7 pp. / Forage sorghum is commonly grown in Arizona for silage for dairy cattle and is valued for its lower nitrogen fertilizer and water requirements compared to corn. Five forage sorghum hybrids were evaluated in a study conducted at the Maricopa Agricultural Center in 2015. The hybrids tested did not differ in yield or overall feeding quality (TDN, total digestible nutrients) although some differences in heading, plant height, moisture content, and some specific quality parameters were detected.

9 pp. / Sorghum has the advantage compared to corn in that it uses less water and fertilizer, but feeding quality of sorghum is usually less than corn. The purpose of this research is to compare the yield and quality of sorghum grown with differing frequency of irrigation water application. Forage sorghum was grown at the University of Arizona Maricopa Agricultural Center with irrigation intervals of 1, 2, and 3-weeks corresponding to 76, 44, and 37 inches of applied water. Forage yield at 72% moisture was 20.6, 18.8, and 16.5 tons/acre for the 1-, 2-, and 3-week irrigation intervals, respectively. Forage quality in terms of milk per ton of forage was not affected by irrigation interval, but some differences were measured in certain components of feed quality. Forage yield profit was maximized at the 2-week irrigation interval due since the increased water cost of the 1-week interval was not compensated by the yield increase at this irrigation frequency.

13 pp. / A nitrogen fertilizer study was conducted in order to determine the effect of N rates on forage sorghum yield and quality and to develop tissue testing guidelines for fertilizer application to forage sorghum. The study was conducted at the University of Arizona Maricopa Agricultural center on sandy clay loam soil irrigated using the flood method. Forage sorghum was fertilized with six N rates varying from 0 to 250 lb N/acre in 50 lb N/acre increments. The whole plant, lower stem, and most recently expanded leaf were sampled five times during the growing season and analyzed for N content in order to establish tissue N guidelines for fertilizer application. The plant part that was most sensitive to N fertilizer application and plant N status was lower stem. Leaf and plant N levels were not affected by fertilizer application. The stem nitrate and stem N tests were able to identify N deficient plants very early in the season, long before plant growth was affected by the N deficiency, unlike leaf and plant N. Forage yield at final harvest fitted to a quadratic function was maximized at the 250 lb N/acre N rate. However, the yield increase with any amount of fertilizer did not pay for the cost of the fertilizer and the most economical N rate for yield was no N fertilizer applied at all. In terms of milk per acre, the maximum was achieved at 150 lb N/acre, and the economic optimum in terms of milk was slightly less than this amount of fertilizer.

There is a conflict of interest between the sorghum producers, for whom condensed tannins in sorghum have agronomic advantages, and sorghum users for whom condensed tannins in sorghum are perceived as nutritionally harmful and unpalatable. However, in recent years there has been growing interest in food phenolics due to their antioxidant potential. Thus, enhancing the content of phenolic compounds in plant foods through selective breeding and/or genetic improvement is now being viewed as a potent dietary option for disease prevention and control. However, the objectionable sensory attributes (bitterness and astringency) of phenolic compounds, especially condensed tannins, have resulted in low consumption of foods rich in these compounds. This study investigated the sensory attributes of products of sorghums varying in total phenol and condensed tannin content as well as their acceptance. A descriptive sensory panel described the sensory attributes including bitterness and astringency of two products, sorghum rice and bran infusions of six sorghum cultivars: three containing tannins and three with no detectable tannins. The products of all the sorghums (tannin and tannin-free) were perceived to different degrees as both bitter and astringent. The products of sorghums with the highest total phenol and tannin content were most bitter and astringent while those from tannin-free sorghums with the lowest total phenol content were least bitter and astringent. The products of NS 5511 (tannins - 1.8% catechin equivalents CE), were perceived similar in both bitterness and astringency to those of a tannin-free