The gas exchange of the upper fully expanded leaf of the root parasite Striga hermonthica and of its host Sorghum bicolor was measured under wet and dry conditions to identify the mechanisms of the devastating effects of the parasite on its hosts under drought. The short-term water stress severely reduced photosynthetic rate in infected sorghum, but less in S. hermonthica. Soil water stress did not affect leaf respiration rate in either S. hermonthica or infected sorghum. This suggests that under dry conditions both infected sorghum and S. hermonthica decreased autotrophic carbon gain. The transpiration rate of S. hermonthica, a major driving force for assimilate uptake from the host, was higher and less affected by water stress than that of infected sorghum. Stomatal density on the abaxial surfaces of the leaves was higher in S. hermonthica than in sorghum. Both S. hermonthica infection and water stress decreased stomatal conductance of the sorghum leaves. S. hermonthica, irrespective of soil water status, had greater stomatal aperture on the adaxial and abaxial surfaces of its leaves than infected sorghum. These results indicate that the higher transpiration rate of S. hermonthica even under water stress, achieved through higher stomatal density on the abaxial surfaces of the leaves and greater stomatal aperture on both surfaces of the leaves, may induce the maintenance of water and solute transfers from the host to the parasite leading to severe damage to the host under drought.

Sorghum is an excellent alternative to other grains in poor soil where corn does not develop very well, as well as in regions with warm and dry winters. Intercropping sorghum [Sorghum bicolor (L.) Moench] with forage crops, such as palisade grass [Brachiaria brizantha (Hochst. ex A. Rich) Stapf] or guinea grass (Panicum maximum Jacq.), provides large amounts of biomass for use as straw in no-tillage systems or as pasture. However, it is important to determine the appropriate time at which these forage crops have to be sown into sorghum systems to avoid reductions in both sorghum and forage production and to maximize the revenue of the cropping system. This study, conducted for three growing seasons at Botucatu in the State of São Paulo in Brazil, evaluated how nutrient concentration, yield components, sorghum grain yield, revenue, and forage crop dry matter production were affected by the timing of forage intercropping. The experimental design was a randomized complete block design. Intercropping systems were not found to cause reductions in the nutrient concentration in sorghum plants. The number of panicles per unit area of sorghum alone (133,600), intercropped sorghum and palisade grass (133,300) and intercropped sorghum and guinea grass (134,300) corresponded to sorghum grain yields of 5439, 5436 and 5566kgha−1, respectively. However, the number of panicles per unit area of intercropped sorghum and palisade grass (144,700) and intercropped sorghum and guinea grass (145,000) with topdressing of fertilizers for the sorghum resulted in the highest sorghum grain yields (6238 and 6127kgha−1 for intercropping with palisade grass and guinea grass, respectively). Forage production (8112, 10,972 and 13,193Mg ha−1 for the first, second and third cuts, respectively) was highest when sorghum and guinea grass were intercropped. The timing of intercropping is an important factor in sorghum grain yield and forage production. Palisade grass or guinea grass must be intercropped with sorghum with topdressing fertilization to achieve the highest sorghum grain yield, but this significantly reduces the forage production. Intercropping sorghum with guinea grass sown simultaneously yielded the highest revenue per ha (€ 1074.4), which was 2.4 times greater than the revenue achieved by sowing sorghum only.

The nature and extent of growth and variability in sorghum yield is measured in this study to test the hypothesis that rapid technological change increased yield and also instability in sorghum production. Analysis is being based on 146 major sorghum producing districts of India. Annual compound growth rate of sorghum yields for different districts were computed for various periods between 1966 and 1993. Expansion of modern sorghum cultivars positively contributed to the sorghum yield. The coefficient of variation of sorghum yields was estimated for the same districts and from the same set of data after detrending. Analysis showed a general decline in yield variability over time. The coefficient of variation in sorghum yield decreases with the increase in proportion of modern sorghum cultivars. Relative variability of sorghum yield of modern sorghum cultivars, estimated from the experimental data for the period 1982?96, is less than the relative variability of other sorghum cultivars. The study concludes that modern sorghum cultivars contrihuted to the increase in yield and reduction in relative variability in yield and thereby, enhanced food security in India. It also suggests that future sorghum research in India should be emphasized on yield enhancement rather than on yield stabilization | U K Deb, P K Joshi, M C S Bantilan, 'Impact of modern cultivars on growth and relative variability in sorghum yields in India', Agricultural Economics Research Review, vol. 12(2), pp.84-106, Agricultural Economics Research Association (India), 2013

