摘要:

Loropetalum(L.chinense)cv ‘Blush’, ‘Burgundy’, and ‘Pizzazz’ were grown for 16 months using different rates and application schedules of a 17–7–12 slow‐release fertilizer. Rates were45,68,or 91 g pot1, each applied once in the Spring, or as a split application, half in the Spring, and half in the Fall. A simple format for reporting fertility, methodology used in tissue sampling, and analytical methodology was developed and used. Fertilizer treatments did not affect significantly growth and color ratings 4 and 12 months after potting (p>0.30). ‘Burgundy’ was significantly the fastest growing cultivar. Yet, all plants from all treatments and cultivars were of commercial quality 12 months after potting. Foliar nutrient content was significantly affected by fertilization treatment for most of the essential elements (p<0.03), but not by cultivar (p>0.10). However, differences due to fertilizer treatments were of limited practical importance as they did not follow the trends in fertilizer rates. Based on these results, sufficiency ranges (% for macronutrients and ppm for micronutrients) were proposed forLoropetalumwhen the plant‐part sampled was the healthy leaves from the terminal 10 to 15 cm of 4 to 6 branches, without any woody tissue: 1.10<N<2.30; 0.10<P<0.30; 0.50<K<1.00; 0.70<Ca<1.50; 0.10<Mg<0.20,5<B<20; 5<Cu<10;20<Fe<80; 10<Mn<40; and10<Zn<40.

ISSN:0190-4167    

DOI:10.1080/01904169909365756

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Pansies are one of the most popular annual bedding plants in the United States. Growth and uptake of essential nutrients as influenced by N‐form ratio was evaluated in pansy as well as what role pansy nutrition plays in the protection of pansy against feeding damage by white‐tailed deer provided by selected repellents. Plants were grown under three N‐form ratios: 100:0, 50:50, and 0:100NO3:NH4. Dry weight was highest for pansy treated with 100:0 and lowest for plants treated with 0:100 NO3:NH4Mean quality ratings were 4.07 for pansies grown with 100:0,1.80 for pansies grown with 50:50, and 0.78 for pansies grown with 0:100. Potassium (K), magnesium (Mg), and manganese (Mn) content was lower in plants treated with 0:100 than in those treated with 100:0. Ammonium may have competed with these cations for uptake. Boron (B), copper (Cu), molybdenum (Mo), and aluminum (Al) content was highest in plants treated with N‐NH4. There was no significant difference shown in nutrient levels caused by repellent treatments. Feeding damage was shown to be affected by N‐form ratio only on Day 3 of the study. Of the three repellent treatments [Deer and Rabbit Repellent (Thiram), Deer Away purrescent egg spray, and no spray], Thiram provided the greatest protection to pansies over the study period.

ISSN:0190-4167    

DOI:10.1080/01904169909365757

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Zinc (Zn) fertilizer application has increased during the past three decades. This increase has created the need for more information regarding the availability and agronomic effectiveness of Zn containing fertilizers because differences of opinions exist relating the relationships between Zn water solubility and plant availability. Plant availability of eight commercialized Zn fertilizer materials having different water solubilities was measured under greenhouse conditions. Corn(Zea maysL.) plants were grown for 40 days in a soil (loamy, mixed, mesic arenic Ustollic Haplargid) amended with lime to two pH's: 6.3 and 7.4. To evaluate the effect of pH, some Zn fertilizers were used at both soil pH levels while all Zn fertilizers were used in the pH 7.4 soil. The experimental design was a factorial combination of pH, Zn fertilizers, and Zn rates of 0,2.1,4.2,8.4 mg Zn kg−1soil. Dry matter production and Zn uptake increased significantly when the soil pH decreased from 7.4 to 6.3. The highest dry matter production was obtained with ZnSO4(ZnSO4H2O, 99.9% total water soluble Zn), Zn20 (Zn oxysulfate, 98.3% total water soluble Zn), and Zn27 (Zn oxysulfate, 66.4% total water soluble Zn). While ZnFe (Zn iron ferrite, 0.3% total water soluble Zn), ZnK (Zn oxide, KO61, 1% total water soluble Zn), and ZnOS (Zn oxysulfate, 0.7% total water soluble Zn) were less effective followed by Zn40 (Zn oxysulfate, 26.5% total water soluble Zn) and ZnOxS (Zn oxysulfate, 11% total water soluble Zn). The same trend was observed for Zn concentration and uptake. Regression correlations showed that the higher the water solubility, the more effective the Zn fertilizer in increasing dry matter production. Assuming that 5 to 10 kg Zn ha−1are the rates commonly recommended, about 50% water soluble Zn is required to adequately supply the crop's needs. Lower fertilizer rates were needed as Zn solubility increased. The cadmium (Cd) and lead (Pb) concentrations and uptakes in corn forage were not significant for any of the sources and rates.

