The condition of soil and microclimate are prerequisite for proper growth and development of a plant. The environment may be mediated by artificial filming with different colored polyethylene. The mechanism of lettuce growing under colored plastic film remains largely unknown. Thus, to investigate the impact of different plastic film on the growth environment, yield parameters and phytochemical properties of lettuce, the present study was performed. Five different colored polyethylene films viz. black, white, blue, olive and silver were used as a treatment factor, in filed condition. The results demonstrated that the soil pH, temperature and overall performance of lettuce, as well as the phytochemical composition, varied within the use of different films. The maximum soil pH and temperature were found under black filming plots. Additionally, the black colored plastic film exhibited the best values for most of the yield parameters studied over other plastic films, whereas the field with non-plastic film condition showed the worst data in the experiment. Phytochemical concentrations and nutritive value of lettuce were also significantly affected by the colored plastic treatments. Furthermore, the chlorophyll, anthocyanin, phenols and carotenoids contents were increased in plants grown in soil covered with black polyethylene. Vitamin C content was of 2.5 fold higher in the plants grown in the black film compared to control conditions. The application of plastic film led to elevated concentrations of macro and micronutrients in lettuce because of the direct effect of modified radiation under the plastic film. Taken together, it can be concluded that plastic filming could be used to enhance the yield and nutritional status of lettuce in natural plant production facilities.

Yield, Dry Matter, Specific Gravity and Color of Three Bangladeshi Local Potato Cultivars as Influenced by Stage of Maturity

The aim of this study was to evaluate the grafting compatibility of different varieties of tomato (Solanum lycopersicum L.) scions on potato (Solanum tuberosum L.) rootstocks to develop a ‘pomato’ plant. In this study three potato varieties; Diamant (P1), Cardinal (P2) and Asterix (P3), and two tomato varieties; Bangladesh Agricultural Research Institute (BARI) tomato-2 (T1) and BARI tomato-11 (T2) were used to make the grafted combinations T1P1, T1P2, T1P3, T2P1, T2P2 and T2P3, designated G1, G2, G3, G4, G5, and G6, respectively. Tomato seedlings aged 25 (S1) and 35 days (S2) were selected as scions. Graft compatibility was analyzed based on the growth and yield of the pomato plants. The results revealed that varieties and scion age had a significant effect on the pomato fruit and tuber yield. The initiation of flowering was not affected by the various graft combinations; however, plant height, leaf number, branch number, number of clusters per plant, number of fruit per cluster, number of fruit per plant, fruit length, fruit diameter, single fruit weight and total fruit yield per plant were higher in G5S1 among the combinations. On the other hand, the number of tubers per plant, single tuber weight, and tuber yield per plant were highest for a few combinations. Overall, it was concluded that Cardinal (P2) and Asterix (P3) potato were the most compatible for grafting with BARI tomato-11 (T2) at the scion age of 25 days (S1), based on vegetative growth and fruit and tuber yield of pomato plants.

Organic production of Green Cabbage may ensure the nutritional status and food safety for the consumers, but maintaining the productivity and economic viability of inorganic production is almost impossible for farmers of Bangladesh. At this context, a study was carried out at the Horticulture farm of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during the period from October 2017 to March 2018 to evaluate the efficacy of vermicompost and biochar on agronomic properties and economic of cabbage. Four biochar treatments, ( B0: 0 t ha-1 biochar, B1 :2 t ha^-1 , B2 :6 t ha^-1 and B3 :10 t ha^-1) and three vermicompost treatments (Vc0 : 0 t ha^-1, Vc₁ :4 t ha-1 and Vc₂ :8 t ha^-1 ) were selected. B₀Vc₀ was considered as control. The results revealed that maximum highest plant height, number of leaves plant-1, leaf length, leaf breadth and plant spread were obtained when the B₃ was mixed withVc₂. But the thickness of head (10.29 cm), diameter of head (16.66 cm), % dry matter of cabbage (14.93%), weight of cabbage head plant^-1 (1370 g) and yield of cabbage (52.75 t ha^-1) were obtained from the treatment combination of B₂Vc₂. In terms of economic sustainability, the net return (Tk 523598) with highest BCR (3.70) was obtained from the treatment combination of B₁Vc₁.These results provide prove the effectiveness of biochar and vermicompost in sustainable Cabbage production. It also provides baseline guidelines for further investigation of choosing the appropriate combination of organic amendments based on crop requirement to maximize economic value. Asian Australas. J. Biosci. Biotechnol. 2021, 6 (2), 68-74

Red amaranth (Amaranthus tricolor) was grown in tunnels covered with partially UV-blocking films (<340, <350, <360, and <400 nm) for five weeks after sowing, and plant growth, anthocyanin concentration, and insect burden were compared with those of UV-transmitting films and outdoors. The values of plant height, stem cell length, leaf area, and fresh weight were higher in the plants grown under higher UV-blocking conditions, while the plant dry weight was greater under lower UV-blocking conditions due to the lower dry matter percentage under higher UV-blocking conditions. The red color of the upper leaves became lighter as the UV-blocking rate increased, while there was no such distinct difference in either the lower leaves or stem. Anthocyanin concentrations of both the stem and leaves of the plant apex were significantly lower under UV-blockings than under UV-transmitting conditions and outdoors, but there was almost no significant difference among different UV-blocking rates. Yellow and blue sticky traps were also suspended at the center of the tunnels, and twelve insects were trapped during the experimental period. The maximum invasion by insects and feeding damage of the seedlings were observed outdoors, followed by plants grown under UV-transmitting conditions. Partially UV-blocking conditions significantly reduced invasion by insects and feeding damage of the seedlings compared to outdoors and under UV-transmitting conditions, but there was no significant difference among different UV-blocking rates. The number of herbivores tended to decrease as the UV-blocking rate increased, while that of predators was little affected by the UV-blocking rate. Our results showed that partially UV-blocking conditions were as effective as fully UV-blocking conditions, especially for controlling some herbivores such as aphids and white fly, and also for maintaining an advantageous balance between herbivores and predators. On the other hand, anthocyanin pigmentation of higher plant parts was often inhibited under UV-blocking conditions.