sorghum (PAN 8564). Using the Dual Attribute Time Intensity (DATI) sensory method the descriptive sensory panel determined the intensity and time course of bitterness and astringency of bran infusions of sorghums varying in total phenol and condensed tannin content. The infusion from the sorghum with the highest condensed tannin content (PAN 3860) was perceived as most bitter and most astringent and that from the tannin-free sorghum with the least total phenol content (Phofu) was least bitter and astringent. Bitterness of the sorghum infusions developed and reached maximum intensity significantly faster than astringency. The total duration of the astringency sensation lasted significantly longer than bitterness. The more bitter and more astringent the sorghum was, the longer the persistence of the bitter and astringent after-taste. The infusion of NS 5511 was again perceived similar to tannin-free sorghums in both bitterness and astringency. These findings seem to suggest that there is a condensed tannin threshold level at which the tannins are not ‘strongly’ perceived and thus are not objectionable. A consumer panel classified by 6-n-propylthiouracil (PROP) taster status assessed the colour, texture, flavour and overall liking of sorghum rice of two tannin-containing (tannin) sorghums and two tannin-free sorghums. The sorghum rice from PAN 3860, with the highest tannin content, received significantly lower acceptance ratings for all the sensory attributes than the other sorghums. With the exception of appearance, the acceptance of the sorghum rice from the tannin sorghum NS 5511 was not significantly different from that of the two tannin-free sorghums. The PROP tasters (medium and super) could distinguish differences among the sorghum cultivars varying in tannin content levels which presumably led to the significant difference in their acceptance ratings for the most bitter and astringent sorghum compared to others. On the other hand the non tasters preferred the cultivars equally, presumably because they could not detect taste differences (in bitterness and astringency) between the sorghum cultivars. The results of the consumer panel confirm the predictions made from the descriptive sensory panel results that not all the tannin sorghum products would be objectionable to consumers. It is proposed that the condensed tannin threshold level is 2.0% CE inclusive of the tannin content level of NS 5511 (1.8% CE). It is recommended that future breeding programmes investigate production of sorghums like NS 5511 with condensed tannin levels that fall within this threshold limit. The level of condensed tannins in these sorghums would provide the agronomic advantages for the farmer by reducing pre-harvest and post-harvest losses as well as provide the antioxidant benefits associated with them without negatively affecting the nutritional value of the food/feed. Since the negative sensory properties of these sorghums are not strongly perceived they would not be objectionable to consumers, thus making them a promising health option for millions of people. / Thesis (PhD)--University of Pretoria, 2009. / Food Science / unrestricted

A field study was conducted at ARC - Grain Crops Institute, Potchefstroom Experimental Farm and at Taung Crop Production Center during 2006/07 summer growing season. Twenty sorghum genotypes were planted in two separate blocks, under full irrigation and rain fed conditions with plot size of 4 rows x 5 m x 0.9 m giving a density of 55 555 plants ha-1. The experiment was laid out in a randomised complete block design replicated three times. The irrigated block received scheduled irrigation from planting until maturity, while the rain fed block received irrigation prior to germination only. Agronomic traits measured were plant height, stem diameter, biomass, flowering date, panicle exertion, panicle length, leaf area, grain yield, and thousand seed mass at Potchefstroom and Taung experiments. Drought susceptibility index (DSI) was quantified using the formula: DSI = [1 - (Ydi/ Ypi)]/ [1 - (YD/YP)] and %yield reduction (%YR) was calculated using the formula: %YR = (Ypi –Ydi)/ Ypi x 100. Significant variations among genotypes with regard to grain yield (GYLD), plant height (PH), panicle length (PL), biomass (BM), stem diameter (SD), panicle exertion (PEx), and 1000 seed mass (TSM) were observed at Potchefstroom under rain fed conditions, while under irrigated conditions significant variations were only observed for GYLD, PH, PL, BM, days to 50% flowering (DF), SD, leaf area (LA), PEx and TSM. At Potchefstroom genotypes varied significantly with regard to PH, PL, BM, DF, SD, LA, PEx and TSM under rain fed conditions, while under irrigated conditions genotypes varied with all traits measured with exception of harvest index (HI) and relative water content (RWC). At Potchefstroom, soil water deficits significantly affected GYLD, PH, HI, PEx and RWC, while at Potchefstroom soil water deficits significantly affected GYLD, PH, SD, LA, PEx, TSM and RWC. Genotypes varied with their level of resistance/ susceptibility to soil water deficits at both Potchefstroom and Taung. Some remarkable correlations among traits measured were observed under rain fed and irrigated conditions and across the treatments at both Potchefstroom and Taung. At Potchefstroom, significant correlation was only observed between drought susceptibility index (DSI) and PH under rain fed conditions, while at Potchefstroom negative and significant correlation was only observed between DSI and GYLD under rain fed conditions. At Potchefstroom, GYLD under rain fed significantly related to GYLD under irrigated conditions and across the treatments. However, GYLD under irrigated conditions significantly related to GYLD across the treatments. At Potchefstroom, GYLD under rain fed conditions significantly correlated with GYLD across soil water regimes, while GYLD under irrigated conditions significantly correlated with GYLD across the treatments. Genotypes that exhibited the combination of high yield potential and resistant traits were recommended. Genotypes that exhibited high resistant traits with low yield potential were recommended for breeders to incorporate those traits into susceptible genotypes with high yield potential. / Dissertation (MInstAgrar)--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted

Please read the abstract in the section 00front of this document / Thesis (PhD (Food Science))--University of Pretoria, 2006. / Food Science / unrestricted

Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-09-25T21:35:07Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Rejane Maria Ferreira da Silva.pdf: 2199357 bytes, checksum: e319199462586680a356da672d1d0799 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-09-28T18:18:53Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Rejane Maria Ferreira da Silva.pdf: 2199357 bytes, checksum: e319199462586680a356da672d1d0799 (MD5) / Made available in DSpace on 2018-09-28T18:18:53Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Rejane Maria Ferreira da Silva.pdf: 2199357 bytes, checksum: e319199462586680a356da672d1d0799 (MD5) Previous issue date: 2016-02-24 / CNPq / Os fungos endofíticos são caracterizados por habitarem o interior (intra ou intercelularmente) dos tecidos vegetais, não causando aparentemente nenhum dano a seus hospedeiros. O sorgo (Sorghum bicolor (L.) Moench) é uma gramínea de origem africana, pertencente à família Poaceae. Encontra-se em quinto lugar entre os cereais mais plantados no mundo. Devido a importância dos fungos endofíticos em culturas agronômicas, este trabalho teve por objetivo determinar a diversidade de fungos endofíticos em folhas sadias de S. bicolor nos períodos de pré e pós-floração, em cultivos de Goiana e Serra Talhada, Pernambuco. No laboratório, as folhas foram lavadas com água corrente e sabão neutro, e com auxílio de um furador esterilizado foram feitos discos foliares (6 mm), posteriormente desinfestados em álcool 70% por 30 segundos, em hipoclorito de sódio (NaClO) a 2% por 3 minutos e realizadas duas lavagens com água destilada esterilizada. Os fragmentos foram transferidos para placa de Petri, em triplicata, contendo ágar malte acrescido de cloranfenicol (50 mg L⁻¹), para posterior identificação taxonômica utilizando literatura especializada para análise morfológica dos táxons. Para confirmação dos táxons, o DNA foi extraído, sendo amplificada e sequenciada a região ITS ("internal transcribed spacer") do rDNA. Foram analizados 1728 fragmentos de folhas. Foram isolados 476 espécimes de fungos endofíticos, distribuídos em 40 morfotipos/filotipos. Cochliobolus hawaiiensis, Colletotrichum falcatum e Epicoccum sorghi foram as espécies mais frequentes. Os táxons identificados são pertencentes ao filo Ascomycota (classes Eurotiomycetes, Dothidiomycetes, Sordariomycetes) e subfilo Mucoromycotina (ordem Mucorales). Acremonium borodinense, Arthrinium sp., Cochliobolus hawaiiensis, Engyodontium album, Epicoccum sorghi, Hypoxylon griseobrunneum, Phyllosticta capitalensis, Mucor irregularis, Mucor