Kale Research Articles

Malatya ili kayısı alanlarında zararlı Sphaerolecanium prunastri (Boyer de Fonscolombe, 1834) (Hemiptera: Coccidae) (Erik koşnili)’nin yayılış alanları, bulaşma oranları ve doğal düşmanlarının belirlenmesi

Kayisi Turkiye icin onemli bir tarimsal urundur. Ozellikle Malatya ili kayisi uretiminin % 60’ini karsilamaktadir (Anonymous, 2008). Malatya hem yetistirilen miktar, hem de kalite itibariyla Turkiye’de kayisiyla on plâna cikan bir sehirdir. Kayisinin yas ve kuru tuketiminin yaninda bircok degisik kullanimi da bulunmaktadir. Kayisi cekirdeklerinin tatli olanlari cerez olarak tuketilmekte, aci olanlari ise kozmetik ve ilâc sanayinde hammadde olarak kullanilmaktadir. Ayrica kayisi cekirdeginin tohum ve kabugundan badem yagi, yemeklik yag, benzaldehit (aroma esansi), furfural, aktif karbon, amigdalin ve hidrosiyanik asit elde edilmektedir. Turkiye icin onemli bir tarimsal urun olan kayisinin problemleri icerisinde bitki koruma problemleri de buyuk onem tasimaktadir. Zararlilarda bu problemler icerisinde onemli yer tutmakta olup Ulusoy et al. (2001), Malatya ili kayisi alanlarinda 41 zararli tur tespit etmisler ve bu zararlilar icerisinde bulunan Sphaerolecanium prunastri (Boyer de Fonscolombe, 1834) (Hemiptera: Coccidae) (Erik kosnili)’nin Malatya ilinde nadir gorulen kayisi zararlilari icerisinde bulundugunu bildirmislerdir

Effects of some processing methods on nitrate and nitrite changes in cruciferous vegetables

Changes in nitrate and nitrite content in selected cruciferous vegetables, resulting from blanching, boiling, freezing, frozen storage and boiling after previous freezing, were analyzed. The highest level of nitrate was detected in curly kale (302.0 mg/kg) and the lowest in green cauliflower (61.0 mg/kg). As for nitrite, the respective levels were found in white cauliflower (3.49 mg/kg) and green cauliflower (1.47 mg/kg). Both blanching and boiling of the cruciferous vegetables caused a considerable decrease in the total nitrate content, but at the same time no explicit changes were noted regarding the level of nitrite. In the vegetables stored frozen for 48 h, previously blanched, either an increase or no change was observed in the nitrate level, with the changes in the nitrite level being irregular. In the vegetables stored frozen for 4 months, previously blanched, generally a decrease was noted in the nitrate, and an increase in the nitrite level compared to the levels in the blanched vegetables. Boiling of the frozen vegetables (stored frozen for 48 h) most frequently caused a considerable reduction of the nitrate level in comparison to the content in the raw frozen vegetables. No changes were observed resulting from the boiling of the vegetables previously stored frozen for 4 months. Simultaneously, no explicit changes were found regarding the nitrite level in the frozen vegetable after boiling.

Characterization and Quantification of Flavonoids and Hydroxycinnamic Acids in Curly Kale (Brassica oleracea L. Convar. acephala Var. sabellica) by HPLC-DAD-ESI-MSn

Kale is a leafy green vegetable belonging to the Brassicaceae family, a group of vegetables including cabbage, broccoli, cauliflower, and Brussels sprouts, with a high content of health-promoting phytochemicals. The flavonoids and hydroxycinammic acids of curly kale ( Brassica oleracea L. ssp. oleracea convar. acephala (DC.) Alef. var. sabellica L.), a variety of kale, were characterized and identified primarily through HPLC-DAD-ESI-MS(n) analysis. Thirty-two phenolic compounds including glycosides of quercetin and kaempferol and derivatives of p-coumaric, ferulic, sinapic, and caffeic acid were tentatively identified, providing a more complete identification of phenolic compounds in curly kale than previously reported. Moreover, three hydroxycinnamic acids and one flavonoid with an unusual high grade of glycosylation, quercetin-3-disinapoyl-triglucoside-7-diglucoside, have been tentatively identified for the first time. The influence of different extraction conditions (extraction method, solvent type, solvent/solid ratio, and duration of extraction) was investigated. The total flavonol and hydroxycinnamic acid contents in curly kale determined as rutin equivalents (RE) were 646 and 204 mg of RE/100 g of fresh weight (fw), respectively. The contents of individual flavonoids ranged from 2 to 159 mg of RE/100 g of fw, with main compounds kaempferol-3-sinapoyl-diglucoside-7-diglucoside (18.7%) and quercetin-3-sinapoyl-diglucoside-7-diglucoside (16.5%). After acidic hydrolysis, two flavonol aglycones were identified in curly kale, quercetin and kaempferol, with total contents of 44 and 58 mg/100 g of fw, respectively.

