Effect Of Rootstocks Research Articles

Effect of citrus root stocks and melatonin spraying on some biochemical characteristics under salt stress conditions

This research was conducted determine the impact of spraying the increase regulator melatonin on the tolerance of some rootstock to salt stress. The results showed that Sour Orange root was significantly superior to the rest of the rootstocks, and recorded the highest increase in the rate (Height, diameter, quantity, and the area for leaves of plant), while the root Volkamer lemon was significantly the best by recording the highest rate of arid mass of the root system and plant life. Furthermore, irrigation with electrical connection water (1.7 ds.m-1) led to obtaining the highest values for vegetative plant girth growth characteristics (plant girth, stem diameter, number of leaves, leaf area, dry weight of the vegetative and root system and root length). Moreover, treatment with the growth regulator melatonin at a concentration of (100 mg.L-1) showed greatest percentage in the trait (plant height, diameter of the stem, number of leaves, size of the leaves, and dry weight of the vegetative both root system and root length). As well as, the binary and triple interactions between these study factors led to a clear significant superiority in the studied traits compared to the comparison treatment, as the triple interaction treatment (Sour Orange root + melatonin at 100 mg.l-1 as the concentration+ Irrigation of salinity water with concentration 1.7 ds.m-1) was the most significant treatment by giving the highest increase in the rate of vegetative characteristics. Finally, the treatment (rootstocks Volkamer lemon + melatonin at 100 mg.l-1 as the concentration + Irrigation of salinity water with concentration 1.7 dm. m-1) recorded the highest rate of length and weight of the root when it is dry system.

The effect of rootstock in long-term performance of the peach cultivar ‘Redhaven’

The effect of rootstock in long-term performance of the peach cultivar ‘Redhaven’

Large-scale and accurate non-destructive visual to near infrared spectroscopy-based assessment of the effect of rootstock on peach fruit internal quality

Development of reliable non-destructive tools to assess internal quality of fleshy fruits has been insufficient due to poor calibration approaches. A novel rootstock × fruit developmental stage calibration approach allowed the development of accurate multivariate prediction models, using visible to near infrared spectroscopy (Vis-NIRS), for the rapid assessment of peach internal quality and maturity in the field. Rootstocks control tree size, which dictates the canopy’s micro-environment the fruit is developing in. Thus, variable genotypes evaluated in this study provided a peach fruit population of diverse physicochemical properties for successful Vis-NIRS-based model calibration. Regression statistics of the created prediction models confirmed this calibration approach and showed that dry matter content (DMC, R2=0.95, RMSEP=0.26%), soluble solids concentration (SSC, R2=0.94, RMSEP=0.36%) and index of absorbance difference (IAD, R2=0.99, RMSEP=0.06) could be predicted accurately with a single scan using a handheld Vis-NIRS sensor. These models could be used to efficiently evaluate the impact of preharvest factors such as newly commercialized Prunus spp. rootstocks on internal quality and maturity during peach fruit growth and development. A ‘proof-of-concept’ field study of the developed technology across two growing seasons showed that rootstocks with increased tree vigor increased yields, but reduced peach internal quality (DMC, SSC) when compared fruit of equal maturity. The technology developed herein could be used to improve preharvest and postharvest management decision making and throughout the supply chain to ensure high fruit quality and increase consumer satisfaction.

Morphological and Physiological Responses of Grafted Melon Subjected to Fusarium Wilt and Water Stress

This study aimed to determine the effects of different rootstocks on crop water stress index (CWSI), some morphological and physiological parameters of grafted melon under soil-borne pathogen (Fusarium oxysporum f.sp.melonis) and water stress conditions. The study was carried out in Çumra District of Konya Province in Türkiye for two years. The main plots consisted of three different irrigation levels and the sub plots consisted of subjects with melon plants with different rootstocks. The experiment was carried out in a split-plot design with three replications. In the study, four different rootstocks; 1-Ungrafted, 2-Ferro, 3-Maximus and TZ 148 were used. Edalı F1 variety (Cucumis melo var. Edalı F1) was used as a scion in the experiment. Irrigation was done in the four vegetation periods (early vegetative, late vegetative, flowering-fruit setting and ripening) of plant. Irrigation consisted of issues to increase soil depth from 0-90 cm to field capacity (I100), 50% (I50) of soil available water field capacity and rainfed (I0). As a result of the experiment, while leaf water potential (LWP) and leaf relative water content (RWC) increased with the increase of irrigation water in both years, the chlorophyll content was higher in I100, stomatal conductance was the highest in I50 of irrigation water, while the increase in irrigation water decreased stomatal conductance. In terms of physiological parameters measured in the plant, chlorophyll content and RWC values in the first year, Ferro, TZ-148 and Maximus rootstock, respectively, in the second year, Maximus rootstock reached the best value stem diameter in both years. CWSI was also affected by the applications.

