MSI99P0884 | |
Halais, P. | |
The detection of NPK deficiency trends in sugar cane crops by means of foliar diagnosis run from year to year on a follow-up basis | |
Periodical article | |
1963 | |
Proc. int. Soc. Sug. Cane Technol. | |
11, 214-221 | |
En | |
En | |
The criteria of 1.95 per cent N, 0.48 per cent P2O5 and 1.50 per cent K2O on the dry matter basis of the 3rd leaf central portion less mid-rib for ratoon cane crops aged 5 months has been firmly established following research carried out independently in Mauritius, Jamaica and British Guiana which enjoy tropical climates with normal summer rains. Thirteen different rules are given for proper leaf sampling to be carried out in summer when the canes are not sufferring from lack of moisture as judged by stem elongation rate exceeding 10 cm per week. A local index derived from weekly rainfall data may be used instead of regular stem measurements. Two samples, taken within the age limits of 3 and 7 moonths, should be bulked every year after being sampled from permanent and representative field units. Their nutrient contents should be standardized by means of an appropriate correction table to the normal age of 5 months. For each sugar plantation cultivating about 1000 ha of cane, the number of such sampling units each covering at least 10 ha should vary, according to the diversity of local conditions, from 10 to 20. Twice as many leaf samplings and the same number of NPK determinations wil be necessary each year. The accuracy of the analysis should always be checked against 'reference' samples from a standard laboratory in case the analysis is performed on the spot. The detection of deficiency trends is made by calculating, for each sampling unit independently, moving averages or median figures from the last three years' observations. A single graphical representation is used for each sampling unit and for the three nutrients as these are converted to the standard nitrogen basis by multiplying the P2O5 contents by 4.06 and the K2O contents by 1.30. In doing so the same criteria of 1.95 applies. The whole scheme requires good organization and patience, but its running cost is negligible compared with the fertilizer expenses and the bnenefit derived, in the long run, from improved cane nutrition. | |
SUGARCANE FOLIAR DIAGNOSIS NITROGEN POTASSIUM PHOSPHORUS PLANT NUTRITION | |
MAURITIUS | |
Sugarcane: Soils and plant nutrition | |
Fertilization: Nitrogen Fertilization: Phosphorus Fertilization: Potassium | |
1992-05-11 | |
En | |
Mauritius Sugar Industry Research Institute | |
LIB | |
CAT | |
CHEM |