Comparison of concentrations of mercury in ambient air to its accumulation by leafy vegetables: An important step in terrestrial food chain analysis

A biomonitoring network with leafy vegetables was established near a chlor-alkali plant in order to compare the accumulation of mercury to the atmospheric total gaseous mercury (TGM) concentration. Based on data obtained in the reference area the ‘normal’ mercury concentration in vegetables is between 0.6 and 5.4 μg kg −1 FW. The effect detection limits (EDLs) are between 1.2 and 11.0 μg kg −1 FW and the biological detection limits (BDLs), the lowest [TGM] that can be detected significantly, are between 3 and 4 ng m −3. The accumulation rate is lowest for lettuce and high for curly kale that proved to be an excellent accumulator and as such it is very useful for biomonitoring purposes. A comparison made in the 1980s between biomonitoring results with grass and the mercury concentration in leafy vegetables from private gardens nearby proved to be valid when applied to the current biomonitoring results with vegetables.

Effect of cold storage and harvest date on bioactive compounds in curly kale ( Brassica oleracea L. var. acephala)

In this study, curly kale stored at 1 °C for 3 and 6 weeks was compared with plants remaining in the field regarding several properties related to human health and sensory quality. Cold storage had no effect on the antioxidant capacity (ORAC assay), total phenols (Folin-Ciocalteu assay) or flavonol content, but reduced the content of vitamin C and soluble sugars. The ratio ascorbic:dehydroascorbic acid decreased from about 3 to 0.5 upon storage. The largest changes in the content of bioactive compounds were found in plants that remained in the field for 6 additional weeks, including many frost days. In these plants, the levels of flavonols, total phenols and antioxidant capacity were reduced by 25–35% and the vitamin C content by more than 50%, whereas soluble sugars and dry matter increased by roughly 20% and 30%, respectively. Among all the curly kale samples, the antioxidant capacity was positively correlated with the level of total phenols ( r = 0.73, P < 0.001) and total flavonols ( r = 0.70, P < 0.001). Values obtained with a non-destructive method based on chlorophyll fluorescence (ChlF) were well correlated with the flavonol content in the leaves, with the highest correlation found for quercetin ( r = 0.76, P < 0.001). Using the ChlF method, the kinetics of the flavonol content during the experiment was recorded. The same method also showed gradients of flavonol content within the plant, with the highest values in the upper leaves and in the tip of the leaves. ChlF measurement, therefore, proved to be a quick and cost-effective alternative to chemical analyses of the flavonol content in curly kale.

Dietary Antioxidants and Minerals in Crucifers

Broccoli, Brussels sprouts, cabbage, cauliflower and kale are rich sources of antioxidant phytochemicals and significant amounts of dietary fiber. This study was conducted to estimate the variability of some important antioxidants and minerals between, and within, the crucifer accessions in edible portions of plants. Significant variations for protein, carbohydrate, fiber, β-carotene, ascorbic acid and mineral content were observed between, and within, the crucifers. Total carbohydrate content ranged between 2.54 to 4.03 g/100 g, whereas, protein content ranged from 0.41 to 3.57 g/100 g of fresh weight. Mean fiber content ranged from 0.60 to 3.62 g/100 g. Vitamin C content ranged from 22.16 to 82.14 mg/100 g and β-carotene ranged from 1.56 to 9.09 mg/100 g on fresh weight basis. In general kale, broccoli and Brussels sprouts contained significantly higher amounts of vitamin C and β-carotene as compared to cabbage and cauliflower. The total nitrogen ranged from 1.36 to 4.6% and phosphorous from 0.39 to 0.8...

