Five parent populations of faba bean, differing in reaction to rust disease, were crossed to prepare a complete diallel of F1 hybrids. Detached leaves of the parents and F1 hybrids were challenged with 3 Australian rust populations and symptom development was monitored from 11 to 16 days after inoculation, using a disease score related to the percentage of leaf area covered with pustules, and a nominal value for pustule size. Additive gene action was very important in determining the response to rust disease, with ILB 3025 and ILB 3107 having similar low disease scores, Fiord and Acc 327 having high values, and Icarus an intermediate value. Cytoplasmic effects were also critical, with ILB 3025 having the most susceptible cytoplasm and ILB 3107 the most resistant, and this was most readily detected in terms of the size of the pustule. Heterosis conferred slightly lower disease scores and dominance was significant but of lesser importance than additive gene action, particularly for disease score. Rust population host gene action interactions were significant by the end of the observation period, but were much smaller than the main effects. The hybrid ILB 3107 ILB 3025 had less disease development than either parent, indicating the potential for developing more resistant cultivars using transgressive segregation. ILB 3107 shows particular promise for use as a female line as it had both nuclear and cytoplasmic factors to contribute to the development of resistant cultivars.

Degree of browning, firmness, sensory properties and microbiological quality of minimally processed immature jakfruit were investigated on initial and seventh day after storage at 5-7°C. Samples were pretreated with 0.5 % and 1 % sodium metabisulphite, 1.5 % citric acid+1.5 % ascorbic acid, 3 % citric acid, 3 % ascorbic acid and packed in polystyrene packages and over wrapped with polyvinylchloride (PVC) stretch film before storage. When degree of browning in relation to absorbance was assessed, immature jakfruit pretreated with 1.5 % citric acid+1.5 % ascorbic acid showed the lowest absorbance at 420 nm among all pretreated samples indicating low browning in samples. At 450 nm, minimally processed immature jackfruit samples pretreated with 1.5 % citric acid+ 1.5 % ascorbic acid showed the highest reflectance (indicating lowest absorbance) compared to other treatments. Variations in firmness were observed after treatment. Microbial counts were within safe-to-consume limits while coliforms were not detected in any of the samples. Erwinia aphidicola and Bacillus subtilis were identified from minimally processed immature jakfruit samples using molecular tools. 1.5 % citric acid+1.5 % ascorbic acid, 1 % sodium metabisulphite and 3 % citric acid were relatively more successful in retaining acceptable sensory quality of jakfruit even after 7 days of storage. Above pretreatments could be recommended during minimal processing of immature jakfruit meant for local sale in supermarkets where cold storage is available.

Fresh cut (minimally processed) cooking banana variety Alukesel was subjected to different pretreatments, packed in polystyrene packages and stored at 5-7 °C for a week. Effect of several identified pre-treatments on Total Plate Count (TPC) and Total Yeast and Mould counts (TYM) were evaluated. Bacteria isolated from plates were identified using biochemical tests and molecular tools. In pre-treated samples, microbial counts were within safe-to-consume limits. Bacillus cereus, Enterobacter ludwigii and Bacillus thuringiensis were identified from fresh cut samples using molecular tools. Citric acid at 3% w/v effectively controlled bacteria, yeasts and moulds and this observation was significantly different from the control (p<0.05). The present study has shown that 3% citric acid was the most effective pretreatment for minimal processing of Alukesel which controlled bacteria, yeasts & moulds completely. Alukesel pretreated with 3% citric acid was free from food borne pathogens such as Salmonella, Clostridium, Yersinia, and Listeria.

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