Interstock effects on growth,photosynthesis and mineral nutrition of ‘delicious’ apple seedlings

Tree growth, photosynthesis, and the mineral nutrient content were investigated in ‘Redchief Delicious’ scions double worked on seedling rootstock with a variety of interstocks. The interstocks used were ‘Redchief Delicious’, M9, and a range of F. generation hybrids with internodes designated short, medium and long. The long internode graft union consistently produced more growth and dry weight per tree than the other interstocks. The ‘Redchief Delicious’ interstock had an unexplained negative effect on leaf, shoot and new root dry weight. There was no effect of interstock on photosynthesis initially (56 days) however photosynthesis increased with shorter nodal interstocks after 111 days. There were significant differences in scion and interstock bark elemental composition due to interstock combination. However, leaf composition varied slightly among the different interstock combinations. Manganese levels, independent of tissue type, did not vary between interstocks.     

Effect of nitrogen and phosphorus on ‘delicious’ apple trees grown in caliche soil in the greenhouse

Abstract

In a greenhouse study, mono‐ammonium phosphate applications to ‘Delicious’ (Oregon spur cv) apple trees, Malus domestica Borkh., improved a low‐vigor condition associated with a caliche soil. The moderate rate of mono‐ammonium phosphate (6 grams per tree) resulted in trees with greater shoot extension, leaf numbers, a higher percent leaf phosphorus, and less purple leaf margins or spots than other soil treatments or the control. By September, trees treated with the highest rate of mono‐ammonia phosphate (12 grams per tree) had the highest level of leaf phosphorus and significantly higher levels of leaf phosphorus than all forms of nitrogen‐only fertilizer (ammonium nitrate, ammonium sulfate, calcium nitrate, and urea). In most cases, applications of the nitrogen‐only fertilizers, reduced leaf phosphorus levels throughout the experiment.     

Solution pH influences on growth and mineral element concentrations of ‘Waimanalo’ papaya seedlings

Two sand culture experiments were conducted to determine the influence of substrate pH on ‘Waimanalo’ papaya seedling growth, morphology, and mineral element nutrition. The seedlings were grown in clear, plastic tubes 7 cm in diameter and 21 cm in height with the rooting substrate being silica sand. The substrate was drenched daily with a complete nutrient solution. The solution was adjusted to target the pH at 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, or 9.0. Direct seeded plants were used in the first study and plants were harvested after 9.5 weeks of growth. Transplants were used in the second study, and plants were harvested after four weeks of growth. Dry mass of plants was relatively unaffected by substrate pH within the range of 4.0 to 9.0. In both studies, however, dry mass of plants receiving a target pH of 3.0 was reduced compared to those plants receiving the other pH level nutrient solutions. This response pattern was similar for other characteristics such as canopy/root ratio, total root length, root extension rate, lateral root thickness, and root density. Various root characteristics were decreased more by pH of 3.0 than other canopy characteristics. Unit leaf area per unit root length was greatly increased for plants receiving the pH 3.0 nutrient solution, indicating increased susceptibility to drought stress. Root accumulation of manganese (Mn), zinc (Zn), and iron (Fe) was markedly greater than the canopy accumulation. The influence of pH on mineral element concentrations was similar for roots and canopy for all elements except magnesium (Mg). Canopy tissue, but not root tissue, accumulated more Mg at lower pH than higher pHs. The greatest influence of pH on mineral element concentration was for iron (Fe). The concentration of Fe at pH of 3.0 was almost three times the concentration at the other pHs. No visual symptoms of mineral deficiency and/or toxicity were evident. These results indicate that the growth and morphology of papaya seedlings provided with complete nutrient solution are relatively unaffected by pH within the range of 4.0 to 9.0.     

