Effect Of Rootstocks Research Articles

THE ROLE OF GRAFTING IN IMPROVING THE PRODUCTIVITY OF CUCUMBER UNDER SALINE STRESS CONDITIONS

A greenhouse experiment was carried out during 2017 and 2018 summer seasons at Desert Research Center farm, Ras Sudr, South Sinai. The aim of the experiments was to investigate the effect of different rootstocks and citric acid foliar spray on growth, yield and its components and net income as well as net income diffraction percentage and mineral composition of cucumber plant Safi (F1) hybrid. The foliar spray of citric acid was four concentrations (0, 200, 300 and 400 ppm) and the grafting treatments were check nongrafted, Safi (F1) grafted onto Shentoza or on Coplt rootstocks (Cucurbita moschata Duch.). Strip plot design was used where main plots were assigned for foliar spray and sub plots for grafting. Results showed that grafting increased plant growth, yield and its components, marketable yield, net income and net income diffraction percentage. The increasing was differing according to rootstock source. Grafting, also, increased leaf chlorophyll and fruit potassium and calcium content while sodium content was decreased. The highest values of all measured parameters were obtained, in general, with cucumber plants grafted onto Shentoza rootstock. As for citric acid effects, results indicated that its application increased all parameters except sodium content; the highest values were obtained with cucumber plants sprayed with citric acid at rate 400 ppm. As for the combination between grafting technic and citric acid concentration, the best growth and highest yield and its components were obtained with the cucumber plants grafted onto Shentoza rootstock combined with the highest concentration of citric acid. Also, leaf chlorophyll and potassium of fruits recorded the highest increases, whereas fruit calcium and sodium were not significantly affected

The effect of rootstocks on sugars, acids, carotenoids, chlorophylls, and ethylene of Satsuma mandarin (Citrus unshiu)

This study aimed to evaluate the effect of rootstocks on fruit sugars, organic acids, and carotenoids. The contents of sugars and organic acids in fruits were determined by HPLC. Total acidity (TA), total soluble solids (TSS), and pH value of the juice were also evaluated. Total carotenoids and chlorophylls contents were measured using a spectrophotometer. The content of ethylene in fruits was determined by gas chromatography. HPLC analysis of the juice allowed the detection of 3 sugars and 2 acids. Sucrose was the dominant sugar for all rootstocks. Total sugars ranged from 93.54 (mg/mL) (Flying dragon) to 111.54 (mg/mL) (Swingle citrumelo). Total acids changed from 9.50 (mg/mL) (Trifoliate orange) to 11.45(mg/mL) (Flying dragon). The ascorbic acid content varied from 0.20 (mg/mL) (Flying Dragon) to 0.32 (mg/mL) (Sour orange). The pH value ranged from 3.14 (Flying dragon) to 3.50 (Trifoliate orange), TSS content changed from 10.70 (%) (Flying dragon) to 11.10 (%) (Swingle citrumelo), TSS/TA varied from 11.75 (Flying dragon) to 13.45 (Trifoliate orange). The juice content ranged from 52.18 (%) (Flying Dragon) to 55.63 (%) (Sour orange). The amount of fruit production changed from 15 (Kg /tree) (Flying dragon) to 115 (Kg /tree) (Swingle citrumelo). Total carotenoids varied from 0.09 (Swingle citrumelo) to 0.15 (Sour orange and Flying dragon) (mg/gr DW). Among the four rootstocks evaluated, Swingle citrumelo demonstrated the maximum level of sugars and TSS. The study concluded that the rootstocks can affect sugars, acids, and, carotenoids contents of the fruits.

