Response of prohexadione calcium and paclobutrazol on growth and physio-chemical characteristics of pear cv. Clapp's Favorite

Abstract

The present investigation was conducted to study the response of growth retardants on pear cv. Clapp's Favorite during the year 2015–2016. The experiment was laid out with thirteen treatments replicated thrice on 12 year-old-trees with uniform vigour and health under uniform cultural practices. The treatment comprises of single spray and double spray of growth retardants (prohexadione calcium @ 100, 200 and 300 ppm and paclobutrazol @ 100, 200 and 300 ppm). The first spray of growth retardants was applied at petal fall stage and second spray was four weeks after first spray. The plants sprayed twice with prohexadione calcium @ 200 ppm (T9S2) recorded minimum annual shoot extension growth (16.92 cm), internodal length (1.82 cm) and leaf area (22.20 cm2) along with increase in fruit set (18.34%) and minimum fruit drop (32.45%). Increased fruit yield (51.24 kg), yield efficiency (4.08) and following year return bloom (24.04%) was noticed in T9S2 treatment. Prohexadione calcium sprayed twice @ 200 ppm (T9S2) also increased fruit weight (82.85 g), TSS (13.21%) and total sugars (10.23%) closely followed by the double spray of prohexadione calcium @ 300 ppm sprayed twice which was also effective in enhancing the fruit firmness (6.15 kg/cm2) followed by treatment T12S2 i.e. paclobutrazol @ 200 ppm double spray (6.07 kg/cm2). Double spray of prohexadione calcium @ 200 ppm was effective in reducing the vegetative characters and increasing yield and fruit quality characters.