Abstract
The effects of Paclobutrazol (PBZ) on fruit yield of tomato (Lycopersicon esculentumMill.) were investigated by spraying it on tomato seedlings grown in an open field. The treatments were 5 x 2 factorial combinations including five rates of PBZ (control, 1 kg ha-1, 2 kg ha-1, 3 kg ha-1and 4 kg ha-1) and two times of application (at 2 to 4 and 6 to 8 true leaf growth stages of tomato seedlings), arranged in a Randomized Complete Block Design, each treatment replicated three times. The objective of the study was to characterize the effect of rate and time of application of PBZ on the yield and yield related parameters of tomato. Time and rate of application of PBZ significantly increased harvest index, yield concentration and index of economic earliness, and decreased fruit set percentage, pericarp thickness, fruit diameter and percentage of class one fruit. Irrespective of the time of application, an increase in the rate of PBZ compared to the control significantly increased days to fruit maturity. Time and rate of application of PBZ were significantly interacted to increase; unmarketable fruit yield but decrease means fruit weight. Compared to the control, the interaction effects also produced two significant trends of variations on fruit yield per plant, fruit dry weight per plant, marketable fruit yield and total fruit yield. Significant reduction in yields was observed for diluted concentrations like 1 and 2 kg/ha a.i. of PBZ in the second time of application and 1 kg/ha a.i. of PBZ in the first time of application, whereas all other treatments produced significantly higher yields than the controls. On the contrary, time and rate of application of PBZ were found to be effective in improving economic earliness of tomato. As a whole, time and rate of application of PBZ resulted in two significant trends of variations (increasing and decreasing) on fruit yields of tomato. Hence, it could be possible to propose that more assimilate reallocation to the fruits are significant advantage of PBZ treatments contributing to the improvement of seedling quality at planting for increased seedling survival rate, better stress protection, early and more fruit production.
Highlights
The cultivated tomato (Lycopersicon esculentum L Mill) belonging to the family Solanaceae is an important vegetable crop in the world
The number of primary branch per plant of tomato was significantly affected by the interaction effect of rate and time of PBZ application (Table 1)
The results show that unmarketable fruit yields are significantly increased with an increase in the rate in both application stages that could be due to the reduction in fruit size in response to the treatment
Summary
The cultivated tomato (Lycopersicon esculentum L Mill) belonging to the family Solanaceae is an important vegetable crop in the world. Its fruit is very popular among solanaceous vegetables used as a source of minerals and vitamins in the diet of all continents [1]. It ranks first in production among the most important vegetable crops in many countries. It is among the most important vegetable crops in Ethiopia [8]. Tomato production in Ethiopia was characterized by seasonality and low yield. The use of varieties, which are late maturing and low yielder, was one of the chief production constraints of Ethiopian tomato production [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
