Average Berry Weight Research Articles

181 Strawberry Growth and Weed Control in Response to Using Corn Gluten Hydrolysate

Alternative approaches to strawberry production that rely on cultural practices, biological controls, or natural products to reduce or replace off-farm chemical inputs are needed. Driving this growing interest are environmental concerns and rising production costs. Corn gluten meal (CGM), a byproduct of corn wet-milling, has weed-control properties and is a N source. The weed control properties of CGM have been identified in previous studies. The hydrolysate is a water-soluble, concentrated extract of CGM that contains between 10% to 14% N. Our objective was to investigate corn gluten hydrolysate as a weed control product and N source in `Jewel' strawberry production. The field experiment was a randomized complete block with a factorial arrangement of treatments and four replications. Treatments included application of granular CGM, CGM hydrolysate, urea, urea, and DCPA (Dacthal), and a control (no application). Granular CGM and urea were incorporated into the soil at a depth of 2.5 cm at rates of 0, 29, 59, and 88 g N/plot. Plot size was 1 × 3 m. The field experiment was conducted from 1995-1998. The source of nitrogen showed few effects for all variables measuring yield and weed control for all years. In general, the rate of nitrogen had little or no effect on total yield. However, the rate of nitrogen at 88 g N/plot showed an increase in average berry weight, leaf area, leaf dry weight, and weed control.

Effect of Nitrogen Levels on Fruit Firmness and Plant Response of Hydroponicall y Grow n `Chandler ' Strawberries

`Chandler' strawberry plants were established in a recirculating nutrient flow hydroponic system under six nutrient solution N levels (35, 70, 140, 210, 280, and 350 ppm). Various morphological and fruiting responses were measured. Average berry weight was greatest in the 280 ppm range and lowest in the 350 ppm solution N treatments. Percent soluble solids were greatest in the 35 ppm and lowest in the 140 ppm N treatments. Titratable acidity was greatest in the 75 and 210 ppm treatments and lowest in the 140, 280, and 350 ppm N treatments. Nitrate N was greatest in the juice of the 280 and 350 and lowest in the 35 ppm N treatment. Interior and exterior fruit firmness followed a general trend of the greatest firmness being found at 35 ppm and the least firm berries being from the 350 ppm treatment.

Impact of Taedia scrupeus (Hemiptera: Miridae) Feeding on Cluster Development in Concord Grapes

Taedia scrupeus (Say) feeds on grape clusters and shoots early in the growing season. The impact of nymphal and adult feeding was assessed at the individual shoot level by confining nymphs within sleeve cages at 4 different times: prebloom, bloom, postbloom, and prebloom to postbloom. Prebloom feeding significantly reduced the number of berries per cluster and average berry weight, resulting in a 68% reduction in cluster weight. When nymphs were allowed to feed from prebloom to postbloom, cluster weight was reduced by 71%.Feeding only during bloom and postbloom did not affect cluster weight. Prebloom feeding reduced the number of florets per cluster, berries per cluster, and berry weight. The whole-vine impact of T. scrupeus was examined in a commercial Concord vineyard, where 3-vine experimental units were treated with carbaryl to remove T Scrupeus or were left untreated. Unsprayed vines, with a mean density of 20 T. scrupeus per vine, yielded 10.4 kg per vine, and sprayed vines without injury yielded 14.1 kg per vine. The yield component most strongly affected was the number of clusters per vine, which averaged 165.4 and 131.8 per vine in sprayed and unsprayed vines, respectively. Each T. scrupeus nymph was associated with 0.18kg of crop loss, suggesting that as few as 0.5 nymphs per vine can cause economic injury. Where treatment of vineyards to prevent T. scrupeus injury is warranted, it must be applied during the prebloom period.