indicus, Mucor sp., Paraphaeosphaeria sp., Periconia macrospinosa, Purpureocillium lilacinum e Talaromyces apiculatus são citadas pela primeira vez como endofíticos de sorgo. / The endophytic fungi are characterized by inhabiting the interior (intra or intercelularly) of plant tissues, apparently not causing any damage to their hosts. Sorghum (Sorghum bicolor (L.) Moench) is a grass of African origin belonging to the Poaceae family. It lies in fifth place among the most planted grain in the world. Due to the importance of endophytic fungi in agronomic crops, this study aimed to determine the diversity of endophytic fungi in healthy leaves of S. bicolor in periods of pre and post-flowering, collected in Goiana and Serra Talhada, Pernambuco. In the laboratory, the leaves were washed with water and soap, and with the aid of a sterile punch were made leaf discs (6 mm), then disinfected in 70% alcohol for 30 seconds and sodium hypochlorite (NaOCl) 2% for 3 minutes. Two washes with sterile distilled water were performed after disinfection. The fragments were transferred to a petri dish, in triplicate, containing malt agar plus chloramphenicol (50 mg L⁻¹) for further taxonomic identification using specialized literature for morphological analysis of the taxa. To confirmation of the taxa, the DNA was extracted and amplified and sequencing the ITS region (“internal transcribed spacer”) of the rDNA. From 1728 leaf fragments analyzed, 476 specimens of endophytic fungi were isolated including 40 morphotypes/phylotypes. Cochliobolus hawaiiensis, Colletotrichum falcatum and Epicoccum sorghi were the most frequent species. The identified species pertain to the Eurotiomycetes, Dothidiomycetes, Sordariomycetes and Mucorales. Acremonium borodinense, Arthrinium sp., Cochliobolus hawaiiensis, Engyodontium album, Epicoccum sorghi, Hypoxylon griseobrunneum, Phyllosticta capitalensis, Mucor irregularis, Mucor indicus, Mucor sp., Paraphaeosphaeria sp., Periconia macrospinosa, Purpureocillium lilacinum and Talaromyces apiculatus, are cited for the first time as endophyte to sorghum.

Thesis (M.Sc. Agriculture (Agricultural Economics) -- University of Limpopo, 2019 / Studies have indicated that sorghum hectares in South Africa have been decreasing over the past decades. This has resulted in a huge importation of the grain sorghum by the country. This study was undertaken due to sorghum production variability in South Africa. The objectives of this study were to estimate elasticity of sorghum production to changes in price and non-price factors, as well as estimating the short-run and long-run sorghum price elasticity. The study used time series data spanning from 1998 to 2016. This data was obtained from the abstracts of agricultural statistics and verified by South African Grain Information Services. Variance Error Correction Model (VECM) was employed to address both objectives. A number of diagnostic tests were performed to ensure that the study does not produce spurious regression results. This study estimated sorghum supply elasticity using two dependent variables being the area and yield response functions as model one and two respectively. The results have shown that area response function was found to be a robust model as most of the variables were significant, responsive and elastic. Maize price as a competing crop of sorghum negatively influenced the area allocation; however, the remaining variables positively influenced the area allocation in the long-run. In this model, all variables were statistically significant at 10% and 1% in the short and long-run respectively. In the yield function, most of the variables were insignificant, not responsive and inelastic, therefore, this model was found not to be robust and hence not adopted. Thus, it was concluded that sorghum output in South Africa is less sensitive to changes in price and nonprice factors. The findings further indicated that error correction term for area was -1.55 and -1.30 for yield response function. This indicated that the two models were able to revert to equilibrium. Therefore, it was concluded that the area response function was more robust, while the yield response function was not. Furthermore, it was concluded that sorghum production was more responsive to area allocation than yield function. Based on the findings, the study recommends that amongst other methods to enhance sorghum output, producers could use improved varieties or hybrids, as this action would result in allocation of more land to sorghum production, following price change.

