Effects of Foliar-applied Boron on Fruit Retention, Fruit Quality, and Tissue Boron Concentration of Pecan

Abstract

<jats:p>Previous studies with a variety of tree species have demonstrated enhanced flowering, fruit set, and yield with foliar boron (B) applications. The effects of foliar-applied B on pecan [<jats:italic>Carya illinoinensis</jats:italic> (Wangenh.) K. Koch] in the southeastern United States are poorly understood. This study was undertaken to investigate the effect of foliar B application on leaf tissue B concentration, fruit retention, and kernel quality of pecan. Controlled pollination studies showed no effect of B on fruit retention of ‘Stuart’ pecan. Tissue B concentration, fruit retention, and percent kernel of ‘Desirable’ pecan were occasionally enhanced by both two and five B applications made before and through the pollination window in multiple studies over 3 years. As long as leaf B is within the recommended sufficiency range, timing of foliar B application during the critical prepollination period appears to be more valuable for pecan production than are increasing leaf B levels. Given the production enhancements observed here, and the low cost of B fertilizers, the practice of foliar B application merits consideration as a component of pecan orchard management when tank-mixed with normal prepollination pesticide or nutrient sprays.</jats:p>

Influence of boron in organic red clover (Trifolium pratense L.) seed production

“…These results indicate that the highest increase in seed yield was found when B was applied in low rates. The timing of foliar B application has also been shown to be important in pecan and almond production (Nyomora et al ., ; Wells et al ., ), but has not yet been investigated in red clover seed production. The great variations in seed yield between the fields were probably due to success of pollination, method of harvest (performed by hand in field 2) and crop stand.…”

Boron in forest trees and forest ecosystems

“…Also, pollen fertility can be markedly reduced by B deficiency . In nut and fruit trees, for example pistachio, pecan and olive, fruiting is known to be particularly affected by B deficiency (Perica et al, 2001;Wells et al, 2008). To our knowledge, there are no studies on B deficiency effects on seed set in forest trees, but it is likely that these occur in regions with low B availability.…”

Pecan Nutrient Element Status and Orchard Soil Fertility in the Southeastern Coastal Plain of the United States

“…Foliar B application has been recently shown to increase pecan kernel quality and fruit retention under certain conditions (Wells et al, 2008). Mean leaf B was well within the recommended sufficiency range in 2005 and 2008 (Table 3).…”

“…Since that time, most producers only apply three boron applications per season. Increases in percentage of kernel and fruit retention have been observed with properly timed foliar boron sprays at leaf B concentrations below the current recommended minimum concentration (Wells et al, 2008).…”