Search Results

You are looking at 1 - 10 of 2,659 items for :

Clear All

-methylcyclopropene; CMNP = 5-chloro-3-methyl-4-nitro-1 H -pyrazole. Expt. 2: Leaf area index, yield, and return bloom in whole tree canopies sprayed with abscission agents. Leaf loss in whole canopies after abscission agent applications 6 and 28 DAB in 2007 was

Free access

altered fruit quality ( Gonçalves et al., 2011 ; Hartung et al., 1994 ; Hutchins, 1933 ). There are crops for which yield loss in the presence and absence of X. fastidiosa has been compared. In almond [ Prunus dulcis (Mill.) D.A. Webb] in California

Free access

hand harvest for all three yields. Fruit damage and yield loss. In both years immediately after harvest, the filled grape boxes were placed in ambient storage conditions; in 2014 fruit was stored in a farm shed that was noninsulated but freeze protected

Full access

Severity of rust (Uromyces appendiculatus) and yield of dry edible beans (Phaseolus vulgaris L.) were recorded for 9 years in west-central Nebraska in fungicidal efficacy trials. A weighted analysis of covariance was used to estimate yield loss due to rust. The model fit the data well (R2 =0.94), and the slope over all years had a 19 kg.ha−1 decrease in yield for each 1% increase in severity of rust. Yield response within years occurred only through reduction of rust for most fungicide treatments.

Full access

Using USLE standard plots, on 10% slope, on uniform Lowell silt loam soil, the influence of three soil treatments and two representative vegetable crops on soil runoff losses was determined. Yields (1990 and 1991) for each crop × soil treatment combination were also determined. Soil losses were determined by catching runoff, filtering, air drying and massing representative samples. With total volume per plot known, grams sediment per liter runoff were converted to kg/ha. Overall mean yields of pepper were 2.9, 4.7, and 3.7 and pumpkin were 47.3, 87.1 and 76.1 kg/7.3-m row, respectively. Mean sediment losses over five rainfall events in 1991 in peppers were 52, 1158, and 5362; and in pumpkins were 72, 3011, and 7271 kg/ha, for fescue, plastic and no-mulch treatments, respectively. Clearly, fescue in .6-m strips between rows, with comparable yields demonstrated (1991) and negligible sediment losses, was the best management practice (BMP).

Free access

Butternut squash (Cucurbita moschata) plants are susceptible to defoliation and plant population (stand) reduction by insect, disease, temperature extremes, water, hail, or other mechanical damage. The timing of such losses may have variable effects on final fruit quality and yield. The objectives of these studies were 1) to determine the influence of the degree and timing of defoliation and stand reduction on the marketable yield of winter squash; 2) to determine yield compensation after stand reduction and defoliation; and 3) to explore effects of defoliation on fruit total carotenoid content. Experiments were conducted over 2 years in New York and Pennsylvania to explore these objectives. Marketable yields consistently improved with increasing plant population. If population losses occurred while plants were in the rapid vegetative growth phase, the remaining plants responded by increasing fruit number and weight per plant. Plant losses later in the season during fruit enlargement, however, did not elicit the same magnitude of response. Defoliation of 66% leaf area reduced marketable yields, and effects were most severe under high plant populations. Competition among plants restricted compensation. Moderate defoliation (33%) reduced yield in only one of three studies. This level of defoliation also increased the percentage of medium [1.0 to 1.5 kg (2.20 to 3.31 lb)] and large [1.5 to 2.0 kg (4.41 lb)] fruit and decreased the number of jumbo fruit (>2.0 kg). Total carotenoid concentration in mature fruit was unaffected by the defoliation or population treatments. Thus, butternut squash compensated for up to 33% leaf area loss at any time during the season. While the crop could compensate, under some conditions, for up to 50% plant losses, final plant population was more important than the growth stage of damage or defoliation for effects on crop yield.

Full access

We compared soil quality, crop growth, and the incidence of pests in snapbean (Phaseolus vulgaris L.) planted in conventional tillage, in rye (Secale cereale L.) mulch without strips and in strip-tilled rye mulch. On average, yield loss was 63% in rye mulch without strips and 20% in rye mulch with strips compared to yields in conventional tillage. Soil bulk density was higher in the rye mulch treatments than in the conventionally tilled plots and may have reduced plant growth. Leaf nitrogen content was lower in the rye mulch treatments 3 weeks after planting; this may be related to nitrogen tie-up during rye decomposition or to the negative impact of soil compaction on the soil nitrogen cycle. Insect damage to snapbean pods and leaves was not affected by rye mulching. Potato leafhopper [Empoasca fabae (Harris)] populations were significantly higher for conventional tillage than for rye treatments. The incidence of white mold [Sclerotina sclerotiorum (Lib.) deBary] was reduced by the rye treatments in 1997. Further studies are needed to determine optimal strip width and develop better techniques for creating strips.

Full access
Author:

Abstract

‘Georgia Red’ sweet potato [Ipomoea batatas (L.) Lam.] plants were stored for 1, 2, and 3 weeks at 5°, 16°, and 27°C temperatures with and without bagging in perforated polyethylene. Storage conditions affected weight loss during all storage periods, but there was little difference in survival of transplants or root yield from plants stored for 1 week compared with nonstored plants. Storage at 5° for longer than 1 week was unsatisfactory because of rapid decline in field survival and root yield. Storage at 16° was superior to storage at 27°, and at 27° bagged plants were superior to bare root plants for enhancing survival and yield when plants were stored for more than one week before transplanting.

Open Access
Author:

Paprika pepper (Capsicum annuum L.) plants were subjected to a single destructive harvest in either October, November, or December to determine an optimal month for once-over harvest. Studies were conducted at two locations in Oklahoma each year for two years. Total and marketable fruit yields were highest with October harvest dates in three of the four experiments. Marketable fruit red color intensity decreased between the November and December harvest dates at both locations in the second year. It appears that paprika harvest should be completed during October in this region.

Free access
Author:

Paprika pepper (Capsicum annuum L.) plants were subjected to a single, destructive harvest in either October, November, or December to determine an optimal month for once-over harvest. Studies were conducted at two locations in Oklahoma each year for 2 years. Total and marketable fruit yields were highest with October harvest dates in three of the four experiments. Marketable fruit red pigment intensity decreased between the November and December harvest dates at both locations in the second year. When the crop is established by transplanting, paprika harvest should be completed during October in the southwestern United States.

Free access