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The application of micronutrients in citrus plants has usually been done by foliar spraying. The citrus plants are exigent in boron, zinc, manganese, iron and deficiency of these micronutrients is common in worldwide citriculture. In Brazilian citriculture, the B and Zn deficiencies are most frequent (Quaggio et al. 2003). For this reason, these micronutrients are routinely applied as foliar fertilizers (Boaretto et al. 1997).

The earlier workers (Kausar et al. 1979; Sillanpaa, 1982; Rashid, 1995) reported the micronutrients deficiency in soils and plants. The observation of farmers regarding the premature shedding of cotton squares and bolls provided the enough background to initiate the B research to determine its response by two major crops in the region. The high soil pH and presence of CaCO in soil are the main factors influencing the availability of B to plants (Barrow 1989; Lehto 1995; Mezuman and Keren 1981; Goldberg and Forster 1991; Elseewi, 1974; Elseewi and Almalky 1979). Keeping in view the importance of cotton and wheat in Pakistan, this study was initiated to determine the response of these crops to B on high-pH-calcareous soils.

Deficiencies of boron (B) and zinc (Zn) are well established in many agronomic and horticultural crops grown in calcareous soils of Pakistan (Rashid 2006). As crop responses to B as well as to Zn are appreciable and use of their fertilizers is highly cost–effective, application of these micronutrients is now recommended in the country. The history of Zn use in the country is about three decades old with rice being the first crop affected by its deficiency, and now Zn use is a regular practice in many crops including citrus, deciduous fruits and maize (Anonymous 1998; Rashid 1996). Establishment of field scale B deficiency in crops is a relatively a recent development and its formal use in the country started with cotton during late 1990s (Rashid and Rafique 2002). However, with the passage of time the magnitude and severity of B deficiency is increasing, primarily because of enhanced research information duration the past decade (Rashid et al. 2002).

Boron deficiency is a major reason for lower yield of wheat and mustard in Bangladesh. This element deficiency has arisen mainly due to continuous mining of soil nutrients for increased cropping intensity without adequate replenishment. Boron deficiency induces grain sterility. Again, crop species and varieties may differ in their sensitivity to boron deficiency (Rerkasem and Jamjod, 1997; Brown et al. 1999; Kataki et al. 2001). Wheat, next to rice, is the most important cereal crop and mustard ranks first among the oilseed crops in Bangladesh. These two crops are found to be much affected by B deficiency (Jahiruddin et al. 1995; Islam et al. 1997; Haque et al. 2000). The present study was undertaken to find out a suitable dose of B for these crops and also to screen out the crop varieties tolerant or sensitive to B deficiency.

The groundnut ( L.) is an important food legume and oilseeds crop of India grown in about 8 m ha land, the largest area in the world, but stand second in production due to its low productivity. Presently, the average productivity of groundnut, in India, is around 1300 kg ha which is very low as compared to USA and China mainly because, the crop is mostly grown as rain fed in dry lands, under low fertility and low input management, often subject to the vagaries of the weather conditions. However, in recent years, combination of improved genotypes and nutrient management practices has increased the productivity.

Apical dominance is the suppression of lateral shoots by a robustly growing shoot apex. The mechanism for this apical dominance is generally accepted to be through the polar flow of auxins, most notably indoleacetic acid (IAA), synthesized in the shoot apex and young leaves (Li et al. 2001).

Tart cherry ( L.) is commonly grown in Poland because of favorable soil and climate conditions. During the last 10 years, tart cherry fruit production in Poland varied from 140 to 180 thousand tons, accounting for ca. 20% of the world production (Kubiak, 2000). Introduction of mechanical harvest has increased an interest in culture of this species (Wawrzynczak, 2000). The export of tart cherry fruit to EU markets in the recent years has also stimulated production of this species in Poland. It is predicted that tart cherry production will gradually increase since fruit of this species are valuable for some products such as yoghurt, cream cheese, jam, juices, and marmalades (Kubiak, 2000).

Due to high pH and calcareousness of soil, the availability of micronutrients is affected (Talibudeed, 1981; Marschner, 1995) and growing citrus on such soils frequently shows deficiency symptoms like yellowing of young growth, interveinal chlorosis and dieback of branches. These are typical symptoms of iron (Fe) and zinc (Zn) deficiencies. Some short duration studies were conducted on micronutrients indicating their response specifically to Zn (Khattak, 1994; Siddique et al. 1994). The soil conditions are such that applied nutrients may not give immediate impact on yield in perennial plants like citrus due to their limited root system and hairs on roots absorbing nutrients from surface soil (Cohen, 19976). Moreover, impact of environmental factors is more affective on fruit plants as compared to field crops due to many reasons not mentioned here. Keeping in view the existing status of information and importance of citrus fruits in Pakistan, a long-term study regarding micronutrient effects on fruit yield is planned and two methods of nutrient application are tested in two separate experiments in farmers’ Mandarin. Up to the end of 2004, two years fruit-yield data have been taken.

Turkey has world’s boron mineral deposit, refined borate production capacity of about 800.000 t/y and borate ore production capacity of 1.800.000 t/y. The National Boron Research Institute “BOREN” was established under the authority of Ministry of Energy and National Resources. Main aim of BOREN is to increase the consumption of boron products and broaden the production range from refined boron products to commercial products. For this purpose new investigations concerning the uses of boron in glass, fiberglass, ceramics, building materials, detergents, flame retardants and wood preservation have been programmed. Boron products for health and agriculture are essentially in the scope of BOREN for the benefit of mankind. In this perspective, the role of BOREN will be forming a bridge between Public Institutions, Industrial Foundations, Universities, Research and Development Institutions, Independent Researchers and Consultants. From this point of view BOREN is associating and grouping the independent studies in related fields at all organizations mentioned above. Hence these studies will be able to lead to a useful product for technology. Since its establishment; BOREN has been forming a data collection system for studies about scientific and technological investigations as well as boron effects on plant nutrition and human health and is willing to cooperate with entrepreneurs all around the world to enlarge the use and benefit of boron minerals and enhance the market oriented product development.

Oil palm ( Jacq.) is grown on more than 12 million hectares in the humid tropics mainly between latitude 10°N and 10°S. It produces about 27% of the world’s crop in the world, and it requires a relatively high amount of B to sustain its growth and production despite being a monocotyledon (Shorrocks, 1997). In fact, it is one of the 16 plants regarded as most sensitive to B deficiency and highly responsive to B application (Shorrocks, 1997).