Field performance of ‘Valencia’ orange trees on diploid and tetraploid rootstocks in different huanglongbing-endemic growing environments

Huanglongbing (HLB, a.k.a. citrus greening disease) has reduced Florida citrus production and acreage substantially since its discovery in 2005. Most commercially important citrus scion cultivars such as sweet oranges are susceptible to the disease and no cure is available at present. This has increased the demand for HLB-tolerant rootstocks to retain tree health and maximize productivity through higher-density plantings. Polyploidy in citrus has been associated with reduced tree size and enhanced biotic and abiotic stress tolerance. This study compared the potential of tetraploid rootstocks with diploid rootstocks for inducing dwarfing of the grafted ‘Valencia’ orange scion and for enhancing productivity and tolerance to HLB. Two trials, one at a poorly drained site in south-east Florida and another at a well-drained sandy site in central Florida, were established in 2015. Tree size, yield, yield efficiency, fruit quality, leaf nutrients, and canopy health were assessed over three production seasons from 2018/19 to 2020/21. The different rootstocks varied significantly in their effects on tree size, yield, and yield efficiency. Tree size induced by the diploid rootstocks, which included the Florida industry standards Swingle, sour orange, X-639, and US-897, was 55% larger on average compared to the tetraploid rootstocks. Cumulative yields were 32% higher on diploid rootstocks compared to tetraploid ones. However, tetraploid rootstocks induced a 27% higher yield efficiency on average. A significant rootstock effect on canopy health and nutrient status was found, but this effect was not consistent across locations and production years. Tetraploid rootstocks did not display higher HLB tolerance than diploid rootstocks, including the industry standards. However, effective tree size control, high yield efficiency, and higher fruit quality induced by many of the tetraploid rootstocks revealed their potential to be used in high-density plantings.

Postharvest quality of apples from ‘Maxi Gala’ trees grafted on different rootstocks

This study analyzed the effect of rootstocks G.213, M.9 and Marubakaido with M.9 interstem of 30 and 20 cm (MB/M.9-30cm and MB/M.9-20cm) on postharvest quality, mineral composition and functional properties of 'Maxi Gala' apples. The evaluations was performed using fruits from a commercial orchard located in Vacaria, RS, Brazil. Fruits were stored for 135 and 147 days in the 2014/2015 and 2015/2016 seasons, respectively, and analyzed one day after harvest and after cold storage (1.0±0.2 °C) followed by seven days in ambient condition. The mineral composition of fruits showed small and inconsistent differences between rootstocks. The MB/M.9-20cm provided higher total antioxidant activity and levels of total phenolic compounds in fruit peel than MB/M.9-30cm. For 2014/2015 season, soluble solids content at harvest was higher in fruits from trees with G.213 rootstock, not differing only from MB/M.9-30cm. In 2015/2016 season, G.213 and M.9 provided higher soluble solids content after storage compared to MB/M.9-30 cm and MB/M.9-20cm. G.213 rootstock anticipated fruit maturity compared to M.9 in 2014/2015 season. Other quality attributes of ‘Maxi Gala’ apples, at harvest and after cold storage, were similar between rootstocks G.213, M.9 and Maruba with M.9 interstem of 30 and 20cm.

Rootstock effects on bitter pit incidence in 'Honeycrisp' apples are associated with changes in fruit's cell wall chemical properties.