ISSN:0190-4167    

DOI:10.1080/01904169909365758

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Two tomato[Lycopersicon esculentum)cvs. Blizzard and Liberto, were grown hydroponically in a Controlled Temperature (CT) room for five weeks to investigate the effectiveness of foliar application of supplementary iron (Fe) to the leaves of plant grown at high zinc concentration (5 mg L−1). Zinc (Zn) concentrations were 0.5 or 5 mg L−1in complete nutrient solution. One week after application of Zn at 5 mg L−1, supplementary iron ( 28 mg L−1for a week and 56 mg L−1for a week) was supplied via leaves to the plants grown at 5mg L−1Zn. The plants grown at 5mg L−1Zn produced less dry matter and chlorophyll than those at 0.5mg L−1for both cultivars. Foliar application of supplementary iron resulted in increases in dry matter and chlorophyll concentrations for both cultivars. These increases were greater in Liberto than in Blizzard. Zinc concentration in plant tissues increased to toxic levels for both cultivars in the high zinc treatment. Application of supplementary Fe as a foliar spray decreased Zn concentration in the leaves and roots of plants grown at high Zn, but its concentrations were still at detrimental levels. Iron concentration in leaves declined to the deficient level in the high (5 mg L−1) Zn treatment, but was markedly increased in the roots. Application of supplementary Fe corrected Fe deficiency in leaves of plants grown at 5mg L−1Zn and reduced root Fe concentrations.

ISSN:0190-4167    

DOI:10.1080/01904169909365759

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Field experiments were conducted during 1994–1995 in seven apple (Malus spp.)orchards located in the southwest of Finland (the mainland and the Åland Islands). The cultivars were ‘Transparente Blanche’, ‘Samo’, ‘Melba’, ‘Raike’, ‘Red Atlas’, ‘Åkerö’, ‘Aroma’, and ‘Lobo’. Leaf samples from branches bearing fruits (BF) and not‐bearing fruits (BNF) were collected two times during the growing seasons. Fruit samples were picked about one week before commercial maturity. Macronutrient concentrations in fruits and leaves, fruit diameter and juice pH, titratable acidity (TA) and soluble solids concentrations (SSC) were determined. Leaf nitrogen (N), phosphorus (P), and potassium (K) were higher, but calcium (Ca) and magnesium (Mg) were lower in BNF. Branch types (BF and BNF) were closely related in leaf N, P, and Ca, but not in leaf K and Mg at the first sampling time. Fruit N, P, K, and Mg were closely related to each other but not to fruit Ca. Mean fruit N and Ca and leaf P and Mg were low compared with the recommended levels. Relationships between fruit and leaf nutrient concentrations were found only in P and Mg. Fruit diameter increased and juice SSC decreased with increasing leaf N concentration. Fruit P declined with increasing fruit diameter and juice TA increased and SSC/TA decreased with increasing leaf P and Ca concentrations.

ISSN:0190-4167    

DOI:10.1080/01904169909365760

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Silicon (Si) is one of the most abundant elements found in the earth's crust, but is mostly inert and only slightly soluble. Agriculture activity tends to remove large quantities of Si from soil. Sugarcane is known to absorb more Si than any other mineral nutrient, accumulating approximately 380 kg ha−1of Si, in a 12‐month‐old crop. Sugarcane (plant growth and development) responses to silicon fertilization have been documented in some areas of the world, and applications on commercial fields are routine in certain areas. The reason for this plant response or yield increase is not fully understood, but several mechanisms have been proposed. Some studies indicate that sugarcane yield responses to silicon may be associated with induced resistance to biotic and abiotic stresses, such as disease and pest resistance, Al, Mn, and Fe toxicity alleviation, increased P availability, reduced lodging, improved leaf and stalk erectness, freeze resistance, and improvement in plant water economy. This review covers the relationship of silicon to sugarcane crop production, including recommendations on how to best manage silicon in soils and plants, silicon interactions with others elements, and laboratory methodology for determining silicon in the soil, plant and fertilizer. In addition, a future research agenda for silicon in sugarcane is proposed.