Midsummer copper sprays have no effect on ‘delicious’ apple fruit color grade or typiness

Recent reports suggested that multiple midsummer copper (Cu) sprays could improve the proportion of apple fruit (Malus × domestica Borkh.) being packed in the reddest market color grades. We conducted a three‐year field experiment in a low‐Cu orchard with a history of poor fruit coloring. We applied multiple mid‐summer sprays of Cu sulfate and basic Cu sulfate in 1994 and 1995 to ‘Bisbee Delicious’ and ‘Oregon Spur II Delicious’ apple trees. Plant tissue nutrient levels, fruit color grade, and fruit typiness were evaluated in the years of application and the following year. The Cu sprays increased leaf Cu in the years of application; however, leaf Cu in the Cu‐sprayed plots returned to or very near to background concentrations in the year after sprays were terminated. The Cu treatments did not increase the proportion of fruit in the reddest market color grades or influence five fruit typiness indices of either apple cultivar. Although midsummer Cu sprays may not enhance apple fruit red color or typiness, they may be useful for increasing overall tree Cu status, particularly for long‐season cultivars which are harvested too late for postharvest sprays to be effective.     

Recommended prebioom copper spray has no beneficial effect on ‘delicious’ apple tree copper status or fruit typiness

Three field experiments were conducted to evaluate a new commercial recommendation to add small amounts of a Cu(OH)₂‐based fungicide, Kocide 101, to prebioom zinc (Zn) nutrient sprays in order to enhance ‘Delicious’ apple tree copper (Cu) status and improve fruit typiness. Treatments were (1) single prebioom spray of basic Zn sulfate in combination with varying rates of added Cu as Kocide; (2) single spray of Kocide alone at pink timing; and (3) single silver‐tip spray of Zn sulfate in combination with varying rates of Kocide or a more soluble Cu sulfate‐based product. The Cu sprays applied at silver‐tip had little or no effect on flower cluster Cu concentration at full bloom. Kocide applied at green‐tip and later increased flower cluster Cu. None of the Cu sprays influenced midsummer leaf Cu concentration. The Cu sprays had no beneficial effect on fruit mass or on any of five fruit typiness indices. The experimental results indicate that there are no detectable nutritional or fruit typiness benefits resulting from adding Kocide to Zn sprays at any prebioom timing, or from adding Cu sulfate to Zn sprays applied at silver‐tip bud stage.     

Growth of apple seedlings on sludge‐amended soils in the greenhouse

Abstract

Open pollinated ‘York Imperial’ apple (Malus domestica Borkh.) seeds were germinated and grown for a period of 7 months in: (1) sand with complete nutrient solutions added; (2) limed and unlimed soil, (3) limed and unlimed soil amended with two different sewage sludges at rates of 25, 50 or 100 dry kg ha^‐1. A third composted, lime stabilized sludge was added either sieved or non‐sieved (to remove wood chips) at the same rates. The sludge materials used were: (1) a high metal, composted sludge from Baltimore, MD (BALT); (2) a high Cd sewage sludge (CITY) and (3) a low metal, composted sewage sludge from Washington, D.C. (DC).

Germination was unaffected by treatments. After 7 months, the best growth was obtained from the sand plus nutrient solution media. Two of the three sludge materials increased seedling growth over that of the soil, either limed or unlimed. The BALT compost treated soils produced the lowest growth, particularly when unlimed. Elevated tissue metal levels indicated that Mn, Zn, Cu and Ni were the probable causes of reduced growth noted from the BALT compost treatment. The use of soil with or without low metal sludges as media for early apple seedling growth when compared to standard sand culture is not recommended.     

Effect of aluminum uptake on growth and enzyme activity in Pisum sativum var. ‘Alaska’ and ‘Little Marvel’

It is usually assumed that plant tissue responses to nutritional elements are due to specific genetic differences that may exist either between inbred or closely related species. Little Marvel (dwarf) and Alaska (normal) varieties of 14‐day old pea seedlings were treated with four different concentrations of Al‐containing nutrient solution (0.0mM, 0.2mM, 0.6mM and distilled H₂O), prior to being exposed for 14 days to either DARK, LIGHT, or UV. Selected tissues (root tip, main root, main stem and proximal stem) were bioassayed for peroxidase and polyphenol oxidase enzyme activities, fresh wt vs. dry wt, water uptake and stem growth. The present study suggests that Little Marvel and Alaska pea tissue responds to high toxicity levels of Al by demonstrating an enhancement of enzymic activity. Tissue weight, growth and water uptake also show differential tissue specificity in both Little Marvel and Alaska tissue, in terms of Al toxicity response, given a particular external exposure.     