Bitter pit (BP) is a physiological disorder of apples that often appears during or after cold storage. Despite being defined as a calcium deficiency disorder, BP is a complex process that is not only affected by the total Ca2+ content in the fruit but also by the proper cellular Ca2+ homeostasis and partitioning. Early investigations have also suggested that rootstocks could affect BP development and severity. In the present study, rootstock effects on BP development were assessed on ‘Honeycrisp’ trees that were grafted on 14 different rootstocks (B.10, G.11, G.202, G.214, G.30, G.41, G.935, G.969, M.26 EMLA, M.9, V.1, V.5, V.6, and V.7). We evaluated BP incidence at harvest, and three months after cold storage for four, and three growing seasons, respectively. BP incidence was significantly reduced in ‘Honeycrisp’ trees on B.10 compared to other rootstocks, whereas trees on V.6 showed the highest percentage of BP at harvest and after cold storage. ‘Honeycrisp’ apples were collected from three different rootstocks (B.10, G.41, and V.6) two months after cold storage and evaluated for mineral nutrient composition, Ca2+ homeostasis, and cell wall properties, e.g., pectin content, pectin de-esterification rate and pectin methylesterase (PME) activity. Water-soluble and insoluble pectin content was markedly higher in fruits from B.10 than in G.41 and V.6. We also observed increased PME enzyme activity and a greater degree of water-insoluble pectin de-esterification in ‘Honeycrisp’ apples from V.6 compared to those from B.10. A significantly higher Ca2+ was found in the fruits from B.10 than G.41 and V.6. Higher Ca2+ and lower Mg2+ levels were also observed in the cell wall and water-insoluble pectin fractions of the fruits from B.10 compared to G.41 and V.6. However, the ratio of cell wall-bound Ca2+ to total Ca2+ was lower in B.10 compared to G.41 and V.6. Together, our results indicate that the tolerance of B.10 to BP could be attributed to a reduced PME activity and lower pectin de-esterification level, which in turn reduced the amount of Ca2+ cross-linked with pectin, and probably increased the apoplastic free calcium concentrations that is essential for maintaining cell membrane integrity and reducing BP development.

Tools for climate resilience in tree fruit I: large-dwarfing rootstocks can alleviate sunburn damage in “Buckeye Gala” apple

Suitable rootstock enhances apple tree resilience. In 2021, we studied “Buckeye Gala” apple ( Malus domestica var. Buckeye Gala") on nine rootstocks with contrasting vigor in NS and BC, Canada. Rootstock effects on vigor, yield, and midday stem water potential were significant in BC. After sustained heat events, the large-dwarfing rootstocks Geneva 935, Geneva 4814, and Geneva 969 had lower ratio of sunburn fruits, resulting in higher projected damage-free yield. We discussed how higher stem water potential and larger canopy volume supported by vigorous rootstocks contributed to alleviate heat stress and improve apple resilience to global warming.

Early detection of graft-incompatibility in hawthorn (Crataegus azarolus L.) trees on apple, pear, and quince rootstocks

Aim of study: This study was conducted to determine the usability of some clonal rootstocks of apple (MM 106 and MM 111), pear (Fox 11), and quince (Quince A) for hawthorn trees propagation. Area of study: Fruit Research Institute, Isparta and Hatay Mustafa Kemal University, Hatay, Türkiye. Material and methods: ‘Sultan’ hawthorn cultivar was budded on the following clonal rootstocks: pear Fox 11, quince A, and apple MM 106 and MM 111. Plants of hawthorn seedlings (Crataegus azarolus L.) budded with ‘Sultan’ cv. were used as control. External visual diagnosis of the scion-rootstock graft combinations was performed by observing visual symptoms in budded trees growing in nursery conditions, as well as anatomic and histological investigations of the incompatibility in the laboratory. Main results: In this study, healthy scion development and callus tissue in the graft region were formed in the seedling rootstock as well as on Fox11 and Quince A clonal rootstocks. In contrast, MM 106 and MM 111 apple rootstocks showed incompatibility symptoms, with insufficient scion vigor and unstructured callus tissue development. Research highlights: ‘Tanslocated’ and ‘located’ graft incompatibility symptoms were observed in Sultan/MM 106 and Sultan/MM 111 combinations. Further studies are necessary to confirm the early good compatibility found in nursery conditions, testing the effect of those clonal rootstocks from different species (Fox11 and Quince A) on vigor, yield, and fruit quality traits in orchard conditions.

