תפריט נגישות
ניגודיות עדינהניגודיות גבוהה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
להורדת מודול נגישות חינם תפריט נגישותניגודיות עדינהניגודיות גבוההמונוכרוםהדגשת קישוריםחסימת אנימציהפונט קריאסגוראיפוס הגדרות נגישותלהורדת מודול נגישות חינםAdolfo G. Levin Northern R&D, Kiryat Shmona 11016, Israel Randy C. Ploetz University of Florida, Tropical Research & Education Center, Homestead, FL 33031 U.S.A.
Mango (Mangifera indica L.) is regarded as the king of fruits in India, where it has been cultivated for at least 4,000 years and has great cultural and religious significance (61,63). Many Indian mango cultivars originated in the fifteenth century when the best selections of mango seedlings were propagated by grafting and planted in large orchards, in some cases numbering 100,000 trees. With the arrival of voyagers to India from Europe, mango was soon established throughout the tropics and subtropics. Mango is an important commercial crop (63) that currently ranks fifth among the major fruits cultivated worldwide (14). It has flourished in recent years due to: (i) rapid expansion into growing areas of the Old World such as China and parts of Africa; (ii) cultivation of high quality clonal selections; (iii) adoption of modern agricultural practices, including irrigation management; (iv) integrated disease and pest management; and (v) the use of pesticides and other agrochemicals (38). Mango is cultivated commercially throughout the tropics and in many subtropical regions (45). The flowering response of mango differs greatly in tropical as opposed to subtropical environments. In the tropics, flowering can be induced chemically, while in the subtropics stimulation is ineffective and is primarily governed by chilling temperatures (28). Synchronization of vegetative growth to ensure that branch terminals are of the same physiological maturity, is a prerequisite in flowering management programs (11). A synchronized reproductive flush flowers once per year in the tropics after tip pruning and chemical treatments. In the subtropics, however, flowering occurs after 5 weeks of night temperatures below 15°C and day temperatures below 20°C (11). Mango malformation disease (MMD) is one of the most important and destructive diseases of this crop (30,58). It affects inflorescences and vegetative portions of the plant (Fig. 1). Although trees are not killed, the vegetative phase of the disease impedes canopy development and the floral phase reduces fruit yield dramatically; substantial economic losses can occur since malformed inflorescences do not bear fruit. In 1998, an estimated US$15 million of fruit was lost to the disease in Egypt (58), and losses in more important producing countries, e.g., India, are undoubtedly much greater (58,59). MMD was first reported in India in 1891 (29), and has subsequently been observed in Australia, Brazil, China, Egypt, El Salvador, India, Israel, Malaysia, Mexico, Myanmar, Nicaragua, Oman, Pakistan, Senegal, South Africa, Spain, Sri Lanka, Sudan, Swaziland, Uganda, and the United States (2,3,8,9,15,24,29,31,34,37,42, 51,55,64,67,70,77). Since the pathogen is easily disseminated in infected germplasm and there are conspicuous gaps in its geographic distribution, malformation may be even more widely spread (58).
Adolfo G. Levin Northern R&D, Kiryat Shmona 11016, Israel Randy C. Ploetz University of Florida, Tropical Research & Education Center, Homestead, FL 33031 U.S.A.
Mango (Mangifera indica L.) is regarded as the king of fruits in India, where it has been cultivated for at least 4,000 years and has great cultural and religious significance (61,63). Many Indian mango cultivars originated in the fifteenth century when the best selections of mango seedlings were propagated by grafting and planted in large orchards, in some cases numbering 100,000 trees. With the arrival of voyagers to India from Europe, mango was soon established throughout the tropics and subtropics. Mango is an important commercial crop (63) that currently ranks fifth among the major fruits cultivated worldwide (14). It has flourished in recent years due to: (i) rapid expansion into growing areas of the Old World such as China and parts of Africa; (ii) cultivation of high quality clonal selections; (iii) adoption of modern agricultural practices, including irrigation management; (iv) integrated disease and pest management; and (v) the use of pesticides and other agrochemicals (38). Mango is cultivated commercially throughout the tropics and in many subtropical regions (45). The flowering response of mango differs greatly in tropical as opposed to subtropical environments. In the tropics, flowering can be induced chemically, while in the subtropics stimulation is ineffective and is primarily governed by chilling temperatures (28). Synchronization of vegetative growth to ensure that branch terminals are of the same physiological maturity, is a prerequisite in flowering management programs (11). A synchronized reproductive flush flowers once per year in the tropics after tip pruning and chemical treatments. In the subtropics, however, flowering occurs after 5 weeks of night temperatures below 15°C and day temperatures below 20°C (11). Mango malformation disease (MMD) is one of the most important and destructive diseases of this crop (30,58). It affects inflorescences and vegetative portions of the plant (Fig. 1). Although trees are not killed, the vegetative phase of the disease impedes canopy development and the floral phase reduces fruit yield dramatically; substantial economic losses can occur since malformed inflorescences do not bear fruit. In 1998, an estimated US$15 million of fruit was lost to the disease in Egypt (58), and losses in more important producing countries, e.g., India, are undoubtedly much greater (58,59). MMD was first reported in India in 1891 (29), and has subsequently been observed in Australia, Brazil, China, Egypt, El Salvador, India, Israel, Malaysia, Mexico, Myanmar, Nicaragua, Oman, Pakistan, Senegal, South Africa, Spain, Sri Lanka, Sudan, Swaziland, Uganda, and the United States (2,3,8,9,15,24,29,31,34,37,42, 51,55,64,67,70,77). Since the pathogen is easily disseminated in infected germplasm and there are conspicuous gaps in its geographic distribution, malformation may be even more widely spread (58).