ISSN:0190-4167    

DOI:10.1080/01904169909365761

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Soluble salts found in wastewater can be toxic when used for irrigation of forages. Thus, two greenhouse experiments were conducted to investigate effects of saline [CaCl2NaCl (3:1, w:w)] treatments on soil chemical properties and ‘Dekalb FS‐5’ forage sorghum[Sorghum bicolor(L.) Moench].Treatments for the first experiment consisted of a nonsaline control or 500 mL of a solution with an electrical conductivity (EC) of 10 dS m−1applied once. In the second experiment, treatments were salinity levels of 1.7,3.5,5.2,8.5, and 12.2 dS m−1, applied in non‐nitrogenous Hoagland's solution as the sole source of irrigation. Both experiments were replicated four times. For both experiments forage sorghum was seeded in pots containing 7 kg of air‐dried Amarillo fine sandy loam soil. Sorghum survivability and plant height were measured. In the second experiment, water use by sorghum was also measured. Plants were harvested 7 wk after seeding, weighed, dried at 55°C, weighed, and ground for subsequent mineral analysis. After harvest, soil salinity, pH, and in the second experiment, extractable soil elements were determined. Soil salinity increased, while soil pH decreased, with the salinity treatments. Extracted soil calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), manganese (Mn), and cadmium (Cd) increased while sulfur (S), iron (Fe), and copper (Cu) decreased, and aluminum (Al) and zinc (Zn) exhibited no change with increasing salinity. Sorghum aerial plant and root production decreased with increasing salinity. Plant Ca, strontium (Sr), Mn, and Cd levels increased with increasing salinity. In contrast, sorghum K, P, and S levels declined with increasing salinity.

ISSN:0190-4167    

DOI:10.1080/01904169909365762

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Calcium chloride (CaCl2) sprays increased calcium (Ca) concentrations in d'Anjou fruit(Pyrus communisL.), reduced the incidence of cork spot and improved shelf‐life by increasing fruit firmness in a critical year that had lower fruit Ca concentrations due to record high spring and late season temperatures. The third and final harvest in late September resulted in larger fruit size, lower fruit Ca concentrations, higher incidence of cork spot, more extractable juice and yellow fruit skin color, higher soluble solids and sucrose concentrations, but lower acidity than earlier harvested fruits. Fruit held longer in cold storage (145 days) had higher concentrations of fruit Ca, lower concentrations of carbon dioxide (CO2) and ethylene (C2H4), less fruit firmness, soluble solids and acidity, lower concentrations of sucrose, glucose and fructose, and less green color of fruit skin than short term storage (45 days). Shelf‐life of CaCl2‐sprayed fruit was improved because of higher concentrations of fruit Ca that resulted in a lower incidence of cork spot and brown core, fruit firmness was higher, levels of CO2and C2H4were lower, and soluble solids, acidity, and extractable juices were affected less for ripened fruit.

ISSN:0190-4167    

DOI:10.1080/01904169909365763

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Higher greenhouse tomato(Lycopersicon esculentumMill.) yield is obtained by using 25% of NH4‐N in solution compared to using NO3‐N as the sole nitrogen (N) source. However, blossom‐end rot (BER) may occur in tomato fruit when NH4‐N was present in nutrient solutions. High nutrient solution strengths improve tomato fruit quality, but can also increase BER. Two NH4‐N concentrations in solution (0 and 25%), and two nighttime solution strengths (NSS) (1X and 4X Steiner solution strength applied at 7 p.m.) were used to grow five indeterminate type greenhouse tomato cultivars: Caruso, Jumbo, Match, Max, and Trust. A significant interaction occurred between NH4‐N concentration and NSS factors: 0% NH4‐N and high NSS increased marketable yield and fruit:whole plant ratio, and reduced BER. In contrast, a concentration of 25% NH4‐N and high NSS reduced marketable yield and the fruit:whole plant ratio, and increased BER incidence. Max, Match, and Trust tomato cultivars produced high marketable yield and high dry weight of stem and leaves, but were susceptible to BER. Use of NH4‐N in solution reduced vegetative growth, and high NSS increased stem and leaf dry weight of the tomato plants. Fruit firmness was greater for the Max cultivar, and was unaffected by NH4‐N and NSS at the mature green, breaker, and red ripe fruit development stages. However, at the fully ripe stage, fruit firmness was higher with high NSS and with 25% NH4‐N.

ISSN:0190-4167    

DOI:10.1080/01904169909365764

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0190-4167    

DOI:10.1080/01904169909365755

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor