Effect of plant bio-regulators on fruit growth, quality and productivity of pear [Pyrus pyrifolia (Brum.) Nakai] cv Gola under tarai condition

Abstract: Pear (Pyrus spp.) mainly cultivated in the temperate Himalayan region of India, is an important fruit crop. Although, it is a temperate fruit but tarai region of northern India have great potential for growing different low chilling cultivars of this fruit. But the main problem of these low chill cultivars in this area is vigorous growth with shy bearing habit with heavy fruit drop and poor fruit growth resulting very low yield with much inferior fruit quality as compared to fruits produced in temperate region. Plant bio-regulators have the great potential to boost up reproductive growth resulting higher yield with better quality fruits under tarai region. Hence, a field experiment was conducted to study the role of different plant bio-regulators (PBRs) to prevent fruit drop and to improve fruit growth, quality and the productivity of low chill pear cv Gola. Fifteen years old Gola trees were foliar sprayed or soil drenched with different PBRs viz., gibberellin (GA₃), benzyl adenine (BA) and paclobutrazol (PP₃₃₃) at petal fall (PF) stage followed by two and four weeks after PF or at late fall stage. The results indicate that different treatments had significant effect on all the parameters studied. Minimum fruit drop and maximum productivity was depicted in foliar and soil application of PP₃₃₃ followed by foliar spray of GA₃. However, fruit growth (length and width) and volume at maturity and total sugar content was recorded maximum in combined application of GA₃ and BA. Foliar as well as soil application of PP₃₃₃ was also found effective for increasing the sugar content of the fruit while maximum TSS to acid ratio was also recorded in these two treatments. Based on results, it could be said that the foliar as well as the soil application of PP₃₃₃ is highly effective for controlling shy bearing problem with minimal fruit drop and improved fruit quality resulting higher productivity of marketable fruits of better quality.