Expression and activity of sulfate transporters and APS reductase in curly kale in response to sulfate deprivation and re-supply

Both activity and expression of sulfate transporters and APS reductase in plants are modulated by the sulfur status of the plant. To examine the regulatory mechanisms in curly kale (Brassica oleracea L.), the sulfate supply was manipulated by the transfer of seedlings to sulfate-deprived conditions, which resulted in an up to 3-fold increase in the sulfate uptake capacity by the root, accompanied by an induction of transcript abundances of the Group 1 and 4 sulfate transporters in root and shoot. Upon sulfate re-supply, there was no correlation between the activity and expression of the sulfate transporters. Despite the decrease in the abundance of the sulfate transporter transcripts, especially at the onset of the sulfate re-supply, the sulfate uptake capacity was affected very little for up to 96h. There was no relationship between changes in the sulfate or thiol content and activity and expression of the sulfate transporters. Thus, their significance as regulatory signal compounds remains unresolved. The activity and expression of APS reductase, which was enhanced strongly only in the shoots of sulfate-deprived plants, and rapidly decreased again upon sulfate re-supply, corresponded with changes in thiol content, consistent with this pool having a role as a regulatory signal.

Increased anticancer effects of organically-cultivated kale (Brassica oleracea Acephala group) in AGS human adenocarcinoma cells

Increased anticancer effects of organically-cultivated kale (<i>Brassica oleracea</i> Acephala group) in AGS human adenocarcinoma cells

Kale Juice Improves Coronary Artery Disease Risk Factors in Hypercholesterolemic Men

To evaluate the effect of 3-month kale (Brassica oleracea acephala) juice supplementation on coronary artery disease risk factors among hypercholesterolemic men. Thirty-two men with hypercholesterolemia (> 200 mg/dL) were recruited after annual health examinations among the faculty and staff at university. The subjects consumed 150 mL of kale juice per day for a 12-week intervention period. Dietary and anthropometric assessments were performed and blood samples were collected to evaluate biochemical profiles before and after supplementation. Serum concentrations of HDL-cholesterol, and HDL- to LDL-cholesterol ratio were significantly increased by 27% (P<0.0001) and 52% (P<0.0001), respectively. The LDL-cholesterol concentration and the atherogenic index were significantly reduced by 10% (P=0.0007) and 24.2% (P<0.0001), respectively without affecting body mass index, waist and hip circumferences, or nutrient intakes after three months of supplementation. While there was no difference in the concentration of malondialdehyde, significant increase in glutathione peroxidase activity (P=0.0005) were accompanied by a significant increase in the serum selenium level (P=0.0132). It was also found that the responses of these risk factors to kale juice administration were dependent on smoking status. Regular meals supplementation with kale juice can favorably influence serum lipid profiles and antioxidant systems, and hence contribute to reduce the risks of coronary artery disease in male subjects with hyperlipidemia.

Collard Cultivar Evaluations in Northern Florida

Nine collard (Brassica oleracea acephala group) cultivars were evaluated on six experiments over 4 years to determine how well they performed with respect to yield, plant weight, and bolting tolerance. Experiments covered spring, fall, and winter seasons to determine if one cultivar would be useful for all conditions. ‘Top Pick’, ‘Flash’, and ‘Blue Max’ were found to be the best performing cultivars with respect to yield and plant weight. In general, the hybrid cultivars outperformed the open-pollinated cultivars. Only during one experiment were the cultivars subjected to environmental conditions favorable for bolting, but there were no significant differences in incidence of bolting among the cultivars. Although top-performing cultivars were hybrids, the cost associated with hybrid seed must be considered.

Multi-element survey of allotment produce and soil in the UK

In 2004, a survey of 12 metals was carried out in six rural and six urban allotment sites across the UK. A total of 215 samples of vegetables and 36 samples of soft fruit were analysed using ICP–MS, and 51 samples of soil using ICP–OES. On a fresh weight basis, Cu levels in produce ranged 0.119–2.271 mg kg−1. The highest levels measured (in mg kg−1) were Pb 0.164 in a sample of blackcurrants, Cd 0.039 in spinach, Hg 0.003 in curly kale and As 0.025 in raspberries. The lowest concentrations for these metals were below the level of detection (LOD) in numerous samples. The majority of Pt samples were below LOD and all were under the limit of quantification (LOQ). The results of the survey showed that the concentrations of the metals in vegetables, fruit and soils were consistent with previous studies and, generally, at low levels.