The effect of thermal environment, planting date and crown size on growth, development and yield of Fragaria × ananassa Duch. cv. Elsanta

SummaryThe effects of environmental conditions, planting date and crown size on the timing, intensity and duration of cropping in the strawberry Fragaria × ananassa cv. Elsanta were investigated. Temperature was positively correlated with the rate of progress to fruiting whereas crown size had no effect. The first fruit reached harvest maturity after an estimated 891 day-degrees had elapsed above a base temperature of 2.9°C for waiting bed plants and 831 day-degrees above a base temperature of 2.4°C for cold stored plants. Temperature was negatively correlated with total yield, berry number and average berry weight for both waiting bed and cold stored plants of different crown sizes. Yield, berry number and average berry weight were positively correlated with crown size. The effect of temperature on the yield components appeared to be due to its effect on vegetative growth of the plants: canopy development was more limited at warmer temperatures. These results can be used to generate models to predict the effect of growth environment on cropping in strawberry.

Effect of N Fertilization on `Arapaho' Thornless Blackberry

Applications of N to blackberry plantings are a common practice in Arkansas, but fertilizer recommendations are largely based on those of other states. The need for information on fertility of a new blackberry from the Arkansas breeding program motivated this study. A three-year-old `Arapaho' blackberry planting at the University of Arkansas Fruit Substation was used for this study. Treatments which began in 1994 and continued through 1996 were: 1) control—no N applied, 2) 56 Kg N/ha applied in a single application in early spring, 3) 112 Kg N/ha applied in a single early spring application, and 4) 112 Kg/ha applied in a split application with one-half applied in the early spring and one-half applied immediately after harvest. Fruit was harvested from the plots in June and total yield and average berry weight determined. Foliar samples were collected in August and elemental analysis conducted. Primocanes in each plot were counted at the end of the growing season. Over the three years, there was no significant treatment effect on yield, berry weight, or primocane number. A trend toward higher primocane number where N was applied was seen, however. Foliar levels of N, P, K, Ca, S, and Mn were affected by either N rate or time of application. The foliar N levels were influenced by N rate and the split application gave the highest concentration. Calcium was higher when no N was applied, Mn was greater at higher N rates while the control had the lowest foliar N level in each year.

The Effect of Nitrogen Fertilizer Rates and Timing on Cranberry Yield and Fruit Quality

To examine the impact of N fertilizer rates and timing on cranberry (Vaccinium macrocarpon Ait.) yield and the fruit quality factors total anthocyanin, average berry weight, and field and storage rot, plots were established for 3 to 4 years. The cranberries received a total of 0, 22, or 44 kg N/ha over the growing season applied in three, four, or five applications, which varied by growth stage. There were eleven possible treatment combinations in Massachusetts on `Early Black' and `Howes' and in Wisconsin on `Stevens' and `Searles', and seven possible treatments in New Jersey on `Early Black' and in Washington on `McFarlin'. The results showed a nationwide response to N that suggests the experimental middle rate of 22 kg·ha-1 would result in high yields with moderate rot. However, the best timing for applying the fertilizer varied by both state and cultivar, where three late season applications were best on `Early Black' in New Jersey versus four early season applications on the same cultivar in Massachusetts, and applying N fertilizers across five applications was optimal for `Stevens' in Wisconsin.

Yield, Growth, and Weed Control in Four Strawberry Production Systems

Field plots of four production systems of `Tristar' dayneutral and `Earliglow' June-bearing strawberry (Fragaria ×ananassa Duch.), established in 1993, included conventional practices (CONV), integrated crop management practices (ICM), organic practices using granulated corn gluten meal, a natural weed control product, (ORG-CGM), and organic practices using a natural turkey manure product (ORG-TM). `Earliglow' total yield from CONV plots in 1994 was similar to ICM and ORG-CGM, but greater than ORG-TM. Average berry weight and marketable yield were greater in the CONV system than both organic systems. CONV, ICM, and ORG-CGM plots had more runners and daughter plants than ORG-TM. Plots with CONV herbicide treatments were similar to ICM and ORG-CGM for percentage weed cover 1 month after renovation. `Tristar' crown number, crown and root dry weights, yield, and berry number were reduced when plants were grown under straw mulch in ORG-CGM and ORG-TM compared to CONV and ICM plots with polyethylene mulch.