Sorghum [Sorghum bicolor (L.) Moench] is one of the most important cereal crops grown in arid and semi-arid regions of the world. The North Eastern regions of Ethiopia are known for its high sorghum production and genetic diversity, and proneness to moisture stress. Globally, moisture stress is one of the major sorghum production constraints limiting genetic gain through breeding. Although, the importance of Ethiopia’s sorghum germpalsm has been widely recognized both nationally and internationally, the genetic potential of the germplasm has not yet been fully assessed and exploited in breeding programmes. Therefore, the objectives of this study were: (1) to evaluate sorghum production systems and patterns, major production constraints and cropping mechanisms, varietal diversification, farmers’ criteria for choosing varieties over time and space, and adoption of improved varieties, (2) to assess the agro-morphological and molecular diversity and population structure of lowland sorghum landraces collected from different geographic origins using morphological and SSR markers, (3) to assess the performance of sorghum landraces under moisture stress conditions and identify promising lines, and (4) to determine heterosis and combining ability of lowland sorghum landraces for grain yield, yield components and drought tolerance and to identify suitable parents for future hybrid cultivar development for the North Eastern Ethiopia or similar environments. A survey was conducted in the North Eastern Ethiopia sampling three Administrative Zones, six Districts and 12 Peasant Associations. Data was gathered from a total of 171 farmers and analyzed using SPSS statistical package. The results suggest that the performance of sorghum was generally poor mainly due to moisture stress, pests, diseases, weeds, farmland fragmentation due to demographic pressure, poor soil fertility, and poor performance of the local varieties. The productivity of sorghum was also largely hindered by the use of inherently poor yielding local landraces as farmers were forced to abandon their high yielding, big-headed and late maturing sorghum varieties due to the prevalence of recurrent moisture stress. The survey found that the region is as a rich source of genetic diversity and more than 70 distinct sorghum landraces were identified. The majority of the farmers grew their local landraces, despite the accessibility and availability of many improved sorghum varieties and production packages. Farmers were willing to adopt the improved varieties if they had farmers preferred attributes such as as red seed colour, tall with high biomass yield. To benefit the most from the available improved technologies, farmers have to be part of the breeding process right from the very beginning. Lowland sorghum accessions which exhibited farmer-desired traits were selected from the entire landrace germplasm collection at the national gene bank of Ethiopia. Field evaluations of the selected 278 landraces together with checks were held at Sirinka and Kobo agricultural research stations for 12 qualitative and 10 quantitative traits under stress and non-stress conditions. Two hundrad landraces were selected on the basis of their morphological distinctiveness and drought tolerance, in terms of earliness and yield stability. Molecular level diversity assessment was conducted using 30 SSR markers. Considerable magnitude of variation was observed among landraces between and within geographic origin for most of the traits studied. The morphological variability was also complemented by high molecular markers diversity. Thirty two pure lines were selected for inclusion as parents in the sorghum breeding programme for yield and drought tolerance. The selected lines were then crossed to four cytoplasmic male-sterile lines that had different cytoplasm systems (A1 to A4) using a line x tester mating design scheme. The 32 parents, together with the 128 hybrids and 4 check varieties were evaluated for grain yield, yield components traits and drought tolerance under stress and non-stress environments. Data were analysed using GenStat statistical package following a fixed effects model. Non-additive gene action was predominant in controlling plant height, grain yield, above ground biomass, grain filling duration, 100-seed weight and panicle weight, whereas additive gene action was found more important in controlling days to 50% anthesis and panicle length. Novel landraces with high GCA effects were selected including 214838-A, 242039-B, 75454, 73056-B, and 242050-A which will serve as potential parents for cultivar development. Similarly, the study identified new experimental hybrids i.e. ICSA 749 x 242039-B, ICSA 756 x 242049-B, ICSA 756 x 75454, ICSA 756 x 73059 and ICSA 756 x 214855 with high SCA effects and heterosis for grain yield which will be forwarded for further stability analysis and farmers participatory selections at representative growing environments. In general, the study identified invaluable sorghum germplasm and candidate hybrids useful for further breeding and conservation strategies. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Typescript (photocopy). / Digitized by Kansas Correctional Industries