The study was conducted in three sub-districts of Gazipur district in Bangladesh. It identified the diversity and distribution of tree species and which vegetable crops are grown beneath them, uses of different plants, to identify the problem faced by the farmers. Total of 43 tree plant species are used for fruit and timber were identified in the study area. Based on diversified uses, the major fruit species were jackfruit, mango and coconut. The major timber species were koroi (Albizia procera), raintree (Samanea saman), neem (Azadirachta indica), teak (Tectona grandis) and eucalyptus (Eucalyptus sp.). Total income was found to increase with increase of farm size. A large number of vegetables (32 species) are cultivated in the study area, largely for local consumption. The study showed that stem amaranthus, indian spinach, aroids, sweet gourd, chili pepper, turmeric, eggplant, and radish were grown under shade of jackfruit, mango, date palm, litchi, mahogany, and drumstick trees. The total income from trees in the last five years was higher in the large farm category than that in the tenant category. The major problems faced by the farmers in tree establishment were damage caused by animals which was reported by 68% of the respondents.
Lutfor S. Rahman* and Farid A. Mir
A.S.A. Rahman, D.J. Huber, and J.K. Brecht
Bell pepper (Capsicum annum var. Jupiter) fruit were exposed to 1.5% O2 for 1 to 5 days at 20C to examine whether the low-O2-induced poststorage respiratory suppression (PRS) in whole fruit could be due to limitations in mitochondrial oxidative capacity. Mitochondrial oxidative capacity was not affected after storing bell peppers for 1 day in 1.5 % O2. Extending the storage period from 1 to 5 days in 1.5 % 0, resulted in PRS of CO2 production for about 55 hours after transfer to air, and a marked reduction in the oxidative capacity of isolated mitochondria. Mitochondrial activity was suppressed for 10 hours after transfer to air but, within 24 hours, bad recovered to values comparable to those of mitochondria from fruit stored continuously in air. Storing bell peppers in 1.5% O2 for 5 days resulted in a reduction in the respiratory control (RC), while ADP/O ratios were not affected. The reduction was temporary since the RC attained normal activity after returning bell peppers to air. Cyanide-sensitive cytochrome and CN-insensitive pathways were suppressed after storing fruit in 1.5 % O2 for 5 days. After returning fruit from a low-O2 atmosphere to air, the alternative pathway recovered at a greater rate than the cytochrome pathway.
S.M. Lutfor Rahman, Wayne A. Mackay, Eiji Nawata, Tetsuo Sakuratani, A.S.M. Mesbah Uddin, and Bruno Quebedeaux
Effects of water stress on superoxide dismutase (SOD) activities, changes in protein content, leaf water potential (Ψl) and growth were studied in drought-sensitive Kyokko (KK) and Ratan (RT), and drought-tolerant TM 0126 (TM) and VF-134-1-2 (VF) cultivars of tomato (Lycopersicon esculentum Mill.) in order to obtain fundamental information for breeding drought tolerant cultivars that may be adapted to water stress in many parts of the world. Growth of drought-tolerant TM and VF was greater than that of drought-sensitive KK and RT under water stress conditions. Leaf water potential (Ψl) decreased by water stress treatments in all the cultivars, but the reduction was much more rapid and pronounced in KK and RT than VF and TM. Ψl of stressed cultivars decreased by 30% to 40% compared to the untreated control cultivars. The initial reduction in the range of 20% to 35% was more rapid in KK and RT than TM and VF. SOD activities were increased by water stress in all cultivars. Increase of SOD activities by water stress was much more rapid and pronounced in TM and VF than in KK and RT. Leaf protein concentration was decreased by the water stress treatments in all cultivars evaluated. In KK and RT, much more rapid reductions in protein concentration were observed than in TM and VF. The regression analysis of Ψl and SOD suggest the possibility to using SOD activities as an additional screening criterion for tomato drought tolerance improvement.