Nitrogen,phosphorus, and potassium effects on pre‐ and post‐transplant growth of salvia and vinca seedlings

Pre‐ and post‐transplant growth of bedding plants is affected by seedling nutrition. However, there is little information available on how seedling nutrition affects the growth of ornamental bedding plants. In this study, we quantified the effects of nitrogen (N) (8 to 32 mM) and phosphorus (P) and potassium (K) concentration (0.25 to 1 mM) of the seedling fertilizer on pre‐ and post‐transplant growth and nutrient element content of salvia (Salvia splendens F. Sellow ex Roem. & Schult.) and vinca (Catharanthus roseus L.) seedlings. Shoot growth of salvia and vinca increased with increasing concentrations of N in the pre‐transplant fertilizer and these differences lasted until the end of the study at 15 days after transplanting. Pre‐transplant root dry mass of these species was not affected by the N concentration of the fertilizer, but root dry mass at 12 days after transplanting was positively correlated with the N concentration of the pre‐transplant fertilizer. Increasing N concentrations in the seedling fertilizer increased tissue N levels of salvia and decreased tissue K level of vinca at transplanting. Increasing P and K concentrations in the pre‐transplant fertilizer increased tissue P level of salvia and P and K levels of vinca, but had little effect on seedling growth. Leaf area and root dry mass at transplanting decreased slightly with increasing P and K concentration in the fertilizer. There were no lasting effects of pre‐transplant P and K concentration of the fertilizer. These results indicate that salvia and vinca seedlings can benefit from high concentrations of N (up to 32 mM) in the fertilizer, while only low concentrations of P and K (0.25 mM) are needed.     

Influence of mid‐summer boron sprays on boron content and quality indices of ‘delicious’ Apple 1

Boron (B) is required for optimal yield and quality of apple fruit (Malus domestica Borkh.) but may impair fruit quality if present in excessive amounts. A field experiment was conducted to examine the effects of a single mid‐July foliar B spray (0, 11.3, 22.6 g B/tree) on the B content and postharvest quality indices of 220‐gram ‘Starking Delicious’ apples. Fruit B concentration was positively related to B application rate and ranged from 9 to 55 mg/kg dry mass (1.3 to 7.7 mg/kg fresh mass). The relative B increases were greater in the core and inner cortex than in the outer cortex and skin, suggesting that some of the applied B entered the fruit through the tree vascular system. Increasing fruit B concentrations caused minor changes in fruit external color indices L and b and internal color index b but had no effect on firmness, soluble solids concentration, titratable acidity, starch index, external color index a, or internal color indices L and a. None of the effects were of horticultural significance. Most fruit quality indices were influenced by postharvest sampling time and reflected typical postharvest ripening patterns. The results suggest that ‘Delicious’ apple quality is relatively insensitive to high fruit B concentrations.     

Limestone and gypsum effects on calcium nutrition of ‘Florunner’ and ‘NC‐7’ Peanuts

Abstract

Minimum sufficiency levels of hull and seed Ca for maximum yield and grade of runner or Virginia type peanuts (Arachis hypogaea L.) have not been established and there is limited information on single and combined effects of limestone and gypsum on production and quality of peanuts. Field experiments were conducted on runner and Virginia type peanuts to study single and combined effects of limestone and gypsum on yield and grade, and to attempt to establish minimum sufficiency levels of hull and seed Ca for maximum yield and grade of each type. Gypsum treatments, O, low, medium, and high rates, were superimposed on residual limestone rates on three sites with ‘Florunner’ (runner type) and on one site with ‘NC‐7’ (Virginia type) peanuts. Yield and grade of Florunner peanuts were not increased by limestone or gypsum treatments on any site even though soil Ca concentrations (Mehlich 1) ranged from 152 to 200 mg/kg among the sites. These levels were lower than the Georgia recommended minimum sufficiency value of 250 mg/kg. However, yield and grade of ‘NC‐7’ peanuts were increased by limestone or gypsum, but maximum yield occurred only where gypsum was applied even with soil Ca levels of 682 mg/kg. The minimum hull Ca level of 1.2 g/kg and seed Ca of 0.42 g/kg were sufficient for Florunner peanuts since yields and quality were not increased by limestone or gypsum application. Maximim yield and grade were achieved with Florunner at leaf, hull, and seed Ca concentrations of 13.2, 1.2, and 0.42 g/kg as compared with 26.0, 1.9, and 0.58 g/kg for NC‐7, respectively. These data show that NC‐7 has a higher Ca requirement than Florunner.     

