Top Fresh Weight Research Articles

SOIL pH AND MOISTURE EFFECTS ON VEGETABLE AMARANTH PRODUCTION

The effect of soil moisture and pH levels on the vegetative growth of amaranth were studied in the greenhouse during 1990-91. Three soil pH levels: 4.5, 5.3, and 6.4 and four soil water levels: 3, 6, 12 and 18% (w/w) comprised the treatments of the two studies. The plants grown in pH 6.4 were significantly taller and had greater leaf area than plants grown in pH 5.3 or 4.7 soil. There was a significant decrease in all above ground plant parts with each increase in soil acidity. The top fresh weight of plants grown in 5.6 and 4.7 pH soil were 27% and 73% lower, respectively, than plant grown in 6.4 pH soil. Plant grown in 3% soil water had significantly lower leaf, stem and root fresh weights than other soil water levels. There was no significant difference in the performance of plants grown in 6, 12 or 18% soil water, suggesting that amaranth plant is adapted to a wide range of soil moisture conditions.

Herbicide Tolerance of Selected Ericaceous Species

Abstract This study was conducted to determine the tolerance of seven Ericaceous species to 15 herbicide treatments. Treatment response was species dependent. Pre-M (pendimenthalin) at the 2.2 kg/ha (2 lb ai/A) rate reduced top fresh weight of mountain laurel (Kalmia latifolia), flame azalea (Rhododendron calendulaceum) and Carolina rhododendron (Rhododendron carolinianum) while the 4.5 kg/ha (41b ai/A) rate affected these 3 species plus drooping leucothoe (Leucothoe fontanesiana), sourwood (Oxydendrum arboreum), Catawba rhododendron (Rhododendron catawbiense) and azalea ‘Hinocrimson’ (Rhododendron ‘Hinocrimson’). SWGC (pendimethalin) at 3.4 kg/ha (3 lb ai/A) reduced top fresh weight of sourwood, flame azalea and Carolina rhododendron. Goal (oxyfluorfen) + AG98 reduced fresh weight of every species except Carolina rhododendron. Snapshot DF (isoxaben + oryzalin) at 3.4 kg/ha (3 lb ai/A) reduced top fresh weight of mountain laurel and flame azalea. Mountain laurel showed a reduction in fresh weight for Pennant GR (metolachlor) at the 4.5 kg/ha (4 lb ai/A) rate. At the 2.2 kg/ha (2 lb ai/A) rate of Ronstar WP (oxadiazon), reduced Catawba rhododendron top fresh weight, however, Catawba rhododendron was not affected by the 4.5 kg/ha (4 lb ai/A) rate. The Poast (sethoxydim) treatment at 0.6 kg/ha (0.5 lb ai/A) + crop oil concentrate reduced fresh weight of flame azalea. SWGC at 3.4 kg/ha (3 lb ai/A), OH2 (oxyfluorfen + pendimethalin) at 3.4 kg/ha (3.0 lb ai/A), Gallery (isoxaben) at 1.1 kg/ha (1.0 lb ail A), Snapshot GR (isoxaben + trifluralin) at 4.0 kg/ha (3.75 lb ai/A), Derby (metolachlor + simazine) at 5.7 kg/ha (5.0 lb ai/A), and the ready-to-use formulation of sethoxydim did not reduce top fresh weight of any of the seven species tested.

Soil Temperature and Copper Application Rate Affect Growth and Copper Deficiency of Aglaonema commutatum ‘Fransher’

Abstract Fransher aglaonema (Aglaonema commutatum Schott. ‘Fransher’) were used during the winter and spring in two duplicate 4 × 3 factorial randomized block design experiments with four continuous soil temperatures [13.0, 18.5, 24.0 and 29.5° ± 1°C (55, 65, 75, and 85°F ± 1.8°F)] and three copper levels [0, 0.05, and 0.1 g/15 cm pot (0, 0.0017 and 0.0035 oz/6 in pot(] from Cu Sequestrene. Plants were placed into zoned forced-air systems for soil temperature control in a glass greenhouse with an average maximum light intensity of 13 klx (1200 ft-c) and minimum and maximum air temperatures of 16 and 30°C (60 and 86°F), resp. Plant grade, color grade, number of breaks, root fresh weights, and elemental tissue content of Ca, Mg, and Cu increased linearly with increased soil temperature, while elemental tissue content of K decreased linearly with increased soil temperature. As copper application rate increased, plant grade, color grade, and elemental tissue content of Cu increased linearly and elemental tissue content of K, Ca, Mg, Mn, and B decreased linearly. Interactions of increased soil temperature and Cu application rate resulted in increased top fresh weights, elimination of Cu deficiency symptoms, and decreased leaf elemental P content.

ヤーコンの栽培に関する研究 第３報 植付け方法の相違がヤーコンの収量に及ぼす影響

Cultivation of yacon (Polymnia sonchifolia) has gradually been spreading in Japan. We experimented on the effect of planting methods on the growth and yield of yacon by using a Light-colored Andosol. Two experimental plots were made: plot A in which seed tubers were placed directly into the field soil and plot B in which seedlings were transplanted after raising them.The results were as follows.1) Growth of yacon in plot A was faster than that in plot B in the initial stage. But, at harvest, the difference of top fresh weights and dry weights were not significant in both plots.2) Since the yield of yacon tuber in plot A (46.8t/ha) was much higher than that in plot B (27.8/ha), the method placing seed tubers directly into the field soil will be more suitable to obtain maximum yield.3) Since more time was used for weed control in plot A than in plot B, investigation of the weeding system will be necessary.

POTTED GERANIUM (PELARGONIUM × HORTORUM) GROWTH WITH LEACHING FRACTIONS OF O to 0.4

Geranium `Yours Truly' in 15-cm diameter plastic pots were greenhouse-grown as single pinched plants in a completely randomized design. Plants were irrigated with 300 mg/liter N from 20N-4.4P-16.6K with leaching fractions (LF) of 0, 0.1, 0.2, and 0.4. There were 24 irrigations during the 8-week study. Plants with LF of 0.2 and 0.4 had 46% greater leaf area, 40% greater top fresh weight, and 37% greater top dry weight than plants with LF of 0 and 0.1. By week 5 the leachate electrical conductivity (EC) for LF of 0.1, 0.2, and 0.4 had increased from about 3 dS/m initially to 12, 8, and 4 dS/m, respectively. At harvest, medium ECe was 7, 4, 3, and 2 dS/m for LF of 0, 0.1, 0.2, and 0.4, respectively. At harvest, medium pH was the same in the top, middle, and bottom thirds of the pot. At harvest medium ECe with LF of 0.1, 0.2, and 0.4 was 47, 68, and 60% lower in the bottom two-thirds of the pot than in the top third. With a LF of 0 the medium ECe was not lower in the bottom of the pot. Minimizing the LF for potted geraniums substantially reduced plant growth.

Effect of nitrogen on the yield and quality of irrigated onions (Allium cepa L.) cv. Cream Gold grown on siliceous sands

The effect of nitrogen (N), at rates up to 590 kg N/ha, on the yield and quality of Cream Gold onions grown on siliceous sands was investigated in field experiments conducted during 1987-88 (1 site) and 1988-89 (2 sites). As the rate of applied N increased there was a significant (P<0.001) increase in the fresh weight of tops harvested when the largest bulbs were 25-30 mm in diameter. Fresh weight of tops was significantly (P<0.001) correlated with final marketable yield of bulbs. Nitrogen application accelerated top senescence. Nitrogen-deficient plants had erect green tops at harvest. Marketable yield was significantly (P<0.01) increased and the yield of culls (unmarketable bulbs) was significantly (P<0.01) decreased as the rate of N increased at all sites. Nitrogen rates in the range 299-358 kg N/ha were required for 95% of maximum yield. Scale thickness increased significantly (P<0.05) and glucose and fructose concentrations decreased significantly (P<0.05) at 2 sites as the rate of applied N increased. Soluble solids and dry matter of bulbs were not affected by N. Bulb size increased as the rate of applied N increased, however, the magnitude of the effect varied between sites. Number of days to 10% sprouting during storage at 15 � 0.5�C was significantly increased as the rate of applied N increased up to 40 kg N/ha at 2 sites. We have concluded that for the cv. Cream Gold grown on siliceous sands, the high rates of fertiliser N required to maximise marketable yield and bulb size were not detrimental to quality.

ヤーコンの栽培に関する研究 第２報 黒色ポリマルチとわらマルチが収量に及ぼす影響

Effect of mulching, one of the basic problem of Yacon cultivation, were investigated.Three experimental plots were designed: 1) poly-mulch plot; Black polyethylene film 0.02mm thick was mulcheyd, 2) Straw mulch plot; straw was mulched and 3) no mulch plot.The resuts obtained were as follows:1. The top fresh weight in no mulch plot was the heaviest.2. Total number of the tuberous roots increased in the poly-mulch plot, but the number of tuberous roots over 100g per root decreased.3. Total weight of tuberous roots and the total weight of tuberous roots over 100g per root increased in the straw mulch plot.4. Total numbers of creacked tuberous roots increased in the poly-mulch plot.5. Straw mulching resulted in high tuberous roots yield, but yield under black polyethlyene film mulching was poor.

