Combined Spraying of Boron and Zinc During Fruit Set and Premature Stage Improves Yield and Fruit Quality of European Hazelnut cv. Tonda di Giffoni

Abstract

Boron (B) and zinc (Zn) are essential micronutrients of plant nutrition programs in orchards for securing the crop quality and yield. Although orchard supplementation with B and Zn is a common practice to overcome deficiencies or maintain their optimal levels, the efficiency of combined B and Zn spraying in relation to European hazelnut (Corylus avellana L.) phenological stage has not been investigated so far. Leaf and kernel mineral and functional traits were studied in cultivar Tonda di Giffoni after B and Zn spraying in four phenological stages. During the 2016/2017 season, 9-year-old trees were sprayed with B (0, 800, and 1,600 mg L−1) and Zn (0, 400, and 800 mg L−1) under three treatments: B0+Zn0, B800+Zn400, and B1600+Zn800 implemented in three spring application programs scheduled from October to December (P1: four times, P2: early two times, and P3: late two times). B and Zn treatments in P1 and P3 led to higher Zn concentration both in leaves and in kernels compared with non-sprayed trees. Stabilized nut production increased 2.5-fold under B800+Zn400 in all three programs. Kernel/nut ratio improved in both B+Zn treatments in P1 and P3, while the percentage of blank nuts was reduced compared with B0+Zn0. Increased radical scavenging activity in B+Zn-treated kernels and leaves was not attributed to the accumulation of phenolics in P3 compared with B0+Zn0, whereas B and Zn spraying reduced the level of lipid peroxidation in both studied organs. According to the results, combined B and Zn should be sprayed at the end of spring (P3) on hazelnut plantations in temperate areas such as Southern Chile, whereas early applications (P2) showed an irregularity in nut production and functional traits in nuts. Moderate and partialized rates of B and Zn and the time of implementation contribute to improving the quantitative and qualitative features crucial for future sustainable hazelnut production.

Role of boron and its interaction with other elements in plants

“…These results indicate that the interaction of B x Zn increase the quantity and quality of strawberry fruit. On the other hand, as mentioned above, B and Zn are important microelements for normal plant function ( Shrestha et al., 2020 ; Meriño-Gergichevich et al., 2021 ; Verma et al., 2021 ). However, even though their effects have long been investigated in many agronomical and molecular studies, the interaction of B x Zn remains scarce knowledge at genomic and transcriptomic levels.…”

“…In fruit species, B and Zn are important elements for normal fruit growth and development, whose deficiency affects metabolic processes, such as reduced shoot growth, mineral and nutritional alteration, and fruit quality ( Marschner, 2012 ; Özenç and Özenç, 2015 ; Davarpanah et al., 2016 ). Foliar application of B and Zn in different doses in European hazelnut ( Corylus avellana ) show that only Zn significantly increases in kernels, and also leads to rises in Ca and Na concentration in leaves ( Meriño-Gergichevich et al., 2021 ). The authors conclude that the foliar application of B and Zn (at 800 and 400 mg L -1 respectively) are the most efficient doses for boosting the yield of fruits per plant.…”

Hazelnut and Walnut Nutshell Features as Emerging Added-Value Byproducts of the Nut Industry: A Review

“…Therefore, both byproducts exhibit large hardness and toughness [5,6]. In relation to hazelnut shell thickness of around 1.75 mm [9,20], walnut shell thickness ranges between 1.1 to 1.7 mm according to reports by Koyuncu et al [43] (Table 2).…”

“…Chile has become the main producer country from the Southern Hemisphere, with an off-season nut supply of approximately 52,100 t (4.73% of total world production) in the 2021/2022 season [18] and an estimated production of 136,000 t year −1 for 2030 [18,19]. This nutshell has a mass value of over 50% of the total fruit weight (w/w) in stabilized nut [9,20]. It is becoming the main hazelnut byproduct production.…”

Effects of Boron and Zinc Micro-Fertilizer on Growth and Quality of Jujube Trees (Ziziphus jujuba) in the Desert Area

“…Guilherme et al's findings indicated that appropriate levels of boron can regulate plasma membrane H-ATPase activity and enhance nutrient absorption in citrus trees, thereby increasing citrus yields [36]. Meriño-Gergichevich et al stated that boron and zinc supplementation may enhance the uptake of macronutrients, thus leading to enhanced yield [37]. Along with these lines of evidence, numerous studies have demonstrated that applying boron and zinc micro-fertilizers can effectively boost crop yields; however, determining the optimal application dose remains crucial for achieving maximum productivity gains.…”