The effect of new rootstocks with hypersensitivity resistance to Plum pox virus ‘Docera 6’ and ‘Dospina 235’ on the growth and yield of young plum trees

The effect of new rootstocks with hypersensitivity resistance to <i>Plum pox virus</i> ‘Docera 6’ and ‘Dospina 235’ on the growth and yield of young plum trees

Effects of different rootstocks on the growth and cadmium-accumulation characteristics of a post-grafting generation of Cyphomandra betacea seedlings

ABSTRACT To study the cadmium (Cd)-accumulation characteristics of the post-grafting generation of Cyphomandra betacea (Cav.) Sendt., the seeds of C. betacea grafted on Solanum nigrum L., tomato, and eggplant rootstocks were collected and planted in Cd-contaminated soil. Compared with seeds of ungrafted seedlings, the S. nigrum rootstock increased the shoot biomass of the post-grafting generation of C. betacea seedlings, while eggplant and tomato rootstocks decreased or had no significant effects. Only the S. nigrum rootstock increased the chlorophyll a content, net photosynthetic rate, and stomatal conductance of the post-grafting generation of C. betacea seedlings, while the other rootstocks decreased or had no significant effects on these photosynthetic parameters. The S. nigrum rootstock enhanced the superoxide dismutase and catalase activities, and soluble protein content, of the post-grafting generation of C. betacea seedlings, while the other rootstocks reduced or had no significant effects on these parameters. The three rootstocks decreased the Cd contents in different organs of the post-grafting generation of C. betacea seedlings, and the order of treatments was ungrafted > tomato rootstock > eggplant rootstock > S. nigrum rootstock. Therefore, S. nigrum was the best rootstock to promote the growth and decrease the Cd contents in post-grafting generation of C. betacea, and this can benefit C. betacea production in Cd-contaminated areas.

Effect of rootstock on yield, grape composition and wine sensory attributes of Shiraz grown in a moderately saline environment

Background and Aims The study compared the viticultural performance and wine sensory attributes of Shiraz grafted on eight rootstocks with a range in vine vigour and grown under drip-irrigation with moderately saline water. Methods and Results The rootstocks were 140 Ruggeri, 1103 Paulsen, 110 Richter, Ramsey, 101-14, M5489, M5512 and M6262. Ramsey and 140 Ruggeri had the highest leaf area index and M6262 the lowest. Ramsey had highest yield, followed by 140 Ruggeri > M5489 = 110 Richter > M5512 > 1103 Paulsen = 101-14 > M6262. Rootstock M6262 had highest wine chloride concentration of 482 and 384 mg/L in 2012 and 2013, respectively, but salty taste and a thickness mouthfeel (viscosity) were significant only in 2012. Wines from the other seven rootstocks had a chloride and sodium concentration under 175 and 40 mg/L, respectively. Colour density was highest in wine from 101-14 in 2012 and from 101-14, 1103 Paulsen and M5489 in 2013. A salt tolerance index (STI) for the eight rootstocks was calculated based on yield, leaf area index, grape juice chloride and sodium concentration and wine colour density. Conclusions Rootstock M6262 had lowest STI in both years. M5489 had highest STI in 2013 followed by 110 Richter = M5512 = 101-14 = 140 Ruggeri. The recognition threshold for salty taste may lie between a chloride concentration in wine of between 384 and 482 mg/L. Significance of the Study The STI, based on five wine grape performance parameters, provides a promising measure of rootstock salt tolerance compared with the traditional parameters of yield and/or capacity for salt exclusion.

The influence of grafting on crops’ photosynthetic performance

In a near scenario of climate change where stress-derived limitations on crops' yield by affecting plant gas-exchange are expected, grafting may become a cheap and easy technique to improve crops photosynthetic performance and water-use efficiency. Inconsistent data of the effect of rootstocks over gas-exchange can be found in literature, being necessary an integrative analysis of the effect of grafting over photosynthetic parameters. With this aim, we present a compilation of the effect of graft on the net CO2 assimilation rate (AN) and other photosynthetic parameters across different species with agronomic interest. No differences were observed in any photosynthetic parameter between non-grafted and self-grafted plants under non-stress conditions. However, differences were found depending on the used rootstock, particularly for the intrinsic water-use efficiency (WUEi). We observed that variations in AN induced by rootstocks were related to changes in both diffusive and biochemical parameters. Under drought or salt stress, different photosynthetic performances were observed depending on the rootstock, although the high variability among studies promted to remarkable results. Overall, we observed that grafting can be a useful technique to improve plant photosynthetic performance, and therefore, crop yield and WUE, and that the rootstock selection for a target environment is determinant for the variations in photosynthesis.