培養液への光入射が培養液組成と野菜の生育に及ぼす影響

Nutrient solution in hydroponics is usually covered with the shading material, plate or film. A hydroponic vegetable production system which uses a movable vegetable supporting mechanism for varying the space among vegetables according to the growth stage, called “spacing”, was developed. For easy spacing, it is desirable not to use the shading material on the nutrient solution. Then, the nutrient solution is exposed to the light. There are a number of unclarified points concerned with the effects of the lighted nutrient solution on vegetables growth.Two experiments were performed. In experiment 1, to observe the effects on vegetables growth, spinach (Spinacia oleracea) and Senpoh-sai (Brassica×hybrida) were planted in two hydroponic beds. One bed was covered with the shading plate to keep the nutrient solution dark, and the other bed was not covered to expose the solution to the light. In experiment 2, to investigate hourly changes of the composition of the nutrient solution, the nutrient solution was illuminated with white fluorescent lamps.The top fresh weight of spinach 17 days after transplanting to the lighted nutrient solution decreased to 36% of the control. The primary cause of vegetable growth inhibition was considered to be iron deficit induced by changing of soluble iron (EDTA-Fe) into insoluble one (FePO4).94% of soluble iron in the nutrient solution under the lighting intensity of 240μmol/m2/sec changed into insoluble iron for 42 hours. When the lighting intensity in the nutrient solution is reduced to 11.8μmol/m2/sec by shading, the change of soluble iron into insoluble one is controlled at 5% increase per day compared with case of quite dark condition.These results will provide clues for studying on soluble iron condition of nutrient sterilization using ultra violet lay and tissue culture medium of a transparent vessel.

Use of chitin for controlling plant-parasitic nematodes

Cabbage plants were grown in soil amended with Clandosan (CLA) prepared from crustacean chitin (0.3% w/w). The plants were maintained in constant temperature tanks set to 15° or 30°C, in soils naturally infested with cyst nematodeHeterodera schachtii, or inoculated with the root-knot nematode,Meloidogyne javanica, respectively. At 30°C, after the first month following inoculation, CLA caused an increase in top fresh weight of plants but no reduction in nematode—induced root galling was recorded. However, when fresh plants were planted, CLA induced a large reduction in gall formation and caused an increase in top fresh weight of nematode-inoculated plants. At 15°C, CLA significantly affected the plants only after 60 days: an increase in top fresh weight and a reduction in the number of eggs per cyst were recorded. Ammonium was not detected in soil after 30 days, at 30°C, whereas at 15°C, CLA-treated soil contained twice as much ammonium as non-treated soil. After 60 days, ammonium was not detected at all. After 30 days nitrate concentrations in soil attained higher values at 30°C than at 15°C, whereas after 60 days high levels were detected only at 15°C. At 30°C, CLA induced an increase in the number of fungi, chitinolytic bacteria, and total amount of bacteria; at 15°C, such an increase was detected only with the chitinolytic microorganisms.

Determination of phytotoxic soil aluminium by electroultrafiltration

AbstractThe experiments address the questions of whether phytotoxic Al can be determined by electroultrafiltration (EUF). Spring barley (Hordeum vulgare) was grown in pot experiments on 28 soils differing widely in their characteristics. Al toxicity was measured in terms of root parameters and top growth. On soils rich in EUF extractable Al typical Al toxicity symptoms were found in roots and tops. EUF extractable Al obtained at the cathode (EUF‐Al, cathode) was correlated with root fresh weight (R2 = 0.554), root length (R2 = 0.653), root diameter (R2 = 0.729) and fresh weight of tops (R2 = 0.681). The Al obtained at the anode was not correlated with any of these plant parameters. It is supposed that this anionic Al consists of non toxic organic Al complexes. Correlations between plant parameters and KCl‐exchangeable Al were less close than those for EUF‐Al (cathode). Correlations between soil pH and plant parameters were in between the correlations for exchangeable Al and EUF‐Al (cathode).

