance strategies reported in other crops are not well studied and documented in sorghum, but most probably have roles in sorghum. Further improvement in sorghum salinity tolerance using different approaches is definitely necessary to meet the requirements of its harsh production environments, and therefore, these approaches are addressed.