Maturation of early-ripening mandarin as affected by scion and rootstock cultivars in western Santa Catarina, Brazil

ABSTRACT In Santa Catarina, Brazil, ‘Satsuma Okitsu’ and the ‘common mandarin' (Citrus deliciosa Ten.) are the widely known mandarin varieties harvested earlier than 'Ponkan'. This study analyzed and compared the maturation evolution of early maturing mandarins in two rootstocks. The experiment had as treatments combinations of the scion cultivars SCS458 Osvino, Clemenules, Satsuma Okitsu and Mexirica do Rio IAC and the rootstocks ‘Swingle’ and ‘IAC 387 Carrizo’. Fruit were sampled during ripening to evaluate soluble solids (SS), total acidity (TA), ratio (SS/TA), juice content and skin color (CIE Lab parameters and color index - CI). Treatments were compared by analysis of variance and linear and nonlinear modeling. Scions significantly affected the evaluated variables, but no rootstock effect was found. ‘SCS458 Osvino’ showed earlier ratio and, mainly, CI, but its juice content was low in part of the period. ‘Satsuma Okitsu’ and ‘Clemenules’ presented, early, higher CI and ratio ​​than ‘Mexirica do Rio IAC’. In conclusion, the cultivars SCS458 Osvino, Satsuma Okitsu and Clemenules are more precocious in maturation compared to ‘Mexirica do Rio IAC’, and the first is the most precocious in peel maturation.

Effect of different rootstocks on Persian lime (Citrus latifolia T.) postharvest quality

Mexico is the world’s leading Persian lime (Citrus latifolia T.) fruit producer and exporter. The use of rootstocks in citrus may increase fruit quality; however, the most used rootstock in Mexico is Sour orange, which is susceptible to the citrus tristeza virus. The objetive of this work was to evaluate the effect of rootstock (Sour orange, Volkamerian lemon, Flying dragon, Swingle citrumelo and C-35 citrange) on Persian lime fruit quality parameters. Peel thickness, juice content, pH, total titratable acidity (TA), total soluble solids (TSS), weight loss, pectin content, organic acids, sugars and characterization of essential oil components were evaluated. The use of rootstocks had no effect on juice content, pH, TA, organic acids (oxalic, malic and ascorbic) and sugars content (fructose, glucose and sucrose). Fruits from trees grafted on Sour orange and Volkamerian lemon showed the highest pectin yield, while Volkamerian lemon and Flying dragon showed the highest content of citric acid. The aromatic profile of Persian lime essential oil was affected by rootstock type. Fruits from trees grafted on Flying dragon showed a darker and more intense green color, the highest values of TSS and lower percentage of weight loss.

Comprehensive metabolic profiling to decipher the influence of rootstocks on fruit juice metabolome of Kinnow (C. nobilis × C. deliciosa)