The potential of kales as a promising vegetable crop

Sixty varieties of kale (Brassica oleracea acephala group) from Galicia (northwestern Spain) were evaluated in two locations along with four commercial kale varieties. Data on 26 agronomic and morphological traits and five nutritional traits (crude fibre, acid detergent fibre, crude protein, calcium and potassium) were recorded. The objectives of this work were (i) to know the potential ability of kale as an horticultural crop, (ii) to assess the characteristics of local varieties of Galician kale in order to select those with the highest yield and a good adaptation to obtain improved varieties. In most traits, significant differences between locations were found, while varieties × location interaction was not significant for most of them. Significant differences were found among varieties and a high intravarietal variability was noticed in some traits. Galician kale germplasm displayed variability in the most important agronomic traits. They are characterized by their long cycles, their susceptibility to Lepidoptera pests, their good yield and adaptation to Galician conditions and their high calcium content. Four local varieties (MBG-BRS0468, MBG-BRS0476, MBG-BRS0477 and MBG-BRS0494) were the most promising for vegetal and fodder use. One of them showed the best early vigor (MBG-BRS0366) and two of them were the most resistant to Lepidoptera pest (MBG-BRS0060 and MBG-BRS0223). Kale varieties showed a high crude fibre content, and also a high acid detergent fibre, crude protein and calcium content. The varieties MBG-BRS0106, MBG-BRS0281, MBG-BRS0335 and MBG-BRS0464 could be candidates for future breeding programs since they had a good agronomic performance and a high calcium content.

Factors Affecting the Glucosinolate Content of Kale (Brassica oleracea acephala Group)

Kales (Brassica oleracea acephala group) are important vegetable crops in traditional farming systems in the Iberian Peninsula. They are grown throughout the year to harvest their leaves and flower buds. The glucosinolate content of kales is dependent upon the environmental factors, plant part examined, phenological stage of plant growth, and level of insect damage. The objectives of this study were to evaluate the changes in the total and individual glucosinolate concentrations during plant development and to determine if significant variation of glucosinolate levels can be explained by insect pests attack and other environmental factors in four locations in northwestern Spain. The total glucosinolate concentration in leaves of B. oleracea increased with plant age from seedling to early flowering stages. At that stage, the aliphatic glucosinolate content in leaves of B. oleracea declined drastically over time as the content in the flower buds increased. The highest contents of indolyl glucosinolate (glucobrassicin) and of the aromatic glucosinolate occurred in leaves harvested at the optimum consumption stage while flower buds contained the highest concentration of aliphatic glucosinolates, especially sinigrin. Sinigrin is reported to have anticarcinogenic properties. There appears to be a loss of total and individual glucosinolate concentrations related to pest attack. Leaves damaged by lepidopterous pests contained a lower total glucosinolate content (25.8 micromol g-1 dw) than undamaged leaves (41 micromol g-1 dw). The amounts of sinigrin, glucoiberin, and glucobrassicin were also lowest in insect-damaged leaves. Environmental factors such as soil properties and temperature appear to influence the glucosinolate content in leaves although more research on this subject is needed.

Parasitism of &lt;I&gt;Plutella xylostella&lt;/I&gt; L. Feeding on a New Host Plant

The diamondback moth Plutella xylostella L. (Lepidoptera: Plutellidae) is known to be an oligophagous pest on crucifers. Recently, a population of diamondback moths was found to infest sugar snap and snowpea in the Rift Valley in Kenya, causing heavy damage. The effect of resident parasitoids on diamondback moths in snowpea (Pisum sativum L.) was studied in the field. In addition, parasitism of diamondback moths by the newly introduced parasitoid Diadegma semiclausum (Hellen) was evaluated. Snowpea provided an enemy-free space for diamondback moths. Local parasitoids attacked diamondback moths only sporadically and in very low numbers (mean of 0.25 individuals/20 plants during the first study period) on diamondback moths on pea compared with a mean of 15.4 individuals/20 plants on kale (Brassica oleracea acephala L.) However, diamondback moth density was higher on kale (mean of 61.1 larvae/20 plants) than on snowpea (mean of 11.4 larvae/20 plants). Differential diamondback moth infestation and level of parasitism might have been affected by a fungal infection (Ascochyta) of the pea plants. In both crops, the most abundant parasitoid was Oomyzus sokolowskii Kurdjumov. After the release of D. semiclausum, the number of diamondback moths in kale decreased drastically to <2 individuals/20 plants; however, the parasitoid had little effect on diamondback moths on snowpea. Percentage parasitism on snowpea increased from 2.3 to 4%, whereas on kale, it increased from 25.6 to 75.7%. A host plant expansion could be of future advantage for the diamondback moth to avoid higher enemy pressure caused by D. semiclausum.