Evaluation of a protein-chitin derivative of crustacean shells as a slow-release nitrogen fertilizer on Chinese cabbage

SummaryA commercial product with nematicidal properties, derived from crustacean shells, is of interest as a fertilizer. The purpose of this study was to establish the potential of this organic natural compound as a slow-release nitrogen fertilizer. Chinese cabbage seedlings grown in sandy loam soil at root temperatures of 15,20,30, and 35°C were fertilized weekly with a commercial 4-2-8 liquid fertilizer (mineral-treated plants) or with one of two organic nitrogen sources: Clandosan (CLA), or the slow-release compound urea-formaldehyde (UF). Ammonium (NH4+) was the major product accumulated in the soil 14 days after planting in both CLA and UF, mainly at the higher temperatures. Thirty days after planting, NH4+ in soil was not detected in the different treatments, except for UF at 15°C. Nitrate (NO3−) was found in the soil only at very low concentrations. Almost no differences in top fresh weights (TFW) were observed after 14 days. However, after 30 days, CLA- and UF-fed plants had higher TFW than minera...

Salinity effects on four arid zone plants

Kochia prostrata L., Kochia brevifolia R. Br., Parthenium argentatum A. Gray, and Simmondsia chinensis (Link) C. K. Schneid., were tested to determine the effect of soil salinity on growth and yield. P. argentatum was tested in salinized field plots, while the other three species were tested in salinized soil cultures in the greenhouse. The salinity level at which an initial yield decline occurred (the threshold) for K. prostrata and K. brevifolia was 2·3 and 1·3 dS/m (electrical conductivity of the saturation extract: (κe)), respectively. The reduction in yield for each unit increase in salinity above the threshold was at 2·1 per cent for K. prostrata and 2·4 per cent for K. brevifolia. Soil salinities greater than 6·1 dS/m (the threshold) significiantly reduced fresh top weights of P. argentatum. Rubber concentration significantly increased with increased soil salinities up to 13·2 dS/m. S. chinensis exhibited no effects from salinity during the first year of development. During the second year, both stem diameter and flower counts were significantly reduced at a soil salinity of 14 dS/m. S. chinensis and K. prostrata effects have been previously reported, while the data for P. argentatum and K. brevifolia are from current projects.

Effect of Soil Moisture Tension and Soil Water Content on the Growth of Chrysanthemum in 3 Container Media

Abstract No differences in final height, top fresh weight, top dry weight, or flower number were observed in Chrysanthemum morifolium Ramat. ‘Spice’ grown in 16.5-cm azalea pots when allowed to dry to soil moisture tensions of 5, 10, 20, or 30 kPa between waterings. Differences did occur in these parameters among the 3 tested media. Differences also occurred across all 3 media based on the volume of water remaining in the pot prior to watering. Plants growing in media containing more than 500 ml water just prior to irrigation had increased growth compared to plants in media containing less than 500 ml water. Cubic regression models were used to describe the percentage of moisture in the pot at soil moisture tensions between 0 and 30 kPa. The model may be used to predict container capacity and air space for most container sizes.

環境変化によるリーフレタス地上部生体重量の短期的変化

Top fresh weight of leaf bunching lettuces (Lactuca sativa L. cv. ‘Grand rapids’) in hydroponics were continuously measured under the conditions changing in relative humidity, air temperature and light intensity.Reversible fluctuations of top fresh weight were observed. The fluctuations started immediately after the changes in environment, and continued within 30 minutes after the changes. Light and air temperature were more effective on the fluctuation than relative humidity.The fluctuations were distinguished from long-term changes in fresh weight by its reversibility. The transpiration rate showed opposite pattern of the fluctuation caused by environmental change.These results suggest that short-term fluctuations reflect the balance of input and output of water which may be regulated by transpiration.

Aplicador de herbicidas com pavios de corda: primeiros resultados de controle

Os aplicadores de herbicidas baseados em pavios de corda foram introducidos e largamente aceitos nos EUA a partir de 1978, devido a sua grande simplicidade, baixo custo operacional e economia do herbicida. Um protótipo fabricado com material inteiramente nacional, montado sobre duas rodas de bicicleta, tracionado pelo homem, tendo uma barra de 2 metros de comprimento, foi desenvolvido pelo departamento de defesa fitossanitária da Faculdade de Ciência Agrárias e Veterinárias de Jaboticabal - UNESP e submetido a um ensaio preliminar. A área estava uniformemente coberta com vegetação natural, com altura média de 55 cm e a maioria das plantas daninhas em estádio de maturação das sementes. O aplicador foi deslocado à velocidade de 2,7 km/h, com consumo médio de 9,3 litros de calda por hectare, tendo aplicado diluições de glyphosate em água, nas proporções de 1:2, 1:4 e 1:6 (produto comercial: água) e comparado à pulverização convencional tratorizada, efetuada com velocidade de 4,2 km/h e consumo de 4 litros de produto comercial com 310 litros de água por hectare. As avaliações do controle foram efetuadas através da determinação da biomassa epígea por ocasião de aplicação aos 15 e 33 dias após , além da atribuição de notas aos 33 dias da aplicação. Os resultados mostraram-se promissores para o protótipo, que pode desde já ser considerado um precioso instrumento para o manejo de plantas daninhas.

