assessing potato CNS. The detailed information of this review can be found in Goffart and Olivier (2004) , Goffart et al. (2005 , 2008) , and Olivier et al. (2006) . Presentation of a DSS for N fertilization management of potato crops The development of
, CO)]. Before preplanting fertilization, K concentration in the soil was low to medium (88 and 90 kg·ha −1 K in 2012–13 and 2013–14, respectively). Onion seedlings ‘Yellow Granex PRR’ were grown at the Vidalia Onion and Vegetable Research Center
for plants fertilized by fertigation. Bryla and Machado (2011) compared fertigation to granular applications of N fertilizer in a new planting of highbush blueberry and determined that fertigation was less efficient (i.e., less plant growth per unit
The effects of varying rates of a complete fertilizer and irrigation on the growth and fruit yields of `Tifblue' rabbiteye blueberries (Vaccinium ashei Reade) established 3 years before treatment initiation were determined in a field study. Increased rates of irrigation resulted in increased plant growth and fruit yields. Five- and 6-year-old plants were more responsive to increasing irrigation rates than older plants. Irrigation water efficacy was greatest at lower rates and progressively less at higher rates of irrigation. Five- and 6-year-old plants fertilized with the lowest rate (14N–4P–7K; 150 g/plant) grew and yielded less than those fertilized with higher rates. Older plants did not respond to fertilization rates higher than 150 g/plant. Yearly rates of fertilization above 300 g/plant did not influence plant growth or fruit yields. Fertilization and irrigation responses were independent.
practices may influence overall fruit quality and polyphenolic compound concentrations in fruits. Overall fruit quality, distribution and composition of phenolic phytochemicals are affected by maturity, cultivars, horticultural practices, fertilization
their efficacy as substrates for subirrigated crops. This project compares a range of locally available peat substitutes for greenhouse production of chrysanthemum fertilized at two N rates using conventional overhead irrigation and a capillary mat
Abstract
Fertilizer is the 2nd largest supply item purchased by commercial nurseries (1). The cost of fertilizer and labor for application has been estimated as 11% of production costs for a container nursery (2). Although fertilization (fertilizer and labor) costs are a small part of production costs, they are manageable. Thus, the ability to calculate fertilization cost accurately and rapidly assists the nursery operator in making timely management decisions. A microcomputer program was developed to calculate fertilization cost per container for one or combinations of the following methods of fertilizer application (MOA): broadcast, incorporation, injection, and top-dress.
`Silver Queen', `Incredible', and `Challenger' sweet corn (Zea mays L.) cultivars were evaluated at different nitrogen (N) fertilization rates at Springfield, Tenn., in 1993, 1994, and 1995. `Incredible' was more productive than `Silver Queen' and `Challenger'. Of the three cultivars, `Silver Queen' had the tallest plants, longest ears, and most attractive ears. Nitrogen fertilization rates were 0, 50, 100, and 150 (100 lb/acre at planting and 50 lb/acre sidedressed) lb/acre (0,56, 112, and 168 kg·ha-1). The 100 lb/acre rate of N applied at planting appeared to be sufficient for producing sweet corn in soils with an annual cropping frequency. Height of plants and ear diameters were larger at the higher fertilization rates, but differences among treatments were not great and were usually not significant. The cultivars of different genetic types did not differ in response to N fertilization rates. Cultivar × year interactions were significant for most factors evaluated, but most other interactions were not significant.
Fruit set and enlargement were compared for fertilized and unfertilized olive (Olea europaea L.) ovaries, the latter obtained by flower emasculation and bagging to prevent pollination. In the control population, the timing of abscission coincided with the onset of ovary expansion following fertilization. In the emasculated population, ovary expansion was only slight, and abscission was substantially delayed. Separation of the ovaries by size using graduated screens provided a useful tool for the evaluation of ovary growth.
In Santa Fe, Argentina, strawberries (Fragari ×ananassa Duch.) are cultivated in the area of Coronda where N fertilization usually exceeds crop requirements. The objective of this work was to test four types of fertilization methodology to optimize fertilizer use efficiency. Experiments were carried out at the horticultural center of the Facultad de Agronomía y Veterinaria, in Esperanza, Santa Fe, 31.15° S latitude, on a typical argiudol soil. `Chandler' was planted 13 Mar. 1996. Nitrogen demand was related to the dry matter production with N content decreasing to increment of biomass (W), soil N mineralization was estimated according to the program EDAFO version 3. Using previous data, a monthly balance was calculated and four treatments were devised: control (T0) = without fertilization; treatment 1 (T1) = N fertilization covering the accumulated monthly deficit, 53 kg·ha-1 (47 lb/acre); treatment 2 (T2) = N fertilization covering the monthly deficit 66 kg·ha-1 (58 lb/acre); treatment 3 (T3) = N fertilization covering the total crop demand 117 kg·ha-1 (104 lb/acre). All N treatments significantly increased yields over the control. Yield increased to increasing N rates from 0 to 53 kg·ha-1. This response was due to an increase in fruit number but not in fruit weight. High N rates promoted runner growth without increasing fruit yield. The use N balance method for strawberry fertilization showed satisfactory results. Accumulated N balance (T1), required the least amount of N fertilizer while producing good yield, thus it should be the method adopted to reduce costs and environmental risks of N fertilization.