The effect of rootstocks on flavor-related compounds, and nutrition and processing quality of Kinnow mandarin (C. nobilis × C. deliciosa) was investigated by targeted metabolomics approach employing LC–MS/MS and GC–MS/MS. Fruit samples were collected from mature trees grafted on six rootstocks, viz. Rough lemon 1 (C. jambhiri Lush), Rough lemon 2 (C. jambhiri), Sour orange (C. aurantium ‘Karun Jamir’), Cleopatra mandarin (C. reshni), Pectinifera (C. × depressa ‘Pectinifera’), and Shekwasha (C. × depressa ‘Shekwasha’). The data revealed significant differences in the concentration of some primary and secondary metabolites. Sour orange rootstock showed a higher concentration of polyphenolics and limonoid aglycones and a lower concentration of sugars, organic acids and aroma volatiles as compared to Shekwasha and Pectinifera. Rough lemon and Cleopatra rootstock presented desired concentration of organic acids and limonoid aglycones with moderate concentration of vitamins (B-complex and C), polyphenolics, and aroma volatiles. Principal component analysis (PCA) segregated Kinnow fruit grafted on different rootstocks into different PCs based on primary and secondary metabolites. Such differences indicate the influence of rootstock on Kinnow metabolome. This study highlights the importance of metabolomics in illuminating metabolic profile of citrus, thereby aiding in the selection of the desired rootstock for intended fruit quality.

The influences of rootstock and pruning seasons on productive and physicochemical traits of ‘Niagara Rosada’ grape

The current study aimed to evaluate the effect of different rootstocks (‘IAC 766’, ‘IAC 572’, ‘IAC 313’, ‘IAC 571-6’ and ‘106-8 Mgt’) on the physicochemical quality of ‘Niagara Rosada’ grape under Brazilian subtropical climate. In this study, a vineyard trellising system supported three years old vines at a density of 6536 plants ha-1. Therefore, evaluations consisted of three pruning seasons: two winter pruning (August 2011 and September 2012) and a summer pruning (January 2012). A complete randomized block design was conducted, subdivided into plots, with five replicates, the plots represented by 5 rootstocks and subplots by pruning seasons. We evaluated bunch number per plant; bunch, berry and rachis fresh mass; berries number per bunch; soluble solid, pH and titratable acidity content in the grape must. Results showed that ‘Niagara Rosada’ grafted onto ‘IAC 572’, presented the highest bunch mass (227g), rachis fresh mass (7.5g) and berries number per bunch (66); while ‘IAC 313’ rootstock performed the lowest values. Moreover, ‘IAC 766’ and ‘106-8 Mgt’ rootstocks presented the highest soluble solid and titratable acidity content, due to these rootstock’s precocity. Furthermore, the highest ratio between soluble solid and titratable acidity was found in ‘Niagara Rosada’ grafted onto ‘IAC 313’ and ‘IAC 571-6’ rootstock.

Effects of different rootstocks on cadmium accumulation characteristics of the post-grafting generations of Galinsoga parviflora

A pot experiment was conducted to study the effects of different rootstocks on the cadmium (Cd) accumulation characteristics of the post-grafting generations of Cd-hyperaccumulator Galinsoga parviflora plants. Five treatments, ungrafted and G. parviflora seedlings grafted on the rootstocks of Kalimeris indica, Senecio scandens, Conyza canadensis, and Artemisia sieversiana, were utilized. The four rootstock grafts decreased the shoot biomass of the G. parviflora post-grafting generation compared with ungrafted. The K. indica and S. scandens grafts increased the Cd concentration in shoots of the G. parviflora post-grafting generation by 15.06% and 14.40%, respectively, compared with ungrafted, while the C. canadensis and A. sieversiana grafts had no significant effects. K. indica grafts increased the amount of Cd extracted by shoots of the G. parviflora post-grafting generation by 10.59% compared with ungrafted, while the other treatments resulted in decreases. Compared with ungrafted, the different rootstocks had no significant effects on the photosynthetic pigment content of the G. parviflora post-grafting generation, and only C. canadensis grafts increased the superoxide dismutase activity level, while only K. indica grafts increased the peroxidase activity level. Therefore, the K. indica rootstock could increase the phytoremediation capability of G. parviflora post-grafted plants grown in Cd-contaminated soil.