Effect of Rootstock on ‘Tasti-Lee’ Tomato Yield and Fruit Quality in a High Tunnel Production System

Grafting tomatoes with vigorous rootstocks can be used to increase yield in high tunnels without significant soilborne disease pressure. However, evidence suggests that grafting with high-yielding rootstocks could compromise the accumulation of primary and secondary metabolites. ‘Tasti Lee’ is a hybrid tomato that is bred to have a superior fresh-eating quality and higher lycopene content. The objective of this experiment was to investigate the yield and fruit quality impacts of grafting ‘Tasti Lee’ with rootstocks with ranging vigor and typical yield performance in high tunnels. Nongrafted ‘Tasti-Lee’ and ‘Tasti-Lee’ scion grafted onto ‘Maxifort’, ‘DRO141TX’, ‘Fortamino’, ‘Estamino’, and ‘RST-04-106-T’ rootstocks were trialed in a high tunnel in Kansas for three consecutive growing seasons (2018–20). The trials were arranged in a randomized complete block design with four replications. Total yield, marketable yield, average fruit size, and distribution of fruit size classes were assessed. Red ripe tomato fruit were harvested to determine the soluble solids content, titratable acidity, lycopene content, vitamin C content, antioxidant capacity, and fruit firmness. ‘Maxifort’, ‘DRO141TX’, ‘Estamino’, and ‘Fortamino’ significantly increased marketable yield (kg/plant) by 31.5% to 47.0% more than nongrafted plants. In contrast, ‘RST-04-106-T’ did not lend any significant yield benefit. Regardless of the rootstock, grafting increased the marketable average fruit weight by 20 g. Grafting did not have significant effects on any of the fruit quality attributes assessed. However, the soluble solids content of fruit from plants grafted to ‘RST-04-106-T’ was 10% higher (P < 0.05) than that grafted to ‘Maxifort’, indicating that rootstock genotype can influence this quality trait. Our findings suggest that growers can graft the tomato ‘Tasti-Lee’ with select vigorous rootstocks to increase marketable yield without sacrificing fruit quality for high tunnel production.

Scions impact biomass allocation and root enzymatic activity of rootstocks in grafted melon and watermelon plants.

Vegetable grafting is increasingly recognized as an effective and sustainable plant production alternative. Grafted plants usually show increased uptake of water and minerals compared with self-rooted plants, mostly thought a consequence of the vigorous rootstocks selected. However, while studies frequently addressed the effects of rootstocks on the performance of scions, knowledge on the influences of scions on biomass allocation, morphology, and metabolic activity of roots is rare. In particular, the plasticity of root traits affecting resource acquisition and its efficiency remains poorly understood. Two different rootstock species, Cucurbita maxima × Cucurbita moschata and Lagenaria siceraria, were grafted in combination with melon (Cucumis melo) and watermelon (Citrullus lanatus). Self-grafted rootstocks were used as control. Plant biomass and root traits were determined after destructive harvesting 30 and/or 60 days after grafting. Traits included biomass allocation, leaf and root morphology, potential activities of four extracellular enzymes on root tips and basal root segments, and root respiration. Successfully grafted scions increase the ratio of root to whole plant dry matter (RMF), and increased ratios of root length to whole plant dry matter (RLR) and to plant leaf area (RL : LA). In contrast, morphological root traits such as diameter, tissue density, and specific root length remain surprisingly stable, and thus scion-induced changes of those traits may only play a minor role for the beneficial effects of grafting in Cucurbitaceae. Incompatibility in melon/L. siceraria grafts, however, was likely responsible for the reduced root growth in combination with clear changes in root morphological traits. Reduced root respiration rates seem to be the effects of a non-compatible rootstock–scion combination rather than an active, C-efficiency increasing acclimation. In contrast, heterografts with melon and watermelon frequently resulted in root-stock-specific, often enhanced potential enzymatic activities of acid phosphatase, β-glucosidase, leucine-amino-peptidase, and N-acetyl-glucosaminidase both at root tips and basal parts of lateral roots—presenting a potential and complementary mechanism of grafted plants to enhance nutrient foraging. The studied melon and watermelon scions may thus increase the nutrient foraging capacity of grafted plants by fostering the relative allocation of C to the root system, and enhancing the extracellular enzymatic activities governed by roots or their rhizobiome.