Cranberry tissue nutrient levels as impacted by three levels of nitrogen fertilizer and their relationship to fruit yield and quality

Abstract Five different cranberry (Vaccinium macrocarpon Ait.) cultivars were fertilized with either 0, 22, or 44 kg N ha/yr. After three consecutive years of these treatments, plant tissue samples were taken and analyzed for the elements, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), boron (B), iron (Fe), copper (Cu), and zinc (Zn). These were compared to N dose and to fruit quality and quantity parameters. Across all cultivars, tissue N, P, and K levels increased with increasing N dose, whereas Fe tended to decrease with increasing N dose. Only the element Mn showed no relationship to N dose for any cultivar. Tissue N concentration was generally unrelated to fruit yield. However, fruit rot (both field and storage) was strongly related to tissue N. Average berry weight was related to the tissue concentration of a number of elements. This research suggests that tissue nutrient concentration may be useful in predicting rot and fruit size potential in cranberries.

LEAF REMOVAL INFLUENCES CANOPY STRUCTURE, BUNCH ROT AND YIELD WITH VITIS VINIFERA L. CVS. OPTIMA AND CABERNET FRANC.

Leaf removal treatments were applied to Vitis vinifera L. cvs. Optima and Cabernet Franc in the Canadian Niagara Region in 1992. Treatments consisted of removing 0% (no leaves), 50% (every other leaf) and 100% (all leaves) from the shoot origin to the most distal cluster when berries were pea-sized. Data was collected on canopy structure, occurrence of bunch rot (Botrytis cinerea Pers.:Fr.), yield, must and wine quality. Application of the 50% and 100% leaf removal (LR) treatments reduced leaf layer number (LLN), percent interior leaves (PIL) and percent interior clusters (PIC) with both cultivars. The influence of LR on LLN, PIL and PIC was greatest for the 100% treatment compared to 50% and 0% This resulted in a reduction in the severity of bunch rot with Optima and a reduction in the incidence and severity with the disease tolerant cultivar Cabernet Franc. The 50% and 100% LR reduced yield per vine by 33% and 46% respectively with Optima and by 32% and 29% respectively with Cabernet Franc. Average berry weight of the 50% and 100% treatments was significantly lower for Cabernet Franc. Within both cultivars, there was no significant effect of treatment on the number of clusters and number of berries per cluster. Significant influence of the treatments on the must and wine quality was also noted.

CRANBERRY VARIETY FRUIT YIELD AND YIELD COMPONENETS

Accurate estimates of yield and yield components for parental selection would facilitate cranberry breeding efforts. A study was designed to obtain value estimates for traits related to yield. Ten commonly-cultivated varieties grown in a replicated planting, were evaluated in 1991 and 1992 for fruit yield per unit area (FY), average berry weight (BW) and number of berries per unit area, or berry concentration (BC). Averaged over all varieties, FY was significantly greater in 1992. BC was responsible for higher yields in 1992. Regression analysis revealed that BC accounted for more of the variation in FY than did BW in both years. BW accounted for some variation, however, in 1991 when FY was lower. Varieties differed significantly in FY, BW and BC. Hybrid varieties bad significantly greater FY and BW than wild selections. Variation for yield components exists among varieties tested, suggesting genetic gain is possible for yield with additional breeding efforts. In particular, greater fruit set should be emphasized as a breeding objective.

BLOOM APPLICATIONS OF GIBBERELLIC ACID INCREASE FRUIT SET AND YIELD OF RABBITEYE BLUEBERRIES IN FLORIDA

Six-year-old, field-grown `Beckyblue' and `Bonita' rabbiteye blueberries were sprayed to drip with Pro-Gibb (250 ppm GA3, 0.1% surfactant, pH 3.1). Two spray applications were made. The first spray was applied at 80-90% full bloom followed by a second spray 10 days later. Fruit were harvested at five dates, from 21 May until 1 July, 1992. GA3 increased fruit set and doubled total fruit yield for both cultivars compared to the control. Fruit yield was greater for the GA3 treatment than for the control at harvest dates 3 through 5 for 'Beckyblue', and dates 4 and 5 for 'Bonita'. Average berry weight for both cultivars and for both treatments declined as the season progressed. For `Beckyblue', average berry weight did not differ between treatments at most harvest dates. For 'Bonita', average berryweight was less for the GA3 treatment than for the control at harvest dates 3 through 5. GA3 increased yield of rabbiteye blueberry with little detrimental effect on fruit size. However, results from Georgia suggest that greater positive effects on fruit set should be possible.