Mineral nutrition during establishment of golden delicious ‘smoothee’ apples on dwarfing rootstocks and interstems

This study was conducted to determine the influence of 4 interstems (EM.27 EMLA, Mark, M.9 EMLA, and EM.26 EMLA) and 8 rootstocks (EM.27 EMLA, Mark, M.9 EMLA, EM.26 EMLA, M.7A, MM. 106 EMLA, MM. 111 EMLA, and seedling) with and without interstems on foliar element concentrations [nitrogen (N,) phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), iron (Fe), zinc (Zn), boron (B)] of the Golden Delicious ‘Smoothee’ (Malus domestica, Borkh). The trees were planted in 1990 and the experiment was conducted until 1996. Soil pH was low (pH=5.9) before planting but liming raised the pH to 6.5 by the 4th year after planting. Soil P was adequate, K and Mg were high, and Ca was low based on local recommendations for apples. The year by year variation in foliar element concentrations was much higher than rootstock and interstem effects. Differences among interstems and rootstocks were important as foliar element concentrations approached those of deficiency or toxicity. In this study, K decreased to deficiency concentrations by the end of the experiment except for seedling rootstocks, which slightly increased. Foliar Ca was deficient for all interstems and rootstocks at the start of the experiment, but increased extensively for M.9 EMLA and EM.26 EMLA rootstocks across years. Foliar Mn increased to nearly toxic concentrations (300 μg g^‐1) in EM.27 EMLA and Mark rootstocks, whereas the other rootstocks did not. No deficiency or toxicity symptoms were noted for any elements during this study. These results indicate that a single range of foliar nutrient concentrations can be used as an aid for determining fertilization rates for the apple rootstocks and interstems used in this study. However, individual rootstocks vary in the rate at which they approach toxicity and deficiency concentrations, which needs to be known to prevent mineral nutritional related problems in commercial apple orchards.     

Effect of root pruning and nitrogen fertilization on growth of young ‘fuji’ apple (Malus domestica borkh.) trees

This study examined the effect of root pruning (RP) and nitrogen fertilization (NF) alone or in combination (RP-NF) on growth properties of 3-year-old ‘Fuji’ apple (Malus domestica Borkh.) trees. The results of pot experiments showed that the trees were sensitive to RP and NF alone or in combination in terms of root architecture, leaf photosynthesis, and canopy growth. Compared with the control, NF and RP-NF increased root length density and tips, while RP and RP-NF decreased root surface area and volume. RP alone reduced coarse root length (2.0–4.0 and >4.0 mm diameter), while RP-NF simultaneously increased fine root length (≤1.0 mm diameter) and reduced coarse root length. Moreover, RP increased leaf chlorophyll content and transpiration rate, while RP-NF increased net photosynthetic rate and water use efficiency. RP-NF resulted in no differences in dry matter weight, root-shoot ratio, or leaf area compared with the control. Inhibiting vegetative growth by RP-NF provided an effective way to improve water use efficiency of young apple trees.     

Influence of nitrogen on leaf chlorophyll content and photosynthesis of ‘Golden Delicious’ apple

Abstract

The aim of the present study was to estimate the influence of different rates of soil-applied nitrogen on leaf N and chlorophyll content and photosynthesis in ‘Golden Delicious’ apple trees. Three different treatments were included: the trees were either fertilized with 80 kg N ha^?1 (N-80), 250 kg N ha^?1 (N-250) or left unfertilized (CON). Fertilization increased leaf nitrogen content, with a more prominent effect in high N application level treatment. In all treatments, a slight seasonal decrease in leaf nitrogen content was observed. N-250 treatment resulted in higher chlorophyll content; a similar effect was found late in the season for N-80 treatment. Measurements of A-C _i curves, performed on spur leaves, revealed a higher CO₂ saturated photosynthetic rate in N-250 trees compared with low application level fertilized or unfertilized trees. No effect of N fertilization on carboxylation efficiency was found, as revealed by comparisons of the initial slopes of A-C _i curves. The lack of positive effect is rather surprising, since the leaf N content was efficiently increased with application of fertilizer. Obviously, the existing pool of leaf nitrogen in non-fertilized trees does not limit Rubisco activity and efficiency.     

