Inheritance of Resistance to Striga in Sorghum Genotype SRN39

Striga hermonthica (Del.) Benth., a parasitic weed of grasses, causes major yield reductions in the principal cereal crops of semi-arid Africa. Cultivar resistance is the most economic control measure, since adapted, resistant cultivars can be grown without additional input from the subsistence farmer. Information on the genetics of resistance to S. hermonthica is scant. This is partially attributable to the rarity of germplasms which exhibit stable resistance across geographical regions. The objective of this study was to determine if the stable resistance observed in sorghum [Sorghum bicolor (L.) Moench] cultivar SRN39 is heritable. Crosses were made between SRN39 and a susceptible parent, P954063. Parental, F1, F2 and backcross generations were grown in infested pots and development of both host and parasite was monitored. Significant variation among genotypes was observed for both host traits and effects on parasite populations. The F1 did not differ significantly in Striga resistance from the susceptible parent, suggesting recessive inheritance. However, hybrid vigor was exhibited by the F1 which yielded and developed as well as the resistant parent. Broad sense heritability ranged from 0.23 to 0.55 for host traits and from 0.10 to 0.43 for effect of genotypes on the Striga population. Joint scaling tests showed that observed variation in each host or parasite trait consisted of additive and dominance components, suggesting possible progress could be made with appropriate selection scheme

Research into Germination of Striga Seed by Sorghum Root Exudates

This research was undertaken to develop a laboratory assay to permit screening of sorghum lines for low production of sorgoleone, the first germination stimulant of Striga seed to be isolated from host root exudate. Our findings led us to assay for the other substances in sorghum root exudate which control germination of Striga seed. A convenient petri disch assay, described elsewhere, permits host selection for low stimulation of germination. Work to isolate, assay and characterize these compounds is underway at Purdue Universit

Proceedings of the West African Hybrid Sorghum and Pearl Millet Seed Workshop

Sorghum and pearl millet are the most important cereal crops in West Africa where they provide 70% of total cereal production that provide the major complements in the diets of people in the region. Research progress in the improvement of sorghum and millet is, therefore, of vital importance to the well being of people in West Africa. The Hybrid Sorghum and Pearl Millet Seed Workshop in West Africa is the culmination of the research and development effort by the Institut National de Recherches Agronomiques du Niger (INRAN) , the International Sorghum and Millet Collaborative Research Support Program (INTSORMIL), and the International Crop Research Institute for the Semi-arid Tropics (lCRISAT) during the last 10 years. The workshop served as a forum for documenting experience gained in the development, release, and diffusion of NAD-l as the first commercial sorghum hybrid in Niger. It marked a significant milestone in the history of agriculture for Niger and possibly for West Africa. The workshop brought together sorghum scientists from throughout Africa, the United States, India, and Europe. Mr. B.R. Barwale, the 1998 recipient of the World Food Prize who is credited for laying the foundation of the seed industry in India also attended the meeting and shared his experience with a paper entitled Hybrid Seed Experiences in Developing Countries

Sorghums of the Sudan: analysis of regional diversity and distribution

Sorghum [Sorghum bicolor (L.) Moench] is a very important crop in the Sudan serving as a primary source of food, beverage, and total livelihood for millions of people in the country. The crop originated in the Northeast quadrant of Africa, and the Sudan is widely recognized as a major centre of diversity. Although Sudanese sorghum germplasm has been assembled and stored over the last 50 years, careful analysis of this valuable germplasm has not been made. The objectives of this study were to assess phenotypic diversity and compare pattern of distribution among Sudanese sorghum landraces collected from different geographical regions. Phenotypic diversity among landraces was high, as expressed by the large range of variation for mean quantitative traits and the high (0.81) Shannon-Weaver diversity index. Landraces from Gezira-Gedarif tended to be shorter in stature, earlier in maturity and less sensitive to changes in photoperiod. They also had long, narrow and compact panicles that may result from adaptation to low rainfall and early adoption of mechanized farming practices. In contrast, taller and later maturing plant types characterized sorghums from Equatoria, most of which delayed their flowering in response to increased day-length. These sorghums included many genotypes with small and light kernels. Collections from Kassala showed a higher frequency of landraces with kernels that were more difficult to thresh. Landraces from Blue Nile tended to have greater agronomic eliteness with higher proportion of landraces with white kernels, poorly covered and that were easy to thresh. Sorghums from the Upper Nile tended to have loose panicles with poorly covered kernels that may result from adaptation to high rainfall of the Southern region. Although distinct distributions of types were represented by geographical origin, a high level of within-region diversity was present among all Sudanese sorghums

Hoosiers’ Health in a Changing Climate: A Report from the Indiana Climate Change Impacts Assessment

In the coming decades, Indiana’s changing climate will bring with it higher temperatures, longer heat waves, more extremely hot days and more frequent extreme storm events. Those changes will affect the health of Hoosiers in every part of the state. This report from the Indiana Climate Change Impacts Assessment (IN CCIA) describes historical and future climate-related health impacts that affect Hoosiers

Does abscisic acid affect strigolactone biosynthesis?

Strigolactones are considered a novel class of plant hormones that, in addition to their endogenous signalling function, are exuded into the rhizosphere acting as a signal to stimulate hyphal branching of arbuscular mycorrhizal (AM) fungi and germination of root parasitic plant seeds. Considering the importance of the strigolactones and their biosynthetic origin (from carotenoids), we investigated the relationship with the plant hormone abscisic acid (ABA). Strigolactone production and ABA content in the presence of specific inhibitors of oxidative carotenoid cleavage enzymes and in several tomato ABA-deficient mutants were analysed by LC-MS/MS. In addition, the expression of two genes involved in strigolactone biosynthesis was studied. * • The carotenoid cleavage dioxygenase (CCD) inhibitor D2 reduced strigolactone but not ABA content of roots. However, in abamineSG-treated plants, an inhibitor of 9-cis-epoxycarotenoid dioxygenase (NCED), and the ABA mutants notabilis, sitiens and flacca, ABA and strigolactones were greatly reduced. The reduction in strigolactone production correlated with the downregulation of LeCCD7 and LeCCD8 genes in all three mutants. * • The results show a correlation between ABA levels and strigolactone production, and suggest a role for ABA in the regulation of strigolactone biosynthesis