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An experiment was conducted to evaluate the effects of NAA (0, 25, 50 ppm) at varying nitrogen levels (0, 50, 75, 100 % of the recommended dose) on nitrogen (N), phosphorus (P) and potassium (K) uptake by shoot and root and percentage of total NPK uptake by BARI Gom-26 at flowering and grain filling stage. Application of NAA at varying nitrogen levels had significant effect on P and K uptake by shoot and root at both stages, whereas, the N content of shoot at flowering stage and of root at the grain filling stage were non-significant.At both the stages, K content of root increased following all the treatments. At flowering and grain filling stage, P content of root and shoot increased and decreased due to different treatments. The maximum percentage of total NPK uptake was recorded from K followed by N and P respectively at both stages. In majority cases there was a decreasing trend in percentage uptake of N and P at grain filling stage compared with flowering stagewhereas, the trend was almost reverse in case of K. The N content of grain increased following all the treatments, the maximum being due to 25 ppm NAA in combination with 75 % N-fertilizer. Only decrease in P content of grain was recorded when 25 ppm NAA without any N-fertilizer was applied. In case of K content, 50 ppm NAA without any N-fertilizer resulted the only decrease. The highest nitrogen use efficiency (NUE) by total plant was also recorded from 50 ppm NAA in combination with 50 % N-fertilizer at flowering stage, whereas, from 25 ppm NAA in combination with 75 % N-fertilizer at grain filling stage.J. Asiat. Soc. Bangladesh, Sci. 42(1): 69-76, June 2016

Rice yield is severely affected by high-salt concentration in the vicinity of the plant. In an effort to engineer rice for improved salt tolerance Agrobacteriummediated transformation of rice cv. Binnatoa was accomplished with the Pennisetum glaucum vacuolar Na ? /H ? antiporter gene (PgNHX1) under the constitutive CaMV35S promoter. For the molecular analysis of putative transgenic plants, PCR and RT-PCR were performed. Transgenic rice plants expressing PgNHX1 showed better physiological status and completed their life cycle by setting flowers and seeds in salt stress, while wild-type plants exhibited rapid chlorosis and growth inhibition. Moreover, transgenic rice plants produced higher grain yields than wild-type plants under salt stress. Assessment of the salinity tolerance of the transgenic plants at seedling and reproductive stages demonstrated the potential of PgNHX1 for imparting enhanced salt tolerance capabilities and improved yield.

A field experiment was conducted to evaluate the effect of TIBA (0, 10, 20, 50 and 100 ppm) on the growth and yield attributes of BARI Chola-7 laid out in RBD. Foliar application of TIBA at flower initiation stage, decreased plant height significantly with increasing concentrations of TIBA. Number of branches and leaves per plant were found to increase from 21 and 14 days after spray (DAS) onwards, respectively due to all the TIBA treatments and the maximum number of branches and leaves per plant were recorded due to 100 ppm TIBA which was statistically at par with 20 and 50 ppm TIBA. Dry matter per plant was recorded maximum from 21 DAS up to harvest due to 20 ppm TIBA. Except 100-seed weight, other yield contributing characters viz. number of seeds per plant, yield per plant, yield per hectare were also found to maximum due to 20 ppm TIBA treatment. The highest harvest index was recorded from 20 ppm TIBA.