Grain sorghum is grown for consumption by both human and animals; sorghum-based diets are offered to ruminants, pigs and poultry. Sorghum is included in animal diets primarily as an energy source, being largely derived from starch. However, the efficiency of utilisation of energy from sorghum is variable and this may be problematic for animal production. Starch granules are surrounded by kafirin protein bodies and both are embedded in the glutelin protein matrix in the sorghum endosperm. Protein–starch interactions in the sorghum endosperm may limit starch hydrolysis and its availability. The digestibility of protein/amino acids in sorghum is usually inferior to the other cereal grains. Kafirin, which is the dominant protein fraction in sorghum, is poorly digested and deficient in basic amino acids, especially lysine. Sorghum contains more phenolic compounds and phytate than the other cereal grains and both phenolics and phytate may impede digestion by directly or indirectly binding with protein and starch. As considered in this review, various feed processing technologies have been evaluated to improve sorghum utilisation in pigs and poultry. Sorghum varieties with a hard endosperm tend to be more popular in breeding programmes due to their insect resistance and high yield. The texture of sorghum grains varies with the proportions of corneous and floury endosperm. The extent of particle size reduction and its uniformity following grinding is critical to growth performance in pigs and poultry. Sorghum is especially vulnerable to hydrothermal processes which markedly reduce the in vitro pepsin digestibility of sorghum proteins. Thus steam-pelleting, steam-flaking and wet-extrusion, which involve heat and moisture, may lead to undesirable physico-chemical changes in sorghum including disulphide linkage formation in kafirin protein bodies. Dry-extrusion where heat is generated by friction may enhance starch digestibility by gelatinising starch and disrupting sorghum structures without the addition of moisture. Combining reducing agents with hydrothermal processes may enhance the solubility and digestibility of sorghum protein by either cleaving disulphide linkages or preventing their formation. The inclusion of exogenous enzymes in pig and poultry diets is an established practice to improve performance of monogastric species and phytate-degrading enzymes are of particular relevance due to the relatively high phytate contents in sorghum. Additional strategies including irradiation may also have potential to enhance nutrient utilisation in sorghum. Pigs and poultry may respond differently to any strategy due to fundamental differences in gastrointestinal structure and physiology, which is particularly true of grain particle size.

Sorghum (Sorghum bicolor) is the fifth most importantcereal crop in the world. Different types of sorghum arerecognized. These are: grain sorghum, dual purpose(grain and fodder) sorghum, fodder sorghum, foragesorghum and sweet stalk sorghum. Also two types ofsorghums are noted based on the season of adaptation;these are rainy (wet) season or postrainy (dry) seasonsorghum. There are two distinct sorghum growingseasons in India, kharif (rainy season; June?October) andrabi (postrainy season; October?January). In India, thegrain productivity is about 1.2 t ha-1 in the rainy season,and about 0.8 t ha-1 in the postrainy season whereas theglobal grain productivity of sorghum is 1.4 t ha-1(FAOSTAT 2011). The grain sorghum requirements forthese two seasonal adaptations are quite diverse due todifferent agroclimatic conditions (Rana et al. 1997).There has been a significant decline in area under grainand dual purpose sorghum during the rainy season due tograin molds, but the area has remained stable in thepostrainy season where mostly dual purpose sorghumsare cultivated | B V S Reddy et al., 'Postrainy season sorghum: Constraints and breeding approaches', Journal of SAT Agricultural Research, vol. 10(1), pp.1-12, International Crops Research Institute for the Semi-Arid Tropics, 2013

Sustainable production of sorghum, Sorghum bicolor (L.) Moench, depends on effective control of insect pests as they continue to compete with humans for the sorghum crop. Insect pests are a major constraint in sorghum production, and nearly 150 insect species are serious pests of this crop worldwide and cause more than 9% loss annually. Annual losses due to insect pests in sorghum have been estimated to be $1,089 million in the semiarid tropics (ICRISAT Annual report 1991. International Crop Research Institute for Semi-arid Tropics. Patancheru, Andhra Pradesh, India, 1992), but differing in magnitude on a regional basis. Key insect pests in the USA include the greenbug, Schizaphis graminum (Rondani); sorghum midge, Stenodiplosis sorghicola (Coquillett); and various caterpillars in the Southern areas. For example, damage by greenbug to sorghum is estimated to cost US producers $248 million annually. The major insect pests of sorghum on a global basis are the greenbug, sorghum midge, sorghum shoot fly (Atherigona soccata Rond.), stem borers (Chilo partellus Swin. and Busseola fusca Fuller), and armyworms (Mythimna separata Walk and Spodoptera frugiperda J.E. Smith). Recent advances in sorghum genetics, genomics, and breeding have led to development of some cutting-edge molecular technologies that are complementary to genetic improvement of this crop for insect pest management. Genome sequencing and genome mapping have accelerated the pace of gene discovery in sorghum...