Sulfur supply and the formation of vesicular-arbuscular mycorrhizas by Glomus fasciculatum on subterranean clover

Sulfur supply and the formation of vesicular-arbuscular mycorrhizas by Glomus fasciculatum on subterranean clover

Effect of nitrogen form at various levels of potassium, on the Meloidogyne-Fusarium wilt complex in muskmelon

The influence of various potassium concentration and of nitrate or ammonium was evaluated on non inoculated muskmelon plants and on plants inoculated with theFusarium wilt pathogen (F), the root-knot nematode (Meloidogyne javanica) (Nem), or a combination of both pathogens (F+Nem). Increasing potassium concentrations raised top fresh weights (TFW) in all four groups. Nitrate fertilized plants weighed more than plants receiving ammonium, independent of the K+ level in the medium. In the Nem+F infected plants TFW values were one and half to two times greater in those receiving the nitrate than in those receiving the ammonium. Number of nematodes in the roots were not affected by nutritional difference. In the ammonium fertilized F and Nem+F plants 30% more wilting was found than after nitrate application. Irrespective of the form of nitrogen that was applied accumulation of N, P and K was found in the roots of the Nem+F and/or Nem plants, while in the shoots Ca, Mg, Na and P accumulated and K was depleted.

Carbofuran Affects Growth and Ectomycorrhizal Development of Loblolly Pine Seedlings

Abstract Soil-incorporated carbofuran (Furadan®) at 0.44 g active ingredient (AI) per seedling reduced ectomycorrhizal development by Pisolithus tinctorius and growth of 1-0 loblolly pine (Pinus taeda L.) seedlings after five months in a greenhouse test. Seedlings with P. tinctorius ectomycorrhizae and without carbofuran were significantly taller and had greater top, root, and total fresh weights than those with any other insecticide-symbiont combination. Ectomycorrhizal development by Thelephora terrestris was not significantly affected by carbofuran. Carbofuran, especially at 0.22 or 0.44 g AI per seedling, reduced seedling growth regardless of ectomycorrhizal status. Results of this greenhouse test suggest a biological interaction between carbofuran and ectomycorrhizal fungi; additional studies are needed to determine if this effect also occurs under field conditions. However, the use of this insecticide to control the Nantucket pine tip moth or the pales and the pitch-eating weevils in outplantings has the biological potential to decrease the benefits of specific ectomycorrhizae to the survival and growth of loblolly pine.

Effect of cultivar, sowing date, and harvest date on yields and sugar contents of beet on a dry land site in Canterbury

Abstract Vytomo sugar beet and Yellow Daeno and Monoblanc fodder beets were sown on 23 September, 19 October, and 23 November 1979, and harvested at 4-weekly intervals from December 1979 to September 1980. The September sowing gave higher sugar yields than the October sowing, until April. The November sowing gave sugar yields about 2.5 t/ha less than the October sowing for all harvest dates. Sugar yields increased until July, initially because of increases in root fresh-weight and, to a lesser extent, root dry matter (DM)%. However, after May, increases mainly resulted from higher sugar content of root DM. Sugar in the roots was practically all sucrose until the September harvest, when total sugar yields fell but the proportion of reducing sugars increased. Monoblanc fodder beet gave the highest sugar yields, particularly later in the season. Top fresh-weights declined throughout the autumn and winter, but increased again in late August-September. Maximum leaf area indices (LAI) were low, and were achieve...

Photoperiod and Temperature Effects on NonStop Tuberous Begonias1

Abstract Extended long days or interrupted night photoperiods increased leaf number and top fresh weight, and decreased tuber formation compared with short days with 2 cultivars of the “NonStop” series of tuberous begonia (Begonia X tuberhybrida Voss). Short days increased tuber size and fresh weight and reduced top fresh weight of both cultivars. ‘Double Red’ showed greater leaf number, top fresh weight, tuber fresh weight, and tuber size at 22°C than at 26°, while ‘Double Orange’ showed only greater top fresh weight at 22°. Flowering was enhanced in both cultivars under long days.