Weed control fruit crops

Soil-applied pesticides have been successfully used to control soilbome diseases, weeds, and nematodes in most vegetable and fruit crops over the past decades. Toxicity of these materials to animals and humans and their environmental and economic costs (Pimentel et al. 1992 Ruzo 2006) raised serious environmental and human safety concerns, leading to the phase-out of the most effective and largely used chemical, the methyl bromide (Luken and Grof 2006), and the increasing restrictions on the applications of available pesticides (Perkins and Patterson 1997). The limited availability of chemicals resulted in an increased emphasis on... 

So far, it has been established that there is a very large market for crop protection agents globally and that these markets are dominated with crops such as wheat, barley, maize, soybeans, rice, cotton, grapes, top fruit and total weed control in countries and regions such as the USA,... 

The major crops for agrochemical use are cotton, rice, maize, vegetables and top fruit for insecticides small grain cereals, rice, vines and top fruit for fungicides, and maize, soybeans, small grain cereals, rice, industrial weed control, plantations and orchards for herbicides. Other crops that may be of interest include sugar beet, oil-seed rape, potatoes and citrus dependent upon your company s presence in these crops. 

Arsenic trioxide finds major use in the preparation of other compounds, notably those used in agricultural applications, The compounds monosodium methylarsonate. disodium methylarsonate, methane arsenic acid (cacodylic acid) are used for weed control, while arsenic acid, H3ASO4, is used as a desiccant for the defoliation of cotton crops, Other compounds once widely used in agriculture are calcium arsenate for control of boll weevils, lead arsenate as a pesticide for fruit crops, and sodium arsenite as a herbicide and for cattle and sheep dip. In some areas, arsenilic acid has been used as a feed additive for swine and poultry. Restrictions on these compounds vary from one country and region to the next. 

Just as atrazine is important in com, simazine is a pre-emergence triazine that provides broad-spectrum residual weed control in many of the important fruit and nut crops when applied either alone or in combination with a contact product such as glyphosate to control weeds at the time of application (Figure 1.5). 

In 2004, terbuthylazine continues to be a major component of herbicide programs in Europe, especially in com. At a country level, the Netherlands treats almost 100% of com, while on the low end, Austria treats 35% of com hectares with terbuthylazine. Approximately 60% of the combined area in corn production in Europe received terbuthylazine, including Germany, Italy, and Belgium. Terbuthylazine is used in more than 45 countries and remains a key weed control tool in crops such as com, sorghum, pea, bean, lupin, grape, pome fruit, citrus, and vine. 

Finally, certain triazine herbicides can be used selectively in orchards and in some horticultural crops. In this case, selectivity is not based only on physiological differences between species, but on physical selectivity associated with the location of the herbicide and the roots of the crop and weed species in the soil. Triazine herbicides such as simazine, which has very low solubility in water, remain close to the soil surface in most mineral soils. Careful application of simazine in horticultural or fruit crops can result in the herbicide being available to control shallow-rooted weed species without harming the deeper-rooted perennial species. The success of this use is dependent not only on the relative rooting depths of the tolerant and susceptible species, but also on soil conditions and other factors that may affect herbicide fate and movement. 

Lange, A.H. (1970). Weed control methods, losses and costs due to weeds, and benefits of weed control in deciduous fruit and nut crops. 

Triazine Herbicides for Weed Control in Fruit and Nut Crops... 

Simazine was the main product studied in early research on the triazines for weed control in tree fruits and vineyards (Doll, 1960 Larson and Ries, 1960). On mature grapevines in a deep, fine, and sandy loam soil, no differences in crop tolerance were observed between simazine and atrazine (Leonard and Lider, 1961). However, subsequent studies indicated that grapevines were more tolerant to simazine than to atrazine (Lange et al., 1969a). Prometryn was intermediate between the two in terms of crop tolerance (Lange et al., 1969a). 

Many triazines have been evaluated for weed control in orchards and vineyards, but primary emphasis will be placed on simazine as the herbicide of preference in most of these crops. In general, simazine is better tolerated by most tree fruits, nuts, and vines than high rates of atrazine, prometryn, propazine, terbutryn, terbuthylazine, or metribuzin. 

Prune and plum have less crop tolerance to simazine at high rates than the other stone fruit (Chaney et al, 1966 Elmore et al, 1970 Almoida et al, 1987). In a field experiment in California where simazine was applied for 2 years on French prune, Marianna 2624 plum rootstock, or Imperial prune on Myrobalan 29C plum rootstock, there was some phytotoxicity observed, though weed control was excellent and trunk diameter increased in most instances over an untreated check (Elmore et al, 1970). Simazine has been used with good crop tolerance at low rates for winter weeds, particularly in some of California s heavier soils. In California approximately 800 pounds of simazine were applied to 900 A of plum in 2004. 

Chemical Name 5-bromo-3-sec-butyl-6-methyluracil 5-bromo-6-methyl-3-(l-methylpropyl)-2,4-(l//,3//)pyrimidinedione Uses Herbicide applied to soil to control annual and perennial grasses, broadleaf weeds, and general vegetation on uncropped land also used for selective weed control in apple, asparagus, cane fruit, hops, and citrus crops. 

Uses herbicides/insecticides pre- or post-emergence control of broadleaf weeds in cereals, maize, lucerne, clover, trefoil, grass leys, potatoes, peas, onions, garlics, peas, leeks, soya beans, orchards, groundnuts, strawberries, vineyards and other crops for control of strawberry runners and raspberry suckers and overwintering forms of insect pests on fruit trees also used as a desiccant for leguminous seed crops destruction of potato haulms as a pre-harvest hop defoliant, etc. 

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