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Two segregating generations (F₃ and F₄) from 6 × 6 half-diallel crosses, excluding reciprocals, of a sesame breeding program were exposed to natural infection by the root rot pathogen (<i>Macrophomina phaseolina</i>) in two successive seasons (2004 and 2005). There was highly significant variability in the progeny of all investigated crosses which might be a valuable tool for further breeding programs for root rot disease management. The level of infection in 2004 ranged from 2.63% (cross P₂ × P₅) to 52.42% (P₄ × P₅) in the F₃, and from 1.28% (P₁ × P₅) to 51.78% (P₄ × P₅) in the F₄. During 2005, infection varied from 1.01% (P₂ × P₅) to 50.91% (P₄ × P₅) in the F₃, and from 1.00% (P₃ × P₄) to 48.00% (P₄ × P₅) in the F₄. These crosses were ranked resistant or highly susceptible and gave seed yields per feddan (= 4200 m) of 536.67, 361.67, 641.67, and 408.33, respectively. The F₃’s and F₄’s of five crosses, i.e. P₁ × P₂, P₁ × P₄, P₁ × P₅, P₂ × P₆, and P₃ × P₄, were resistant in both segregating generations and both seasons. Such crosses might be helpful for breeding programs due to their stable resistance. Lines from the crosses P₁ × P₆, P₂ × P₄ and P₄ × P₅ could also be used for improving resistance due to an increase of inherited resistance from one generation to another. The estimated heritability showed high values in all cases and indicated that selection for these traits could be useful for breeding programs for resistance to root rot with seed yield potential. Correlation coefficients showed that there were some positive correlations such as percentage of infection by <i>M. phaseolina</i> between both generations (F₃’s and F₄’s) as well as within each generation during a season’s evaluation, i.e. 0.742, 0.976, 0.846, 0.732, and 0.987. The highest significant and positive correlations assisted in the selection of some crosses to be used in breeding programs and will aid breeders to achieve sesame cultivars with charcoal root rot resistance.

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Basal Stem Rot (BSR) is a disease caused by fungus which affect oil palm tree. This study aims to visualize the geographical distribution of BSR incidence among oil palm smallholders in Selangor using Geographical Information System (GIS) and its relationship to the type of soil series. The geographical distribution of BSR incidence of smallholders in Selangor were mapped using 168 Global Positioning System (GPS) coordinate of possible infected area. The methodology followed in finding the relationship between BSR and soil series by assigning percentage of BSR incidence based on type of soil series. Majority of the BSR incidences were found to be confined to the Selangor-Kangkong (Aeric Tropic Fluvaquent-Typic sulfuric tropic fluvaquent) soil series followed on Peat (Typic Fibric Tropohemist) soil then Kranji (Typic Sulfaquents) soil series and finally the Briah-Organic Clay and Muck (Typic Tropic Fluvaquent) soil series. Distribution pattern of the BSR revealed that most of the incidences were confined along the coastal area which might be due to the planting of oil palm in previous coconut stands. Low pH of Selangor (Aeric Tropic Fluvaquent) and Peat (Typic Fibric Tropohemist) soil series shows a higher BSR incidence while high pH of Kranji (Typic Sulfaquents) and Briah (Typic Tropic Fluvaquent) soil series shows slightly lower BSR incidence. From this study, it can be concluded that the distribution of BSR were mostly confined to the coastal areas which might be due to the planting of oil palm in previous coconut stands rather than any relationship with the type of soil series. This distribution map of BSR incidence can be used to deliver effective extension services regarding BSR to smallholders with a specified target based on location and soil series.

Fungal spore populations in the outdoor and indoor atmosphere of Ismailia have been studied during the period from Mar~:h 1992 to May 1993. A total of 23 350 cfu and 73 species were recorded. Cladosporittm cladosporioides, AureobasMium ptt/ht/ans and AspergiHus flavus were the most abundant. The indoor and outdoor mycoflora showed marked quantitative and qualitative differences. In view of count, recorded species could be categorized into three groups as follows: (a) species showing higher counts in out-than indoor, (b) species showing the opposite trend i.e. lower counts in out-door than indoor, (c) species showing approximately equal counts in out-and indoor. Regarding seasonal periodicity, March and either September or October showed the highest count for both normal fungal flora (NFF) and opportunistic fungal flora (OFF). While January and July showed the lowest count of them both, May but not July was the lowest as for outdoor NFF.