In vitro binding of bile acids by spinach, kale, brussels sprouts, broccoli, mustard greens, green bell pepper, cabbage and collards

The in vitro binding of bile acids by spinach ( Spinacia oleracea), kale ( Brassica oleracea acephala), Brussels sprouts ( Brassica oleracea gemmifera), broccoli ( Brassica oleracea italica), mustard greens ( Brassica juncea), green bell peppers ( Capsicum annuum), cabbage ( Brassica oleracea capitala) and collards ( Brassica oleracea acephala) was determined using a mixture of bile acids secreted in human bile at a duodenal physiological pH of 6.3. Six treatments and two blank incubations were conducted testing various fresh raw green vegetables on an equal dry matter basis. Considering cholestyramine (bile acid binding, cholesterol lowering drug) as 100% bound, the relative in vitro bile acid binding of various vegetables tested on equal dry matter and total dietary fibre basis was 2–9% and 6–32%, respectively. Bile acid binding for spinach, kale and brussels sprouts was significantly higher than for broccoli and mustard greens. For broccoli and mustard greens binding values were significantly higher those for cabbage, bell pepper and collards. These results point to the health promoting potential of spinach = kale = brussels sprouts > broccoli = mustard greens > cabbage = green bell peppers = collards, as indicated by their bile acid binding on dry matter basis.

Variation in the content of glucosinolates, hydroxycinnamic acids, carotenoids, total antioxidant capacity and low‐molecular‐weight carbohydrates in Brassica vegetables

AbstractBioactive compounds were investigated in genotypes (cauliflower 10, white cabbage 10, curly kale 1) and plant parts of the three crops. The content of most of the major glucosinolates glucobrassicin, sinigrin and glucoiberin differed significantly between cultivars. Samples harvested in 2000 had higher amounts of several glucosinolates than samples from 1999. Within cauliflower the buds of the floret had 1.5 to 2.5‐fold higher concentration of glucobrassicin and 4‐methoxyglucobrassicin than the stalk. In white cabbage several glucosinolates had their highest content in the outer leaves (up to 2‐fold higher). Upper leaves of curly kale contained 5‐fold more of total glucosinolates than lower leaves. Chlorogenic acid was the dominating hydroxycinnamate in curly kale, which also contained at least ten times more of carotenoids (mainly lutein) than white cabbage. Total antioxidant capacity (TAC) assayed with the FRAP method was 0.76 (0.06) µmol/g fw (mean (SD)) in water‐soluble and 0.32 (0.04) in water‐insoluble extracts of cauliflower which was 62–68% higher than in white cabbage. Curly kale contained 6.4 and 6.1 µmol/g fw TAC in water‐soluble and water‐insoluble extracts. TAC did not differ between plant parts. Progoitrin and 4‐hydroxyglucobrassicin were correlated to water‐soluble TAC in white cabbage, probably reflecting a variation in other compounds. Cauliflower contained less glucose, fructose and sorbitol but more sucrose than white cabbage. Curly kale had lower contents of glucose (∼2 times), fructose (∼4–5 times) and sucrose (20 and 36 times, respectively) than cauliflower and white cabbage, while inositol was only found in curly kale. Storage of white cabbage reduced the amount of sorbitol and sucrose. The study shows that cultivar, plant part and storage affect the content of bioactive compounds in Brassica vegetables. The variation between years, as in cauliflower, is due to environmental factors. Since the cultivar ranking order was rather stable for several components the data could provide a basis for the selection of cultivars optimised for valuable health components for fresh market consumption. Copyright © 2005 Society of Chemical Industry

Characterization of Dietary Fiber Lignins from Fruits and Vegetables Using the DFRC Method

Insoluble fiber fractions from 11 fruits and vegetables were investigated for their lignin composition using the derivatization followed by reductive cleavage (DFRC) methodology. To enrich lignin contents and to minimize polysaccharide excess that led to nonanalyzable DFRC chromatograms, the insoluble fibers were degraded by a carbohydrolases mixture. The residues that were found to be representative for the insoluble fiber lignins were analyzed. The investigated fibers differ considerably in their lignin contents and also in their lignin compositions. With the exception of radish fiber, only trace amounts (or none) of the products resulting from p-hydroxyphenyl units were detected. Lignins noticeably differed in the ratio of the DFRC products resulting from syringyl units (S) and guaiacyl (G) units (G/S ratios ranged from approximately 39 to 0.2). The insoluble fiber lignins were classified as G-rich lignins (G/S ratio > 3; carrot, spinach, kiwi, curly kale, radish, and asparagus), S-rich lignins (S/G ratio > 3; rhubarb), or balanced lignins (0.3 < G/S ratio < 3; pear, apple, small radish, and kohlrabi). Information about further structural characteristics, for example, cinnamyl endgroups, was obtained from the analysis of DFRC minor products.