Performance of parthenocarpic and non-parthenocarpic grafts of cucumber

Effect of rootstock on yield and quality of cucumber scion was studied at Department of Vegetable Science, College of Agriculture, Vellayani, Thiruvananthapuram, Kerala during February-May, 2021. Parthenocarpic and non-parthenocarpic cucumber scions were grafted onto five different cultivated cucurbit species i.e. pumpkin, bottle gourd, oriental pickling melon, culinary melon and ash gourd. Significant variations were observed for all the traits under this study. The highest vine length (4.37 m) was observed in Heera scion grafted onto Lagenaria siceraria rootstock followed by Heera scion grafted onto Cucurbita moschata rootstock (4.13 m). The diameter of rootstock hypocotyl was higher in case of KPCH-1 grafted onto bottle gourd (1.48 mm) and Heera grafted onto bottle gourd (1.43 mm). KPCH-1 grafted on bottle gourd (29.33 days) and culinary melon (31 days) rootstocks showed early female flower initiation. The greater number of fruits was observed in graft combination of KPCH- 1 and bottle gourd (32) followed by parthenocarpic grafts with pumpkin (30.33) and ash gourd (30.33) rootstocks. A greater fruit weight was observed in graft combination of Heera and bottle gourd (7.51 kg) followed by Heera grafted onto pumpkin (7.38 kg). Results of this experiment suggest that these graft combinations can be employed in sustainable vegetable cultivation.

Effects of different rootstock grafting on yield and quality of cucumber

In this study, ‘Xinli No. 3’, ‘Shengli rootstock’, ‘Shenli rootstock’ and ‘Shengzhen No. 1’ were used as rootstock, and ‘Jinchun No. 39’ cucumber was used as scion to study the effects of different rootstock on the yield and quality of grafted cucumber, and to select high quality rootstock suitable for cucumber grafting. Different rootstock affected the survival rate, phenology, the height of plant, stem diameter, growth potential, yield and quality of cucumber grafting. Among them, the survival rate of ‘Shenli rootstock’ grafted cucumber is the highest, and the growth of ‘Shengzhen No. 1’ grafted cucumber is relatively the strongest. There was no significant difference in fruit tuber, melon edge, thorn color and pulp crispness between self-rooted seedling (CK) and each rootstock grafting combination. The average yield of ‘Xinli No. 3’ grafted cucumber plot was not significantly different from that of self-rooted seedlings (CK). The length of ‘Shenli rootstock’ and ‘Shengli rootstock’ grafted cucumber was significantly higher than that of self-rooted seedlings (CK), and the length of ‘Shengzhen No. 1’ Grafted Cucumber was significantly higher than that of self-rooted seedlings (CK). The contents of vitamin C and soluble protein of ‘Shengli rootstock’, ‘Shenli rootstock’ and ‘Shengzhen No. 1’ grafted cucumber were significantly higher than those of self-rooted seedlings (CK), and the contents of soluble sugar were lower than those of self-rooted seedlings (CK). Therefore, ‘Shengzhen No. 1’ and ‘Jinchun No. 39’ have strong compatibility with cucumber. As rootstocks, the grafted cucumber plants not only have strong growth potential and high yield, but also significantly increase the content of soluble protein and vitamin C.

Instrumental and sensory analyses of fruit quality attributes of grafted grape tomatoes in high tunnel organic production systems.

'Vegetative' and 'generative' tomato rootstock types have been proposed based on their different effects on tomato scion growth performance; however, their impacts on fruit quality have not been characterized. No study has been conducted in which the effects of rootstock on grape tomato quality attributes were assessed using sensory and instrumental methods of evaluation. Here, we conducted two experiments to examine the influence of 'DR0141TX', 'Estamino', and 'Multifort' rootstocks (vegetative, generative, and uncharacterized, respectively) on fruit quality properties of determinate and indeterminate grape tomato scions under organic production in high tunnels, including color, size, firmness, dry matter content, soluble solids content (SSC), titratable acidity (TA), pH, and consumer sensory attributes. In both experiments, grafting 'Sweet Hearts' indeterminate grape tomato onto 'DR0141TX', 'Estamino', or 'Multifort' increased fruit size and led to negligible effects on sensory attributes and instrumental measurements of fruit quality attributes. For 'BHN 1022' determinate grape tomato, rootstocks did not exhibit any major impact on fruit quality attributes in Experiment 1. However, fruit quality was compromised by grafting per se and rootstocks, especially 'Multifort', in Experiment 2, as reflected by reduced SSC, TA, and SSC/TA and lower scores for overall appearance, overall acceptability, tomato flavor, overall texture, and sweetness. In general, 'vegetative' and 'generative' rootstocks showed comparable effects on sensory evaluations and instrumental measurements of grape tomato quality attributes for both indeterminate and determinate scions. More research is needed to better characterize rootstock effects on fruit quality, including the flavor-related compounds under different growing conditions. © 2022 Society of Chemical Industry.

