The study looked at how photosynthesis in pineapple guava plants changes throughout the day. They used a special device to measure different factors like light, humidity, and temperature to see how they affect photosynthesis. The results showed that the plants had two peaks in photosynthesis, one in the morning and one in the afternoon, with a dip at noon. Humidity was the most important factor affecting photosynthesis, while factors like temperature, light, and certain plant processes also played a role. The researchers found a formula that predicts how these factors influence photosynthesis in the plants.