Effect of Fruit Thinning on ‘Hosui’ Pear Fruit Quality and Yield

Abstract

In Bhutan, naturally occurring local type of pears were grown. Asian or Nashi pears are recent introduction which have become quite popular in eastern Bhutan since it was promoted by Agriculture Research and Development Centre (ARDC) Wengkhar. Although, horticulture has been gaining momentum in recent years, many growers in Bhutan follow traditional methods of crop cultivation and thus, majority of farmers still do not adopt important aspects of fruit production like fruit thinning. In commercial fruit farms elsewhere, fruit thinning is an essential management practice. However, in Bhutan, it is rarely practiced and there is no empirical study on its benefits. Fruit thinning is believed to be beneficial in increasing yield efficiency whilst also sustaining or increasing market returns by improving the fruit size and quality. Thus, a study was conducted in 2019 and 2020 at ARDC, Wengkhar. Effect of hand thinning on Hosui pear was assessed by randomly sampling 15-year-old Hosui trees with four replications – each tree treated as an experimental unit. Canopy of these trees were divided into two equal halves so that one half represents thinning and the other half non-thinning treatments. The treatments were randomly assigned to the two halves of each tree. Hand thinning resulted in significant increase in the fruit weight by 39%, fruit diameter by 12% and fruit height by 12 % over the non-thinning treatments; Total Soluble Solids (TSS) content, an indicator of taste, was greater by 9%. However, the overall yield was lower in the thinning treatments but in the second year of the study, the mean fruit yield in thinning treatments increased by 55% while the yield of non-thinning treatments plummeted by 33%. Hence, the study indicates that fruit thinning has significant effect on fruit quality and yield stability.