Effects of a Local Tomato Rootstock on the Agronomic, Functional and Sensory Quality of the Fruit of a Recovered Local Tomato (Solanum lycopersicum L.) Named “Tomate Limachino Antiguo”

The Old Limachino Tomato is a valuable fruit with exceptional nutritional values and organoleptic sensory properties. However, it suffers from a short shelf-life, compromising post-harvest behavior. As an attempt to improve the fruit’s qualities, Limachino (L) scion was grafted onto rootstock from the rustic landrace Poncho Negro (R). Fruits produced in this graft combination were compared with fruits produced by self-grafted plants (L/L) and from a long-shelf-life cultivar Seminis (LSL). The trials were carried out for 146 days during summer of two consecutive years. Poncho Negro rootstock increased the total number of fruits produced by Limachino scion (L/R). It did not affect the fresh weight of individual fruits but reduced their water content. It has no impact on the Limachino fruit form (quality), a typical characteristic well appreciated by consumers. Fruits produced by LSL exhibited a higher firmness but a lower titratable acidity and antioxidant capacity than L/R and L/L fruits. Panels of 104 untrained final consumers and a trained panel of 13 experts attributed the highest value to L/R fruits and the lowest one to LSL. It was concluded that Poncho Negro rootstock contributes to increasing preferences and the level of acceptability towards Limachino fruits. Further research is needed to develop local technologies in order to expand the production of local tomatoes that are highly valued by consumers.

The Expression of Aroma Components and Related Genes in Merlot and Marselan Scion-Rootstock Grape and Wine.

Rootstocks were bred and selected from several species in order to enhance the resistance against biotic or abiotic stresses. There are few studies on the effect of rootstocks on aroma and related gene expression. This study focused on the effects of three rootstocks, Kober 5BB (5BB), 1103 Paulsen (1103P), and Selection Oppenheim (SO4), on the aroma and volatile-related gene expression levels of Merlot and Marselan berries and wines. These three rootstocks reduced the total aroma content of Merlot wine. 5BB upregulated VvLoXA and showed increased C6 alcohols. 1103P enhanced the linalool from Merlot berry, with marked upregulation of VvLinNer1. Conversely, rootstocks increased the total aroma content of Marselan berry, verified by the related expression levels of volatile-related genes. For Marselan berry, 5BB and 1103P upregulated five VvGTs and nine genes from the LOX and MEP pathway. 1103P increased the contents of C6 alcohols, C6 aldehydes, and citronellol from Marselan berry. Compared to 5BB and SO4, rootstock 1103P provided berries of better quality and richer aroma volatiles to Merlot and Marselan, while all three of the rootstocks had a significant effect on scion–rootstocks.

Effects of drought-tolerant grapevine rootstocks on the mineral contents and fatty acid compositions of grape seeds

BACKGROUND: As the interest in foods with positive effects on human health has increased in recent decades, the importance of the mineral contents and oil compositions of grape seeds has been better understood. However, research on grape seeds to date has largely focused on effects on health and the usability of grape seeds in the food industry and animal feeds. In agricultural research, grape seeds have generally been evaluated as a source of genes in breeding new varieties and as propagation material. OBJECTIVE: Unlike previous studies, this study not only investigates the effect of variety on the changes of pomological properties, fatty acid compositions, and oil, protein, and mineral contents of grape seeds; it also aims to determine the effects of grape rootstocks and growing seasons on those changes. METHODS: The seeds of five grape varieties (Red Globe, Trakya Ilkeren, Ata Sarisi, Hatun Parmagi, and Horoz Karasi) grafted onto drought-tolerant grape rootstocks (1103P and 110R) were analyzed during the growing seasons of 2017 and 2018. RESULTS: Seed size, moisture and oil contents, major fatty acids (palmitic, oleic, and linoleic), and levels of saturated fatty acids, monounsaturated fatty acids, unsaturated fatty acids, and boron varied by variety, rootstock, and season. However, the effects of growing seasons and varieties on the seeds were not limited to these findings; effects were also seen for seed vitality, protein content, and N, K, Ca, and Fe levels of the seeds, among others. CONCLUSIONS: Genotype was found to be the main factor causing changes in the fatty acid compositions and mineral contents of grape seeds. When the factors that we investigated were ordered based on the changes they caused for seeds in general, the sequence that appeared was genotype > growing season > grape rootstock.