Effect of Rootstock and Arginine Spraying in Some Vegetative Growth Characteristics for Two Citrus Species

The study was carried out to study the effect of arginine spraying and rootstocks difference in some shoot growth to four cultivars. A Randomized Complete Block design (RCBD) in a factorial experiment was used with three factors, namely: Arginine levels (0 and 250 mgL-1), Citrus rootstocks (Sour orange, Volkameriana lemon and Troyer citrange) and Citrus species (Navel orange, local orange, common mandarin and Clementine mandarin) in three replications. Results analyzed according to SAS and differences between the means compared using Duncan's test at 0.05 probability level. Results showed navel orange was superior in stem diameter and carbohydrate, Clementine mandarin superior in plant length, Troyer strange superior in plant length, arginine superior in plant length, stem diameter, leaf area, carbohydrate and N. Interaction between Clementine mandarin and volkameriana superior plant length and interaction with troyer citrange superior in leaf area, and interaction with sour superior in leaves content of N, navel orange interaction with troyer citrange in stem diameter and carbohydrate. Interaction clementine mandarin with Arginine superior in plant length, interaction arginine with common mandarin in N content, interaction arginine with orange navel superior in stem diameter and carbohydrate, and interaction troyer citrange rootstock with arginine superior plant length and leaf area,Triple interaction between clementine mandarin with volkameriana rootstock and arginine superior in plant length, interaction common mandarin with sour and arginine superior in N content, and superior navel orange with troyer citrange rootstock and arginine in stem diameter and carbohydrate content, and local orange with sour rootstock and arginine superior in leaf area.

Effect of Rootstock and Arginine Spraying in Some Chemical Growth Characteristics for Two Citrus Species

The study was carried out to study the effect of arginine spraying and rootstocks difference on some shoot growth for four citrus cultivars. A Randomized Complete Block design (RCBD) in a factorial experiment was used with three factors, namely: Arginine levels (0 and 250 mg L-1), Citrus rootstocks (Sour orange, Volkameriana lemon and Troyer citrange), and Citrus species (Navel orange, local orange, common mandarin and Clementine mandarin) in three replications. Results were analyzed according to SAS and differences between the means compared using Duncan's test at 0.05 probability level. Results showed that navel orange was superior in total leaves chlorophyll content and arginine. Navel orange grafted on Volkameriana lemon rootstock was superior in leaves content of P, K and arginine. Spraying with arginine was superior in leaves content of arginine, while triple interference was superior in leaves content of P, arginine and K, while Volkameriana lemon rootstock was superior in leaves content of p and total chlorophyll. Spraying with arginine increased leaves content of P, k and total chlorophyll. Common orange grafted on Troyer Citrange was the superior in leaves content of total chlorophyll after spraying with arginine and at triple interaction. Common mandarin grafted on Volkameriana lemon rootstock gave the highest content of P. Volkameriana lemon rootstock treated with arginine was superior in leaves content of P and Arginine.

Rootstock effect on physico-chemical properties and content of bioactive compounds of four cultivars Cornelian cherry fruits

There is a growing interest in the fruits called 'superfoods' (functional foods). These fruits are characterized by a high content of bioactive substances and high taste qualities. Four cultivars of Cornelian cherry were planted on rootstock or on own-root. The Cornus amomum seedlings used as a rootstock significantly reduced the size of the cornelian cherry trees. The rootstock should not negatively affect the quality of the fruit, and even it would be advisable to increase their consumer value. Had to varying degrees an impact on the content of macro and micronutrients in the leaves and fruit and their mass. The fruit weight was in the range of 156 g (‘Schönbrunner’) – 477 g (‘Jolico’), and firmness 129 Gmm−1 (‘Jolico’), 211 Gmm−1 (‘Shumen’). The fruits were yellow ('Yellow') to dark red ('Jolico'). Cornelian cherry 'Jolico' from rootstock were characterized by higher inhibition of antidiabetic enzymes (α-amylase IC50 4.17, α-glucosidase IC50 13.25) and free-radical scavenging activity (DPPH 40.9 μmol g-1, ABTS+ 48.7 μmol g-1). However, the fruits of ‘Jolico’ from rootstock showed a significantly increased content of anthocyanin (871.46 mg100 g−1). 'Jolico' in rootstock was characterized by a much higher content of polyphenolic compounds (1750.6 mg100 g−1) and total anthocyanin (871.46 mg100 g-1) compared to the other tested Cornelian cherry cultivars. Rootstock did not have an influence on the creation of total flavanols, total polyphenols, and total hydroxycinnamic acid compounds in comparison to own-rot plants.

