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The chromosome constitutions of eight wheat streak mosaic virus (WSMV)-resistant lines, three of which are also greenbug resistant, derived from wheat/ Agropyron intermedium/Aegilops speltoides crosses were analyzed by C-banding and in situ hybridization. All lines could be traced back to CI15092 in which chromosome 4A is substituted for by an Ag. intermedium chromosome designated 4Ai-2, and the derived lines carry either 4Ai-2 or a part of it. Two (CI17881, CI17886) were 4Ai-2 addition lines. CI17882 and CI17885 were 4Ai-2-(4D) substitution lines. CI17883 was a translocation substitution line with a pair of 6AL.4Ai-2S and a pair of 6AS.4Ai-2L chromosomes substituting for chromosome pairs 4D and 6A of wheat. CI17884 carried a 4DL.4Ai-2S translocation which substituted for chromosome 4D. CI17766 carried a 4AL.4Ai-2S translocation substituting for chromosome 4A. The results show that the 4Ai-2 chromosome is related to homoeologous group 4 and that the resistance gene(s) against WSMV is located on the short arm of 4Ai-2. In addition, CI17882, CI17884, and CI17885 contained Ae. speltoides chromosome 7S substituting for chromosome 7A of wheat. The greenbug resistance gene Gb5 was located on chromosome 7S.

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Fruits of banana (Musa spp) cultivar 'Grand Naine' were harvested at physiological green mature stage. The fi rst lot of fruit was exposed to ethylene gas (100 ppm) for 24 h in ripening chamber. The second lot was treated with different concentrations of aqueous solution of ethephon (250, 500, 750, 1000 ppm) each for 5 min. The fruits were packed in plastic crates and stored in ripening chamber maintained at 16-18°C and 90-95% RH. Treatment with ethylene gas (100 ppm) or ethephon (500 ppm) resulted in adequate ripening of fruits after 4 days with uniform colour, pleasant fl avour, desirable fi rmness and acceptable quality and better shelf-life. The untreated control fruits were hard textured and poor in colour and quality. The ripening with ethylene gas or ethephon treatment seems to hold promise in reducing postharvest losses and boosting the economy of banana growers and traders.