Whole-Canopy Photosynthetic Characterization of Apple Tree and the Effects Induced by Grafting on Rootstocks with Different Vigor

Leaf photosynthesis is pivotal for the synthesis of carbohydrates; however, the growth and development of horticultural crops are more closely related to canopy photosynthetic capacity. Measurements of canopy photosynthesis allow a better evaluation of the fruit tree performance at the canopy scale. Therefore, an open chamber system to determine instantaneous canopy apparent photosynthesis (CAPi) was investigated. CAPi slightly overestimated the biomass accumulation by 5.9%, which revealed that the CAPi method is valuable for quantifying canopy photosynthesis. Further, many woody horticultural plants are usually grafted for propagation, such as apples, whereas the rootstocks always influence the canopy size and photosynthesis. In this study, the effect of dwarfing, semi-dwarfing, and vigorous apple rootstocks on canopy photosynthesis was studied. Compared to vigorous rootstock, dwarfing rootstock significantly reduced the leaf net photosynthetic rate and total leaf area by 20.8% and 53.1%, respectively, and resulted in a 59.7% reduction in CAPi. Throughout the study, CAPi was an effective method that should be considered for canopy photosynthesis measurement of horticultural crops in the future.

The effect of rootstocks on mango tree vigour, scion architecture, yield, percentage of flowering terminals in young unpruned trees

The effect of rootstocks on mango tree vigour, scion architecture, yield, percentage of flowering terminals in young unpruned trees

Physiological behavior and nutritional status of almond scion-rootstock combinations in a high-density planting system under warm Mediterranean conditions

• High-density planting with new almond cultivars and Prunus rootstocks in warm area. • SPAD and Fv/Fm affected by the scion-rootstock combinations and the monitoring year. • Significant differences in mineral status among almond cultivars on Prunus rootstocks. • DOP analysis demonstrated low values on less vigorous rootstock R40 than Garnem. • R40 suitable for high-density with medium canopy and balanced nutritional status. • Guara, Lauranne and Tuono on R40 best choice for physiological and mineral parameters. Nowadays, the new tendency for a high-density plantings system for almond requires smaller and more efficient canopies. In this way, appropriate scion-rootstock combination is an important factor in adapting to local conditions and specific training systems. This investigation was dedicated to identify the most suitable scion-rootstock combination for high-density planting of almond under warm Mediterranean conditions. Four almond cultivars ‘Lauranne’, ‘Tuono’, ‘Guara’ and ‘Belona’ budded on two Prunus rootstocks ‘Garnem’ and ‘Rootpac-40′ (R40) and planted at 2m×4m spacing were followed for five successive years. Measurements focused on physiological parameters and the mineral foliar analysis. As a result, strong variability between the scion-rootstock combinations of almond was observed. For all surveyed parameters, significant effects of rootstock, cultivar, and year and their interactions were recorded. Less tree vigor was induced by ‘R40’ with similar medium tree vigor obtained with ‘Lauranne’, ‘Tuono’, and ‘Belona’ cultivars, whereas ‘Guara’ performed the lowest vigor. A significant yearly difference in vigor level could be related to local conditions and crop yield with negative impact during warm and drought year. For physiological parameters, SPAD and quantum yield Fv/Fm values were significantly affected by the scion-rootstock combinations and the monitoring year. ‘Belona’ and ‘Tuono’ performed high SPAD and Fv/Fm values on ‘Garnem’ and ‘Lauranne’ and ‘Guara’ showed the high SPAD and Fv/Fm values on ‘R40’. Mineral tree status revealed differences in leaf macronutrient and micronutrient content for almond cultivars on Prunus rootstocks. Optimal macro elements contents ​​were detected for ‘Guara’ and ‘Lauranne’ on ‘R40’. However, variable microelements contents were observed within different combinations. DOP analysis demonstrated low values on ‘R40’ with the best-balanced and highest imbalanced nutritional status (average ∑DOP index) performed by ‘Lauranne’/‘R40’ and ‘Belona’/‘R40’, respectively. In conclusion, less vigorous rootstock ‘R40’ seems to perform well in high-density planting almond orchards in a warm area. Their best performances were associated with ‘Guara’, ‘Lauranne’ and ‘Tuono’. These scion-rootstock combinations inducing size-controlling effect could be considered to implement a new high-density planting system for almond in a warm area.