HARVEST AGE EFFECT ON YIELD OF ERECT BLACKBERRIES

Yield and average berry weight were measured for first year fruiting (on semi-erect canes) and second year fruiting (erect canes) to compare harvest age effect for erect blackberries established from root cuttings. cultivars were `Cheyenne', `Choctaw', `Navaho' and `Shawnee' and 4 plantings were included in the comparison. One of the four plantings had an average yield of 27% more in the first year as compared to the second year. The other plantings had higher yields in the second year as compared to the first ranging up to a 100% increase. Yield was 23% higher for the second year when all plantings were averaged. Average yield increase by cultivar in the second year compared to the first was: 'Choctaw' 37%, 'Cheyenne' 27%, 'Navaho' 22% and 'Shawnee' 20%. Berry weight was not affected by harvest age except in one planting, where average weight was higher for first year fruiting.

IMPROVED DOWNY MILDEW CONTROL IN WINE GRAPES WITH VOSSEN BLUE

Downy Mildew, Plasmopara viticola, causes major damage and economic loss to many wine grape cultivars grown in the Northeast. The purpose of the experiment was to test the efficacy of Vossen Blue (VB; iron pigment) in association with fungicides for the control of Downy Mildew disease of wine grapes in New Jersey. The experimental plot was a planting of `Seyval Blanc' (5th leaf). Treatments (applied via back-pack sprayer) included no fungicide (control I), full fungicide (FF) (RCE commercial recs; control II), FF + 4%VB, FF + 8%VB, 8%VB, Half Rate Fungicide (HF) + 4%VB, HF + 8%VB. There were no significant differences between treatments for total yield, average cluster weight, average berry weight, Brix %, and pH. Spectrophotometric (Hunter's Lab) analysis of foliage samples revealed that leaf samples from the VB treatments had greater green color (correlate: increased chlorophyll). Analysis of subjective (1-9) disease incidence data: FF8 significantly lower disease score that FF; FF4, HF4, HF8, and FF no difference. Compared to normal full fungicide: superior Downy Mildew control was achieved by adding VB to full fungicide; equal control was achieved with half fungicide and VB.

Growth and Fruiting of Container-Grown Seyval blanc Grapevines Modified by Changes in Crop Level, Leaf Number and Position, and Light Exposure

Container-grown Seyval blanc grapevines were subjected to varying crop and leaf levels. In adjusting leaf number, approximately 8 to 10 cm² leaf area per gram of fruit weight gave maximum total fruit weight, average berry weight, and °Brix. Leaf, stem, and root dry weights increased through 15 cm²/g, the maximum leaf area/ fruit weight measured. Titratable acidity (TA) and pH were not consistently changed. A reduction in leaf area affected vegetative growth first, °Brix next, and fruit weight last. In modifying leaf position in relation to a basal cluster, total fruit weight, °Brix, TA, pH, and vegetative growth were highest on plants with leaves distal to the clusters. These results were likely due to good exposure and greater area of leaves on these distal nodes. Regrowth from an apical node advanced fruit maturity and increased vegetative growth rather than compete with it. Shading lower leaves and the cluster (versus removing lower leaves) did not affect total fruit and average berry weights. Root dry weight was greater where leaves were shaded.

Soil pH effects on yield and fruit size of two rabbiteye blueberry cultivars

The effects of soil pH on yield and average berry weight of rabbiteye blueberry cvs Delite and Tifblue were investigated. Over a three year period, the higher soil pH decreased from 6.5 to 5.9, but the total yield of both cultivars decreased more than 60% as soil pH increased from 4.5 to 6.5 in the first two years and to 5.9 during the last year. Percent marketable yield was less influenced by the change in soil pH than was total yield. ‘Tifblue’ produced more fruit and had higher marketable yields, but the fruit size determined by average berry weight was smaller than ‘Delite’. When the soil pH was at a more desirable range for maximum yield (4.5 to 5.3), ripening was more uniform for both cultivars. This study illustrated that: (a) two rabbiteye blueberry cultivars differed in tolerance to alkaline growing conditions, (b) the response of the two cultivars to the change in soil pH varied from year to year, and (c) total yield of both cultivars was maximized when soil pH was below 5.0.