Antioxidant Activity and Total Phenolic Content of Kale Genotypes Grown in Kashmir Valley

Green leafy vegetable extracts of six genotypes of kale (Brassica oleracea acephala) were evaluated for ascorbic acid, carotenoids, total phenolics and antioxidant activity. Ascorbic acid ranged from 142 mg per 100 g in Wappal Hakh to 164 mg per 100 g fr wt in Knol khol. Wild genotypes Wappal and Pumb, had significantly high phenolic content (285 and 227 mg per 100 g fr wt) and possessed highest antioxidant activities (840 and 780 µmol FRAP per g fr wt) than cultivated genotypes. A positive and strong correlation (R2 = 0.807) between total phenolic content and antioxidant activity suggests that kale has enormous potential to enhance the antioxidant potential of our daily food supply. Wild genotypes, Wappal and Pumb can be incorporated into the breeding programmes in order to increase the antioxidant potential of cultivated varieties.

EFFECT OF THALLIUM FRACTIONS IN THE SOIL AND POLLUTION ORIGINS ON Tl UPTAKE BY HYPERACCUMULATOR PLANTS: A KEY FACTOR FOR THE ASSESSMENT OF PHYTOEXTRACTION

Phytoremediation is often discussed as a means of extracting trace metals in excess in the soil, but to increase its efficiency a better understanding of the factors controlling plant uptake is required. The main objective of this study was to examine the effect of origin (anthropogenic vs. geogenic) and mobility of thallium (Tl) in the rhizosphere on Tl uptake. Two Tl-hyperaccumulating Brassicaceae species, kale (Brassica oleracea acephala L. cv. Winterbor F1) and candytuft (Iberis intermedia Guers.), were grown in a rhizobox system to investigate the dynamics of Tl in the rhizosphere soil. Four different soils were used. Two soils contained high Tl amounts due to anthropogenic sources (emissions from a cement plant and mining activities). High Tl content in the two other soils was due to a high rock content (geogenic origin). On completion of growth in the rhizoboxes, the depletion of Tl in seven different chemical fractions, determined by sequential extraction, was compared to the plant uptake. Most of the Tl taken up was derived from the so-called “easily accessible” fractions in both soils with geogenic Tl as well as in the soils polluted by mining activities. Due to the small amounts of easily accessible Tl in the geogenic soils, Tl uptake by Brassicaceae was low. On the other hand, for the air emission-polluted soil, a high depletion of Tl from “less accessible” fractions was observed in addition to depletion of the easily accessible fractions. Hence, the latter soil demonstrated the highest potential for effective soil decontamination by phytoextraction within an appropriate time frame.

Influence of Soil and Nutrient Management on Growth and Quality of Collards

High temperature and humidity during summer months in the southeastern U.S., in addition to crop nutritional status, are suggested to be the primary reasons for tipburn incidence in collards (Brassica oleracea Acephala Group) adversely affecting their marketability. A 2-year study was conducted to evaluate the efficiency of grower's standard practice (GSP), GSP + gypsum, and a programmed-release fertilizer (PRF) under conventional and deep tillage on collard yield and tipburn incidence. Subsoiling significantly increased yield over conventional tillage. Nutrient supply through PRF did not increase the yields; however, it resulted in either similar or higher levels of macro- and micronutrient levels both in soils and collard tissue compared to GSP and GSP + gypsum treatments. The occurrence of tipburn in collards is dependent on several factors, including nutritional, physiological, and environmental stresses. Regression analyses of tipburn ratings at harvest time and the soil and tissue nutrient content suggested that 47% of the variation could be attributed to soil and tissue levels of sulfur (S), zinc (Zn), and phosphorus (P). It is important, therefore, to ensure an optimum supply of nutrients to the plants to maintain the quality of the yields. The advantage of PRF in sandy soils, and identification of other factors affecting the tipburn in collards should be further investigated.