Effect of bio regulators on flower and fruit drop control in tomato. (Solanum lycopersicum L.)
Abstract
The present investigation was carried out at Vegetable Research Farm of Dr. cRajendra Prasad Central Agricultural University, Pusa, Samastipur, Bihar, during 2019-20 research the impact of bio-regulators on plants (NAA and GA3) on morphological, flowering, physiological, yield and yield attributing and biochemical parameters of tomato using cultivar “Kashi Vishesh”.
With seven treatments and three replications, the experiment was set out in Randomized Block Design (RBD). Treatments consist of different levels of NAA (T1@ 10 ppm, T2 @ 20 ppm, and T3@ 30 ppm), GA3 (T4 @ 50 ppm, T5 @ 100 ppm, and T6 @ 150 ppm) along with control (T7 @ sprayed only distilled water). These different concentrations of NAA and GA3 were sprayed on the crop at 25, 50, and 75 days after transplanting to study the different parameters at all successive stages of crop growth.
The outcome stated that the morphological parameters were greatly affected by different levels of NAA and GA3 at all the successive growth stages except at 25 days after transplanting. Treatment T3 (NAA @ 30 ppm) produced maximum plant height, number of branches per plant, and number of leaves per plant which were at par with
treatment T5 (GA3 @ 100 ppm) at 50 and 75 days after transplanting respectively. The minimum plant height, number of branches per plant, and number of leaves per plant were observed with treatment control i.e. T7 (only distilled water) at 50 and 75 days after transplanting respectively.
All flowering and physiological parameters were also greatly influenced by the application of growth regulators (NAA and GA3). Minimum days to 50 % flowering (56.32 %), maximum number of flowering branches per plant (10.58), maximum number of flowers per plant (49.95), maximum leaf area index (3.203), maximum relative water content (1.473 %) and maximum shelf life (21.11 days) were recorded with treatment T5 (GA3 at 100 ppm).
Yield and yield attributing parameters such as minimum fruit drop percentage (0.44 %), maximum number of fruit set per plant (67.22 %), maximum number of fruits per plant (29.44), maximum equatorial diameter of fruit (5.177 cm), maximum polar diameter of the fruit (4.957 cm), maximum average yield per plant (2.637 Kg), maximum yield per hectare (29.06 t/ha), were also recorded with the treatment T5 (GA3 at 100 ppm). Biochemical parameters like minimum ABA (0.018 %), maximum TSS content of the fruit (4.8130 Brix), minimum acidity of the fruit (0.420 %), and maximum ascorbic acid content of the fruit (11.660 mg/100g) were also recorded with the treatment T5 (GA3 at 100 ppm). Maximum values of fruit drop, ABA, and acidity of the fruit percentage and minimum values of rest parameters were recorded with the treatment T7 (only distilled water). Maximum (2.69) benefit-cost ratio was also recorded with the treatment T5 (GA3 at 100 ppm) and minimum (1.67) with the treatment T7 (only distilled water).
It may be concluded that in subtropical climate, farmers face flower and fruit drop problem due to high temperatures in kharif and late kharif season, to overcome that problem they can use plant growth regulator GA3 @ 100 ppm to increase flowering, fruit set, fruit size and control the fruit drop.