Pears harvesting

Fruits are seasonal in temperate climates, and a good harvest may be followed by a shortage if there is no method of preservation. The hard fruits, apples and pears, have traditionally been stored in cool places and may then last for several months, depending on the variety Refrigeration has extended the storage life, and made this more reliable. 

The determination of DDT residue on apples grown in the Hood River fruit district and on pears at Medford is carried on in branch laboratories established in those areas. The majority of samples selected for analyses are suspected of carrying higher amounts of residue than the average because of the spray program used or because the last application of insecticide was made within a few weeks of harvest. As indicated by Table I, about 80% of all the samples analyzed carried 3.0 p.p.m. or less of DDT during the past harvest season. Only about 20% of the samples showed residues above 3.0 p.p.m. six samples showed residue deposits slightly above 7.0 p.p.m. 

A sample of hops which had been treated with tetraethyl pyrophosphate showed a negative chemical analysis. The plant material was also extracted and the extract added to the drinking water of test animals and sensitive insects. The animals and insects that drank this treated water for several days showed no reaction. With the sensitive insects it would have been possible to detect even a few parts per million. In addition, there have been extensive commercial field applications of the chemical in dust and spray form to crops such as apples, pears, grapes, celery, broccoli, Brussels sprouts, and others up to within a few days of harvest there has been no detectable poison residue on any of the crops. The lack of poison residue with use of tetraethyl pyrophosphate is due to the fact that it hydrolyzes within a few hours of application, breaking down into transient nonresidual and nonpoisonous chemicals. Thus it is possible to use tetraethyl pyrophosphate well up to harvest time of food products without danger of residual poison on crops. The fact that the chemical is used in extremely small amounts is a definite advantage in respect to freedom from poison residue. 

Surface residues of DDT and parathion at various times during the season and at harvest were determined for apples, pears, peaches, oranges, and lemons. Low level surface residues of parathion on apples were not carried over into cider. Harvest residues on fresh fruit are distinguished from residues present in food at the time of consumption which are included under the designation ultimate residues. 

Table II. Surface Residues of DDT on Bartlett Pears at Harvest ...

On pears, experimental applications of DDT applied in commercial schedules resulted in surface residues ranging from less than 0.5 to approximately 3 p.p.m. Typical harvest residues are shown in Table II. 

On pears (Table IV) parathion residues resulting from ten varied schedules did not exceed 0.08 p.p.m. at harvest. (These values are derived from samples containing an optimum amount of parathion for analytical precision.) Intervals between the terminal application and harvest ranged from 7 to 33 days. 

Further wash tests with apples and pears have not been extensive because the magnitudes of typical DDT harvest residues suggest that no appreciable difficulty will be encountered in bringing fruits sprayed with the lower dosages under the provisional tolerance for DDT residues on these fruits. 

Lendieric I, Pinto E, Vendrell M and Larrigaudiere C. 1999. Harvest date affects die antioxidative system in pear fruits. J Hort Sci Technol 74(6) 791—795. 

To produce fruit, pears need to be pollinated by another compatible cultivar—that is, you need to grow two different pears—and their compatibility groupings are quite complex, so seek advice when you buy. A specialty fruit nursery or mail order company can advise you on appropriate combinations of cultivars. Pears are slower to start cropping than apples. It is well worth buying a tree grown for three years In the nursery to shorten the time before you harvest your first crop. 

Harvesting pears Other than early cultivars, pears should not be left to ripen on the tree, as flavor will be poor. If you have room, choose a selection of cultivars for a succession of fruits. 

Deciduous fruit plants that lose their leaves each winter and become dormant include apple, pear, peach, prune, plum, cherry, apricot, fig, grape, bramble, and bush fruits. The deciduous nut crops include principally walnut, almond, pecan, pistachio, and hazelnut (filbert). Nearly 11 million tons (10 million metric tons) of fruit come from deciduous plants grown in 43 states in the United States. In 1998 in California alone, 8.9 million tons (8.1 metric tons) of fruits and nuts were harvested (Olds, 1998). Strawberry and pineapple, though not deciduous fruits, are included in this chapter because of triazine use on fruit crops. The major growing areas for the United States are shown in Table 17.1, and these same crops are grown in many countries throughout the world. 

The main difference between botrytized wines and other nonfortified sweet wines, for example, late-harvest wines, icewines (eiswein), or straw wines, is the extreme range and richness of the aroma compounds produced by Botrytis. Marked differences also exist in some other components (e.g., glycerol, acid composition), due to the microbial activity. According to the descriptors most often applied to these wines, they are characterized by peach, apricot, pear, quince, raisin, and honey flavors, combined with distinctive "botrytis or roti aspects. Another typical feature of botrytized wines is their high acid contents. These prevent them from appearing cloying, even if the sugar content is commonly over 200 g/1. 

Trichlorfon is mostly used to kill mangold fly larvae it is also very efficient against the dangerous rice weevil, which can destroy whole harvests. Trichlorfon is successfully used in viticulture (to kill grapevine moths) and pomiculture (to kill apple, pear and plum sawflies, apple ermine moths and gooseberry sawflies). Trichlorfon is very efficient in cot-ton-growing (to kill cotton worms). The low toxicity of trichlorfon for warm-blooded animals accounts for its use in veterinary medicine to combat parasites on large animals. 

Kevers, C Pincemail, J.I. Tabart, J. Defraigne, J. Dommes, J. 2011. Influence of cultivar, harvest time, storage conditions, and peeling on the antioxidant capacity and phenolic and ascorbic acid contents of apples and pears. J. Agric. Food Chem. 59 6165 6171. 

In farms, fruit of different varieties are grown and harvested according to particular harvests periods. Apples and pears are considered in this work. Each day of the harvesting period, OFs produce a certain amount of fruit of each variety. From the company s point of view, the production of its farms can be processed in its own PPs (XI) and CJPs (X2). The production and quality distribution per variety in each farm... 

To demonstrate the performance of the proposed approach a FISC that comprehends one item of each instance in Fig. 1 is considered. Model data (plant and storage capacities, costs, distances, production averages and deviations, harvesting periods, etc.) can be found in [1]. Although several varieties of pears and apples exist, for the sake of simplicity, in the present model all varieties of each fruit are lumped into apples and pears . As well, although many different types of packed fruit are produced for the different markets, only regional and overseas packed fruit is considered in this model. 

Laidou, I. A., Thanassoulopoulos, C.C., and Liakopoulou-Kyriakides, M. 2001. Diffusion of patulin in the flesh of pears inoculated with four post-harvest pathogens. J. Phytopathol. 149, 457-461. Larsen, T.O., Frisvad, J.C., Ravn, G., and Skaaning, T. 1998. Mycotoxin production by Penicillium expansum on black currant and cherry juice. Food Addit. Contam. 15, 671-675. 

Before windsurfing became a big hit, Hood River was famous among epicureans for its orchards and vineyards. The area s fruits are coveted by gourmet chefs worldwide. In the autumn, take a drive down the Mt. Hood Loop tour and stop at any of the fruit stands along the way. Another way to enjoy the local bounty is to visit the Hood River Harvest Festival held in mid-October. Pick up locally grown winter pears, Bartletts, Newton apples, cherries and peaches amid a backdrop of colorful fall foliage. Admission to the festival is free. 

Pick the best pears from your harvest. If you want to peel, halve and core the pears, quickly blanch them afterwards in boiling water for two minutes, then put them in cold water. 

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