Y Huang, H C Sharma, M K Dhillon, 'Bridging conventional and molecular genetics of sorghum insect resistance', Plant Genetics and Genomics: Crops and Models, vol. 11, pp.367-389, Springer, 2013 | Sustainable production of sorghum, Sorghum bicolor (L.) Moench, depends on effective control of insect pests as they continue to compete with humans for the sorghum crop. Insect pests are a major constraint in sorghum production, and nearly 150 insect species are serious pests of this crop worldwide and cause more than 9% loss annually. Annual losses due to insect pests in sorghum have been estimated to be $1,089 million in the semiarid tropics (ICRISAT Annual report 1991. International Crop Research Institute for Semi-arid Tropics. Patancheru, Andhra Pradesh, India, 1992), but differing in magnitude on a regional basis. Key insect pests in the USA include the greenbug, Schizaphis graminum (Rondani); sorghum midge, Stenodiplosis sorghicola (Coquillett); and various caterpillars in the Southern areas. For example, damage by greenbug to sorghum is estimated to cost US producers $248 million annually. The major insect pests of sorghum on a global basis are the greenbug, sorghum midge, sorghum shoot fly (Atherigona soccata Rond.), stem borers (Chilo partellus Swin. and Busseola fusca Fuller), and armyworms (Mythimna separata Walk and Spodoptera frugiperda J.E. Smith). Recent advances in sorghum genetics, genomics, and breeding have led to development of some cutting-edge molecular technologies that are complementary to genetic improvement of this crop for insect pest management. Genome sequencing and genome mapping have accelerated the pace of gene discovery in sorghum

The purpose of this study was to evaluate the physicochemical characteristic of the cooked rice added with glutinous and non-glutinous sorghum. The sorghum cultivars were Sorghum bicolor L. Moench cv. Hwanggeumchal, Nampungchal (glutinous), and Donganme (nonglutinous), and rice cultivar was Ilpum rice. The cooking properties and pasting characteristics of cooking rice adding with sorghum according to varieties and different addition rates evaluated. The cooking properties and pasting characteristics had significant changes with the varieties and different addition rates of sorghum. With increased addition rates of sorghum, the pasting temperature, peak viscosity, trough viscosity, breakdown viscosity, and final viscosity were decreased. With increased addition rates of sorghum, the total polyphenol and flavonoid contents before and after cooked rice were increased. Total polyphenol contents of 30% addition rates before cooking rice with Hwanggeumchal, Nampungchal, and Donganme sorghum were 1,693.30, 1,890.98 and 2,386.11 μg/g sample, whereas those after cooking rice with sorghum were 1,189.28, 1,190.42 and 1,397.87 μg/g sample, respectively. The high level of DPPH radical scavenging activity before and after cooking rice with sorghum were 126.29 and 70.58 mg TE/100g sample in the Donganme in 30% addition rates. Also, ABTS radical scavenging activity was 135.56 and 83.12 mg TE/100g sample, respectively. The results of this study show that the addition of sorghum can make cooked rice improved antioxidant activity.

To study the N response of sorghum (Sorghum bicolor) intercropped with pigeon pea (Cajanus cajan), 3 experiments were conducted in Vertisols. In experiment 1, sole sorghum (180 000 plant/ha), sole pigeon pea (40 000 plants/ha) and 3 intercrop population treatments (40: 40, 80: 80 and 120: 120% of sole optimum) were sown as main plots with 4 levels of N (0, 40, 80 and 120 kg/ha) only to sorghum as subplots. It is concluded that intercropped and sole sorghum responded similarly to applied N. Different sorghum populations in the intercrop performed similarly. Pigeon pea did not seem to be contributing any N to its companion sorghum. Sorghum at higher N levels had a greater effect on pigeon pea yield. Both crops did equally well at 45 cm and 90 cm when grown as sole crops | T J Rego, 'Nitrogen response studies of intercropped sorghum with pigeonpea', pp.210-216, 2013

Sorghum midge, Stenodiplosis sorghicola (Coquillett), is one ofthe most important pests of grain sorghum worldwide. Sorghum midge adultsemerge in the morning, mate at or near the site of emergence, and then thefemales proceed in search of sorghum crop at flowering for oviposition, andsome visual and odor stimuli play an important role in host finding and ovipositionprocess. We used a glass apparatus with two (Y-tube) arms to studythe orientation of sorghum midge females to visual and odor stimuli underlaboratory conditions. Most sorghum midge females were attracted to yellow(30%), followed by green (26%), red (23%), and blue (10%). Sorghum midgefemales responded more quickly to yellow, followed by red, green, and blue.However, under dual-choice conditions, differences in numbers of sorghummidge females attracted to yellow versus green, red versus blue, and blueversus green were not significant. More sorghum midge females were attractedto sorghum panicle odors plus red (47%) or yellow (40%) colors than to hostodors alone (31%). Information on the color preference of sorghum midge femalescould be exploited for developing suitable traps to monitor its abundancein combination with kairomones or pheromones | H C Sharma, B A Franzmann, 'Orientation of Sorghum Midge, Stenodiplosis sorghicola, Females (Diptera: Cecidomyiidae) to Color and Host-Odor Stimuli', Journal of Agricultural and Urban Entomology, vol. 18(4), pp.237-248, South Carolina Entomological Society, 2013