Reducing levels of fruit set is often desirable in many European pear (Pyrus communis L.) cultivars. With a negative linear relationship between crop load and size, management early the season minimises wastage tree carbohydrate resources provides maximum benefits terms size quality. There are several tools available for managing including hand thinning, chemical photosynthetic inhibition throu...

to evaluate growth characteristics and adaptation of new asian pear cultivars (pyrus serotina rehd.) in iran, some growth characteristics and physiological factors of nine asian pear cultivars named ‘ks’6, ‘ks’7, ‘ks’8, ‘ks’9, ‘ks’10, ‘ks’11, ‘ks’12, ‘ks’13, ‘ks’14 and one european, present commercial cultivar ‘shahmiveh’ of iran (control) were evaluated under the climatic conditions of tehran ...

Ultrastructural changes in the cell walls of "Calville de San Sauveur" apples (Malus sylvestris Mill) and "Spadona" pear (Pyrus communis L.) fruit were followed during ripening. In apple, structural alterations in cell walls became apparent at advanced stages of softening and showed predominantly dissolution of the middle lamella. In pears softening was also associated with the dissolution of t...

In contrast to most temperate woody species, apple and pear and some other woody species of the Rosaceae family are insensitive to photoperiod, and no alternative environmental seasonal signal is known to control their dormancy. We studied growth and dormancy induction in micropropagated plants of four apple (Malus pumila Mill.) and one pear (Pyrus communis L.) commercial rootstock cultivars in...

Sand pear (Pyrus pyrifolia) russet pericarp is an important trait affecting both the quality and stress tolerance of fruits. This trait is controlled by a relative complex genetic process, with some fundamental biological questions such as how many and which genes are involved in the process remaining elusive. In this study, we explored differentially expressed genes between the russet- and gre...

A compensatory response, viz. in vivo recovery from radiation damage to mitochondria, occurs in preclimacteric pear fruits (Pyrus communis L.) treated with ionizing radiation. The compensatory response is absent or markedly impaired in senescent fruits irradiated at or near the climacteric peak. Senescent cells failed to recover from harmful effects of radiation on: 1) mitochondrial yield, 2) i...

Mitochondrial fractions isolated from pears (Pyrus communis L.) at the climacteric minimum and peak were subjected to sucrose density gradient centrifugation. The distribution of protein and specific activities of 3 enzymes from this mitochondrial fraction were investigated.Cytochrome oxidase specific activity remained associated with the particulate fraction and increased slightly during the p...

Salicylic acid inhibited ethylene formation from ACC in self-buffered (pH 3.8) pear (Pyrus communis) cell suspension cultures with a K(1) (app) of about 10 micromolar after 1 to 3 hours incubation. Inhibition appeared noncompetitive. Among 22 related phenolic compounds tested, only acetylsalicylic acid showed similar levels of inhibition. Inhibition by salicylic acid was inversely dependent on ...