The rootstock effects on vigor, production and fruit quality in sweet cherry (Prunus avium L.)

The rootstock effects on vigor, production and fruit quality in sweet cherry (Prunus avium L.)

Grape Rootstock Response to Salinity, Water and Combined Salinity and Water Stresses

Diminishing availability of non-saline water in arid and semiarid regions is of concern to all irrigated agricultural producers, including wine and grape producers. Grapes are not a salt tolerant crop and producers often face the choice of either limiting fresh water application, using alternative saline waters or a combination of both. We examined the salt tolerance and effect of restricted water application on three purported salt tolerant rootstocks grafted to Cabernet Sauvignon scion in a 4-year replicated field experiment. ANOVA indicated significant effects of salinity water stress and rootstock on fruit yields. The 140 Ruggeri scion was the top producer across all treatments including control, followed by Salt Creek, with St. George significantly less productive than 140 Ruggeri across all treatments. In terms of salt tolerance, Salt Creek and 140 Ruggeri were not statistically different but St. George was significantly less tolerant than Salt Creek. In terms of drought tolerance (relative yield), there were no statistical differences among rootstocks. Soil salinity profiles and soil moisture sensors indicated reduced water consumption under high salinity, thus no matric stress under 60% of optimal water application when high salt stress was present. The multiplicative stress model where salt and water stress are individually evaluated did not satisfactorily predict yield under combined salinity and reduced water application, likely due to decreased water consumption under saline conditions. Short term (one year) experiments underestimate salt damage to grape vines as salt tolerance decreased over the 4-year experiment.

Effects of rootstocks on storage performance of Nova mandarins

In this research, the effects of rootstocks on the storage performance of Nova mandarins grafted on Carrizo citrange, Troyer citrange, or sour orange grown in the ecological conditions of Dortyol were studied. Fruits were harvested at optimum maturity and kept at 4 °C and 6 °C for 120 days. Changes in weight loss, incidence of fungal decay and physiological disorders, juice content, total soluble solids (TSS), percent fruit with green button, titratable acidity (TA), juice pH, vitamin C content, and rind color (L*, C*, h°) were monitored at 15-day intervals during storage to determine the effects of rootstock on postharvest quality of Nova mandarins. The fruit of Nova mandarin grafted on sour orange and Carrizo citrange had higher weight loss than Troyer citrange. Weight loss from Nova mandarins kept at 4 °C and 6 °C reached 7.71% and 12.21%, respectively, after 120 days of storage. Juice pH, incidence of fungal decay, and physiological disorders increased, while juice content, TA, vitamin C content, percent fruit with green button, and L*, C*, and h° values of rind color decreased in the Nova mandarin cultivar during cold storage. According to the data, the fruits of Nova mandarin grafted on Carrizo citrange, Troyer citrange, or sour orange were stored better at 4 °C than 6 °C. Fruit could be kept at 4 °C for 75 days and at 6 °C for 45 days without any quality deterioration.

