The crop grows well in small, subsistence plots under primitive cultivation methods or as vast monocultures utilizing the most modern production practices and equipment. Early domestication of sorghum and subsequent movement too many regions of the world, especially semi-arid tropical areas, resulted in the evolution of a genetically diverse crop species. The challenge for crop protectionists is to use the genetic diversity of sorghum to combat a complex of insect pests. Sorghum is a large-stemmed tropical grass having the ability to grow to great heights. Sorghums from the varied environments ensured germplasm diversity. Sorghum improvement specialists have long recognized the restricted germplasm base of sorghum adapted for temperate areas. Plant genetic improvement efforts generally attempt to maximize yield, which result in a recombination of some genetic components and, inadvertently, in the loss of others. Intrinsic plant defense mechanisms have economical and ecological benefits. Economic benefits have been assessed for sorghum resistant to some insect pests.

Sorghum grain is generally used as food, feed or in agri-food industries in Senegal. Despite this importance, the yield remains low with gaps of more than 1 t.ha-1 compared to potentials of registered varieties. Several sorghum production limiting factors included sorghum midge. To manage this pest and reduce damage, various management methods are used. This study aimed at determining the occurrence of the midge and the duration of sorghum development of tested lines in relation to their resistance. The experiments were done during the cropping seasons of 2016 and 2017 where sorghum midge are abundant at Roff on the western side of the Senegalese Groundnut Basin. Sorghum midges began emerging in October and peaked in mid-November. Time to 50% flowering varied from 56 to 75 days. Severity of damage by midge scored between 3 and 7 for all lines. Three lines were moderately resistant to sorghum midge.

The maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), is a major insect pest of stored grain. This study evaluated resistance of grain of 26 sorghum genotypes, Sorghum bicolor (L.) Moench, to maize weevil under laboratory conditions. Three female and two male newly emerged maize weevils were reared with 5 g of grain in each of 10 vials for each of the 26 sorghum genotypes in a laboratory experiment. The weevils and grain of each genotype were scored once every 3 wk for a total of five times during 105 d. The numbers of live and newly emerged maize weevils, dead weevils from the initial population, damage score (scale of 1-5), and grain weight loss were used to indicate resistance. The least percentage weight loss of 23.9 and 24.1% was recorded for sorghum genotypes Sureño and (5BRON151*Tegemeo)-HG7, respectively. Genotypes B.HF8 and (A964*P850029)-HW6 had the most weight loss, 70.6 and 67.7%, at 105 d after infestation. Genotypes B.HF8 and (A964*P850029)-HW6 consistently exhibited the highest numbers of maize weevil, 63 and 84, per vial at 105 d after infestation. Sorghum genotypes Sureño, (SV1*Sima/IS23250)-LG15, (5BRON151*Tegemeo)-HG7, and (B35*B9501)-HD9 ranked among the top four genotypes with least damage rating more often than any other genotype across the five sampling dates. On the other hand, genotypes B.HF8, (A964*P850029)-HW6, (Segaolane*WM#322)LG2, and (Tx2880*(Tx2880*(Tx2864*(Tx436*(Tx2864*PI550607)))))-PR3-CM1 were more often ranked among the top four genotypes with the highest damage rating. Our results indicate that grain of genotype Sureno is most resistant to the maize weevil among screened genotypes.

The sorghum [Sorghum bicolor (L.) Moench] germplasm lines RTx3410 through RTx3428 (Reg. No. GP‐846 to GP‐864, PI 686993 to PI 687011) were developed and released by Texas A&M AgriLife Research, Lubbock, TX, in 2018. The lines are resistant to damage caused by the sugarcane aphid [Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae)] (SCA). All lines were developed by intentional plastic bag emasculation crosses and selected using the pedigree method of plant breeding. Resistance in RTx3410 through RTx3426 was identified after the SCA became a consistent pest of sorghum in the United States in 2013. To develop RTx3427 and RTx3428, crosses and selections were made in the Texas A&M AgriLife Research program at various Texas locations and resistance to the SCA in southern Africa was identified in Botswana and South Africa. Resistance in the United States was confirmed following identification of virulent SCA in 2013. All lines at seedling and adult plant stages expressed moderate to high levels of resistance to SCA. Resistance in RTx3412 to RTx3426 is derived either from Tx2783 or an early generation sib. Resistance in RTx3410, RTx3411, RTx3427, and RTx3248 is from unknown sources of resistance. The genetic relationship between the resistance gene(s) from the different sources is not known. The lines with potentially diverse sources of resistance provide the sorghum industry with a diversity of elite germplasm with resistance to SCA.