Effect of irrigation on yield, berry weight, and sugar content of blackcurrants

Abstract Blackcurrant bushes (cv. Magnus) planted on a free-draining Lismore stony silt loam were used to study the yield responses to four irrigation regimes, using one unirrigated and three irrigated treatments. Irrigation treatments were applied each time gravimetric soil samples (0–150 mm deep) taken 300mm from the hedgerow fell to 10,15,or20%soil moisture (s.m.) content. In the first two years, the 15 and 20% s.m. treatments produced yields 150-220% higher than both the unirrigated and infrequently irrigated 10% s.m. treatments. As the unirrigated and 10% s.m. treatment bushes developed with time, the annual yield differences decreased to a level where, by the fifth harvest, the 15 and 20% s.m. treatment yields respectively were only 15% and 37% higher than the unirrigated treatment yield. Average berry weight increased with irrigation frequency during the first three seasons. However, differences in berry weight decreased gradually with timeandby the 1986/87 season showed no significant differences ...

Self Incompatibility in 19 Native Blueberry Selections

Abstract Nineteen native blueberry (Vaccinium ashei Reade) clones selected from several areas in northern Florida and southeastern Georgia were self- and cross-pollinated in a greenhouse. Fruit set for the 19 clones averaged 15% after self-pollination and 58% after cross-pollination. Viable seeds per berry averaged four for self-pollination and 11 for cross-pollination. Average berry weight was 0.7 g for self-pollination and 1.1 g for cross-pollination, and average interval from flowering to ripening was 106 days for selfing and 92 days for crossing. Following self-pollination, pollen germinated and pollen tubes grew down the style as rapidly as after cross-pollination.

Management of cardiac arrest in the community: a survey of resuscitation services.

A survey of the English health regions identified nine ambulance based resuscitation schemes. Their structure and function are heterogeneous and their impact on patient survival is often speculative. There is considerable medical, paramedical, and lay enthusiasm for resuscitation schemes but this cannot be harnessed until medicolegal uncertainties are removed and guidelines for development are set out. Better documentation of the benefits of existing schemes should be undertaken so that advanced training of ambulance personnel can proceed rationally.

GENETIC, PHENOTYPIC AND ENVIRONMENTAL CORRELATIONS AMONG 28 FRUIT AND PLANT CHARACTERS IN THE CULTIVATED STRAWBERRY

Generic, phenorypic and environmental correlations and coheritabibties between 28 fruit and plant characters were estimated in 64 progenies produced among 31 North American strawberry clones and 1 German one under the crossing scheme similar to North Carolina Design II. Total berry and total marketable yields were positively and significantly correlated with average berry weight, berries per flower stalk, yield per flower stalk, leaf area, and petiole diameter, but negatively correlated with stolon number and flower stalk number. The inverse relationships between flower stalk number with average berry weight, and with berries per flower stalk may be genetically dependent or arise from developmentally induced relationships. Plant height appeared to be a good indicator of both early and early marketable yields; petiole number was considered the best indicator of soluble solids and easy capping, while soluble solids may be of value as an indicator of both late and late marketable yields. In general, no genetic barrier was detected to combine high yield with good quality of the berry.

HERITABILITY AND GENETIC VARIANCE COMPONENTS FOR 20 FRUIT AND PLANT CHARACTERS IN THE CULTIVATED STRAWRERRY

Heritability and genetic variance components for 20 fruit and plant characters were investigated in 64 progenies produced among 31 North American and 1 German strawberry clone under the crossing scheme similar to North Carolina Design II (Comstock and Robinson, 1952). The data were analyzed based on the assumption of random and/or mixed models of the parents. The estimation of the genetic variance components indicated that for more than half the 20 characters nonadditive variance (dominance + epistasis) constituted approximately 50% or more of the total genetic variance and that in most cases epistasis played an important role in the nonadditive variance. Heritability estimates were low (less than 18%) for total berry yield and some fruit quality characters such as firmness, easy capping, pH value, soluble solids, and external and internal appearances but were high (more than 37%) for a number of yield component characters such as average berry weight, berries/flower stalk, yield/flower stalk and flower stalk number, suggesting that substantial improvement in total berry yield could be achieved through selection on these yield components or a linear function of them.