Weed control citrus

CgH,3BrN202. A soil-acting herbicide. White crystalline solid, m.p. 158-159" C. It is a non-selective inhibitor of photosynthesis used for weed control In citrus and cane fruit plantations. It is relatively non-toxic to animal life. 

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. 

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. 

Benefits of Triazine Herbicides and Other Weed Control Technology in Citrus Management... 

Simazine was among the first herbicides registered for use in Florida citrus in 1962 and was recommended by the University of Florida as an excellent weed control tool for citrus (Kretchman and McCown, 1962). This early registration of simazine was for the control of annual weeds, while today s registration includes broadleaf weeds, annual vines, and annual grasses (Singh and Tucker, 1987). 

Triazine herbicides have provided a significant contribution to the effective control of weeds in citrus around the world and still are major tools in citrus weed management strategies. 

This chapter will deal with citrus losses caused by weeds, major weeds infesting citrus groves around the globe, and controlling weeds in citrus with a special emphasis on triazine herbicides. A brief description of the control measures available in different parts of the world and their limitations are discussed. 

Slashing, Hand Hoeing, and Mulching Bredell (1973) compared several physical methods with chemical measures to control weeds in citrus. Herbicides were found to be the most effective tool in managing weeds. Depending... 

Weed Control with Hot Water Hot water to control weeds in citrus orchards and in other crops has shown potential (Anonymous, 1993a, b). The results of such treatments were comparable to contact herbicides. 

Insects This method has received little attention as a means of combating weeds in citrus. Habeck (1977) showed that insects could be used against largeleaf lantana and stranglervine. A number of leaf-mining beetles have been used successfully in Australia and Hawaii to control largeleaf lantana, which is a major weed in Florida citrus orchards (Tucker and Singh, 1983). 

Chemical weed control practices in citrus have been thoroughly reviewed by various researchers (Ryan, 1969 Jordan et al, 1977 Jordan, 1978 Tucker and Singh, 1983 Mersie and Singh, 1989 Singh el al., 1990 Sharma and Singh, 1999). Herbicides used in citrus can be divided into two groups soil-applied (preemergence) and... 

Ametryn, another triazine herbicide, was previously used for weed control in citrus. This herbicide first appeared in recommendations in 1979 for control of broadleaf weeds, annual grasses, and some perennial grasses. Ametryn was recommended at use rates of 3.6-7.2kg a.i./ha, with a maximum of 5.4kg a.i./ha for both shallow, poorly drained flatwood soils (soils having more organic matter and clay) and bedded groves (trees planted on raised beds). It was recommended that ametryn should not be applied to trees less than 2 years old. Between 1984 and 1988 the application rates were increased to 7.2-10.8kg a.i./ha, with the annual rate not to exceed 13.6kg a.i./ha, and with lower rates... 

Pickett et al. (1992) reported that California citrus growers depend on herbicides for weed control. Simazine was rated as the most important herbicide used in citrus production. Abdel-Rehman et al (1994) reported that control of annual broadleaf weeds was most effective with simazine plus fluazifop and least effective with fhiazifop alone. Application of diuron or atrazine once at 1-4kg a.i./ha or twice at 1 + 1, 1 + 2 or 2 + 2kg a.i./ha, significantly reduced grasses and broadleaf weeds. Broadleaf weeds were controlled by 2-4kg a.i./ha of diuron and 2 + 2kg a.i./ ha of simazine at the 60-day sampling period (Singh et al, 1987). Perez (1976) reported that fluometuron, diuron, monuron, and simazine, all at 4.8kg a.i./ha, and bromacil at 4kg a.i./ha controlled weeds without injury to citrus on latosols, while simazine and diuron at 4.8 kg a.i./ha or bromacil at 4kg a.i./ha caused no injury to grapefruit after two applications on sandy soil. 

Abdel-Rehman, A.M., S.E. Salem, and S.S. Moustafa (1994). Studies on chemical weed control in citrus seed beds. Bullet. Faculty Agri., Univ. Cairo., 45 905-918. 

Day, B.E. (1955). Urea herbicides for citrus weed control. Calif. Citrogr., 40 398, 408-413. 

Day B.E. and L.S. Jordan (1967). Noncultivation weed control in citrus. Proc. XVII Inti. Hort. Congr., Ill 137-143. East Lansing, Michigan International Horticulture Society. 

DeBarreda, D.G. (1977). Present status of weed control practices in Spain. Proc. Inti. Citrus Symp., 1 158-161. Valencia, Spain Internatonal Society of Citriculture. 

DeBarreda. D.G. and A. DelBusto (1981). Evaluation of glyphosate for weed control in citrus orchards of Spain. Proc. Inti. Soc. 

DelBosco, G.F., A. DeMichele, and B. Baratta (1974). Chemical weed control in Sicilian citriculture. In D.P.H. Tucker and R.L. Phillips, eds., Perennial Grass Control in Florida Citrus Groves. Murcia, Spain Ministerio de Agriculture, pp. 357-359. 

FAO (Food and Agriculture Organization of United Nations) (2003). FAO Yearbook of Production. Rome, Italy FAO Statistics Division. Futch, S.H. (1997) Horticultural and environmental aspects of weed control in Florida citrus. Ph.D. thesis. University of Florida, Gainsville. 

Giudice, V.L. (1981). Present status of citrus weed control in Italy. Proc. Inti. Soc. Citriculture, 2 486 -87. 

Habeck, D.H. (1977). The potential of using insects for biological control of weeds in citrus. Proc. Inti. Soc. Citriculture, 1 146-148. Hall, D. and D.P.H. Tucker (1987). Prevention is the best strategy for combating goatweed. Citrus Ind., 68 34-38. 

Herholdt, J.A. (1969). Weed control in South African citrus orchards. Proc. 1st Inti. Citrus Symp., 1 499-502. Riverside, CA University of California. 

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