Influences of water pH,alkalinity and acid additions on growth and nutrient relationships in chrysanthemum morifolium ’bright golden anne‘ 1

Growth of Chrysanthemum morifolium ‘Bright Golden Anne’ was assessed after application of irrigation water containing five alkalinity levels (0, 100, 250, 500, 1000 mg/liter bicarbonate) in a greenhouse study. Irrigation water having alkalinity levels exceeding 500 (week 12)or 1000 (week 6) mg/liter bicarbonate affected plant height and fresh and dry weights. High levels of irrigation water alkalinity altered nutrient availability in the growing medium and plant tissue nutrient content. This was attributed to a rise in growing medium pH. Between 6 and 12 weeks, the critical level of alkalinity in water that altered growing medium nutrient availability and plant growth decreased from 1000 to 500 mg/liter bicarbonate. Acid additions improved plant growth for the water treatment containing 500 mg/liter bicarbonate. Sulfuric acid was the most effective acid treatment.     

Effect of calcium spray materials,rate, time of spray application,and rootstocks on fruit quality of ‘red’ and ‘golden delicious’ apples

Calcium (Ca) spray materials improved fruit quality as measured by control of bitter pit, fruit finish (appearance), increased red skin color, reduced incidence of scald, increased juiciness, texture, and fruit firmness of ‘Red’ and ‘Golden Delicious’ apples (Malus domestica, Borkh.). Concentrations of Ca in leaf and fruit tissues were increased by Ca sprays, especially calcium chloride (CaCl₂)‐containing spray materials. Improved fruit firmness and control of bitter pit occurred for either standard recommended or high rates of Ca spray materials. At high rates of application, the only significant difference that occurred between early and late applications of Ca spray materials was that less leaf injury occurred with the early applications. Unsprayed ‘Red Delicious’ fruit from M.7 rootstocks had greater fruit peel Ca concentrations and a lower incidence of bitter pit but smaller fruit than fruit from trees on M.26 rootstocks. The above information is strong evidence that Ca sprays are important for the improvement of apple quality.     

Effects of vesicular‐arbuscular mycorrhizas and phosphorus on water status and growth of apple

Apple (Malus hupehensis Rehd) seedlings were grown in sterilized and non‐sterilized soil with or without phosphorus (P) added and inoculated by VA mycorrhizal (VAM) fungi (Glomus versifome Daniels et Tappe and Glomus macrocarpum Tul et Tul). In sterilized soil, the VAM infection increased the transpiration rate (Tr.) of the leaves, reduced the stomatal resistance (Sr.) and the permanent wilting percentage (PWP) and enhanced the rate of recovery of the plant from the water stress and the plant growth (e.g. leaf number, stem diameter and dry weight). It also increased absorption of most minerals, especially Zn and Cu by the roots and weakened the P‐Cu and P‐Zn interactions. Phosphorus fertilization had some positive effects on the water status, P nutrition and growth, but it reduced the Cu concentration. VAM improved the water status and enhanced drought tolerance of the trees by enhancing absorption and translocation of water by the external hyphae. The efficiency of inoculation in nonsterile soil was not obvious.     

Effects of nitrogen forms and calcium amounts on growth and elemental concentration in Rosa hybrida cv. ‘Vendentta’

An experiment was conducted to investigate the effects of calcium and nitrogen on quality and quantity of Rosa hybrida in hydroponic culture, using factorial complete randomized design with different levels of ammonium-N (0, 2.5, and 5 mM) and calcium (1.6 and 4.8 mM). The results indicated that ammonium-N concentration of 2 mM increased the number of flowers, length of pedicles, and fresh weight of flower stem per plant. 5 mM of ammonium-N caused a significant decrease in most of the measured characteristics. Increase in calcium concentration enhanced nitrogen, calcium, manganese, and boron; while, potassium, zinc, and copper decreased in the leaf. Flower diameter and fresh weight of flower stems per plant increased significantly. With application of ammonium in the nutrient solution, calcium and potassium concentration in the leaf decreased, whereas phosphorus, zinc, manganese, iron, and boron significantly increased. Therefore, application of 2.5 mM ammonium-N and 4.8 mM calcium are recommended.     

