An investigation was undertaken with a view to observing the performance of two heat-tolerant varieties of tomato under polytunnel with and without plant growth regulator application during the summer rainy season. The present study was laid out in a Randomized Completely Block Design (RCBD) with three replications. Two heat-tolerant tomato varieties Bangladesh Agriculture Research Institute (BARI) Tomato-4, and BARI Hybrid Tomato-4 with and without plant growth regulator applications were included in this experiment. The larger fruit set percentage (42.52%) was observed from BARI Hybrid Tomato-4 which was also larger in case of pollen viability (42.75%), the figure of fruits every cluster (3.01), figure of fruits every plant (12.70), and yield every plant (460 g). Better yield was showed in spraying of 4-CPA at 40 ppm concentration in respect of percent fruit set (45.38%), figure of fruits every plant (16.45), and yield (39.39 t/ha) under high-temperature condition. In integrate treatment, BARI Hybrid Tomato-4 with 40 ppm 4-CPA performed a significant role in the figure of fruits every cluster (3.41), figure of fruits every plant (22.48), figure of fruits every plot (144.00), yield every plant (621.68 g), yield every plot (15.23 kg) and above all fruit yield (50.57 t/ha). This indicates that there is a bright scope of tomato production during summer through with and without plant yield regulator application, though the application of plant growth regulator had a positive impact on tomato yield.
APPLICATION OF PLANT GROWTH REGULATOR AND POTASSIUM NITRATE TO IMPROVE THE QUALITY AND YIELD IN WASHINGTON NAVEL ORANGES (Citrus sinensis)
