NITRATE REDUCTASE ACTIVITY ( NRA ) AT VEGETATIVE AND REPRODUCTIVE CONDI [ TIONS IN SACCHA RUM CULTIVAR CO
Regulations of flowering and induction of flowering in nonflowering clones of Saccharum has been found possible by the application of extra light (EL) and extra dark (ED) treatments. As to the effect of EL, ED and 'switch over' treatment from EL to ED on NRA relation to flowering NRA was found to be low at vegetative stage and as the plants reached the symptom stage. The activity reached a maximum value and thereafter showing a deckle with progress in flower development. Examination of gemplasm collection for NRA in clones of Saccharum species known to differ in their flowering behaviour was suggested.
Contributions to a biochemical study of sugarcane
SummaryFrom a study of the total iron (FeT), acid-soluble iron (FeS) and chlorophyll in the leaves of cane varieties, the fraction of iron bearing relation to chlorophyll (active iron, FeA) and that not related to chlorophyll (residual iron, FeR) have been calculated. FeR appears to bear relation to the growth of the cane varieties. A study of the variation of FeR/FeA ratio seems to be of help in determining whether the tendency of the plant, at a particular time, is more towards growth or accumulation of sucrose. It is shown that the factorf=FeR × FeS/FeA2 can serve as an index in the characterisation of cane varieties, in relation to early or late ripening character, even at an young age of 5 months.
PRECISION FARMING APPROACHES TO SMALL-FARM AGRICULTRUE
Precision farming implies a management strategy to increase productivity and economic returns with a reduced impact on the environment. It is based on the application of information technology to a description of variability in the field, variable-rate operations and the decisionmaking system. There are three technology levels and three strategies in the development of precision farming. Precision farming practices can be used on small farms as well as big ones, and they play a core role in rural development programs which are integrated with industry. A real-time soil spectrophotometer was developed to describe soil variability in farmers' fields, to be used in precision farming.