Effects of rootstock and thinning on yield,fruit quality and elemental composition of ‘Redspur Delicious’ apple

Abstract

Influence of two rootstocks and five levels of hand thinning (fruit spacing) on yield, fruit quality at harvest and after storage, and leaf and fruit elemental composition of ‘Redspur Delicious’ apple (Malus domestica Borkh.) were studied. Trees on M.7 rootstock had a higher yield with heavier and firmer fruit at harvest than those on M.26. Trees on M.7 had significantly lower leaf and fruit N which resulted in a darker fruit color than those on M.26 rootstock. Fruit from trees on M.26 had a higher soluble solids concentration (SSC) at harvest than those on M.7. Leaf and fruit potassium (K) increased but fruit calcium (Ca) decreased with an increase in fruit spacing. Thinning fruit to 10 cm or 18 cm spacing, depending on market demand for fruit size, is recommended for improvement of fruit quality. Fruit weight and quality was improved with 18 cm fruit spacing without a significant decrease in yield, while thinning fruit further than 18 cm apart reduced yield without a significant change in the fruit weight or quality.     

Whole fruit mineral element content and respiration rates of harvested ‘delicious’ apples

Whole fruit mineral element analysis is used commercially in Great Britain to predict postharvest apple fruit quality and storage life. Similar commercial programs are under development in Washington State; however, mineral element concentration guidelines are not available for important Washington‐grown cultivars. The current study used fruit respiration rate as a criterion for evaluating optimal whole fruit mineral element concentration. ‘Wellspur Delicious’ apple trees (Malus domestica Borkh.) were treated with four biweekly sprays of D, 4.1 and 13.5 kg CaCl₂/ha. Fruit of uniform diameter (7.65 to 8.05 cm) were harvested. Four intact single‐fruit samples per treatment were placed into individual respiration chambers maintained at 20°C. Humidified CO₂‐free air was continuously pumped into the chambers. Evolved C0₂ was trapped in NaOH and analyzed by titration. Evolution of C0₂ was measured for 38 days after which the fruits were analyzed for whole fruit Ca, N, Mg, P and K concentrations. The C0₂ evolution data was analyzed by linear regression to generate average respiration rates. The preharvest CaCl₂ spray treatments did not influence whole fruit Ca concentrations or respiration rates. The respiration rates were not influenced by mineral element concentration or selected ratios of concentrations. The Ca concentrations in the fruit (> 300 mg/kg dry mass) appear to have been sufficiently high to produce uniform low respiration rates and to mask possible influences of the other elements. The results suggest that whole fruit mineral element analysis may not be a sensitive indicator of average respiration rates of ‘Delicious’ apples during ripening.     

Salinity effects on growth analysis and nutrient composition in four grain legumes‐rhizobium symbiosis

The effect of salinity on growth response, nitrogen (N) fixation and tissue mineral content was investigated for four legumes: faba bean (Vicia faba L), pea (Pisum sativum L), soybean (Glycine max L), and common bean (Phaseolus vulgaris L). Plants were grown in a vermiculite culture system supplied with a N‐free nutrient solution with the addition of 0, 50, and 100 mM NaCl. Plants were harvested at the beginning of the flowering period and the dry weights of shoots and roots and acetylene reduction activity (ARA) were evaluated at the same time plant tissues were analysed for N, potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na) contents.

The depressive effect of saline stress on ARA of nodules was directely related to the salt induced decline in dry weight and N content in shoots. Growth inhibition by NaCl treatments was greater for the pea than for other legumes, whereas the soybean was the most salt‐tolerant Saline stress also affected the N content in shoots and roots. In general the N content accumulated in the shoot and Na in the roots of the four legumes tested, while K accumulated both organs. The acquisition of other macronutrients differed according to the legume species. The legumes most sensitive were P. sativum and V. faba which accumulated Ca in shoot and Mg both in the shoot and the roots. On the contrary, in G. max and P. vulgaris, the two most salt tolerant legumes, accumulated Mg in the roots and Ca in both vegetative organs. Our results suggest a relationship between the salt‐tolerant range in legumes and the macronutrient accumulation in vegetative organs.