Effects of different rootstocks on cadmium accumulation of grafted Cyphomandra betacea seedlings

ABSTRACT To study whether grafting can reduce the heavy metal uptake of Cyphomandra betacea, C. betacea seedlings were grafted onto three different rootstocks (eggplant, Solanum nigrum, and tomato) and planted in cadmium (Cd)contaminated soil. Compared with ungrafted seedlings, S. nigrum rootstock increased the biomass of different organs of C. betacea seedlings, while eggplant and tomato rootstocks decreased it or had no significant effect. Chlorophyll a, chlorophyll b, and total chlorophyll contents of C. betacea seedlings were ranked as follows: S. nigrum rootstock > ungrafted > eggplant rootstock > tomato rootstock. The three rootstocks had no significant effects on the superoxide dismutase activity of C. betacea seedlings. Solanum nigrum rootstock enhanced the peroxidase and catalase activities and soluble protein content of C. betacea seedlings, while the other rootstocks reduced or had no significant influence on these parameters. The three rootstocks increased the Cd content of aboveground organs of C. betacea seedlings as follows: S. nigrum rootstock > eggplant rootstock > tomato rootstock > ungrafted. Grafting onto S. nigrum rootstock can therefore promote the growth of C. betacea; however, all rootstocks investigated in this study promote Cd uptake in C. betacea and thus cannot be used in Cd-contaminated areas.

Effects of bottle gourd (Lagenaria siceraria) rootstocks on plant nutrient content of watermelon [Citrullus lanatus (Thunb.) Mats. &amp; Nak.] leaf and nitrogen use efficiency

In this study, rootstock effects of bottle gourds on nutrient uptake and nitrogen use efficiency of watermelon were investigated. Watermelon seedlings were grafted onto Birecik, Skopje, Emphasis, 216 and FRGold. Non-grafted plants were used as control. The seedlings were transplanted and kept under plastic tunnel until climatic conditions were suitable for watermelon cultivation. Experimental area was amended with doses of 18 kg N da-1, 20 kg P2O5 da-1 and 18 kg K2O da-1based on soil analysis. No micro-nutrient fertilizer was applied. While total P and 1/3 of N and K were applied as base fertilizer before transplanting, the second and third portions of the N and K were applied 20 and 40 days after transplanting, respectively. The experiment planned as a completely randomized block design and repeated four times, each replication has 15 plants. The seedlings were transplanted with 200 x 50 cm spacing. Macro and micro-nutrient contents were analyzed in fully grown seventh and eighth leaves from soot tips. While N, P, K and Ca contents of the leaves did not show significant differences between graft combinations and control plants, Mg concentration was significantly affected by rootstocks. All graft combinations had higher Fe concentration in the leaf than non-grafted plants. Cu and Zn concentrations showed significant variation based on rootstock. Higher nitrogen use efficiency (ton yield kg N-1) was recorded in all graft combinations as compared to controls. Bottle gourd rootstocks used in this study enhanced the nutrient uptake, plant growth and total fruit yield.

Effect of rootstock and nitrogen fertilizer on growth and yield in watermelon

ABSTRACTHerbaceous grafting can be used to manage numerous soilborne pathogens in cucurbits. Rootstocks have been reported to increase the growth of the scion possibly due to more efficient use of nitrogen compared with non-grafted plants. The first objective of this study was to determine if the commercial rootstocks ‘Strongtosa’, ‘Carnivor’, or ‘Macis’ improve growth and production of the watermelon ‘Melody’ scion. The second objective was to determine whether these rootstocks have different nitrogen requirements in open-field production compared with non-grafted ‘Melody’. Field studies were conducted in 2013 and 2014 on the Sandhills Research Station in Jackson Springs, North Carolina. Nitrogen fertiliser was applied via drip irrigation at 0, 84, 126, 168, and 252 kg⋅ha−1. A linear relationship between nitrogen rate and rootstock cultivar existed; however, in all cases the non-grafted plants produced more than all grafted plants. Average fruit weight from the non-grafted plants was also higher than the grafted plants. Fruit from ‘Carnivor’- and ‘Strongtosa’-grafted plants had higher flesh firmness compared with non-grafted ‘Melody’. Our findings suggest that rootstocks do not increase yield or growth in the scion nor do they require different nitrogen application rates. However, some rootstocks do improve overall fruit quality.