IMPACT OF BORIC ACID SPRAYING DATE WITH DIFFERENT CONCENTRATIONS ON YIELD AND FRUIT QUALITY OF Pyrus communis cv. 'LE-CONTE' PEAR TREES

Abstract

The aim of the study was to examine the response of pear (Pyrus communis, L.) trees to foliar applications of boric acid. The experiment was carried out during 2010-2011 and 2011-2012 seasons in a commercial orchard in El-Khatatba city, Monifia Governorate, Egypt on mature 'Le-Conte' pear trees grafted on Pyrus communis seedlings planted at a space of 5×5 m on a sandy soil under drip irrigation system and modified central leader trained. Annually, foliar sprays with boric acid were applied (i) at 1 st September after harvest or (ii) at white bud stage before bloom. Spray treatments involved application of boric acid at a rate of 50, 100 or 150 ppm. Trees untreated with boric acid served as the control. The results revealed that foliar applications of boric acid after harvest or before full bloom at white bud stage increased boron concentration in flowers, fruit set percentage and fruit yield. Additionally, these applications resulted in higher mean fruit weight, size, length, diameter, firmness, seed number per fruit, soluble solids concentration and titratable acidity than those from the control trees. These findings indicate that pre-bloom and postharvest boric acid sprays are successful in increasing pear tree yielding and in improving fruit set. But, boric acid application at the rate of 150 ppm at 1 st September after harvest was superior in this respect.

Success Rate of Individual Pollinizers for the Pear Cultivars “Ingeborg” and “Celina” in a Nordic Climate

“…Generally, all presented data in this study are in accordance with the studies done by Falk Kühn and Bertelsen [56], who examined the cultivar "Clara Frijs", by Sheiki et al [57], who worked with pear cultivars native to Iran and by Quinet et al [58], who studied the cultivar "Conference", but they are higher than the results of Shalan [59] who studied the commercial pear cultivar "Leconte" in Iran and Tatari et al [60].…”

Effects of foliar application of gibberellic acid, boric acid and sucrose on noni (M. citrifolia L.) fruit growth and quality

“…High growth rate and yield in BA treatments is attributed to a boost in metabolism via uptake of boron. As stated earlier, boron enhances cell division and cell enlargement, together with increasing the rate of sugar transport to actively growing regions and developing fruits (Shalan, 2013;Sharma, 2016). Significant increase in the fruit sizes with foliar spraying of BA were also reported for guava (Pippal et al, 2019), pineapple (Wei et al, 2018) and mandarin (Ullah et al, 2012).…”

Efecto de la aplicación foliar de boro en el desarrollo fenológico y cuajado de fruto de gulupa (<i>Passiflora edulis</i> f. <i>edulis</i> Sims)

“…El incremento en el porcentaje de cuajado de fruto de gulupa, observado en este estudio, indica que la aplicación exógena de B favorece a la fructificación y que bajo deficiencia de B se reduce el número de frutos, lo cual concuerda con datos reportados para P. edulis f. flavicarpa (Freitas et al, 2006;Añez y España, 2011). Resultados similares también han sido reportados para otras especies frutales como Malus domestica (Wojcik et al, 2008), Pyrus communis (Shalan, 2013), Prunus persica (Yadav et al, 2013), Persea americana (Boldingh et al, 2016), entre otras.…”

“…En la presente investigación se observó que el mayor porcentaje de cuajado de frutos se obtuvo con la aplicación de B en etapa de formación de botón floral con los tratamientos T100 y T150 para los dos ciclos productivos. Resultados similares han sido reportados para Pyrus communis (Shalan, 2013), Solanum melongena (El-Gawad y Osman, 2014) y Ribes grossularia (Wójcik y Filipczak, 2015). Los resultados obtenidos para el desarrollo de botón floral y cuajado de fruto fueron similares a otros trabajos; se observó que la aplicación de B sobre los tejidos reproductivos mejora la producción de flores y cuajado del fruto, debido a que estos órganos son altamente demandantes de B por las altas tasa de crecimiento y las paredes celulares ricas en pectina (Marschner, 2012;El-Gawad y Osman, 2014).…”