Background: Ancestral Puebloan black-on-white ceramics of the American Southwest can be classified as containing pigments within their painted designs containing high levels of organic-based elements such as potassium, or mineral-based elements such as iron, or a mixture of these elements. The identification of pigment elements of the pottery of a site is fundamental in determining the site's cultural and temporal context. This paper will concentrate only on the analysis of mineral based pigment which was shown by previous researchers to exhibit greater concentrations of iron than organic based pigment. Although the visual discrimination of these pigments can be difficult if the pigment is a mixture of both pigment types or if the pigment is worn, this paper will describe a sherd sample previously shown to contain only mineral pigment. For the present study, a Tescan variable pressure scanning electron microscope, a JEOL 6400 scanning electron microscope, and a Hitachi S-3400 N scanning electron microscope were used with the same sherd. This sherd was coated with ruthenium to reduce charging without the visual color change associated with sputtered metal coatings. A reduction in microscope chamber vacuum also greatly reduced charging of unpainted areas. An energy dispersive spectrometry detector produced a map of the iron present in the sherd. Areas of iron in the sherd were identified using a backscatter electron detector. Iron as well as other elements present in the paint pigment was also detected using micro-X-ray fluorescence on the same sherd.Results: The images and maps produced by the Tescan variable pressure scanning electron microscope did not always show well-defined iron-based pigmented areas on the sherd. Although the secondary image taken with a high vacuum did not show clear boundaries of the pigment on the sherd, a secondary image taken at a low vacuum of the same area showed well defined pigment boundaries. Other images taken with this microscope such as the backscatter image showed boundaries of sections of the pigment and the energy dispersive spectroscopic map showed a green colored pattern corresponding in general to the pigment area of the sherd containing iron. Using micro-X-ray fluorescence, the Hitachi S-3400 N scanning electron microscope mapped the following elements: iron, aluminum, potassium, calcium, sulfur, and silicon at a high vacuum with excellent resolution primarily for iron in the paint pigment on the sherd.Conclusions: The best resolved image of iron-based pigment for the ruthenium coated sherd was obtained using the low vacuum secondary detector in the Tescan Vega 3 XMU. Excellent resolution for the energy dispersive spectrometry maps for iron was obtained by the micro-X-ray fluorescence detector on the Hitachi S-3400 N scanning electron microscope.

Greenbug, Schizaphis graminum (Rondani), is a major insect pest of wheat and sorghum on the southern Great Plains. In this review, we outline greenbug life history and biology, describe direct and indirect crop injury to wheat and sorghum, and discuss current management strategies such as biological control, cultural control focusing on host plant resistance, monitoring, and chemical control that can be incorporated into an integrated pest management program.

Panicle caterpillars comprise an economically important insect pest complex of sorghum throughout the Great Plains of the United States, particularly in Kansas, Oklahoma, and Texas. The sorghum panicle caterpillar complex consists of larvae of two polyphagous lepidopteran species: the corn earworm, Helicoverpa zea (Boddie), and fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Sampling for panicle caterpillars in sorghum fields is usually accomplished by the beat bucket sampling technique with a fixed sample size of 30 beat bucket samples of one sorghum panicle each per 16.2 ha of field. We used Wald's sequential probability ratio test for a negative binomial distribution to develop a sequential sampling plan for panicle caterpillars. In total, 115 sorghum fields were sampled in Kansas, Oklahoma, and Texas from June to August 2010. Panicle caterpillars had an aggregated distribution of counts confirmed by Pearson's chi-square statistic for lack of fit to the negative binomial distribution for each sampled field. A sequential sampling plan was developed using a high threshold (an economic threshold) of 0.5 caterpillars per sorghum panicle, a low threshold (a safe level) of 0.20 caterpillars per panicle, and fixed error rates (alpha = 0.10 and beta = 0.05). At caterpillar densities > 0.45 and < 0.12 per panicle, the average number of panicles inspected to make a decision was less than the current recommendation of 30. In a 2013 validation test of 25 fields, the expected number of samples taken from average sample number curve was in close agreement with the number of samples required using the sequential plan (r2 = 0.93), and all fields were correctly classified when compared with a fixed sample size result. The plan improved upon current sampling recommendations for panicle caterpillars in sorghum because at known acceptable fixed error rates fewer samples were required when caterpillars are scarce or abundant, whereas more samples were required to make decisions with the same acceptable error rates when densities were near the economic thresholds.

Panicle caterpillars are economically important pests of sorghum throughout the Great Plains of the United States. Sorghum producers, crop consultants, and extension professionals desire to manage panicle caterpillars to minimize economic loss. To manage panicle caterpillars in this manner, sorghum fields must be sampled to facilitate optimal control decisions for this pest complex. The decision support system (DSS) described here contains a simple expert system to calculate the economic threshold for panicle caterpillars in any sorghum field. This article reports the development of the DSS, which is based on a knowledge representation model that is easy to use and requires no specialized training. Our web-based DSS application is accessible through most web browsers on personal computers having access to the Internet.

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Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Archaeologists have found that the elements present in the pigments used on Ancestral Puebloan black-on-white painted pottery are an important descriptive attribute. They typically describe the pigments used to produce these painted designs as either carbon-based (containing primarily organic compounds) or mineral-based (containing primarily iron compounds), although in some cases these pigments are combined or “mixed”.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

The maize weevil, Sitophilus zeamais Motschulsky, a major insect pest of stored grain, infests kernels in the field and is brought into storage where damage continues. To evaluate damage by maize weevils to different maturity stages of kernels of sorghum, Sorghum bicolor (L.) Moench, five adult weevils were put into each of 10 vials with 5 g of kernels collected from 'Pioneer 86G08' sorghum at different stages of maturity in the field. Statistically significant differences were found among the maturity stages of sorghum in the percentage of damaged kernels and numbers of live and dead maize weevils 7 days after infestation. At 7 days after infestation, 6.1, 15.4, 23.1, 17.4, 12.0, and 8.0% of the grains that had 50 (milk), 34 (soft dough), 32 (hard dough), 24, 16, and 14% moisture (physiological maturity), respectively, were damaged by maize weevils. Sorghum grain at the hard-dough stage (approximately 32% moisture) was most vulnerable to maize weevils.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.